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 <linux/dma-mapping.h>
25
26 #include <scsi/scsi.h>
27 #include <scsi/scsi_cmnd.h>
28 #include <scsi/scsi_host.h>
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_tcq.h>
31 #include <scsi/scsi_eh.h>
32 #include <scsi/scsi_devinfo.h>
33 #include <scsi/scsi_dbg.h>
34 #include <scsi/scsi_transport_fc.h>
35 #include <scsi/scsi_transport.h>
36
37 /*
38 * All wire protocol details (storage protocol between the guest and the host)
39 * are consolidated here.
40 *
41 * Begin protocol definitions.
42 */
43
44 /*
45 * Version history:
46 * V1 Beta: 0.1
47 * V1 RC < 2008/1/31: 1.0
48 * V1 RC > 2008/1/31: 2.0
49 * Win7: 4.2
50 * Win8: 5.1
51 * Win8.1: 6.0
52 * Win10: 6.2
53 */
54
55 #define VMSTOR_PROTO_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
56 (((MINOR_) & 0xff)))
57 #define VMSTOR_PROTO_VERSION_WIN6 VMSTOR_PROTO_VERSION(2, 0)
58 #define VMSTOR_PROTO_VERSION_WIN7 VMSTOR_PROTO_VERSION(4, 2)
59 #define VMSTOR_PROTO_VERSION_WIN8 VMSTOR_PROTO_VERSION(5, 1)
60 #define VMSTOR_PROTO_VERSION_WIN8_1 VMSTOR_PROTO_VERSION(6, 0)
61 #define VMSTOR_PROTO_VERSION_WIN10 VMSTOR_PROTO_VERSION(6, 2)
62
63 /* channel callback timeout in ms */
64 #define CALLBACK_TIMEOUT 2
65
66 /* Packet structure describing virtual storage requests. */
67 enum vstor_packet_operation {
68 VSTOR_OPERATION_COMPLETE_IO = 1,
69 VSTOR_OPERATION_REMOVE_DEVICE = 2,
70 VSTOR_OPERATION_EXECUTE_SRB = 3,
71 VSTOR_OPERATION_RESET_LUN = 4,
72 VSTOR_OPERATION_RESET_ADAPTER = 5,
73 VSTOR_OPERATION_RESET_BUS = 6,
74 VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
75 VSTOR_OPERATION_END_INITIALIZATION = 8,
76 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
77 VSTOR_OPERATION_QUERY_PROPERTIES = 10,
78 VSTOR_OPERATION_ENUMERATE_BUS = 11,
79 VSTOR_OPERATION_FCHBA_DATA = 12,
80 VSTOR_OPERATION_CREATE_SUB_CHANNELS = 13,
81 VSTOR_OPERATION_MAXIMUM = 13
82 };
83
84 /*
85 * WWN packet for Fibre Channel HBA
86 */
87
88 struct hv_fc_wwn_packet {
89 u8 primary_active;
90 u8 reserved1[3];
91 u8 primary_port_wwn[8];
92 u8 primary_node_wwn[8];
93 u8 secondary_port_wwn[8];
94 u8 secondary_node_wwn[8];
95 };
96
97
98
99 /*
100 * SRB Flag Bits
101 */
102
103 #define SRB_FLAGS_QUEUE_ACTION_ENABLE 0x00000002
104 #define SRB_FLAGS_DISABLE_DISCONNECT 0x00000004
105 #define SRB_FLAGS_DISABLE_SYNCH_TRANSFER 0x00000008
106 #define SRB_FLAGS_BYPASS_FROZEN_QUEUE 0x00000010
107 #define SRB_FLAGS_DISABLE_AUTOSENSE 0x00000020
108 #define SRB_FLAGS_DATA_IN 0x00000040
109 #define SRB_FLAGS_DATA_OUT 0x00000080
110 #define SRB_FLAGS_NO_DATA_TRANSFER 0x00000000
111 #define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT)
112 #define SRB_FLAGS_NO_QUEUE_FREEZE 0x00000100
113 #define SRB_FLAGS_ADAPTER_CACHE_ENABLE 0x00000200
114 #define SRB_FLAGS_FREE_SENSE_BUFFER 0x00000400
115
116 /*
117 * This flag indicates the request is part of the workflow for processing a D3.
118 */
119 #define SRB_FLAGS_D3_PROCESSING 0x00000800
120 #define SRB_FLAGS_IS_ACTIVE 0x00010000
121 #define SRB_FLAGS_ALLOCATED_FROM_ZONE 0x00020000
122 #define SRB_FLAGS_SGLIST_FROM_POOL 0x00040000
123 #define SRB_FLAGS_BYPASS_LOCKED_QUEUE 0x00080000
124 #define SRB_FLAGS_NO_KEEP_AWAKE 0x00100000
125 #define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE 0x00200000
126 #define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT 0x00400000
127 #define SRB_FLAGS_DONT_START_NEXT_PACKET 0x00800000
128 #define SRB_FLAGS_PORT_DRIVER_RESERVED 0x0F000000
129 #define SRB_FLAGS_CLASS_DRIVER_RESERVED 0xF0000000
130
131 #define SP_UNTAGGED ((unsigned char) ~0)
132 #define SRB_SIMPLE_TAG_REQUEST 0x20
133
134 /*
135 * Platform neutral description of a scsi request -
136 * this remains the same across the write regardless of 32/64 bit
137 * note: it's patterned off the SCSI_PASS_THROUGH structure
138 */
139 #define STORVSC_MAX_CMD_LEN 0x10
140
141 /* Sense buffer size is the same for all versions since Windows 8 */
142 #define STORVSC_SENSE_BUFFER_SIZE 0x14
143 #define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14
144
145 /*
146 * The storage protocol version is determined during the
147 * initial exchange with the host. It will indicate which
148 * storage functionality is available in the host.
149 */
150 static int vmstor_proto_version;
151
152 #define STORVSC_LOGGING_NONE 0
153 #define STORVSC_LOGGING_ERROR 1
154 #define STORVSC_LOGGING_WARN 2
155
156 static int logging_level = STORVSC_LOGGING_ERROR;
157 module_param(logging_level, int, S_IRUGO|S_IWUSR);
158 MODULE_PARM_DESC(logging_level,
159 "Logging level, 0 - None, 1 - Error (default), 2 - Warning.");
160
do_logging(int level)161 static inline bool do_logging(int level)
162 {
163 return logging_level >= level;
164 }
165
166 #define storvsc_log(dev, level, fmt, ...) \
167 do { \
168 if (do_logging(level)) \
169 dev_warn(&(dev)->device, fmt, ##__VA_ARGS__); \
170 } while (0)
171
172 struct vmscsi_request {
173 u16 length;
174 u8 srb_status;
175 u8 scsi_status;
176
177 u8 port_number;
178 u8 path_id;
179 u8 target_id;
180 u8 lun;
181
182 u8 cdb_length;
183 u8 sense_info_length;
184 u8 data_in;
185 u8 reserved;
186
187 u32 data_transfer_length;
188
189 union {
190 u8 cdb[STORVSC_MAX_CMD_LEN];
191 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
192 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
193 };
194 /*
195 * The following was added in win8.
196 */
197 u16 reserve;
198 u8 queue_tag;
199 u8 queue_action;
200 u32 srb_flags;
201 u32 time_out_value;
202 u32 queue_sort_ey;
203
204 } __attribute((packed));
205
206 /*
207 * The list of windows version in order of preference.
208 */
209
210 static const int protocol_version[] = {
211 VMSTOR_PROTO_VERSION_WIN10,
212 VMSTOR_PROTO_VERSION_WIN8_1,
213 VMSTOR_PROTO_VERSION_WIN8,
214 };
215
216
217 /*
218 * This structure is sent during the initialization phase to get the different
219 * properties of the channel.
220 */
221
222 #define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL 0x1
223
224 struct vmstorage_channel_properties {
225 u32 reserved;
226 u16 max_channel_cnt;
227 u16 reserved1;
228
229 u32 flags;
230 u32 max_transfer_bytes;
231
232 u64 reserved2;
233 } __packed;
234
235 /* This structure is sent during the storage protocol negotiations. */
236 struct vmstorage_protocol_version {
237 /* Major (MSW) and minor (LSW) version numbers. */
238 u16 major_minor;
239
240 /*
241 * Revision number is auto-incremented whenever this file is changed
242 * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
243 * definitely indicate incompatibility--but it does indicate mismatched
244 * builds.
245 * This is only used on the windows side. Just set it to 0.
246 */
247 u16 revision;
248 } __packed;
249
250 /* Channel Property Flags */
251 #define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
252 #define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
253
254 struct vstor_packet {
255 /* Requested operation type */
256 enum vstor_packet_operation operation;
257
258 /* Flags - see below for values */
259 u32 flags;
260
261 /* Status of the request returned from the server side. */
262 u32 status;
263
264 /* Data payload area */
265 union {
266 /*
267 * Structure used to forward SCSI commands from the
268 * client to the server.
269 */
270 struct vmscsi_request vm_srb;
271
272 /* Structure used to query channel properties. */
273 struct vmstorage_channel_properties storage_channel_properties;
274
275 /* Used during version negotiations. */
276 struct vmstorage_protocol_version version;
277
278 /* Fibre channel address packet */
279 struct hv_fc_wwn_packet wwn_packet;
280
281 /* Number of sub-channels to create */
282 u16 sub_channel_count;
283
284 /* This will be the maximum of the union members */
285 u8 buffer[0x34];
286 };
287 } __packed;
288
289 /*
290 * Packet Flags:
291 *
292 * This flag indicates that the server should send back a completion for this
293 * packet.
