1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2009, Microsoft Corporation.
4 *
5 * Authors:
6 * Haiyang Zhang <haiyangz@microsoft.com>
7 * Hank Janssen <hjanssen@microsoft.com>
8 * K. Y. Srinivasan <kys@microsoft.com>
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/wait.h>
13 #include <linux/sched.h>
14 #include <linux/completion.h>
15 #include <linux/string.h>
16 #include <linux/mm.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/module.h>
21 #include <linux/device.h>
22 #include <linux/hyperv.h>
23 #include <linux/blkdev.h>
24 #include <scsi/scsi.h>
25 #include <scsi/scsi_cmnd.h>
26 #include <scsi/scsi_host.h>
27 #include <scsi/scsi_device.h>
28 #include <scsi/scsi_tcq.h>
29 #include <scsi/scsi_eh.h>
30 #include <scsi/scsi_devinfo.h>
31 #include <scsi/scsi_dbg.h>
32 #include <scsi/scsi_transport_fc.h>
33 #include <scsi/scsi_transport.h>
34
35 /*
36 * All wire protocol details (storage protocol between the guest and the host)
37 * are consolidated here.
38 *
39 * Begin protocol definitions.
40 */
41
42 /*
43 * Version history:
44 * V1 Beta: 0.1
45 * V1 RC < 2008/1/31: 1.0
46 * V1 RC > 2008/1/31: 2.0
47 * Win7: 4.2
48 * Win8: 5.1
49 * Win8.1: 6.0
50 * Win10: 6.2
51 */
52
53 #define VMSTOR_PROTO_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
54 (((MINOR_) & 0xff)))
55
56 #define VMSTOR_PROTO_VERSION_WIN6 VMSTOR_PROTO_VERSION(2, 0)
57 #define VMSTOR_PROTO_VERSION_WIN7 VMSTOR_PROTO_VERSION(4, 2)
58 #define VMSTOR_PROTO_VERSION_WIN8 VMSTOR_PROTO_VERSION(5, 1)
59 #define VMSTOR_PROTO_VERSION_WIN8_1 VMSTOR_PROTO_VERSION(6, 0)
60 #define VMSTOR_PROTO_VERSION_WIN10 VMSTOR_PROTO_VERSION(6, 2)
61
62 /* Packet structure describing virtual storage requests. */
63 enum vstor_packet_operation {
64 VSTOR_OPERATION_COMPLETE_IO = 1,
65 VSTOR_OPERATION_REMOVE_DEVICE = 2,
66 VSTOR_OPERATION_EXECUTE_SRB = 3,
67 VSTOR_OPERATION_RESET_LUN = 4,
68 VSTOR_OPERATION_RESET_ADAPTER = 5,
69 VSTOR_OPERATION_RESET_BUS = 6,
70 VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
71 VSTOR_OPERATION_END_INITIALIZATION = 8,
72 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
73 VSTOR_OPERATION_QUERY_PROPERTIES = 10,
74 VSTOR_OPERATION_ENUMERATE_BUS = 11,
75 VSTOR_OPERATION_FCHBA_DATA = 12,
76 VSTOR_OPERATION_CREATE_SUB_CHANNELS = 13,
77 VSTOR_OPERATION_MAXIMUM = 13
78 };
79
80 /*
81 * WWN packet for Fibre Channel HBA
82 */
83
84 struct hv_fc_wwn_packet {
85 u8 primary_active;
86 u8 reserved1[3];
87 u8 primary_port_wwn[8];
88 u8 primary_node_wwn[8];
89 u8 secondary_port_wwn[8];
90 u8 secondary_node_wwn[8];
91 };
92
93
94
95 /*
96 * SRB Flag Bits
97 */
98
99 #define SRB_FLAGS_QUEUE_ACTION_ENABLE 0x00000002
100 #define SRB_FLAGS_DISABLE_DISCONNECT 0x00000004
101 #define SRB_FLAGS_DISABLE_SYNCH_TRANSFER 0x00000008
102 #define SRB_FLAGS_BYPASS_FROZEN_QUEUE 0x00000010
103 #define SRB_FLAGS_DISABLE_AUTOSENSE 0x00000020
104 #define SRB_FLAGS_DATA_IN 0x00000040
105 #define SRB_FLAGS_DATA_OUT 0x00000080
106 #define SRB_FLAGS_NO_DATA_TRANSFER 0x00000000
107 #define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT)
108 #define SRB_FLAGS_NO_QUEUE_FREEZE 0x00000100
109 #define SRB_FLAGS_ADAPTER_CACHE_ENABLE 0x00000200
110 #define SRB_FLAGS_FREE_SENSE_BUFFER 0x00000400
111
112 /*
113 * This flag indicates the request is part of the workflow for processing a D3.
114 */
115 #define SRB_FLAGS_D3_PROCESSING 0x00000800
116 #define SRB_FLAGS_IS_ACTIVE 0x00010000
117 #define SRB_FLAGS_ALLOCATED_FROM_ZONE 0x00020000
118 #define SRB_FLAGS_SGLIST_FROM_POOL 0x00040000
119 #define SRB_FLAGS_BYPASS_LOCKED_QUEUE 0x00080000
120 #define SRB_FLAGS_NO_KEEP_AWAKE 0x00100000
121 #define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE 0x00200000
122 #define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT 0x00400000
123 #define SRB_FLAGS_DONT_START_NEXT_PACKET 0x00800000
124 #define SRB_FLAGS_PORT_DRIVER_RESERVED 0x0F000000
125 #define SRB_FLAGS_CLASS_DRIVER_RESERVED 0xF0000000
126
127 #define SP_UNTAGGED ((unsigned char) ~0)
128 #define SRB_SIMPLE_TAG_REQUEST 0x20
129
130 /*
131 * Platform neutral description of a scsi request -
132 * this remains the same across the write regardless of 32/64 bit
133 * note: it's patterned off the SCSI_PASS_THROUGH structure
134 */
135 #define STORVSC_MAX_CMD_LEN 0x10
136
137 #define POST_WIN7_STORVSC_SENSE_BUFFER_SIZE 0x14
138 #define PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE 0x12
139
140 #define STORVSC_SENSE_BUFFER_SIZE 0x14
141 #define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14
142
143 /*
144 * Sense buffer size changed in win8; have a run-time
145 * variable to track the size we should use. This value will
146 * likely change during protocol negotiation but it is valid
147 * to start by assuming pre-Win8.
148 */
149 static int sense_buffer_size = PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE;
150
151 /*
152 * The storage protocol version is determined during the
153 * initial exchange with the host. It will indicate which
154 * storage functionality is available in the host.
155 */
156 static int vmstor_proto_version;
157
158 #define STORVSC_LOGGING_NONE 0
159 #define STORVSC_LOGGING_ERROR 1
160 #define STORVSC_LOGGING_WARN 2
161
162 static int logging_level = STORVSC_LOGGING_ERROR;
163 module_param(logging_level, int, S_IRUGO|S_IWUSR);
164 MODULE_PARM_DESC(logging_level,
165 "Logging level, 0 - None, 1 - Error (default), 2 - Warning.");
166
do_logging(int level)167 static inline bool do_logging(int level)
168 {
169 return logging_level >= level;
170 }
171
172 #define storvsc_log(dev, level, fmt, ...) \
173 do { \
174 if (do_logging(level)) \
175 dev_warn(&(dev)->device, fmt, ##__VA_ARGS__); \
176 } while (0)
177
178 struct vmscsi_win8_extension {
179 /*
180 * The following were added in Windows 8
181 */
182 u16 reserve;
183 u8 queue_tag;
184 u8 queue_action;
185 u32 srb_flags;
186 u32 time_out_value;
187 u32 queue_sort_ey;
188 } __packed;
189
190 struct vmscsi_request {
191 u16 length;
192 u8 srb_status;
193 u8 scsi_status;
194
195 u8 port_number;
196 u8 path_id;
197 u8 target_id;
198 u8 lun;
199
200 u8 cdb_length;
201 u8 sense_info_length;
202 u8 data_in;
203 u8 reserved;
204
205 u32 data_transfer_length;
206
207 union {
208 u8 cdb[STORVSC_MAX_CMD_LEN];
209 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
210 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
211 };
212 /*
213 * The following was added in win8.
214 */
215 struct vmscsi_win8_extension win8_extension;
216
217 } __attribute((packed));
218
219 /*
220 * The list of storage protocols in order of preference.
221 */
222 struct vmstor_protocol {
223 int protocol_version;
224 int sense_buffer_size;
225 int vmscsi_size_delta;
226 };
227
228
229 static const struct vmstor_protocol vmstor_protocols[] = {
230 {
231 VMSTOR_PROTO_VERSION_WIN10,
232 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
233 0
234 },
235 {
236 VMSTOR_PROTO_VERSION_WIN8_1,
237 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
238 0
239 },
240 {
241 VMSTOR_PROTO_VERSION_WIN8,
242 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
243 0
244 },
245 {
246 VMSTOR_PROTO_VERSION_WIN7,
247 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
248 sizeof(struct vmscsi_win8_extension),
249 },
250 {
251 VMSTOR_PROTO_VERSION_WIN6,
252 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
253 sizeof(struct vmscsi_win8_extension),
254 }
255 };
256
257
258 /*
259 * This structure is sent during the initialization phase to get the different
260 * properties of the channel.
261 */
262
263 #define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL 0x1
264
265 struct vmstorage_channel_properties {
266 u32 reserved;
267 u16 max_channel_cnt;
268 u16 reserved1;
269
270 u32 flags;
271 u32 max_transfer_bytes;
272
273 u64 reserved2;
274 } __packed;
275
276 /* This structure is sent during the storage protocol negotiations. */
277 struct vmstorage_protocol_version {
278 /* Major (MSW) and minor (LSW) version numbers. */
279 u16 major_minor;
280
281 /*
282 * Revision number is auto-incremented whenever this file is changed
283 * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
284 * definitely indicate incompatibility--but it does indicate mismatched
285 * builds.