294 */
295
296 #define REQUEST_COMPLETION_FLAG 0x1
297
298 /* Matches Windows-end */
299 enum storvsc_request_type {
300 WRITE_TYPE = 0,
301 READ_TYPE,
302 UNKNOWN_TYPE,
303 };
304
305 /*
306 * SRB status codes and masks. In the 8-bit field, the two high order bits
307 * are flags, while the remaining 6 bits are an integer status code. The
308 * definitions here include only the subset of the integer status codes that
309 * are tested for in this driver.
310 */
311 #define SRB_STATUS_AUTOSENSE_VALID 0x80
312 #define SRB_STATUS_QUEUE_FROZEN 0x40
313
314 /* SRB status integer codes */
315 #define SRB_STATUS_SUCCESS 0x01
316 #define SRB_STATUS_ABORTED 0x02
317 #define SRB_STATUS_ERROR 0x04
318 #define SRB_STATUS_INVALID_REQUEST 0x06
319 #define SRB_STATUS_TIMEOUT 0x09
320 #define SRB_STATUS_SELECTION_TIMEOUT 0x0A
321 #define SRB_STATUS_BUS_RESET 0x0E
322 #define SRB_STATUS_DATA_OVERRUN 0x12
323 #define SRB_STATUS_INVALID_LUN 0x20
324 #define SRB_STATUS_INTERNAL_ERROR 0x30
325
326 #define SRB_STATUS(status) \
327 (status & ~(SRB_STATUS_AUTOSENSE_VALID | SRB_STATUS_QUEUE_FROZEN))
328 /*
329 * This is the end of Protocol specific defines.
330 */
331
332 static int storvsc_ringbuffer_size = (128 * 1024);
333 static u32 max_outstanding_req_per_channel;
334 static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth);
335
336 static int storvsc_vcpus_per_sub_channel = 4;
337 static unsigned int storvsc_max_hw_queues;
338
339 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
340 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
341
342 module_param(storvsc_max_hw_queues, uint, 0644);
343 MODULE_PARM_DESC(storvsc_max_hw_queues, "Maximum number of hardware queues");
344
345 module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
346 MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
347
348 static int ring_avail_percent_lowater = 10;
349 module_param(ring_avail_percent_lowater, int, S_IRUGO);
350 MODULE_PARM_DESC(ring_avail_percent_lowater,
351 "Select a channel if available ring size > this in percent");
352
353 /*
354 * Timeout in seconds for all devices managed by this driver.
355 */
356 static int storvsc_timeout = 180;
357
358 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
359 static struct scsi_transport_template *fc_transport_template;
360 #endif
361
362 static struct scsi_host_template scsi_driver;
363 static void storvsc_on_channel_callback(void *context);
364
365 #define STORVSC_MAX_LUNS_PER_TARGET 255
366 #define STORVSC_MAX_TARGETS 2
367 #define STORVSC_MAX_CHANNELS 8
368
369 #define STORVSC_FC_MAX_LUNS_PER_TARGET 255
370 #define STORVSC_FC_MAX_TARGETS 128
371 #define STORVSC_FC_MAX_CHANNELS 8
372 #define STORVSC_FC_MAX_XFER_SIZE ((u32)(512 * 1024))
373
374 #define STORVSC_IDE_MAX_LUNS_PER_TARGET 64
375 #define STORVSC_IDE_MAX_TARGETS 1
376 #define STORVSC_IDE_MAX_CHANNELS 1
377
378 /*
379 * Upper bound on the size of a storvsc packet.
380 */
381 #define STORVSC_MAX_PKT_SIZE (sizeof(struct vmpacket_descriptor) +\
382 sizeof(struct vstor_packet))
383
384 struct storvsc_cmd_request {
385 struct scsi_cmnd *cmd;
386
387 struct hv_device *device;
388
389 /* Synchronize the request/response if needed */
390 struct completion wait_event;
391
392 struct vmbus_channel_packet_multipage_buffer mpb;
393 struct vmbus_packet_mpb_array *payload;
394 u32 payload_sz;
395
396 struct vstor_packet vstor_packet;
397 };
398
399
400 /* A storvsc device is a device object that contains a vmbus channel */
401 struct storvsc_device {
402 struct hv_device *device;
403
404 bool destroy;
405 bool drain_notify;
406 atomic_t num_outstanding_req;
407 struct Scsi_Host *host;
408
409 wait_queue_head_t waiting_to_drain;
410
411 /*
412 * Each unique Port/Path/Target represents 1 channel ie scsi
413 * controller. In reality, the pathid, targetid is always 0
414 * and the port is set by us
415 */
416 unsigned int port_number;
417 unsigned char path_id;
418 unsigned char target_id;
419
420 /*
421 * Max I/O, the device can support.
422 */
423 u32 max_transfer_bytes;
424 /*
425 * Number of sub-channels we will open.
426 */
427 u16 num_sc;
428 struct vmbus_channel **stor_chns;
429 /*
430 * Mask of CPUs bound to subchannels.
431 */
432 struct cpumask alloced_cpus;
433 /*
434 * Serializes modifications of stor_chns[] from storvsc_do_io()
435 * and storvsc_change_target_cpu().
436 */
437 spinlock_t lock;
438 /* Used for vsc/vsp channel reset process */
439 struct storvsc_cmd_request init_request;
440 struct storvsc_cmd_request reset_request;
441 /*
442 * Currently active port and node names for FC devices.
443 */
444 u64 node_name;
445 u64 port_name;
446 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
447 struct fc_rport *rport;
448 #endif
449 };
450
451 struct hv_host_device {
452 struct hv_device *dev;
453 unsigned int port;
454 unsigned char path;
455 unsigned char target;
456 struct workqueue_struct *handle_error_wq;
457 struct work_struct host_scan_work;
458 struct Scsi_Host *host;
459 };
460
461 struct storvsc_scan_work {
462 struct work_struct work;
463 struct Scsi_Host *host;
464 u8 lun;
465 u8 tgt_id;
466 };
467
storvsc_device_scan(struct work_struct * work)468 static void storvsc_device_scan(struct work_struct *work)
469 {
470 struct storvsc_scan_work *wrk;
471 struct scsi_device *sdev;
472
473 wrk = container_of(work, struct storvsc_scan_work, work);
474
475 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
476 if (!sdev)
477 goto done;
478 scsi_rescan_device(sdev);
479 scsi_device_put(sdev);
480
481 done:
482 kfree(wrk);
483 }
484
storvsc_host_scan(struct work_struct * work)485 static void storvsc_host_scan(struct work_struct *work)
486 {
487 struct Scsi_Host *host;
488 struct scsi_device *sdev;
489 struct hv_host_device *host_device =
490 container_of(work, struct hv_host_device, host_scan_work);
491
492 host = host_device->host;
493 /*
494 * Before scanning the host, first check to see if any of the
495 * currently known devices have been hot removed. We issue a
496 * "unit ready" command against all currently known devices.
497 * This I/O will result in an error for devices that have been
498 * removed. As part of handling the I/O error, we remove the device.
499 *
500 * When a LUN is added or removed, the host sends us a signal to
501 * scan the host. Thus we are forced to discover the LUNs that
502 * may have been removed this way.
503 */
504 mutex_lock(&host->scan_mutex);
505 shost_for_each_device(sdev, host)
506 scsi_test_unit_ready(sdev, 1, 1, NULL);
507 mutex_unlock(&host->scan_mutex);
508 /*
509 * Now scan the host to discover LUNs that may have been added.
510 */
511 scsi_scan_host(host);
512 }
513
storvsc_remove_lun(struct work_struct * work)514 static void storvsc_remove_lun(struct work_struct *work)
515 {
516 struct storvsc_scan_work *wrk;
517 struct scsi_device *sdev;
518
519 wrk = container_of(work, struct storvsc_scan_work, work);
520 if (!scsi_host_get(wrk->host))
521 goto done;
522
523 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
524
525 if (sdev) {
526 scsi_remove_device(sdev);
527 scsi_device_put(sdev);
528 }
529 scsi_host_put(wrk->host);
530
531 done:
532 kfree(wrk);
533 }
534
535
536 /*
537 * We can get incoming messages from the host that are not in response to
538 * messages that we have sent out. An example of this would be messages
539 * received by the guest to notify dynamic addition/removal of LUNs. To
540 * deal with potential race conditions where the driver may be in the
541 * midst of being unloaded when we might receive an unsolicited message
542 * from the host, we have implemented a mechanism to gurantee sequential
543 * consistency:
544 *
545 * 1) Once the device is marked as being destroyed, we will fail all
546 * outgoing messages.
547 * 2) We permit incoming messages when the device is being destroyed,
548 * only to properly account for messages already sent out.
549 */
550
get_out_stor_device(struct hv_device * device)551 static inline struct storvsc_device *get_out_stor_device(
552 struct hv_device *device)
553 {
554 struct storvsc_device *stor_device;
555
556 stor_device = hv_get_drvdata(device);
557
558 if (stor_device && stor_device->destroy)
559 stor_device = NULL;
560
561 return stor_device;
562 }
563
564
storvsc_wait_to_drain(struct storvsc_device * dev)565 static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
566 {
567 dev->drain_notify = true;
568 wait_event(dev->waiting_to_drain,
569 atomic_read(&dev->num_outstanding_req) == 0);
570 dev->drain_notify = false;
571 }
572
get_in_stor_device(struct hv_device * device)573 static inline struct storvsc_device *get_in_stor_device(
574 struct hv_device *device)
575 {
576 struct storvsc_device *stor_device;
577
578 stor_device = hv_get_drvdata(device);
579
580 if (!stor_device)
581 goto get_in_err;
582
583 /*
584 * If the device is being destroyed; allow incoming
585 * traffic only to cleanup outstanding requests.
586 */
587
588 if (stor_device->destroy &&
589 (atomic_read(&stor_device->num_outstanding_req) == 0))
590 stor_device = NULL;
591
592 get_in_err:
593 return stor_device;
594
595 }
596
storvsc_change_target_cpu(struct vmbus_channel * channel,u32 old,u32 new)597 static void storvsc_change_target_cpu(struct vmbus_channel *channel, u32 old,
598 u32 new)
599 {
600 struct storvsc_device *stor_device;
601 struct vmbus_channel *cur_chn;
602 bool old_is_alloced = false;
603 struct hv_device *device;
604 unsigned long flags;
605 int cpu;
606
607 device = channel->primary_channel ?
608 channel->primary_channel->device_obj
609 : channel->device_obj;
610 stor_device = get_out_stor_device(device);
611 if (!stor_device)
612 return;
613
614 /* See storvsc_do_io() -> get_og_chn(). */
615 spin_lock_irqsave(&stor_device->lock, flags);
616
617 /*
618 * Determines if the storvsc device has other channels assigned to
619 * the "old" CPU to update the alloced_cpus mask and the stor_chns
620 * array.
621 */
622 if (device->channel != channel && device->channel->target_cpu == old) {
623 cur_chn = device->channel;
624 old_is_alloced = true;
625 goto old_is_alloced;
626 }
627 list_for_each_entry(cur_chn, &device->channel->sc_list, sc_list) {
628 if (cur_chn == channel)
629 continue;
630 if (cur_chn->target_cpu == old) {
631 old_is_alloced = true;
632 goto old_is_alloced;
633 }
634 }
635
636 old_is_alloced:
637 if (old_is_alloced)
638 WRITE_ONCE(stor_device->stor_chns[old], cur_chn);
639 else
640 cpumask_clear_cpu(old, &stor_device->alloced_cpus);
641
642 /* "Flush" the stor_chns array. */
643 for_each_possible_cpu(cpu) {
644 if (stor_device->stor_chns[cpu] && !cpumask_test_cpu(
645 cpu, &stor_device->alloced_cpus))
646 WRITE_ONCE(stor_device->stor_chns[cpu], NULL);
647 }
648
649 WRITE_ONCE(stor_device->stor_chns[new], channel);
650 cpumask_set_cpu(new, &stor_device->alloced_cpus);
651
652 spin_unlock_irqrestore(&stor_device->lock, flags);
653 }
654
storvsc_next_request_id(struct vmbus_channel * channel,u64 rqst_addr)655 static u64 storvsc_next_request_id(struct vmbus_channel *channel, u64 rqst_addr)
656 {
657 struct storvsc_cmd_request *request =
658 (struct storvsc_cmd_request *)(unsigned long)rqst_addr;
659
660 if (rqst_addr == VMBUS_RQST_INIT)
661 return VMBUS_RQST_INIT;
662 if (rqst_addr == VMBUS_RQST_RESET)
663 return VMBUS_RQST_RESET;
664
665 /*
666 * Cannot return an ID of 0, which is reserved for an unsolicited
667 * message from Hyper-V.
668 */
669 return (u64)blk_mq_unique_tag(scsi_cmd_to_rq(request->cmd)) + 1;
670 }
671
handle_sc_creation(struct vmbus_channel * new_sc)672 static void handle_sc_creation(struct vmbus_channel *new_sc)
673 {
674 struct hv_device *device = new_sc->primary_channel->device_obj;
675 struct device *dev = &device->device;
676 struct storvsc_device *stor_device;
677 struct vmstorage_channel_properties props;
678 int ret;
679
680 stor_device = get_out_stor_device(device);
681 if (!stor_device)
682 return;
683
684 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
685 new_sc->max_pkt_size = STORVSC_MAX_PKT_SIZE;
686
687 new_sc->next_request_id_callback = storvsc_next_request_id;
688
689 ret = vmbus_open(new_sc,
690 storvsc_ringbuffer_size,
691 storvsc_ringbuffer_size,
692 (void *)&props,
693 sizeof(struct vmstorage_channel_properties),
694 storvsc_on_channel_callback, new_sc);
695
696 /* In case vmbus_open() fails, we don't use the sub-channel. */
697 if (ret != 0) {
698 dev_err(dev, "Failed to open sub-channel: err=%d\n", ret);
699 return;
700 }
701
702 new_sc->change_target_cpu_callback = storvsc_change_target_cpu;
703
704 /* Add the sub-channel to the array of available channels. */
705 stor_device->stor_chns[new_sc->target_cpu] = new_sc;
706 cpumask_set_cpu(new_sc->target_cpu, &stor_device->alloced_cpus);
707 }
708
handle_multichannel_storage(struct hv_device * device,int max_chns)709 static void handle_multichannel_storage(struct hv_device *device, int max_chns)
710 {
711 struct device *dev = &device->device;
712 struct storvsc_device *stor_device;
713 int num_sc;
714 struct storvsc_cmd_request *request;
715 struct vstor_packet *vstor_packet;
716 int ret, t;
717
718 /*
719 * If the number of CPUs is artificially restricted, such as
720 * with maxcpus=1 on the kernel boot line, Hyper-V could offer
721 * sub-channels >= the number of CPUs. These sub-channels
722 * should not be created. The primary channel is already created
723 * and assigned to one CPU, so check against # CPUs - 1.
724 */
725 num_sc = min((int)(num_online_cpus() - 1), max_chns);
726 if (!num_sc)
727 return;
728
729 stor_device = get_out_stor_device(device);
730 if (!stor_device)
731 return;
732
733 stor_device->num_sc = num_sc;
734 request = &stor_device->init_request;
735 vstor_packet = &request->vstor_packet;
736
737 /*
738 * Establish a handler for dealing with subchannels.
739 */
740 vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
741
742 /*
743 * Request the host to create sub-channels.
744 */
745 memset(request, 0, sizeof(struct storvsc_cmd_request));
746 init_completion(&request->wait_event);
747 vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
748 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
749 vstor_packet->sub_channel_count = num_sc;
750
751 ret = vmbus_sendpacket(device->channel, vstor_packet,
752 sizeof(struct vstor_packet),
753 VMBUS_RQST_INIT,
754 VM_PKT_DATA_INBAND,
755 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
756
757 if (ret != 0) {
758 dev_err(dev, "Failed to create sub-channel: err=%d\n", ret);
759 return;
760 }
761
762 t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
763 if (t == 0) {
764 dev_err(dev, "Failed to create sub-channel: timed out\n");
765 return;
766 }
767
768 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
769 vstor_packet->status != 0) {
770 dev_err(dev, "Failed to create sub-channel: op=%d, sts=%d\n",
771 vstor_packet->operation, vstor_packet->status);
772 return;
773 }
774
775 /*
776 * We need to do nothing here, because vmbus_process_offer()
777 * invokes channel->sc_creation_callback, which will open and use
778 * the sub-channel(s).
779 */
780 }
781
cache_wwn(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet)782 static void cache_wwn(struct storvsc_device *stor_device,
783 struct vstor_packet *vstor_packet)
784 {
785 /*
786 * Cache the currently active port and node ww names.
787 */
788 if (vstor_packet->wwn_packet.primary_active) {
789 stor_device->node_name =
790 wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
791 stor_device->port_name =
792 wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
793 } else {
794 stor_device->node_name =
795 wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
796 stor_device->port_name =
797 wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
798 }
799 }
800
801
storvsc_execute_vstor_op(struct hv_device * device,struct storvsc_cmd_request * request,bool status_check)802 static int storvsc_execute_vstor_op(struct hv_device *device,
803 struct storvsc_cmd_request *request,
804 bool status_check)
805 {
806 struct storvsc_device *stor_device;
807 struct vstor_packet *vstor_packet;
808 int ret, t;
809
810 stor_device = get_out_stor_device(device);
811 if (!stor_device)
812 return -ENODEV;
813
814 vstor_packet = &request->vstor_packet;
815
816 init_completion(&request->wait_event);
817 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
818
819 ret = vmbus_sendpacket(device->channel, vstor_packet,
820 sizeof(struct vstor_packet),
821 VMBUS_RQST_INIT,
822 VM_PKT_DATA_INBAND,
823 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
824 if (ret != 0)
825 return ret;
826
827 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
828 if (t == 0)
829 return -ETIMEDOUT;
830
831 if (!status_check)
832 return ret;
833
834 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
835 vstor_packet->status != 0)
836 return -EINVAL;
837
838 return ret;
839 }
840
storvsc_channel_init(struct hv_device * device,bool is_fc)841 static int storvsc_channel_init(struct hv_device *device, bool is_fc)
842 {
843 struct storvsc_device *stor_device;
844 struct storvsc_cmd_request *request;
845 struct vstor_packet *vstor_packet;
846 int ret, i;
847 int max_chns;
848 bool process_sub_channels = false;
849
850 stor_device = get_out_stor_device(device);
851 if (!stor_device)
852 return -ENODEV;
853
854 request = &stor_device->init_request;
855 vstor_packet = &request->vstor_packet;
856
857 /*
858 * Now, initiate the vsc/vsp initialization protocol on the open
859 * channel
860 */
861 memset(request, 0, sizeof(struct storvsc_cmd_request));
862 vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
863 ret = storvsc_execute_vstor_op(device, request, true);
864 if (ret)
865 return ret;
866 /*
867 * Query host supported protocol version.