286 * This is only used on the windows side. Just set it to 0.
287 */
288 u16 revision;
289 } __packed;
290
291 /* Channel Property Flags */
292 #define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
293 #define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
294
295 struct vstor_packet {
296 /* Requested operation type */
297 enum vstor_packet_operation operation;
298
299 /* Flags - see below for values */
300 u32 flags;
301
302 /* Status of the request returned from the server side. */
303 u32 status;
304
305 /* Data payload area */
306 union {
307 /*
308 * Structure used to forward SCSI commands from the
309 * client to the server.
310 */
311 struct vmscsi_request vm_srb;
312
313 /* Structure used to query channel properties. */
314 struct vmstorage_channel_properties storage_channel_properties;
315
316 /* Used during version negotiations. */
317 struct vmstorage_protocol_version version;
318
319 /* Fibre channel address packet */
320 struct hv_fc_wwn_packet wwn_packet;
321
322 /* Number of sub-channels to create */
323 u16 sub_channel_count;
324
325 /* This will be the maximum of the union members */
326 u8 buffer[0x34];
327 };
328 } __packed;
329
330 /*
331 * Packet Flags:
332 *
333 * This flag indicates that the server should send back a completion for this
334 * packet.
335 */
336
337 #define REQUEST_COMPLETION_FLAG 0x1
338
339 /* Matches Windows-end */
340 enum storvsc_request_type {
341 WRITE_TYPE = 0,
342 READ_TYPE,
343 UNKNOWN_TYPE,
344 };
345
346 /*
347 * SRB status codes and masks; a subset of the codes used here.
348 */
349
350 #define SRB_STATUS_AUTOSENSE_VALID 0x80
351 #define SRB_STATUS_QUEUE_FROZEN 0x40
352 #define SRB_STATUS_INVALID_LUN 0x20
353 #define SRB_STATUS_SUCCESS 0x01
354 #define SRB_STATUS_ABORTED 0x02
355 #define SRB_STATUS_ERROR 0x04
356 #define SRB_STATUS_DATA_OVERRUN 0x12
357
358 #define SRB_STATUS(status) \
359 (status & ~(SRB_STATUS_AUTOSENSE_VALID | SRB_STATUS_QUEUE_FROZEN))
360 /*
361 * This is the end of Protocol specific defines.
362 */
363
364 static int storvsc_ringbuffer_size = (128 * 1024);
365 static u32 max_outstanding_req_per_channel;
366 static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth);
367
368 static int storvsc_vcpus_per_sub_channel = 4;
369 static unsigned int storvsc_max_hw_queues;
370
371 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
372 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
373
374 module_param(storvsc_max_hw_queues, uint, 0644);
375 MODULE_PARM_DESC(storvsc_max_hw_queues, "Maximum number of hardware queues");
376
377 module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
378 MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
379
380 static int ring_avail_percent_lowater = 10;
381 module_param(ring_avail_percent_lowater, int, S_IRUGO);
382 MODULE_PARM_DESC(ring_avail_percent_lowater,
383 "Select a channel if available ring size > this in percent");
384
385 /*
386 * Timeout in seconds for all devices managed by this driver.
387 */
388 static int storvsc_timeout = 180;
389
390 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
391 static struct scsi_transport_template *fc_transport_template;
392 #endif
393
394 static struct scsi_host_template scsi_driver;
395 static void storvsc_on_channel_callback(void *context);
396
397 #define STORVSC_MAX_LUNS_PER_TARGET 255
398 #define STORVSC_MAX_TARGETS 2
399 #define STORVSC_MAX_CHANNELS 8
400
401 #define STORVSC_FC_MAX_LUNS_PER_TARGET 255
402 #define STORVSC_FC_MAX_TARGETS 128
403 #define STORVSC_FC_MAX_CHANNELS 8
404
405 #define STORVSC_IDE_MAX_LUNS_PER_TARGET 64
406 #define STORVSC_IDE_MAX_TARGETS 1
407 #define STORVSC_IDE_MAX_CHANNELS 1
408
409 /*
410 * Upper bound on the size of a storvsc packet. vmscsi_size_delta is not
411 * included in the calculation because it is set after STORVSC_MAX_PKT_SIZE
412 * is used in storvsc_connect_to_vsp
413 */
414 #define STORVSC_MAX_PKT_SIZE (sizeof(struct vmpacket_descriptor) +\
415 sizeof(struct vstor_packet))
416
417 struct storvsc_cmd_request {
418 struct scsi_cmnd *cmd;
419
420 struct hv_device *device;
421
422 /* Synchronize the request/response if needed */
423 struct completion wait_event;
424
425 struct vmbus_channel_packet_multipage_buffer mpb;
426 struct vmbus_packet_mpb_array *payload;
427 u32 payload_sz;
428
429 struct vstor_packet vstor_packet;
430 };
431
432
433 /* A storvsc device is a device object that contains a vmbus channel */
434 struct storvsc_device {
435 struct hv_device *device;
436
437 bool destroy;
438 bool drain_notify;
439 atomic_t num_outstanding_req;
440 struct Scsi_Host *host;
441
442 wait_queue_head_t waiting_to_drain;
443
444 /*
445 * Each unique Port/Path/Target represents 1 channel ie scsi
446 * controller. In reality, the pathid, targetid is always 0
447 * and the port is set by us
448 */
449 unsigned int port_number;
450 unsigned char path_id;
451 unsigned char target_id;
452
453 /*
454 * The size of the vmscsi_request has changed in win8. The
455 * additional size is because of new elements added to the
456 * structure. These elements are valid only when we are talking
457 * to a win8 host.
458 * Track the correction to size we need to apply. This value
459 * will likely change during protocol negotiation but it is
460 * valid to start by assuming pre-Win8.
461 */
462 int vmscsi_size_delta;
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 /*
478 * Serializes modifications of stor_chns[] from storvsc_do_io()
479 * and storvsc_change_target_cpu().
480 */
481 spinlock_t lock;
482 /* Used for vsc/vsp channel reset process */
483 struct storvsc_cmd_request init_request;
484 struct storvsc_cmd_request reset_request;
485 /*
486 * Currently active port and node names for FC devices.
487 */
488 u64 node_name;
489 u64 port_name;
490 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
491 struct fc_rport *rport;
492 #endif
493 };
494
495 struct hv_host_device {
496 struct hv_device *dev;
497 unsigned int port;
498 unsigned char path;
499 unsigned char target;
500 struct workqueue_struct *handle_error_wq;
501 struct work_struct host_scan_work;
502 struct Scsi_Host *host;
503 };
504
505 struct storvsc_scan_work {
506 struct work_struct work;
507 struct Scsi_Host *host;
508 u8 lun;
509 u8 tgt_id;
510 };
511
storvsc_device_scan(struct work_struct * work)512 static void storvsc_device_scan(struct work_struct *work)
513 {
514 struct storvsc_scan_work *wrk;
515 struct scsi_device *sdev;
516
517 wrk = container_of(work, struct storvsc_scan_work, work);
518
519 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
520 if (!sdev)
521 goto done;
522 scsi_rescan_device(&sdev->sdev_gendev);
523 scsi_device_put(sdev);
524
525 done:
526 kfree(wrk);
527 }
528
storvsc_host_scan(struct work_struct * work)529 static void storvsc_host_scan(struct work_struct *work)
530 {
531 struct Scsi_Host *host;
532 struct scsi_device *sdev;
533 struct hv_host_device *host_device =
534 container_of(work, struct hv_host_device, host_scan_work);
535
536 host = host_device->host;
537 /*
538 * Before scanning the host, first check to see if any of the
539 * currrently known devices have been hot removed. We issue a
540 * "unit ready" command against all currently known devices.
541 * This I/O will result in an error for devices that have been
542 * removed. As part of handling the I/O error, we remove the device.
543 *
544 * When a LUN is added or removed, the host sends us a signal to
545 * scan the host. Thus we are forced to discover the LUNs that
546 * may have been removed this way.
547 */
548 mutex_lock(&host->scan_mutex);
549 shost_for_each_device(sdev, host)
550 scsi_test_unit_ready(sdev, 1, 1, NULL);
551 mutex_unlock(&host->scan_mutex);
552 /*
553 * Now scan the host to discover LUNs that may have been added.
554 */
555 scsi_scan_host(host);
556 }
557
storvsc_remove_lun(struct work_struct * work)558 static void storvsc_remove_lun(struct work_struct *work)
559 {
560 struct storvsc_scan_work *wrk;
561 struct scsi_device *sdev;
562
563 wrk = container_of(work, struct storvsc_scan_work, work);
564 if (!scsi_host_get(wrk->host))
565 goto done;
566
567 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
568
569 if (sdev) {
570 scsi_remove_device(sdev);
571 scsi_device_put(sdev);
572 }
573 scsi_host_put(wrk->host);
574
575 done:
576 kfree(wrk);
577 }
578
579
580 /*
581 * We can get incoming messages from the host that are not in response to
582 * messages that we have sent out. An example of this would be messages
583 * received by the guest to notify dynamic addition/removal of LUNs. To
584 * deal with potential race conditions where the driver may be in the
585 * midst of being unloaded when we might receive an unsolicited message
586 * from the host, we have implemented a mechanism to gurantee sequential
587 * consistency:
588 *
589 * 1) Once the device is marked as being destroyed, we will fail all
590 * outgoing messages.
591 * 2) We permit incoming messages when the device is being destroyed,
592 * only to properly account for messages already sent out.