868 */
869
870 for (i = 0; i < ARRAY_SIZE(protocol_version); i++) {
871 /* reuse the packet for version range supported */
872 memset(vstor_packet, 0, sizeof(struct vstor_packet));
873 vstor_packet->operation =
874 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
875
876 vstor_packet->version.major_minor = protocol_version[i];
877
878 /*
879 * The revision number is only used in Windows; set it to 0.
880 */
881 vstor_packet->version.revision = 0;
882 ret = storvsc_execute_vstor_op(device, request, false);
883 if (ret != 0)
884 return ret;
885
886 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
887 return -EINVAL;
888
889 if (vstor_packet->status == 0) {
890 vmstor_proto_version = protocol_version[i];
891
892 break;
893 }
894 }
895
896 if (vstor_packet->status != 0) {
897 dev_err(&device->device, "Obsolete Hyper-V version\n");
898 return -EINVAL;
899 }
900
901
902 memset(vstor_packet, 0, sizeof(struct vstor_packet));
903 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
904 ret = storvsc_execute_vstor_op(device, request, true);
905 if (ret != 0)
906 return ret;
907
908 /*
909 * Check to see if multi-channel support is there.
910 * Hosts that implement protocol version of 5.1 and above
911 * support multi-channel.
912 */
913 max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
914
915 /*
916 * Allocate state to manage the sub-channels.
917 * We allocate an array based on the numbers of possible CPUs
918 * (Hyper-V does not support cpu online/offline).
919 * This Array will be sparseley populated with unique
920 * channels - primary + sub-channels.
921 * We will however populate all the slots to evenly distribute
922 * the load.
923 */
924 stor_device->stor_chns = kcalloc(num_possible_cpus(), sizeof(void *),
925 GFP_KERNEL);
926 if (stor_device->stor_chns == NULL)
927 return -ENOMEM;
928
929 device->channel->change_target_cpu_callback = storvsc_change_target_cpu;
930
931 stor_device->stor_chns[device->channel->target_cpu] = device->channel;
932 cpumask_set_cpu(device->channel->target_cpu,
933 &stor_device->alloced_cpus);
934
935 if (vstor_packet->storage_channel_properties.flags &
936 STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
937 process_sub_channels = true;
938
939 stor_device->max_transfer_bytes =
940 vstor_packet->storage_channel_properties.max_transfer_bytes;
941
942 if (!is_fc)
943 goto done;
944
945 /*
946 * For FC devices retrieve FC HBA data.
947 */
948 memset(vstor_packet, 0, sizeof(struct vstor_packet));
949 vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
950 ret = storvsc_execute_vstor_op(device, request, true);
951 if (ret != 0)
952 return ret;
953
954 /*
955 * Cache the currently active port and node ww names.
956 */
957 cache_wwn(stor_device, vstor_packet);
958
959 done:
960
961 memset(vstor_packet, 0, sizeof(struct vstor_packet));
962 vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
963 ret = storvsc_execute_vstor_op(device, request, true);
964 if (ret != 0)
965 return ret;
966
967 if (process_sub_channels)
968 handle_multichannel_storage(device, max_chns);
969
970 return ret;
971 }
972
storvsc_handle_error(struct vmscsi_request * vm_srb,struct scsi_cmnd * scmnd,struct Scsi_Host * host,u8 asc,u8 ascq)973 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
974 struct scsi_cmnd *scmnd,
975 struct Scsi_Host *host,
976 u8 asc, u8 ascq)
977 {
978 struct storvsc_scan_work *wrk;
979 void (*process_err_fn)(struct work_struct *work);
980 struct hv_host_device *host_dev = shost_priv(host);
981
982 switch (SRB_STATUS(vm_srb->srb_status)) {
983 case SRB_STATUS_ERROR:
984 case SRB_STATUS_ABORTED:
985 case SRB_STATUS_INVALID_REQUEST:
986 case SRB_STATUS_INTERNAL_ERROR:
987 case SRB_STATUS_TIMEOUT:
988 case SRB_STATUS_SELECTION_TIMEOUT:
989 case SRB_STATUS_BUS_RESET:
990 case SRB_STATUS_DATA_OVERRUN:
991 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID) {
992 /* Check for capacity change */
993 if ((asc == 0x2a) && (ascq == 0x9)) {
994 process_err_fn = storvsc_device_scan;
995 /* Retry the I/O that triggered this. */
996 set_host_byte(scmnd, DID_REQUEUE);
997 goto do_work;
998 }
999
1000 /*
1001 * Check for "Operating parameters have changed"
1002 * due to Hyper-V changing the VHD/VHDX BlockSize
1003 * when adding/removing a differencing disk. This
1004 * causes discard_granularity to change, so do a
1005 * rescan to pick up the new granularity. We don't
1006 * want scsi_report_sense() to output a message
1007 * that a sysadmin wouldn't know what to do with.
1008 */
1009 if ((asc == 0x3f) && (ascq != 0x03) &&
1010 (ascq != 0x0e)) {
1011 process_err_fn = storvsc_device_scan;
1012 set_host_byte(scmnd, DID_REQUEUE);
1013 goto do_work;
1014 }
1015
1016 /*
1017 * Otherwise, let upper layer deal with the
1018 * error when sense message is present
1019 */
1020 return;
1021 }
1022
1023 /*
1024 * If there is an error; offline the device since all
1025 * error recovery strategies would have already been
1026 * deployed on the host side. However, if the command
1027 * were a pass-through command deal with it appropriately.
1028 */
1029 switch (scmnd->cmnd[0]) {
1030 case ATA_16:
1031 case ATA_12:
1032 set_host_byte(scmnd, DID_PASSTHROUGH);
1033 break;
1034 /*
1035 * On some Hyper-V hosts TEST_UNIT_READY command can
1036 * return SRB_STATUS_ERROR. Let the upper level code
1037 * deal with it based on the sense information.
1038 */
1039 case TEST_UNIT_READY:
1040 break;
1041 default:
1042 set_host_byte(scmnd, DID_ERROR);
1043 }
1044 return;
1045
1046 case SRB_STATUS_INVALID_LUN:
1047 set_host_byte(scmnd, DID_NO_CONNECT);
1048 process_err_fn = storvsc_remove_lun;
1049 goto do_work;
1050
1051 }
1052 return;
1053
1054 do_work:
1055 /*
1056 * We need to schedule work to process this error; schedule it.
1057 */
1058 wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1059 if (!wrk) {
1060 set_host_byte(scmnd, DID_BAD_TARGET);
1061 return;
1062 }
1063
1064 wrk->host = host;
1065 wrk->lun = vm_srb->lun;
1066 wrk->tgt_id = vm_srb->target_id;
1067 INIT_WORK(&wrk->work, process_err_fn);
1068 queue_work(host_dev->handle_error_wq, &wrk->work);
1069 }
1070
1071
storvsc_command_completion(struct storvsc_cmd_request * cmd_request,struct storvsc_device * stor_dev)1072 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
1073 struct storvsc_device *stor_dev)
1074 {
1075 struct scsi_cmnd *scmnd = cmd_request->cmd;
1076 struct scsi_sense_hdr sense_hdr;
1077 struct vmscsi_request *vm_srb;
1078 u32 data_transfer_length;
1079 struct Scsi_Host *host;
1080 u32 payload_sz = cmd_request->payload_sz;
1081 void *payload = cmd_request->payload;
1082 bool sense_ok;
1083
1084 host = stor_dev->host;
1085
1086 vm_srb = &cmd_request->vstor_packet.vm_srb;
1087 data_transfer_length = vm_srb->data_transfer_length;
1088
1089 scmnd->result = vm_srb->scsi_status;
1090
1091 if (scmnd->result) {
1092 sense_ok = scsi_normalize_sense(scmnd->sense_buffer,
1093 SCSI_SENSE_BUFFERSIZE, &sense_hdr);
1094
1095 if (sense_ok && do_logging(STORVSC_LOGGING_WARN))
1096 scsi_print_sense_hdr(scmnd->device, "storvsc",
1097 &sense_hdr);
1098 }
1099
1100 if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
1101 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
1102 sense_hdr.ascq);
1103 /*
1104 * The Windows driver set data_transfer_length on
1105 * SRB_STATUS_DATA_OVERRUN. On other errors, this value
1106 * is untouched. In these cases we set it to 0.
1107 */
1108 if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
1109 data_transfer_length = 0;
1110 }
1111
1112 /* Validate data_transfer_length (from Hyper-V) */
1113 if (data_transfer_length > cmd_request->payload->range.len)
1114 data_transfer_length = cmd_request->payload->range.len;
1115
1116 scsi_set_resid(scmnd,
1117 cmd_request->payload->range.len - data_transfer_length);
1118
1119 scsi_done(scmnd);
1120
1121 if (payload_sz >
1122 sizeof(struct vmbus_channel_packet_multipage_buffer))
1123 kfree(payload);
1124 }
1125
storvsc_on_io_completion(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet,struct storvsc_cmd_request * request)1126 static void storvsc_on_io_completion(struct storvsc_device *stor_device,
1127 struct vstor_packet *vstor_packet,
1128 struct storvsc_cmd_request *request)
1129 {
1130 struct vstor_packet *stor_pkt;
1131 struct hv_device *device = stor_device->device;
1132
1133 stor_pkt = &request->vstor_packet;
1134
1135 /*
1136 * The current SCSI handling on the host side does
1137 * not correctly handle:
1138 * INQUIRY command with page code parameter set to 0x80
1139 * MODE_SENSE command with cmd[2] == 0x1c
1140 *
1141 * Setup srb and scsi status so this won't be fatal.
1142 * We do this so we can distinguish truly fatal failues
1143 * (srb status == 0x4) and off-line the device in that case.
1144 */
1145
1146 if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1147 (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1148 vstor_packet->vm_srb.scsi_status = 0;
1149 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1150 }
1151
1152 /* Copy over the status...etc */
1153 stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1154 stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1155
1156 /*
1157 * Copy over the sense_info_length, but limit to the known max
1158 * size if Hyper-V returns a bad value.
1159 */
1160 stor_pkt->vm_srb.sense_info_length = min_t(u8, STORVSC_SENSE_BUFFER_SIZE,
1161 vstor_packet->vm_srb.sense_info_length);
1162
1163 if (vstor_packet->vm_srb.scsi_status != 0 ||
1164 vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS) {
1165
1166 /*
1167 * Log TEST_UNIT_READY errors only as warnings. Hyper-V can
1168 * return errors when detecting devices using TEST_UNIT_READY,
1169 * and logging these as errors produces unhelpful noise.
1170 */
1171 int loglevel = (stor_pkt->vm_srb.cdb[0] == TEST_UNIT_READY) ?
1172 STORVSC_LOGGING_WARN : STORVSC_LOGGING_ERROR;
1173
1174 storvsc_log(device, loglevel,
1175 "tag#%d cmd 0x%x status: scsi 0x%x srb 0x%x hv 0x%x\n",
1176 scsi_cmd_to_rq(request->cmd)->tag,
1177 stor_pkt->vm_srb.cdb[0],
1178 vstor_packet->vm_srb.scsi_status,
1179 vstor_packet->vm_srb.srb_status,
1180 vstor_packet->status);
1181 }
1182
1183 if (vstor_packet->vm_srb.scsi_status == SAM_STAT_CHECK_CONDITION &&
1184 (vstor_packet->vm_srb.srb_status & SRB_STATUS_AUTOSENSE_VALID))
1185 memcpy(request->cmd->sense_buffer,
1186 vstor_packet->vm_srb.sense_data,
1187 stor_pkt->vm_srb.sense_info_length);
1188
1189 stor_pkt->vm_srb.data_transfer_length =
1190 vstor_packet->vm_srb.data_transfer_length;
1191
1192 storvsc_command_completion(request, stor_device);
1193
1194 if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1195 stor_device->drain_notify)
1196 wake_up(&stor_device->waiting_to_drain);
1197 }
1198
storvsc_on_receive(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet,struct storvsc_cmd_request * request)1199 static void storvsc_on_receive(struct storvsc_device *stor_device,
1200 struct vstor_packet *vstor_packet,
1201 struct storvsc_cmd_request *request)
1202 {
1203 struct hv_host_device *host_dev;
1204 switch (vstor_packet->operation) {
1205 case VSTOR_OPERATION_COMPLETE_IO:
1206 storvsc_on_io_completion(stor_device, vstor_packet, request);
1207 break;
1208
1209 case VSTOR_OPERATION_REMOVE_DEVICE:
1210 case VSTOR_OPERATION_ENUMERATE_BUS:
1211 host_dev = shost_priv(stor_device->host);
1212 queue_work(
1213 host_dev->handle_error_wq, &host_dev->host_scan_work);
1214 break;
1215
1216 case VSTOR_OPERATION_FCHBA_DATA:
1217 cache_wwn(stor_device, vstor_packet);
1218 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1219 fc_host_node_name(stor_device->host) = stor_device->node_name;
1220 fc_host_port_name(stor_device->host) = stor_device->port_name;
1221 #endif
1222 break;
1223 default:
1224 break;
1225 }
1226 }
1227
storvsc_on_channel_callback(void * context)1228 static void storvsc_on_channel_callback(void *context)
1229 {
1230 struct vmbus_channel *channel = (struct vmbus_channel *)context;
1231 const struct vmpacket_descriptor *desc;
1232 struct hv_device *device;
1233 struct storvsc_device *stor_device;
1234 struct Scsi_Host *shost;
1235 unsigned long time_limit = jiffies + msecs_to_jiffies(CALLBACK_TIMEOUT);
1236
1237 if (channel->primary_channel != NULL)
1238 device = channel->primary_channel->device_obj;
1239 else
1240 device = channel->device_obj;
1241
1242 stor_device = get_in_stor_device(device);
1243 if (!stor_device)
1244 return;
1245
1246 shost = stor_device->host;
1247
1248 foreach_vmbus_pkt(desc, channel) {
1249 struct vstor_packet *packet = hv_pkt_data(desc);
1250 struct storvsc_cmd_request *request = NULL;
1251 u32 pktlen = hv_pkt_datalen(desc);
1252 u64 rqst_id = desc->trans_id;
1253 u32 minlen = rqst_id ? sizeof(struct vstor_packet) :
1254 sizeof(enum vstor_packet_operation);
1255
1256 if (unlikely(time_after(jiffies, time_limit))) {
1257 hv_pkt_iter_close(channel);
1258 return;
1259 }
1260
1261 if (pktlen < minlen) {
1262 dev_err(&device->device,
1263 "Invalid pkt: id=%llu, len=%u, minlen=%u\n",
1264 rqst_id, pktlen, minlen);
1265 continue;
1266 }
1267
1268 if (rqst_id == VMBUS_RQST_INIT) {
1269 request = &stor_device->init_request;
1270 } else if (rqst_id == VMBUS_RQST_RESET) {
1271 request = &stor_device->reset_request;
1272 } else {
1273 /* Hyper-V can send an unsolicited message with ID of 0 */
1274 if (rqst_id == 0) {
1275 /*
1276 * storvsc_on_receive() looks at the vstor_packet in the message
1277 * from the ring buffer.
1278 *
1279 * - If the operation in the vstor_packet is COMPLETE_IO, then
1280 * we call storvsc_on_io_completion(), and dereference the
1281 * guest memory address. Make sure we don't call
1282 * storvsc_on_io_completion() with a guest memory address
1283 * that is zero if Hyper-V were to construct and send such
1284 * a bogus packet.
1285 *
1286 * - If the operation in the vstor_packet is FCHBA_DATA, then
1287 * we call cache_wwn(), and access the data payload area of
1288 * the packet (wwn_packet); however, there is no guarantee
1289 * that the packet is big enough to contain such area.
1290 * Future-proof the code by rejecting such a bogus packet.
1291 */
1292 if (packet->operation == VSTOR_OPERATION_COMPLETE_IO ||
1293 packet->operation == VSTOR_OPERATION_FCHBA_DATA) {
1294 dev_err(&device->device, "Invalid packet with ID of 0\n");
1295 continue;
1296 }
1297 } else {
1298 struct scsi_cmnd *scmnd;
1299
1300 /* Transaction 'rqst_id' corresponds to tag 'rqst_id - 1' */
1301 scmnd = scsi_host_find_tag(shost, rqst_id - 1);
1302 if (scmnd == NULL) {
1303 dev_err(&device->device, "Incorrect transaction ID\n");
1304 continue;
1305 }
1306 request = (struct storvsc_cmd_request *)scsi_cmd_priv(scmnd);
1307 scsi_dma_unmap(scmnd);
1308 }
1309
1310 storvsc_on_receive(stor_device, packet, request);
1311 continue;
1312 }
1313
1314 memcpy(&request->vstor_packet, packet,
1315 sizeof(struct vstor_packet));
1316 complete(&request->wait_event);
1317 }
1318 }
1319
storvsc_connect_to_vsp(struct hv_device * device,u32 ring_size,bool is_fc)1320 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
1321 bool is_fc)
1322 {
1323 struct vmstorage_channel_properties props;
1324 int ret;
1325
1326 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1327
1328 device->channel->max_pkt_size = STORVSC_MAX_PKT_SIZE;
1329 device->channel->next_request_id_callback = storvsc_next_request_id;
1330
1331 ret = vmbus_open(device->channel,
1332 ring_size,
1333 ring_size,
1334 (void *)&props,
1335 sizeof(struct vmstorage_channel_properties),
1336 storvsc_on_channel_callback, device->channel);
1337
1338 if (ret != 0)
1339 return ret;
1340
1341 ret = storvsc_channel_init(device, is_fc);
1342
1343 return ret;
1344 }
1345
storvsc_dev_remove(struct hv_device * device)1346 static int storvsc_dev_remove(struct hv_device *device)
1347 {
1348 struct storvsc_device *stor_device;
1349
1350 stor_device = hv_get_drvdata(device);
1351
1352 stor_device->destroy = true;
1353
1354 /* Make sure flag is set before waiting */
1355 wmb();
1356
1357 /*
1358 * At this point, all outbound traffic should be disable. We
1359 * only allow inbound traffic (responses) to proceed so that
1360 * outstanding requests can be completed.
1361 */
1362
1363 storvsc_wait_to_drain(stor_device);
1364
1365 /*
1366 * Since we have already drained, we don't need to busy wait
1367 * as was done in final_release_stor_device()
1368 * Note that we cannot set the ext pointer to NULL until
1369 * we have drained - to drain the outgoing packets, we need to
1370 * allow incoming packets.