593 */
594
get_out_stor_device(struct hv_device * device)595 static inline struct storvsc_device *get_out_stor_device(
596 struct hv_device *device)
597 {
598 struct storvsc_device *stor_device;
599
600 stor_device = hv_get_drvdata(device);
601
602 if (stor_device && stor_device->destroy)
603 stor_device = NULL;
604
605 return stor_device;
606 }
607
608
storvsc_wait_to_drain(struct storvsc_device * dev)609 static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
610 {
611 dev->drain_notify = true;
612 wait_event(dev->waiting_to_drain,
613 atomic_read(&dev->num_outstanding_req) == 0);
614 dev->drain_notify = false;
615 }
616
get_in_stor_device(struct hv_device * device)617 static inline struct storvsc_device *get_in_stor_device(
618 struct hv_device *device)
619 {
620 struct storvsc_device *stor_device;
621
622 stor_device = hv_get_drvdata(device);
623
624 if (!stor_device)
625 goto get_in_err;
626
627 /*
628 * If the device is being destroyed; allow incoming
629 * traffic only to cleanup outstanding requests.
630 */
631
632 if (stor_device->destroy &&
633 (atomic_read(&stor_device->num_outstanding_req) == 0))
634 stor_device = NULL;
635
636 get_in_err:
637 return stor_device;
638
639 }
640
storvsc_change_target_cpu(struct vmbus_channel * channel,u32 old,u32 new)641 static void storvsc_change_target_cpu(struct vmbus_channel *channel, u32 old,
642 u32 new)
643 {
644 struct storvsc_device *stor_device;
645 struct vmbus_channel *cur_chn;
646 bool old_is_alloced = false;
647 struct hv_device *device;
648 unsigned long flags;
649 int cpu;
650
651 device = channel->primary_channel ?
652 channel->primary_channel->device_obj
653 : channel->device_obj;
654 stor_device = get_out_stor_device(device);
655 if (!stor_device)
656 return;
657
658 /* See storvsc_do_io() -> get_og_chn(). */
659 spin_lock_irqsave(&stor_device->lock, flags);
660
661 /*
662 * Determines if the storvsc device has other channels assigned to
663 * the "old" CPU to update the alloced_cpus mask and the stor_chns
664 * array.
665 */
666 if (device->channel != channel && device->channel->target_cpu == old) {
667 cur_chn = device->channel;
668 old_is_alloced = true;
669 goto old_is_alloced;
670 }
671 list_for_each_entry(cur_chn, &device->channel->sc_list, sc_list) {
672 if (cur_chn == channel)
673 continue;
674 if (cur_chn->target_cpu == old) {
675 old_is_alloced = true;
676 goto old_is_alloced;
677 }
678 }
679
680 old_is_alloced:
681 if (old_is_alloced)
682 WRITE_ONCE(stor_device->stor_chns[old], cur_chn);
683 else
684 cpumask_clear_cpu(old, &stor_device->alloced_cpus);
685
686 /* "Flush" the stor_chns array. */
687 for_each_possible_cpu(cpu) {
688 if (stor_device->stor_chns[cpu] && !cpumask_test_cpu(
689 cpu, &stor_device->alloced_cpus))
690 WRITE_ONCE(stor_device->stor_chns[cpu], NULL);
691 }
692
693 WRITE_ONCE(stor_device->stor_chns[new], channel);
694 cpumask_set_cpu(new, &stor_device->alloced_cpus);
695
696 spin_unlock_irqrestore(&stor_device->lock, flags);
697 }
698
storvsc_next_request_id(struct vmbus_channel * channel,u64 rqst_addr)699 static u64 storvsc_next_request_id(struct vmbus_channel *channel, u64 rqst_addr)
700 {
701 struct storvsc_cmd_request *request =
702 (struct storvsc_cmd_request *)(unsigned long)rqst_addr;
703
704 if (rqst_addr == VMBUS_RQST_INIT)
705 return VMBUS_RQST_INIT;
706 if (rqst_addr == VMBUS_RQST_RESET)
707 return VMBUS_RQST_RESET;
708
709 /*
710 * Cannot return an ID of 0, which is reserved for an unsolicited
711 * message from Hyper-V.
712 */
713 return (u64)blk_mq_unique_tag(scsi_cmd_to_rq(request->cmd)) + 1;
714 }
715
handle_sc_creation(struct vmbus_channel * new_sc)716 static void handle_sc_creation(struct vmbus_channel *new_sc)
717 {
718 struct hv_device *device = new_sc->primary_channel->device_obj;
719 struct device *dev = &device->device;
720 struct storvsc_device *stor_device;
721 struct vmstorage_channel_properties props;
722 int ret;
723
724 stor_device = get_out_stor_device(device);
725 if (!stor_device)
726 return;
727
728 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
729 new_sc->max_pkt_size = STORVSC_MAX_PKT_SIZE;
730
731 new_sc->next_request_id_callback = storvsc_next_request_id;
732
733 ret = vmbus_open(new_sc,
734 storvsc_ringbuffer_size,
735 storvsc_ringbuffer_size,
736 (void *)&props,
737 sizeof(struct vmstorage_channel_properties),
738 storvsc_on_channel_callback, new_sc);
739
740 /* In case vmbus_open() fails, we don't use the sub-channel. */
741 if (ret != 0) {
742 dev_err(dev, "Failed to open sub-channel: err=%d\n", ret);
743 return;
744 }
745
746 new_sc->change_target_cpu_callback = storvsc_change_target_cpu;
747
748 /* Add the sub-channel to the array of available channels. */
749 stor_device->stor_chns[new_sc->target_cpu] = new_sc;
750 cpumask_set_cpu(new_sc->target_cpu, &stor_device->alloced_cpus);
751 }
752
handle_multichannel_storage(struct hv_device * device,int max_chns)753 static void handle_multichannel_storage(struct hv_device *device, int max_chns)
754 {
755 struct device *dev = &device->device;
756 struct storvsc_device *stor_device;
757 int num_sc;
758 struct storvsc_cmd_request *request;
759 struct vstor_packet *vstor_packet;
760 int ret, t;
761
762 /*
763 * If the number of CPUs is artificially restricted, such as
764 * with maxcpus=1 on the kernel boot line, Hyper-V could offer
765 * sub-channels >= the number of CPUs. These sub-channels
766 * should not be created. The primary channel is already created
767 * and assigned to one CPU, so check against # CPUs - 1.
768 */
769 num_sc = min((int)(num_online_cpus() - 1), max_chns);
770 if (!num_sc)
771 return;
772
773 stor_device = get_out_stor_device(device);
774 if (!stor_device)
775 return;
776
777 stor_device->num_sc = num_sc;
778 request = &stor_device->init_request;
779 vstor_packet = &request->vstor_packet;
780
781 /*
782 * Establish a handler for dealing with subchannels.
783 */
784 vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
785
786 /*
787 * Request the host to create sub-channels.
788 */
789 memset(request, 0, sizeof(struct storvsc_cmd_request));
790 init_completion(&request->wait_event);
791 vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
792 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
793 vstor_packet->sub_channel_count = num_sc;
794
795 ret = vmbus_sendpacket(device->channel, vstor_packet,
796 (sizeof(struct vstor_packet) -
797 stor_device->vmscsi_size_delta),
798 VMBUS_RQST_INIT,
799 VM_PKT_DATA_INBAND,
800 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
801
802 if (ret != 0) {
803 dev_err(dev, "Failed to create sub-channel: err=%d\n", ret);
804 return;
805 }
806
807 t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
808 if (t == 0) {
809 dev_err(dev, "Failed to create sub-channel: timed out\n");
810 return;
811 }
812
813 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
814 vstor_packet->status != 0) {
815 dev_err(dev, "Failed to create sub-channel: op=%d, sts=%d\n",
816 vstor_packet->operation, vstor_packet->status);
817 return;
818 }
819
820 /*
821 * We need to do nothing here, because vmbus_process_offer()
822 * invokes channel->sc_creation_callback, which will open and use
823 * the sub-channel(s).
824 */
825 }
826
cache_wwn(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet)827 static void cache_wwn(struct storvsc_device *stor_device,
828 struct vstor_packet *vstor_packet)
829 {
830 /*
831 * Cache the currently active port and node ww names.
832 */
833 if (vstor_packet->wwn_packet.primary_active) {
834 stor_device->node_name =
835 wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
836 stor_device->port_name =
837 wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
838 } else {
839 stor_device->node_name =
840 wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
841 stor_device->port_name =
842 wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
843 }
844 }
845
846
storvsc_execute_vstor_op(struct hv_device * device,struct storvsc_cmd_request * request,bool status_check)847 static int storvsc_execute_vstor_op(struct hv_device *device,
848 struct storvsc_cmd_request *request,
849 bool status_check)
850 {
851 struct storvsc_device *stor_device;
852 struct vstor_packet *vstor_packet;
853 int ret, t;
854
855 stor_device = get_out_stor_device(device);
856 if (!stor_device)
857 return -ENODEV;
858
859 vstor_packet = &request->vstor_packet;
860
861 init_completion(&request->wait_event);
862 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
863
864 ret = vmbus_sendpacket(device->channel, vstor_packet,
865 (sizeof(struct vstor_packet) -
866 stor_device->vmscsi_size_delta),
867 VMBUS_RQST_INIT,
868 VM_PKT_DATA_INBAND,
869 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
870 if (ret != 0)
871 return ret;
872
873 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
874 if (t == 0)
875 return -ETIMEDOUT;
876
877 if (!status_check)
878 return ret;
879
880 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
881 vstor_packet->status != 0)
882 return -EINVAL;
883
884 return ret;
885 }
886
storvsc_channel_init(struct hv_device * device,bool is_fc)887 static int storvsc_channel_init(struct hv_device *device, bool is_fc)
888 {
889 struct storvsc_device *stor_device;
890 struct storvsc_cmd_request *request;
891 struct vstor_packet *vstor_packet;
892 int ret, i;
893 int max_chns;
894 bool process_sub_channels = false;
895
896 stor_device = get_out_stor_device(device);
897 if (!stor_device)
898 return -ENODEV;
899
900 request = &stor_device->init_request;
901 vstor_packet = &request->vstor_packet;
902
903 /*
904 * Now, initiate the vsc/vsp initialization protocol on the open
905 * channel
906 */
907 memset(request, 0, sizeof(struct storvsc_cmd_request));
908 vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
909 ret = storvsc_execute_vstor_op(device, request, true);
910 if (ret)
911 return ret;
912 /*
913 * Query host supported protocol version.
914 */
915
916 for (i = 0; i < ARRAY_SIZE(vmstor_protocols); i++) {
917 /* reuse the packet for version range supported */
918 memset(vstor_packet, 0, sizeof(struct vstor_packet));
919 vstor_packet->operation =
920 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
921
922 vstor_packet->version.major_minor =
923 vmstor_protocols[i].protocol_version;
924
925 /*
926 * The revision number is only used in Windows; set it to 0.
927 */
928 vstor_packet->version.revision = 0;
929 ret = storvsc_execute_vstor_op(device, request, false);
930 if (ret != 0)
931 return ret;
932
933 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
934 return -EINVAL;
935
936 if (vstor_packet->status == 0) {
937 vmstor_proto_version =
938 vmstor_protocols[i].protocol_version;
939
940 sense_buffer_size =
941 vmstor_protocols[i].sense_buffer_size;
942
943 stor_device->vmscsi_size_delta =
944 vmstor_protocols[i].vmscsi_size_delta;
945
946 break;
947 }
948 }
949
950 if (vstor_packet->status != 0)
951 return -EINVAL;
952
953
954 memset(vstor_packet, 0, sizeof(struct vstor_packet));
955 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
956 ret = storvsc_execute_vstor_op(device, request, true);
957 if (ret != 0)
958 return ret;
959
960 /*
961 * Check to see if multi-channel support is there.
962 * Hosts that implement protocol version of 5.1 and above
963 * support multi-channel.
964 */
965 max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
966
967 /*
968 * Allocate state to manage the sub-channels.
969 * We allocate an array based on the numbers of possible CPUs
970 * (Hyper-V does not support cpu online/offline).
971 * This Array will be sparseley populated with unique
972 * channels - primary + sub-channels.
973 * We will however populate all the slots to evenly distribute
974 * the load.
975 */
976 stor_device->stor_chns = kcalloc(num_possible_cpus(), sizeof(void *),
977 GFP_KERNEL);
978 if (stor_device->stor_chns == NULL)
979 return -ENOMEM;
980
981 device->channel->change_target_cpu_callback = storvsc_change_target_cpu;
982
983 stor_device->stor_chns[device->channel->target_cpu] = device->channel;
984 cpumask_set_cpu(device->channel->target_cpu,
985 &stor_device->alloced_cpus);
986
987 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN8) {
988 if (vstor_packet->storage_channel_properties.flags &
989 STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
990 process_sub_channels = true;
991 }
992 stor_device->max_transfer_bytes =
993 vstor_packet->storage_channel_properties.max_transfer_bytes;
994
995 if (!is_fc)
996 goto done;
997
998 /*
999 * For FC devices retrieve FC HBA data.
1000 */
1001 memset(vstor_packet, 0, sizeof(struct vstor_packet));
1002 vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
1003 ret = storvsc_execute_vstor_op(device, request, true);
1004 if (ret != 0)
1005 return ret;
1006
1007 /*
1008 * Cache the currently active port and node ww names.
1009 */
1010 cache_wwn(stor_device, vstor_packet);
1011
1012 done:
1013
1014 memset(vstor_packet, 0, sizeof(struct vstor_packet));
1015 vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
1016 ret = storvsc_execute_vstor_op(device, request, true);
1017 if (ret != 0)
1018 return ret;
1019
1020 if (process_sub_channels)
1021 handle_multichannel_storage(device, max_chns);
1022
1023 return ret;
1024 }
1025
storvsc_handle_error(struct vmscsi_request * vm_srb,struct scsi_cmnd * scmnd,struct Scsi_Host * host,u8 asc,u8 ascq)1026 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
1027 struct scsi_cmnd *scmnd,
1028 struct Scsi_Host *host,
1029 u8 asc, u8 ascq)
1030 {
1031 struct storvsc_scan_work *wrk;
1032 void (*process_err_fn)(struct work_struct *work);
1033 struct hv_host_device *host_dev = shost_priv(host);
1034
1035 /*
1036 * In some situations, Hyper-V sets multiple bits in the
1037 * srb_status, such as ABORTED and ERROR. So process them
1038 * individually, with the most specific bits first.
1039 */
1040
1041 if (vm_srb->srb_status & SRB_STATUS_INVALID_LUN) {
1042 set_host_byte(scmnd, DID_NO_CONNECT);
1043 process_err_fn = storvsc_remove_lun;
1044 goto do_work;
1045 }
1046
1047 if (vm_srb->srb_status & SRB_STATUS_ABORTED) {
1048 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID &&
1049 /* Capacity data has changed */
1050 (asc == 0x2a) && (ascq == 0x9)) {
1051 process_err_fn = storvsc_device_scan;
1052 /*
1053 * Retry the I/O that triggered this.
1054 */
1055 set_host_byte(scmnd, DID_REQUEUE);
1056 goto do_work;
1057 }
1058 }
1059
1060 if (vm_srb->srb_status & SRB_STATUS_ERROR) {
1061 /*
1062 * Let upper layer deal with error when
1063 * sense message is present.
1064 */
1065 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID)
1066 return;
1067
1068 /*
1069 * If there is an error; offline the device since all
1070 * error recovery strategies would have already been
1071 * deployed on the host side. However, if the command
1072 * were a pass-through command deal with it appropriately.
1073 */
1074 switch (scmnd->cmnd[0]) {
1075 case ATA_16:
1076 case ATA_12:
1077 set_host_byte(scmnd, DID_PASSTHROUGH);
1078 break;
1079 /*
1080 * On some Hyper-V hosts TEST_UNIT_READY command can
1081 * return SRB_STATUS_ERROR. Let the upper level code
1082 * deal with it based on the sense information.
1083 */
1084 case TEST_UNIT_READY:
1085 break;
1086 default:
1087 set_host_byte(scmnd, DID_ERROR);
1088 }
1089 }
1090 return;
1091
1092 do_work:
1093 /*
1094 * We need to schedule work to process this error; schedule it.
1095 */
1096 wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1097 if (!wrk) {
1098 set_host_byte(scmnd, DID_TARGET_FAILURE);
1099 return;
1100 }
1101
1102 wrk->host = host;
1103 wrk->lun = vm_srb->lun;
1104 wrk->tgt_id = vm_srb->target_id;
1105 INIT_WORK(&wrk->work, process_err_fn);
1106 queue_work(host_dev->handle_error_wq, &wrk->work);
1107 }
1108
1109
storvsc_command_completion(struct storvsc_cmd_request * cmd_request,struct storvsc_device * stor_dev)1110 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
1111 struct storvsc_device *stor_dev)
1112 {
1113 struct scsi_cmnd *scmnd = cmd_request->cmd;
1114 struct scsi_sense_hdr sense_hdr;
1115 struct vmscsi_request *vm_srb;
1116 u32 data_transfer_length;
1117 struct Scsi_Host *host;
1118 u32 payload_sz = cmd_request->payload_sz;
1119 void *payload = cmd_request->payload;
1120 bool sense_ok;
1121
1122 host = stor_dev->host;
1123
1124 vm_srb = &cmd_request->vstor_packet.vm_srb;
1125 data_transfer_length = vm_srb->data_transfer_length;
1126
1127 scmnd->result = vm_srb->scsi_status;
1128
1129 if (scmnd->result) {
1130 sense_ok = scsi_normalize_sense(scmnd->sense_buffer,
1131 SCSI_SENSE_BUFFERSIZE, &sense_hdr);
1132
1133 if (sense_ok && do_logging(STORVSC_LOGGING_WARN))
1134 scsi_print_sense_hdr(scmnd->device, "storvsc",
1135 &sense_hdr);
1136 }
1137
1138 if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
1139 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
1140 sense_hdr.ascq);
1141 /*
1142 * The Windows driver set data_transfer_length on
1143 * SRB_STATUS_DATA_OVERRUN. On other errors, this value
1144 * is untouched. In these cases we set it to 0.
1145 */
1146 if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
1147 data_transfer_length = 0;
1148 }
1149
1150 /* Validate data_transfer_length (from Hyper-V) */
1151 if (data_transfer_length > cmd_request->payload->range.len)
1152 data_transfer_length = cmd_request->payload->range.len;
1153
1154 scsi_set_resid(scmnd,
1155 cmd_request->payload->range.len - data_transfer_length);
1156
1157 scmnd->scsi_done(scmnd);
1158
1159 if (payload_sz >
1160 sizeof(struct vmbus_channel_packet_multipage_buffer))
1161 kfree(payload);
1162 }
1163
storvsc_on_io_completion(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet,struct storvsc_cmd_request * request)1164 static void storvsc_on_io_completion(struct storvsc_device *stor_device,
1165 struct vstor_packet *vstor_packet,
1166 struct storvsc_cmd_request *request)
1167 {
1168 struct vstor_packet *stor_pkt;
1169 struct hv_device *device = stor_device->device;
1170
1171 stor_pkt = &request->vstor_packet;
1172
1173 /*
1174 * The current SCSI handling on the host side does
1175 * not correctly handle:
1176 * INQUIRY command with page code parameter set to 0x80
1177 * MODE_SENSE command with cmd[2] == 0x1c
1178 *
1179 * Setup srb and scsi status so this won't be fatal.