1371 */
1372 hv_set_drvdata(device, NULL);
1373
1374 /* Close the channel */
1375 vmbus_close(device->channel);
1376
1377 kfree(stor_device->stor_chns);
1378 kfree(stor_device);
1379 return 0;
1380 }
1381
get_og_chn(struct storvsc_device * stor_device,u16 q_num)1382 static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device,
1383 u16 q_num)
1384 {
1385 u16 slot = 0;
1386 u16 hash_qnum;
1387 const struct cpumask *node_mask;
1388 int num_channels, tgt_cpu;
1389
1390 if (stor_device->num_sc == 0) {
1391 stor_device->stor_chns[q_num] = stor_device->device->channel;
1392 return stor_device->device->channel;
1393 }
1394
1395 /*
1396 * Our channel array is sparsley populated and we
1397 * initiated I/O on a processor/hw-q that does not
1398 * currently have a designated channel. Fix this.
1399 * The strategy is simple:
1400 * I. Ensure NUMA locality
1401 * II. Distribute evenly (best effort)
1402 */
1403
1404 node_mask = cpumask_of_node(cpu_to_node(q_num));
1405
1406 num_channels = 0;
1407 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1408 if (cpumask_test_cpu(tgt_cpu, node_mask))
1409 num_channels++;
1410 }
1411 if (num_channels == 0) {
1412 stor_device->stor_chns[q_num] = stor_device->device->channel;
1413 return stor_device->device->channel;
1414 }
1415
1416 hash_qnum = q_num;
1417 while (hash_qnum >= num_channels)
1418 hash_qnum -= num_channels;
1419
1420 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1421 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1422 continue;
1423 if (slot == hash_qnum)
1424 break;
1425 slot++;
1426 }
1427
1428 stor_device->stor_chns[q_num] = stor_device->stor_chns[tgt_cpu];
1429
1430 return stor_device->stor_chns[q_num];
1431 }
1432
1433
storvsc_do_io(struct hv_device * device,struct storvsc_cmd_request * request,u16 q_num)1434 static int storvsc_do_io(struct hv_device *device,
1435 struct storvsc_cmd_request *request, u16 q_num)
1436 {
1437 struct storvsc_device *stor_device;
1438 struct vstor_packet *vstor_packet;
1439 struct vmbus_channel *outgoing_channel, *channel;
1440 unsigned long flags;
1441 int ret = 0;
1442 const struct cpumask *node_mask;
1443 int tgt_cpu;
1444
1445 vstor_packet = &request->vstor_packet;
1446 stor_device = get_out_stor_device(device);
1447
1448 if (!stor_device)
1449 return -ENODEV;
1450
1451
1452 request->device = device;
1453 /*
1454 * Select an appropriate channel to send the request out.
1455 */
1456 /* See storvsc_change_target_cpu(). */
1457 outgoing_channel = READ_ONCE(stor_device->stor_chns[q_num]);
1458 if (outgoing_channel != NULL) {
1459 if (outgoing_channel->target_cpu == q_num) {
1460 /*
1461 * Ideally, we want to pick a different channel if
1462 * available on the same NUMA node.
1463 */
1464 node_mask = cpumask_of_node(cpu_to_node(q_num));
1465 for_each_cpu_wrap(tgt_cpu,
1466 &stor_device->alloced_cpus, q_num + 1) {
1467 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1468 continue;
1469 if (tgt_cpu == q_num)
1470 continue;
1471 channel = READ_ONCE(
1472 stor_device->stor_chns[tgt_cpu]);
1473 if (channel == NULL)
1474 continue;
1475 if (hv_get_avail_to_write_percent(
1476 &channel->outbound)
1477 > ring_avail_percent_lowater) {
1478 outgoing_channel = channel;
1479 goto found_channel;
1480 }
1481 }
1482
1483 /*
1484 * All the other channels on the same NUMA node are
1485 * busy. Try to use the channel on the current CPU
1486 */
1487 if (hv_get_avail_to_write_percent(
1488 &outgoing_channel->outbound)
1489 > ring_avail_percent_lowater)
1490 goto found_channel;
1491
1492 /*
1493 * If we reach here, all the channels on the current
1494 * NUMA node are busy. Try to find a channel in
1495 * other NUMA nodes
1496 */
1497 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1498 if (cpumask_test_cpu(tgt_cpu, node_mask))
1499 continue;
1500 channel = READ_ONCE(
1501 stor_device->stor_chns[tgt_cpu]);
1502 if (channel == NULL)
1503 continue;
1504 if (hv_get_avail_to_write_percent(
1505 &channel->outbound)
1506 > ring_avail_percent_lowater) {
1507 outgoing_channel = channel;
1508 goto found_channel;
1509 }
1510 }
1511 }
1512 } else {
1513 spin_lock_irqsave(&stor_device->lock, flags);
1514 outgoing_channel = stor_device->stor_chns[q_num];
1515 if (outgoing_channel != NULL) {
1516 spin_unlock_irqrestore(&stor_device->lock, flags);
1517 goto found_channel;
1518 }
1519 outgoing_channel = get_og_chn(stor_device, q_num);
1520 spin_unlock_irqrestore(&stor_device->lock, flags);
1521 }
1522
1523 found_channel:
1524 vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1525
1526 vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
1527
1528
1529 vstor_packet->vm_srb.sense_info_length = STORVSC_SENSE_BUFFER_SIZE;
1530
1531
1532 vstor_packet->vm_srb.data_transfer_length =
1533 request->payload->range.len;
1534
1535 vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1536
1537 if (request->payload->range.len) {
1538
1539 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1540 request->payload, request->payload_sz,
1541 vstor_packet,
1542 sizeof(struct vstor_packet),
1543 (unsigned long)request);
1544 } else {
1545 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1546 sizeof(struct vstor_packet),
1547 (unsigned long)request,
1548 VM_PKT_DATA_INBAND,
1549 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1550 }
1551
1552 if (ret != 0)
1553 return ret;
1554
1555 atomic_inc(&stor_device->num_outstanding_req);
1556
1557 return ret;
1558 }
1559
storvsc_device_alloc(struct scsi_device * sdevice)1560 static int storvsc_device_alloc(struct scsi_device *sdevice)
1561 {
1562 /*
1563 * Set blist flag to permit the reading of the VPD pages even when
1564 * the target may claim SPC-2 compliance. MSFT targets currently
1565 * claim SPC-2 compliance while they implement post SPC-2 features.
1566 * With this flag we can correctly handle WRITE_SAME_16 issues.
1567 *
1568 * Hypervisor reports SCSI_UNKNOWN type for DVD ROM device but
1569 * still supports REPORT LUN.
1570 */
1571 sdevice->sdev_bflags = BLIST_REPORTLUN2 | BLIST_TRY_VPD_PAGES;
1572
1573 return 0;
1574 }
1575
storvsc_device_configure(struct scsi_device * sdevice)1576 static int storvsc_device_configure(struct scsi_device *sdevice)
1577 {
1578 blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1579
1580 /* storvsc devices don't support MAINTENANCE_IN SCSI cmd */
1581 sdevice->no_report_opcodes = 1;
1582 sdevice->no_write_same = 1;
1583
1584 /*
1585 * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1586 * if the device is a MSFT virtual device. If the host is
1587 * WIN10 or newer, allow write_same.
1588 */
1589 if (!strncmp(sdevice->vendor, "Msft", 4)) {
1590 switch (vmstor_proto_version) {
1591 case VMSTOR_PROTO_VERSION_WIN8:
1592 case VMSTOR_PROTO_VERSION_WIN8_1:
1593 sdevice->scsi_level = SCSI_SPC_3;
1594 break;
1595 }
1596
1597 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1598 sdevice->no_write_same = 0;
1599 }
1600
1601 return 0;
1602 }
1603
storvsc_get_chs(struct scsi_device * sdev,struct block_device * bdev,sector_t capacity,int * info)1604 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1605 sector_t capacity, int *info)
1606 {
1607 sector_t nsect = capacity;
1608 sector_t cylinders = nsect;
1609 int heads, sectors_pt;
1610
1611 /*
1612 * We are making up these values; let us keep it simple.
1613 */
1614 heads = 0xff;
1615 sectors_pt = 0x3f; /* Sectors per track */
1616 sector_div(cylinders, heads * sectors_pt);
1617 if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1618 cylinders = 0xffff;
1619
1620 info[0] = heads;
1621 info[1] = sectors_pt;
1622 info[2] = (int)cylinders;
1623
1624 return 0;
1625 }
1626
storvsc_host_reset_handler(struct scsi_cmnd * scmnd)1627 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1628 {
1629 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1630 struct hv_device *device = host_dev->dev;
1631
1632 struct storvsc_device *stor_device;
1633 struct storvsc_cmd_request *request;
1634 struct vstor_packet *vstor_packet;
1635 int ret, t;
1636
1637 stor_device = get_out_stor_device(device);
1638 if (!stor_device)
1639 return FAILED;
1640
1641 request = &stor_device->reset_request;
1642 vstor_packet = &request->vstor_packet;
1643 memset(vstor_packet, 0, sizeof(struct vstor_packet));
1644
1645 init_completion(&request->wait_event);
1646
1647 vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1648 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1649 vstor_packet->vm_srb.path_id = stor_device->path_id;
1650
1651 ret = vmbus_sendpacket(device->channel, vstor_packet,
1652 sizeof(struct vstor_packet),
1653 VMBUS_RQST_RESET,
1654 VM_PKT_DATA_INBAND,
1655 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1656 if (ret != 0)
1657 return FAILED;
1658
1659 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1660 if (t == 0)
1661 return TIMEOUT_ERROR;
1662
1663
1664 /*
1665 * At this point, all outstanding requests in the adapter
1666 * should have been flushed out and return to us
1667 * There is a potential race here where the host may be in
1668 * the process of responding when we return from here.