1180 * We do this so we can distinguish truly fatal failues
1181 * (srb status == 0x4) and off-line the device in that case.
1182 */
1183
1184 if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1185 (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1186 vstor_packet->vm_srb.scsi_status = 0;
1187 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1188 }
1189
1190 /* Copy over the status...etc */
1191 stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1192 stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1193
1194 /*
1195 * Copy over the sense_info_length, but limit to the known max
1196 * size if Hyper-V returns a bad value.
1197 */
1198 stor_pkt->vm_srb.sense_info_length = min_t(u8, sense_buffer_size,
1199 vstor_packet->vm_srb.sense_info_length);
1200
1201 if (vstor_packet->vm_srb.scsi_status != 0 ||
1202 vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS) {
1203
1204 /*
1205 * Log TEST_UNIT_READY errors only as warnings. Hyper-V can
1206 * return errors when detecting devices using TEST_UNIT_READY,
1207 * and logging these as errors produces unhelpful noise.
1208 */
1209 int loglevel = (stor_pkt->vm_srb.cdb[0] == TEST_UNIT_READY) ?
1210 STORVSC_LOGGING_WARN : STORVSC_LOGGING_ERROR;
1211
1212 storvsc_log(device, loglevel,
1213 "tag#%d cmd 0x%x status: scsi 0x%x srb 0x%x hv 0x%x\n",
1214 scsi_cmd_to_rq(request->cmd)->tag,
1215 stor_pkt->vm_srb.cdb[0],
1216 vstor_packet->vm_srb.scsi_status,
1217 vstor_packet->vm_srb.srb_status,
1218 vstor_packet->status);
1219 }
1220
1221 if (vstor_packet->vm_srb.scsi_status == SAM_STAT_CHECK_CONDITION &&
1222 (vstor_packet->vm_srb.srb_status & SRB_STATUS_AUTOSENSE_VALID))
1223 memcpy(request->cmd->sense_buffer,
1224 vstor_packet->vm_srb.sense_data,
1225 stor_pkt->vm_srb.sense_info_length);
1226
1227 stor_pkt->vm_srb.data_transfer_length =
1228 vstor_packet->vm_srb.data_transfer_length;
1229
1230 storvsc_command_completion(request, stor_device);
1231
1232 if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1233 stor_device->drain_notify)
1234 wake_up(&stor_device->waiting_to_drain);
1235 }
1236
storvsc_on_receive(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet,struct storvsc_cmd_request * request)1237 static void storvsc_on_receive(struct storvsc_device *stor_device,
1238 struct vstor_packet *vstor_packet,
1239 struct storvsc_cmd_request *request)
1240 {
1241 struct hv_host_device *host_dev;
1242 switch (vstor_packet->operation) {
1243 case VSTOR_OPERATION_COMPLETE_IO:
1244 storvsc_on_io_completion(stor_device, vstor_packet, request);
1245 break;
1246
1247 case VSTOR_OPERATION_REMOVE_DEVICE:
1248 case VSTOR_OPERATION_ENUMERATE_BUS:
1249 host_dev = shost_priv(stor_device->host);
1250 queue_work(
1251 host_dev->handle_error_wq, &host_dev->host_scan_work);
1252 break;
1253
1254 case VSTOR_OPERATION_FCHBA_DATA:
1255 cache_wwn(stor_device, vstor_packet);
1256 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1257 fc_host_node_name(stor_device->host) = stor_device->node_name;
1258 fc_host_port_name(stor_device->host) = stor_device->port_name;
1259 #endif
1260 break;
1261 default:
1262 break;
1263 }
1264 }
1265
storvsc_on_channel_callback(void * context)1266 static void storvsc_on_channel_callback(void *context)
1267 {
1268 struct vmbus_channel *channel = (struct vmbus_channel *)context;
1269 const struct vmpacket_descriptor *desc;
1270 struct hv_device *device;
1271 struct storvsc_device *stor_device;
1272 struct Scsi_Host *shost;
1273
1274 if (channel->primary_channel != NULL)
1275 device = channel->primary_channel->device_obj;
1276 else
1277 device = channel->device_obj;
1278
1279 stor_device = get_in_stor_device(device);
1280 if (!stor_device)
1281 return;
1282
1283 shost = stor_device->host;
1284
1285 foreach_vmbus_pkt(desc, channel) {
1286 struct vstor_packet *packet = hv_pkt_data(desc);
1287 struct storvsc_cmd_request *request = NULL;
1288 u32 pktlen = hv_pkt_datalen(desc);
1289 u64 rqst_id = desc->trans_id;
1290 u32 minlen = rqst_id ? sizeof(struct vstor_packet) -
1291 stor_device->vmscsi_size_delta : sizeof(enum vstor_packet_operation);
1292
1293 if (pktlen < minlen) {
1294 dev_err(&device->device,
1295 "Invalid pkt: id=%llu, len=%u, minlen=%u\n",
1296 rqst_id, pktlen, minlen);
1297 continue;
1298 }
1299
1300 if (rqst_id == VMBUS_RQST_INIT) {
1301 request = &stor_device->init_request;
1302 } else if (rqst_id == VMBUS_RQST_RESET) {
1303 request = &stor_device->reset_request;
1304 } else {
1305 /* Hyper-V can send an unsolicited message with ID of 0 */
1306 if (rqst_id == 0) {
1307 /*
1308 * storvsc_on_receive() looks at the vstor_packet in the message
1309 * from the ring buffer.
1310 *
1311 * - If the operation in the vstor_packet is COMPLETE_IO, then
1312 * we call storvsc_on_io_completion(), and dereference the
1313 * guest memory address. Make sure we don't call
1314 * storvsc_on_io_completion() with a guest memory address
1315 * that is zero if Hyper-V were to construct and send such
1316 * a bogus packet.
1317 *
1318 * - If the operation in the vstor_packet is FCHBA_DATA, then
1319 * we call cache_wwn(), and access the data payload area of
1320 * the packet (wwn_packet); however, there is no guarantee
1321 * that the packet is big enough to contain such area.
1322 * Future-proof the code by rejecting such a bogus packet.
1323 */
1324 if (packet->operation == VSTOR_OPERATION_COMPLETE_IO ||
1325 packet->operation == VSTOR_OPERATION_FCHBA_DATA) {
1326 dev_err(&device->device, "Invalid packet with ID of 0\n");
1327 continue;
1328 }
1329 } else {
1330 struct scsi_cmnd *scmnd;
1331
1332 /* Transaction 'rqst_id' corresponds to tag 'rqst_id - 1' */
1333 scmnd = scsi_host_find_tag(shost, rqst_id - 1);
1334 if (scmnd == NULL) {
1335 dev_err(&device->device, "Incorrect transaction ID\n");
1336 continue;
1337 }
1338 request = (struct storvsc_cmd_request *)scsi_cmd_priv(scmnd);
1339 }
1340
1341 storvsc_on_receive(stor_device, packet, request);
1342 continue;
1343 }
1344
1345 memcpy(&request->vstor_packet, packet,
1346 (sizeof(struct vstor_packet) - stor_device->vmscsi_size_delta));
1347 complete(&request->wait_event);
1348 }
1349 }
1350
storvsc_connect_to_vsp(struct hv_device * device,u32 ring_size,bool is_fc)1351 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
1352 bool is_fc)
1353 {
1354 struct vmstorage_channel_properties props;
1355 int ret;
1356
1357 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1358
1359 device->channel->max_pkt_size = STORVSC_MAX_PKT_SIZE;
1360 device->channel->next_request_id_callback = storvsc_next_request_id;
1361
1362 ret = vmbus_open(device->channel,
1363 ring_size,
1364 ring_size,
1365 (void *)&props,
1366 sizeof(struct vmstorage_channel_properties),
1367 storvsc_on_channel_callback, device->channel);
1368
1369 if (ret != 0)
1370 return ret;
1371
1372 ret = storvsc_channel_init(device, is_fc);
1373
1374 return ret;
1375 }
1376
storvsc_dev_remove(struct hv_device * device)1377 static int storvsc_dev_remove(struct hv_device *device)
1378 {
1379 struct storvsc_device *stor_device;
1380
1381 stor_device = hv_get_drvdata(device);
1382
1383 stor_device->destroy = true;
1384
1385 /* Make sure flag is set before waiting */
1386 wmb();
1387
1388 /*
1389 * At this point, all outbound traffic should be disable. We
1390 * only allow inbound traffic (responses) to proceed so that
1391 * outstanding requests can be completed.
1392 */
1393
1394 storvsc_wait_to_drain(stor_device);
1395
1396 /*
1397 * Since we have already drained, we don't need to busy wait
1398 * as was done in final_release_stor_device()
1399 * Note that we cannot set the ext pointer to NULL until
1400 * we have drained - to drain the outgoing packets, we need to
1401 * allow incoming packets.
1402 */
1403 hv_set_drvdata(device, NULL);
1404
1405 /* Close the channel */
1406 vmbus_close(device->channel);
1407
1408 kfree(stor_device->stor_chns);
1409 kfree(stor_device);
1410 return 0;
1411 }
1412
get_og_chn(struct storvsc_device * stor_device,u16 q_num)1413 static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device,
1414 u16 q_num)
1415 {
1416 u16 slot = 0;
1417 u16 hash_qnum;
1418 const struct cpumask *node_mask;
1419 int num_channels, tgt_cpu;
1420
1421 if (stor_device->num_sc == 0) {
1422 stor_device->stor_chns[q_num] = stor_device->device->channel;
1423 return stor_device->device->channel;
1424 }
1425
1426 /*
1427 * Our channel array is sparsley populated and we
1428 * initiated I/O on a processor/hw-q that does not
1429 * currently have a designated channel. Fix this.