1669 * Just wait for all in-transit packets to be accounted for
1670 * before we return from here.
1671 */
1672 storvsc_wait_to_drain(stor_device);
1673
1674 return SUCCESS;
1675 }
1676
1677 /*
1678 * The host guarantees to respond to each command, although I/O latencies might
1679 * be unbounded on Azure. Reset the timer unconditionally to give the host a
1680 * chance to perform EH.
1681 */
storvsc_eh_timed_out(struct scsi_cmnd * scmnd)1682 static enum scsi_timeout_action storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1683 {
1684 return SCSI_EH_RESET_TIMER;
1685 }
1686
storvsc_scsi_cmd_ok(struct scsi_cmnd * scmnd)1687 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1688 {
1689 bool allowed = true;
1690 u8 scsi_op = scmnd->cmnd[0];
1691
1692 switch (scsi_op) {
1693 /* the host does not handle WRITE_SAME, log accident usage */
1694 case WRITE_SAME:
1695 /*
1696 * smartd sends this command and the host does not handle
1697 * this. So, don't send it.
1698 */
1699 case SET_WINDOW:
1700 set_host_byte(scmnd, DID_ERROR);
1701 allowed = false;
1702 break;
1703 default:
1704 break;
1705 }
1706 return allowed;
1707 }
1708
storvsc_queuecommand(struct Scsi_Host * host,struct scsi_cmnd * scmnd)1709 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1710 {
1711 int ret;
1712 struct hv_host_device *host_dev = shost_priv(host);
1713 struct hv_device *dev = host_dev->dev;
1714 struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1715 struct scatterlist *sgl;
1716 struct vmscsi_request *vm_srb;
1717 struct vmbus_packet_mpb_array *payload;
1718 u32 payload_sz;
1719 u32 length;
1720
1721 if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1722 /*
1723 * On legacy hosts filter unimplemented commands.
1724 * Future hosts are expected to correctly handle
1725 * unsupported commands. Furthermore, it is
1726 * possible that some of the currently
1727 * unsupported commands maybe supported in
1728 * future versions of the host.
1729 */
1730 if (!storvsc_scsi_cmd_ok(scmnd)) {
1731 scsi_done(scmnd);
1732 return 0;
1733 }
1734 }
1735
1736 /* Setup the cmd request */
1737 cmd_request->cmd = scmnd;
1738
1739 memset(&cmd_request->vstor_packet, 0, sizeof(struct vstor_packet));
1740 vm_srb = &cmd_request->vstor_packet.vm_srb;
1741 vm_srb->time_out_value = 60;
1742
1743 vm_srb->srb_flags |=
1744 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1745
1746 if (scmnd->device->tagged_supported) {
1747 vm_srb->srb_flags |=
1748 (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
1749 vm_srb->queue_tag = SP_UNTAGGED;
1750 vm_srb->queue_action = SRB_SIMPLE_TAG_REQUEST;
1751 }
1752
1753 /* Build the SRB */
1754 switch (scmnd->sc_data_direction) {
1755 case DMA_TO_DEVICE:
1756 vm_srb->data_in = WRITE_TYPE;
1757 vm_srb->srb_flags |= SRB_FLAGS_DATA_OUT;
1758 break;
1759 case DMA_FROM_DEVICE:
1760 vm_srb->data_in = READ_TYPE;
1761 vm_srb->srb_flags |= SRB_FLAGS_DATA_IN;
1762 break;
1763 case DMA_NONE:
1764 vm_srb->data_in = UNKNOWN_TYPE;
1765 vm_srb->srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1766 break;
1767 default:
1768 /*
1769 * This is DMA_BIDIRECTIONAL or something else we are never
1770 * supposed to see here.
1771 */
1772 WARN(1, "Unexpected data direction: %d\n",
1773 scmnd->sc_data_direction);
1774 return -EINVAL;
1775 }
1776
1777
1778 vm_srb->port_number = host_dev->port;
1779 vm_srb->path_id = scmnd->device->channel;
1780 vm_srb->target_id = scmnd->device->id;
1781 vm_srb->lun = scmnd->device->lun;
1782
1783 vm_srb->cdb_length = scmnd->cmd_len;
1784
1785 memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1786
1787 sgl = (struct scatterlist *)scsi_sglist(scmnd);
1788
1789 length = scsi_bufflen(scmnd);
1790 payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1791 payload_sz = 0;
1792
1793 if (scsi_sg_count(scmnd)) {
1794 unsigned long offset_in_hvpg = offset_in_hvpage(sgl->offset);
1795 unsigned int hvpg_count = HVPFN_UP(offset_in_hvpg + length);
1796 struct scatterlist *sg;
1797 unsigned long hvpfn, hvpfns_to_add;
1798 int j, i = 0, sg_count;
1799
1800 payload_sz = (hvpg_count * sizeof(u64) +
1801 sizeof(struct vmbus_packet_mpb_array));
1802
1803 if (hvpg_count > MAX_PAGE_BUFFER_COUNT) {
1804 payload = kzalloc(payload_sz, GFP_ATOMIC);
1805 if (!payload)
1806 return SCSI_MLQUEUE_DEVICE_BUSY;
1807 }
1808
1809 payload->range.len = length;
1810 payload->range.offset = offset_in_hvpg;
1811
1812 sg_count = scsi_dma_map(scmnd);
1813 if (sg_count < 0) {
1814 ret = SCSI_MLQUEUE_DEVICE_BUSY;
1815 goto err_free_payload;
1816 }
1817
1818 for_each_sg(sgl, sg, sg_count, j) {
1819 /*
1820 * Init values for the current sgl entry. hvpfns_to_add
1821 * is in units of Hyper-V size pages. Handling the
1822 * PAGE_SIZE != HV_HYP_PAGE_SIZE case also handles
1823 * values of sgl->offset that are larger than PAGE_SIZE.
1824 * Such offsets are handled even on other than the first
1825 * sgl entry, provided they are a multiple of PAGE_SIZE.
1826 */
1827 hvpfn = HVPFN_DOWN(sg_dma_address(sg));
1828 hvpfns_to_add = HVPFN_UP(sg_dma_address(sg) +
1829 sg_dma_len(sg)) - hvpfn;
1830
1831 /*
1832 * Fill the next portion of the PFN array with
1833 * sequential Hyper-V PFNs for the continguous physical
1834 * memory described by the sgl entry. The end of the
1835 * last sgl should be reached at the same time that
1836 * the PFN array is filled.
1837 */
1838 while (hvpfns_to_add--)
1839 payload->range.pfn_array[i++] = hvpfn++;
1840 }
1841 }
1842
1843 cmd_request->payload = payload;
1844 cmd_request->payload_sz = payload_sz;
1845
1846 /* Invokes the vsc to start an IO */
1847 ret = storvsc_do_io(dev, cmd_request, get_cpu());
1848 put_cpu();
1849
1850 if (ret)
1851 scsi_dma_unmap(scmnd);
1852
1853 if (ret == -EAGAIN) {
1854 /* no more space */
1855 ret = SCSI_MLQUEUE_DEVICE_BUSY;
1856 goto err_free_payload;
1857 }
1858
1859 return 0;
1860
1861 err_free_payload:
1862 if (payload_sz > sizeof(cmd_request->mpb))
1863 kfree(payload);
1864
1865 return ret;
1866 }
1867
1868 static struct scsi_host_template scsi_driver = {
1869 .module = THIS_MODULE,
1870 .name = "storvsc_host_t",
1871 .cmd_size = sizeof(struct storvsc_cmd_request),
1872 .bios_param = storvsc_get_chs,
1873 .queuecommand = storvsc_queuecommand,
1874 .eh_host_reset_handler = storvsc_host_reset_handler,
1875 .proc_name = "storvsc_host",
1876 .eh_timed_out = storvsc_eh_timed_out,
1877 .slave_alloc = storvsc_device_alloc,
1878 .slave_configure = storvsc_device_configure,
1879 .cmd_per_lun = 2048,
1880 .this_id = -1,
1881 /* Ensure there are no gaps in presented sgls */
1882 .virt_boundary_mask = HV_HYP_PAGE_SIZE - 1,
1883 .no_write_same = 1,
1884 .track_queue_depth = 1,
1885 .change_queue_depth = storvsc_change_queue_depth,
1886 };
1887
1888 enum {
1889 SCSI_GUID,
1890 IDE_GUID,
1891 SFC_GUID,
1892 };
1893
1894 static const struct hv_vmbus_device_id id_table[] = {
1895 /* SCSI guid */
1896 { HV_SCSI_GUID,
1897 .driver_data = SCSI_GUID
1898 },
1899 /* IDE guid */
1900 { HV_IDE_GUID,
1901 .driver_data = IDE_GUID
1902 },
1903 /* Fibre Channel GUID */
1904 {
1905 HV_SYNTHFC_GUID,
1906 .driver_data = SFC_GUID
1907 },
1908 { },
1909 };
1910
1911 MODULE_DEVICE_TABLE(vmbus, id_table);
1912
1913 static const struct { guid_t guid; } fc_guid = { HV_SYNTHFC_GUID };
1914
hv_dev_is_fc(struct hv_device * hv_dev)1915 static bool hv_dev_is_fc(struct hv_device *hv_dev)
1916 {
1917 return guid_equal(&fc_guid.guid, &hv_dev->dev_type);
1918 }
1919
storvsc_probe(struct hv_device * device,const struct hv_vmbus_device_id * dev_id)1920 static int storvsc_probe(struct hv_device *device,
1921 const struct hv_vmbus_device_id *dev_id)
1922 {
1923 int ret;
1924 int num_cpus = num_online_cpus();
1925 int num_present_cpus = num_present_cpus();
1926 struct Scsi_Host *host;
1927 struct hv_host_device *host_dev;
1928 bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1929 bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
1930 int target = 0;
1931 struct storvsc_device *stor_device;
1932 int max_sub_channels = 0;
1933 u32 max_xfer_bytes;
1934
1935 /*
1936 * We support sub-channels for storage on SCSI and FC controllers.