1430 * The strategy is simple:
1431 * I. Ensure NUMA locality
1432 * II. Distribute evenly (best effort)
1433 */
1434
1435 node_mask = cpumask_of_node(cpu_to_node(q_num));
1436
1437 num_channels = 0;
1438 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1439 if (cpumask_test_cpu(tgt_cpu, node_mask))
1440 num_channels++;
1441 }
1442 if (num_channels == 0) {
1443 stor_device->stor_chns[q_num] = stor_device->device->channel;
1444 return stor_device->device->channel;
1445 }
1446
1447 hash_qnum = q_num;
1448 while (hash_qnum >= num_channels)
1449 hash_qnum -= num_channels;
1450
1451 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1452 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1453 continue;
1454 if (slot == hash_qnum)
1455 break;
1456 slot++;
1457 }
1458
1459 stor_device->stor_chns[q_num] = stor_device->stor_chns[tgt_cpu];
1460
1461 return stor_device->stor_chns[q_num];
1462 }
1463
1464
storvsc_do_io(struct hv_device * device,struct storvsc_cmd_request * request,u16 q_num)1465 static int storvsc_do_io(struct hv_device *device,
1466 struct storvsc_cmd_request *request, u16 q_num)
1467 {
1468 struct storvsc_device *stor_device;
1469 struct vstor_packet *vstor_packet;
1470 struct vmbus_channel *outgoing_channel, *channel;
1471 unsigned long flags;
1472 int ret = 0;
1473 const struct cpumask *node_mask;
1474 int tgt_cpu;
1475
1476 vstor_packet = &request->vstor_packet;
1477 stor_device = get_out_stor_device(device);
1478
1479 if (!stor_device)
1480 return -ENODEV;
1481
1482
1483 request->device = device;
1484 /*
1485 * Select an appropriate channel to send the request out.
1486 */
1487 /* See storvsc_change_target_cpu(). */
1488 outgoing_channel = READ_ONCE(stor_device->stor_chns[q_num]);
1489 if (outgoing_channel != NULL) {
1490 if (outgoing_channel->target_cpu == q_num) {
1491 /*
1492 * Ideally, we want to pick a different channel if
1493 * available on the same NUMA node.
1494 */
1495 node_mask = cpumask_of_node(cpu_to_node(q_num));
1496 for_each_cpu_wrap(tgt_cpu,
1497 &stor_device->alloced_cpus, q_num + 1) {
1498 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1499 continue;
1500 if (tgt_cpu == q_num)
1501 continue;
1502 channel = READ_ONCE(
1503 stor_device->stor_chns[tgt_cpu]);
1504 if (channel == NULL)
1505 continue;
1506 if (hv_get_avail_to_write_percent(
1507 &channel->outbound)
1508 > ring_avail_percent_lowater) {
1509 outgoing_channel = channel;
1510 goto found_channel;
1511 }
1512 }
1513
1514 /*
1515 * All the other channels on the same NUMA node are
1516 * busy. Try to use the channel on the current CPU
1517 */
1518 if (hv_get_avail_to_write_percent(
1519 &outgoing_channel->outbound)
1520 > ring_avail_percent_lowater)
1521 goto found_channel;
1522
1523 /*
1524 * If we reach here, all the channels on the current
1525 * NUMA node are busy. Try to find a channel in
1526 * other NUMA nodes
1527 */
1528 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1529 if (cpumask_test_cpu(tgt_cpu, node_mask))
1530 continue;
1531 channel = READ_ONCE(
1532 stor_device->stor_chns[tgt_cpu]);
1533 if (channel == NULL)
1534 continue;
1535 if (hv_get_avail_to_write_percent(
1536 &channel->outbound)
1537 > ring_avail_percent_lowater) {
1538 outgoing_channel = channel;
1539 goto found_channel;
1540 }
1541 }
1542 }
1543 } else {
1544 spin_lock_irqsave(&stor_device->lock, flags);
1545 outgoing_channel = stor_device->stor_chns[q_num];
1546 if (outgoing_channel != NULL) {
1547 spin_unlock_irqrestore(&stor_device->lock, flags);
1548 goto found_channel;
1549 }
1550 outgoing_channel = get_og_chn(stor_device, q_num);
1551 spin_unlock_irqrestore(&stor_device->lock, flags);
1552 }
1553
1554 found_channel:
1555 vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1556
1557 vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) -
1558 stor_device->vmscsi_size_delta);
1559
1560
1561 vstor_packet->vm_srb.sense_info_length = sense_buffer_size;
1562
1563
1564 vstor_packet->vm_srb.data_transfer_length =
1565 request->payload->range.len;
1566
1567 vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1568
1569 if (request->payload->range.len) {
1570
1571 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1572 request->payload, request->payload_sz,
1573 vstor_packet,
1574 (sizeof(struct vstor_packet) -
1575 stor_device->vmscsi_size_delta),
1576 (unsigned long)request);
1577 } else {
1578 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1579 (sizeof(struct vstor_packet) -
1580 stor_device->vmscsi_size_delta),
1581 (unsigned long)request,
1582 VM_PKT_DATA_INBAND,
1583 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1584 }
1585
1586 if (ret != 0)
1587 return ret;
1588
1589 atomic_inc(&stor_device->num_outstanding_req);
1590
1591 return ret;
1592 }
1593
storvsc_device_alloc(struct scsi_device * sdevice)1594 static int storvsc_device_alloc(struct scsi_device *sdevice)
1595 {
1596 /*
1597 * Set blist flag to permit the reading of the VPD pages even when
1598 * the target may claim SPC-2 compliance. MSFT targets currently
1599 * claim SPC-2 compliance while they implement post SPC-2 features.
1600 * With this flag we can correctly handle WRITE_SAME_16 issues.
1601 *
1602 * Hypervisor reports SCSI_UNKNOWN type for DVD ROM device but
1603 * still supports REPORT LUN.
1604 */
1605 sdevice->sdev_bflags = BLIST_REPORTLUN2 | BLIST_TRY_VPD_PAGES;
1606
1607 return 0;
1608 }
1609
storvsc_device_configure(struct scsi_device * sdevice)1610 static int storvsc_device_configure(struct scsi_device *sdevice)
1611 {
1612 blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1613
1614 sdevice->no_write_same = 1;
1615
1616 /*
1617 * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1618 * if the device is a MSFT virtual device. If the host is
1619 * WIN10 or newer, allow write_same.
1620 */
1621 if (!strncmp(sdevice->vendor, "Msft", 4)) {
1622 switch (vmstor_proto_version) {
1623 case VMSTOR_PROTO_VERSION_WIN8:
1624 case VMSTOR_PROTO_VERSION_WIN8_1:
1625 sdevice->scsi_level = SCSI_SPC_3;
1626 break;
1627 }
1628
1629 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1630 sdevice->no_write_same = 0;
1631 }
1632
1633 return 0;
1634 }
1635
storvsc_get_chs(struct scsi_device * sdev,struct block_device * bdev,sector_t capacity,int * info)1636 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1637 sector_t capacity, int *info)
1638 {
1639 sector_t nsect = capacity;
1640 sector_t cylinders = nsect;
1641 int heads, sectors_pt;
1642
1643 /*
1644 * We are making up these values; let us keep it simple.
1645 */
1646 heads = 0xff;
1647 sectors_pt = 0x3f; /* Sectors per track */
1648 sector_div(cylinders, heads * sectors_pt);
1649 if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1650 cylinders = 0xffff;
1651
1652 info[0] = heads;
1653 info[1] = sectors_pt;
1654 info[2] = (int)cylinders;
1655
1656 return 0;
1657 }
1658
storvsc_host_reset_handler(struct scsi_cmnd * scmnd)1659 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1660 {
1661 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1662 struct hv_device *device = host_dev->dev;
1663
1664 struct storvsc_device *stor_device;
1665 struct storvsc_cmd_request *request;
1666 struct vstor_packet *vstor_packet;
1667 int ret, t;
1668
1669 stor_device = get_out_stor_device(device);
1670 if (!stor_device)
1671 return FAILED;
1672
1673 request = &stor_device->reset_request;
1674 vstor_packet = &request->vstor_packet;
1675 memset(vstor_packet, 0, sizeof(struct vstor_packet));
1676
1677 init_completion(&request->wait_event);
1678
1679 vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1680 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1681 vstor_packet->vm_srb.path_id = stor_device->path_id;
1682
1683 ret = vmbus_sendpacket(device->channel, vstor_packet,
1684 (sizeof(struct vstor_packet) -
1685 stor_device->vmscsi_size_delta),
1686 VMBUS_RQST_RESET,
1687 VM_PKT_DATA_INBAND,
1688 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1689 if (ret != 0)
1690 return FAILED;
1691
1692 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1693 if (t == 0)
1694 return TIMEOUT_ERROR;
1695
1696
1697 /*
1698 * At this point, all outstanding requests in the adapter
1699 * should have been flushed out and return to us
1700 * There is a potential race here where the host may be in
1701 * the process of responding when we return from here.
1702 * Just wait for all in-transit packets to be accounted for
1703 * before we return from here.
1704 */
1705 storvsc_wait_to_drain(stor_device);
1706
1707 return SUCCESS;
1708 }
1709
1710 /*
1711 * The host guarantees to respond to each command, although I/O latencies might
1712 * be unbounded on Azure. Reset the timer unconditionally to give the host a
1713 * chance to perform EH.
1714 */
storvsc_eh_timed_out(struct scsi_cmnd * scmnd)1715 static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1716 {
1717 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1718 if (scmnd->device->host->transportt == fc_transport_template)
1719 return fc_eh_timed_out(scmnd);
1720 #endif
1721 return BLK_EH_RESET_TIMER;
1722 }
1723
storvsc_scsi_cmd_ok(struct scsi_cmnd * scmnd)1724 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1725 {
1726 bool allowed = true;
1727 u8 scsi_op = scmnd->cmnd[0];
1728
1729 switch (scsi_op) {
1730 /* the host does not handle WRITE_SAME, log accident usage */
1731 case WRITE_SAME:
1732 /*
1733 * smartd sends this command and the host does not handle
1734 * this. So, don't send it.
1735 */
1736 case SET_WINDOW:
1737 set_host_byte(scmnd, DID_ERROR);
1738 allowed = false;
1739 break;
1740 default:
1741 break;
1742 }
1743 return allowed;
1744 }
1745
storvsc_queuecommand(struct Scsi_Host * host,struct scsi_cmnd * scmnd)1746 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1747 {
1748 int ret;
1749 struct hv_host_device *host_dev = shost_priv(host);
1750 struct hv_device *dev = host_dev->dev;
1751 struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1752 int i;
1753 struct scatterlist *sgl;
1754 unsigned int sg_count;
1755 struct vmscsi_request *vm_srb;
1756 struct vmbus_packet_mpb_array *payload;
1757 u32 payload_sz;
1758 u32 length;
1759
1760 if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1761 /*
1762 * On legacy hosts filter unimplemented commands.
1763 * Future hosts are expected to correctly handle
1764 * unsupported commands. Furthermore, it is
1765 * possible that some of the currently
1766 * unsupported commands maybe supported in
1767 * future versions of the host.
1768 */
1769 if (!storvsc_scsi_cmd_ok(scmnd)) {
1770 scmnd->scsi_done(scmnd);
1771 return 0;
1772 }
1773 }
1774
1775 /* Setup the cmd request */
1776 cmd_request->cmd = scmnd;
1777
1778 memset(&cmd_request->vstor_packet, 0, sizeof(struct vstor_packet));
1779 vm_srb = &cmd_request->vstor_packet.vm_srb;
1780 vm_srb->win8_extension.time_out_value = 60;
1781
1782 vm_srb->win8_extension.srb_flags |=
1783 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1784
1785 if (scmnd->device->tagged_supported) {
1786 vm_srb->win8_extension.srb_flags |=
1787 (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
1788 vm_srb->win8_extension.queue_tag = SP_UNTAGGED;
1789 vm_srb->win8_extension.queue_action = SRB_SIMPLE_TAG_REQUEST;
1790 }
1791
1792 /* Build the SRB */
1793 switch (scmnd->sc_data_direction) {
1794 case DMA_TO_DEVICE:
1795 vm_srb->data_in = WRITE_TYPE;
1796 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_OUT;
1797 break;
1798 case DMA_FROM_DEVICE:
1799 vm_srb->data_in = READ_TYPE;
1800 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_IN;
1801 break;
1802 case DMA_NONE:
1803 vm_srb->data_in = UNKNOWN_TYPE;
1804 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1805 break;
1806 default:
1807 /*
1808 * This is DMA_BIDIRECTIONAL or something else we are never
1809 * supposed to see here.
1810 */
1811 WARN(1, "Unexpected data direction: %d\n",
1812 scmnd->sc_data_direction);
1813 return -EINVAL;
1814 }
1815
1816
1817 vm_srb->port_number = host_dev->port;
1818 vm_srb->path_id = scmnd->device->channel;
1819 vm_srb->target_id = scmnd->device->id;
1820 vm_srb->lun = scmnd->device->lun;
1821
1822 vm_srb->cdb_length = scmnd->cmd_len;
1823
1824 memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1825
1826 sgl = (struct scatterlist *)scsi_sglist(scmnd);
1827 sg_count = scsi_sg_count(scmnd);
1828
1829 length = scsi_bufflen(scmnd);
1830 payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1831 payload_sz = sizeof(cmd_request->mpb);
1832
1833 if (sg_count) {
1834 unsigned int hvpgoff, hvpfns_to_add;
1835 unsigned long offset_in_hvpg = offset_in_hvpage(sgl->offset);
1836 unsigned int hvpg_count = HVPFN_UP(offset_in_hvpg + length);
1837 u64 hvpfn;
1838
1839 if (hvpg_count > MAX_PAGE_BUFFER_COUNT) {
1840
1841 payload_sz = (hvpg_count * sizeof(u64) +
1842 sizeof(struct vmbus_packet_mpb_array));
1843 payload = kzalloc(payload_sz, GFP_ATOMIC);
1844 if (!payload)
1845 return SCSI_MLQUEUE_DEVICE_BUSY;
1846 }
1847
1848 payload->range.len = length;
1849 payload->range.offset = offset_in_hvpg;
1850
1851
1852 for (i = 0; sgl != NULL; sgl = sg_next(sgl)) {
1853 /*
1854 * Init values for the current sgl entry. hvpgoff
1855 * and hvpfns_to_add are in units of Hyper-V size
1856 * pages. Handling the PAGE_SIZE != HV_HYP_PAGE_SIZE
1857 * case also handles values of sgl->offset that are
1858 * larger than PAGE_SIZE. Such offsets are handled
1859 * even on other than the first sgl entry, provided
1860 * they are a multiple of PAGE_SIZE.
1861 */
1862 hvpgoff = HVPFN_DOWN(sgl->offset);
1863 hvpfn = page_to_hvpfn(sg_page(sgl)) + hvpgoff;
1864 hvpfns_to_add = HVPFN_UP(sgl->offset + sgl->length) -
1865 hvpgoff;
1866
1867 /*
1868 * Fill the next portion of the PFN array with
1869 * sequential Hyper-V PFNs for the continguous physical
1870 * memory described by the sgl entry. The end of the
1871 * last sgl should be reached at the same time that
1872 * the PFN array is filled.
1873 */
1874 while (hvpfns_to_add--)
1875 payload->range.pfn_array[i++] = hvpfn++;
1876 }
1877 }
1878
1879 cmd_request->payload = payload;
1880 cmd_request->payload_sz = payload_sz;
1881
1882 /* Invokes the vsc to start an IO */
1883 ret = storvsc_do_io(dev, cmd_request, get_cpu());
1884 put_cpu();
1885
1886 if (ret == -EAGAIN) {
1887 if (payload_sz > sizeof(cmd_request->mpb))
1888 kfree(payload);
1889 /* no more space */
1890 return SCSI_MLQUEUE_DEVICE_BUSY;
1891 }
1892
1893 return 0;
1894 }
1895
1896 static struct scsi_host_template scsi_driver = {
1897 .module = THIS_MODULE,
1898 .name = "storvsc_host_t",
1899 .cmd_size = sizeof(struct storvsc_cmd_request),
1900 .bios_param = storvsc_get_chs,
1901 .queuecommand = storvsc_queuecommand,
1902 .eh_host_reset_handler = storvsc_host_reset_handler,
1903 .proc_name = "storvsc_host",
1904 .eh_timed_out = storvsc_eh_timed_out,
1905 .slave_alloc = storvsc_device_alloc,
1906 .slave_configure = storvsc_device_configure,
1907 .cmd_per_lun = 2048,
1908 .this_id = -1,
1909 /* Ensure there are no gaps in presented sgls */
1910 .virt_boundary_mask = PAGE_SIZE-1,
1911 .no_write_same = 1,
1912 .track_queue_depth = 1,
1913 .change_queue_depth = storvsc_change_queue_depth,
1914 };
1915
1916 enum {
1917 SCSI_GUID,
1918 IDE_GUID,
1919 SFC_GUID,
1920 };
1921
1922 static const struct hv_vmbus_device_id id_table[] = {
1923 /* SCSI guid */
1924 { HV_SCSI_GUID,
1925 .driver_data = SCSI_GUID
1926 },
1927 /* IDE guid */
1928 { HV_IDE_GUID,
1929 .driver_data = IDE_GUID
1930 },
1931 /* Fibre Channel GUID */
1932 {
1933 HV_SYNTHFC_GUID,
1934 .driver_data = SFC_GUID
1935 },
1936 { },
1937 };
1938
1939 MODULE_DEVICE_TABLE(vmbus, id_table);
1940
1941 static const struct { guid_t guid; } fc_guid = { HV_SYNTHFC_GUID };
1942
hv_dev_is_fc(struct hv_device * hv_dev)1943 static bool hv_dev_is_fc(struct hv_device *hv_dev)
1944 {
1945 return guid_equal(&fc_guid.guid, &hv_dev->dev_type);
1946 }
1947
storvsc_probe(struct hv_device * device,const struct hv_vmbus_device_id * dev_id)1948 static int storvsc_probe(struct hv_device *device,
1949 const struct hv_vmbus_device_id *dev_id)
1950 {
1951 int ret;
1952 int num_cpus = num_online_cpus();
1953 int num_present_cpus = num_present_cpus();
1954 struct Scsi_Host *host;
1955 struct hv_host_device *host_dev;
1956 bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1957 bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
1958 int target = 0;
1959 struct storvsc_device *stor_device;
1960 int max_luns_per_target;
1961 int max_targets;
1962 int max_channels;
1963 int max_sub_channels = 0;
1964
1965 /*
1966 * Based on the windows host we are running on,
1967 * set state to properly communicate with the host.
1968 */
1969
1970 if (vmbus_proto_version < VERSION_WIN8) {
1971 max_luns_per_target = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1972 max_targets = STORVSC_IDE_MAX_TARGETS;
1973 max_channels = STORVSC_IDE_MAX_CHANNELS;
1974 } else {
1975 max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET;
1976 max_targets = STORVSC_MAX_TARGETS;
1977 max_channels = STORVSC_MAX_CHANNELS;
1978 /*
1979 * On Windows8 and above, we support sub-channels for storage
1980 * on SCSI and FC controllers.
1981 * The number of sub-channels offerred is based on the number of
1982 * VCPUs in the guest.
1983 */
1984 if (!dev_is_ide)
1985 max_sub_channels =
1986 (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
1987 }
1988
1989 scsi_driver.can_queue = max_outstanding_req_per_channel *
1990 (max_sub_channels + 1) *
1991 (100 - ring_avail_percent_lowater) / 100;
1992
1993 host = scsi_host_alloc(&scsi_driver,
1994 sizeof(struct hv_host_device));
1995 if (!host)
1996 return -ENOMEM;
1997
1998 host_dev = shost_priv(host);
1999 memset(host_dev, 0, sizeof(struct hv_host_device));
2000
2001 host_dev->port = host->host_no;
2002 host_dev->dev = device;
2003 host_dev->host = host;
2004
2005
2006 stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
2007 if (!stor_device) {
2008 ret = -ENOMEM;
2009 goto err_out0;
2010 }
2011
2012 stor_device->destroy = false;
2013 init_waitqueue_head(&stor_device->waiting_to_drain);
2014 stor_device->device = device;
2015 stor_device->host = host;
2016 stor_device->vmscsi_size_delta = sizeof(struct vmscsi_win8_extension);
2017 spin_lock_init(&stor_device->lock);
2018 hv_set_drvdata(device, stor_device);
2019
2020 stor_device->port_number = host->host_no;
2021 ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size, is_fc);
2022 if (ret)
2023 goto err_out1;
2024
2025 host_dev->path = stor_device->path_id;
2026 host_dev->target = stor_device->target_id;
2027
2028 switch (dev_id->driver_data) {
2029 case SFC_GUID:
2030 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
2031 host->max_id = STORVSC_FC_MAX_TARGETS;
2032 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
2033 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2034 host->transportt = fc_transport_template;
2035 #endif
2036 break;
2037
2038 case SCSI_GUID:
2039 host->max_lun = max_luns_per_target;
2040 host->max_id = max_targets;
2041 host->max_channel = max_channels - 1;
2042 break;
2043
2044 default:
2045 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
2046 host->max_id = STORVSC_IDE_MAX_TARGETS;
2047 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
2048 break;
2049 }
2050 /* max cmd length */
2051 host->max_cmd_len = STORVSC_MAX_CMD_LEN;
2052
2053 /*
2054 * set the table size based on the info we got
2055 * from the host.
2056 */
2057 host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
2058 /*
2059 * For non-IDE disks, the host supports multiple channels.
2060 * Set the number of HW queues we are supporting.
2061 */
2062 if (!dev_is_ide) {
2063 if (storvsc_max_hw_queues > num_present_cpus) {
2064 storvsc_max_hw_queues = 0;
2065 storvsc_log(device, STORVSC_LOGGING_WARN,
2066 "Resetting invalid storvsc_max_hw_queues value to default.\n");
2067 }
2068 if (storvsc_max_hw_queues)
2069 host->nr_hw_queues = storvsc_max_hw_queues;
2070 else
2071 host->nr_hw_queues = num_present_cpus;
2072 }
2073
2074 /*
2075 * Set the error handler work queue.
2076 */
2077 host_dev->handle_error_wq =
2078 alloc_ordered_workqueue("storvsc_error_wq_%d",
2079 WQ_MEM_RECLAIM,
2080 host->host_no);
2081 if (!host_dev->handle_error_wq) {
2082 ret = -ENOMEM;
2083 goto err_out2;
2084 }
2085 INIT_WORK(&host_dev->host_scan_work, storvsc_host_scan);
2086 /* Register the HBA and start the scsi bus scan */
2087 ret = scsi_add_host(host, &device->device);
2088 if (ret != 0)
2089 goto err_out3;
2090
2091 if (!dev_is_ide) {
2092 scsi_scan_host(host);
2093 } else {
2094 target = (device->dev_instance.b[5] << 8 |
2095 device->dev_instance.b[4]);
2096 ret = scsi_add_device(host, 0, target, 0);
2097 if (ret)
2098 goto err_out4;
2099 }
2100 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2101 if (host->transportt == fc_transport_template) {
2102 struct fc_rport_identifiers ids = {
2103 .roles = FC_PORT_ROLE_FCP_DUMMY_INITIATOR,
2104 };
2105
2106 fc_host_node_name(host) = stor_device->node_name;
2107 fc_host_port_name(host) = stor_device->port_name;
2108 stor_device->rport = fc_remote_port_add(host, 0, &ids);
2109 if (!stor_device->rport) {
2110 ret = -ENOMEM;
2111 goto err_out4;
2112 }
2113 }
2114 #endif
2115 return 0;
2116
2117 err_out4:
2118 scsi_remove_host(host);
2119
2120 err_out3:
2121 destroy_workqueue(host_dev->handle_error_wq);
2122
2123 err_out2:
2124 /*
2125 * Once we have connected with the host, we would need to
2126 * to invoke storvsc_dev_remove() to rollback this state and
2127 * this call also frees up the stor_device; hence the jump around
2128 * err_out1 label.
2129 */
2130 storvsc_dev_remove(device);
2131 goto err_out0;
2132
2133 err_out1:
2134 kfree(stor_device->stor_chns);
2135 kfree(stor_device);
2136
2137 err_out0:
2138 scsi_host_put(host);
2139 return ret;
2140 }
2141
2142 /* Change a scsi target's queue depth */
storvsc_change_queue_depth(struct scsi_device * sdev,int queue_depth)2143 static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth)
2144 {
2145 if (queue_depth > scsi_driver.can_queue)
2146 queue_depth = scsi_driver.can_queue;
2147
2148 return scsi_change_queue_depth(sdev, queue_depth);
2149 }
2150
storvsc_remove(struct hv_device * dev)2151 static int storvsc_remove(struct hv_device *dev)
2152 {
2153 struct storvsc_device *stor_device = hv_get_drvdata(dev);
2154 struct Scsi_Host *host = stor_device->host;
2155 struct hv_host_device *host_dev = shost_priv(host);
2156
2157 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2158 if (host->transportt == fc_transport_template) {
2159 fc_remote_port_delete(stor_device->rport);
2160 fc_remove_host(host);
2161 }
2162 #endif
2163 destroy_workqueue(host_dev->handle_error_wq);
2164 scsi_remove_host(host);
2165 storvsc_dev_remove(dev);
2166 scsi_host_put(host);
2167
2168 return 0;
2169 }
2170
storvsc_suspend(struct hv_device * hv_dev)2171 static int storvsc_suspend(struct hv_device *hv_dev)
2172 {
2173 struct storvsc_device *stor_device = hv_get_drvdata(hv_dev);
2174 struct Scsi_Host *host = stor_device->host;
2175 struct hv_host_device *host_dev = shost_priv(host);
2176
2177 storvsc_wait_to_drain(stor_device);
2178
2179 drain_workqueue(host_dev->handle_error_wq);
2180
2181 vmbus_close(hv_dev->channel);
2182
2183 kfree(stor_device->stor_chns);
2184 stor_device->stor_chns = NULL;
2185
2186 cpumask_clear(&stor_device->alloced_cpus);
2187
2188 return 0;
2189 }
2190
storvsc_resume(struct hv_device * hv_dev)2191 static int storvsc_resume(struct hv_device *hv_dev)
2192 {
2193 int ret;
2194
2195 ret = storvsc_connect_to_vsp(hv_dev, storvsc_ringbuffer_size,
2196 hv_dev_is_fc(hv_dev));
2197 return ret;
2198 }
2199
2200 static struct hv_driver storvsc_drv = {
2201 .name = KBUILD_MODNAME,
2202 .id_table = id_table,
2203 .probe = storvsc_probe,
2204 .remove = storvsc_remove,
2205 .suspend = storvsc_suspend,
2206 .resume = storvsc_resume,
2207 .driver = {
2208 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
2209 },
2210 };
2211
2212 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2213 static struct fc_function_template fc_transport_functions = {
2214 .show_host_node_name = 1,
2215 .show_host_port_name = 1,
2216 };
2217 #endif
2218
storvsc_drv_init(void)2219 static int __init storvsc_drv_init(void)
2220 {
2221 int ret;
2222
2223 /*
2224 * Divide the ring buffer data size (which is 1 page less
2225 * than the ring buffer size since that page is reserved for
2226 * the ring buffer indices) by the max request size (which is
2227 * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
2228 *
2229 * The computation underestimates max_outstanding_req_per_channel
2230 * for Win7 and older hosts because it does not take into account
2231 * the vmscsi_size_delta correction to the max request size.
2232 */
2233 max_outstanding_req_per_channel =
2234 ((storvsc_ringbuffer_size - PAGE_SIZE) /
2235 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
2236 sizeof(struct vstor_packet) + sizeof(u64),
2237 sizeof(u64)));
2238
2239 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2240 fc_transport_template = fc_attach_transport(&fc_transport_functions);
2241 if (!fc_transport_template)
2242 return -ENODEV;
2243 #endif
2244
2245 ret = vmbus_driver_register(&storvsc_drv);
2246
2247 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2248 if (ret)
2249 fc_release_transport(fc_transport_template);
2250 #endif
2251
2252 return ret;
2253 }
2254
storvsc_drv_exit(void)2255 static void __exit storvsc_drv_exit(void)
2256 {
2257 vmbus_driver_unregister(&storvsc_drv);
2258 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2259 fc_release_transport(fc_transport_template);
2260 #endif
2261 }
2262
2263 MODULE_LICENSE("GPL");
2264 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
2265 module_init(storvsc_drv_init);
2266 module_exit(storvsc_drv_exit);
2267