1937 * The number of sub-channels offerred is based on the number of
1938 * VCPUs in the guest.
1939 */
1940 if (!dev_is_ide)
1941 max_sub_channels =
1942 (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
1943
1944 scsi_driver.can_queue = max_outstanding_req_per_channel *
1945 (max_sub_channels + 1) *
1946 (100 - ring_avail_percent_lowater) / 100;
1947
1948 host = scsi_host_alloc(&scsi_driver,
1949 sizeof(struct hv_host_device));
1950 if (!host)
1951 return -ENOMEM;
1952
1953 host_dev = shost_priv(host);
1954 memset(host_dev, 0, sizeof(struct hv_host_device));
1955
1956 host_dev->port = host->host_no;
1957 host_dev->dev = device;
1958 host_dev->host = host;
1959
1960
1961 stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
1962 if (!stor_device) {
1963 ret = -ENOMEM;
1964 goto err_out0;
1965 }
1966
1967 stor_device->destroy = false;
1968 init_waitqueue_head(&stor_device->waiting_to_drain);
1969 stor_device->device = device;
1970 stor_device->host = host;
1971 spin_lock_init(&stor_device->lock);
1972 hv_set_drvdata(device, stor_device);
1973 dma_set_min_align_mask(&device->device, HV_HYP_PAGE_SIZE - 1);
1974
1975 stor_device->port_number = host->host_no;
1976 ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size, is_fc);
1977 if (ret)
1978 goto err_out1;
1979
1980 host_dev->path = stor_device->path_id;
1981 host_dev->target = stor_device->target_id;
1982
1983 switch (dev_id->driver_data) {
1984 case SFC_GUID:
1985 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
1986 host->max_id = STORVSC_FC_MAX_TARGETS;
1987 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
1988 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1989 host->transportt = fc_transport_template;
1990 #endif
1991 break;
1992
1993 case SCSI_GUID:
1994 host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
1995 host->max_id = STORVSC_MAX_TARGETS;
1996 host->max_channel = STORVSC_MAX_CHANNELS - 1;
1997 break;
1998
1999 default:
2000 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
2001 host->max_id = STORVSC_IDE_MAX_TARGETS;
2002 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
2003 break;
2004 }
2005 /* max cmd length */
2006 host->max_cmd_len = STORVSC_MAX_CMD_LEN;
2007 /*
2008 * Any reasonable Hyper-V configuration should provide
2009 * max_transfer_bytes value aligning to HV_HYP_PAGE_SIZE,
2010 * protecting it from any weird value.
2011 */
2012 max_xfer_bytes = round_down(stor_device->max_transfer_bytes, HV_HYP_PAGE_SIZE);
2013 if (is_fc)
2014 max_xfer_bytes = min(max_xfer_bytes, STORVSC_FC_MAX_XFER_SIZE);
2015
2016 /* max_hw_sectors_kb */
2017 host->max_sectors = max_xfer_bytes >> 9;
2018 /*
2019 * There are 2 requirements for Hyper-V storvsc sgl segments,
2020 * based on which the below calculation for max segments is
2021 * done:
2022 *
2023 * 1. Except for the first and last sgl segment, all sgl segments
2024 * should be align to HV_HYP_PAGE_SIZE, that also means the
2025 * maximum number of segments in a sgl can be calculated by
2026 * dividing the total max transfer length by HV_HYP_PAGE_SIZE.
2027 *
2028 * 2. Except for the first and last, each entry in the SGL must
2029 * have an offset that is a multiple of HV_HYP_PAGE_SIZE.
2030 */
2031 host->sg_tablesize = (max_xfer_bytes >> HV_HYP_PAGE_SHIFT) + 1;
2032 /*
2033 * For non-IDE disks, the host supports multiple channels.
2034 * Set the number of HW queues we are supporting.
2035 */
2036 if (!dev_is_ide) {
2037 if (storvsc_max_hw_queues > num_present_cpus) {
2038 storvsc_max_hw_queues = 0;
2039 storvsc_log(device, STORVSC_LOGGING_WARN,
2040 "Resetting invalid storvsc_max_hw_queues value to default.\n");
2041 }
2042 if (storvsc_max_hw_queues)
2043 host->nr_hw_queues = storvsc_max_hw_queues;
2044 else
2045 host->nr_hw_queues = num_present_cpus;
2046 }
2047
2048 /*
2049 * Set the error handler work queue.
2050 */
2051 host_dev->handle_error_wq =
2052 alloc_ordered_workqueue("storvsc_error_wq_%d",
2053 0,
2054 host->host_no);
2055 if (!host_dev->handle_error_wq) {
2056 ret = -ENOMEM;
2057 goto err_out2;
2058 }
2059 INIT_WORK(&host_dev->host_scan_work, storvsc_host_scan);
2060 /* Register the HBA and start the scsi bus scan */
2061 ret = scsi_add_host(host, &device->device);
2062 if (ret != 0)
2063 goto err_out3;
2064
2065 if (!dev_is_ide) {
2066 scsi_scan_host(host);
2067 } else {
2068 target = (device->dev_instance.b[5] << 8 |
2069 device->dev_instance.b[4]);
2070 ret = scsi_add_device(host, 0, target, 0);
2071 if (ret)
2072 goto err_out4;
2073 }
2074 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2075 if (host->transportt == fc_transport_template) {
2076 struct fc_rport_identifiers ids = {
2077 .roles = FC_PORT_ROLE_FCP_DUMMY_INITIATOR,
2078 };
2079
2080 fc_host_node_name(host) = stor_device->node_name;
2081 fc_host_port_name(host) = stor_device->port_name;
2082 stor_device->rport = fc_remote_port_add(host, 0, &ids);
2083 if (!stor_device->rport) {
2084 ret = -ENOMEM;
2085 goto err_out4;
2086 }
2087 }
2088 #endif
2089 return 0;
2090
2091 err_out4:
2092 scsi_remove_host(host);
2093
2094 err_out3:
2095 destroy_workqueue(host_dev->handle_error_wq);
2096
2097 err_out2:
2098 /*
2099 * Once we have connected with the host, we would need to
2100 * invoke storvsc_dev_remove() to rollback this state and
2101 * this call also frees up the stor_device; hence the jump around
2102 * err_out1 label.
2103 */
2104 storvsc_dev_remove(device);
2105 goto err_out0;
2106
2107 err_out1:
2108 kfree(stor_device->stor_chns);
2109 kfree(stor_device);
2110
2111 err_out0:
2112 scsi_host_put(host);
2113 return ret;
2114 }
2115
2116 /* Change a scsi target's queue depth */
storvsc_change_queue_depth(struct scsi_device * sdev,int queue_depth)2117 static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth)
2118 {
2119 if (queue_depth > scsi_driver.can_queue)
2120 queue_depth = scsi_driver.can_queue;
2121
2122 return scsi_change_queue_depth(sdev, queue_depth);
2123 }
2124
storvsc_remove(struct hv_device * dev)2125 static void storvsc_remove(struct hv_device *dev)
2126 {
2127 struct storvsc_device *stor_device = hv_get_drvdata(dev);
2128 struct Scsi_Host *host = stor_device->host;
2129 struct hv_host_device *host_dev = shost_priv(host);
2130
2131 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2132 if (host->transportt == fc_transport_template) {
2133 fc_remote_port_delete(stor_device->rport);
2134 fc_remove_host(host);
2135 }
2136 #endif
2137 destroy_workqueue(host_dev->handle_error_wq);
2138 scsi_remove_host(host);
2139 storvsc_dev_remove(dev);
2140 scsi_host_put(host);
2141 }
2142
storvsc_suspend(struct hv_device * hv_dev)2143 static int storvsc_suspend(struct hv_device *hv_dev)
2144 {
2145 struct storvsc_device *stor_device = hv_get_drvdata(hv_dev);
2146 struct Scsi_Host *host = stor_device->host;
2147 struct hv_host_device *host_dev = shost_priv(host);
2148
2149 storvsc_wait_to_drain(stor_device);
2150
2151 drain_workqueue(host_dev->handle_error_wq);
2152
2153 vmbus_close(hv_dev->channel);
2154
2155 kfree(stor_device->stor_chns);
2156 stor_device->stor_chns = NULL;
2157
2158 cpumask_clear(&stor_device->alloced_cpus);
2159
2160 return 0;
2161 }
2162
storvsc_resume(struct hv_device * hv_dev)2163 static int storvsc_resume(struct hv_device *hv_dev)
2164 {
2165 int ret;
2166
2167 ret = storvsc_connect_to_vsp(hv_dev, storvsc_ringbuffer_size,
2168 hv_dev_is_fc(hv_dev));
2169 return ret;
2170 }
2171
2172 static struct hv_driver storvsc_drv = {
2173 .name = KBUILD_MODNAME,
2174 .id_table = id_table,
2175 .probe = storvsc_probe,
2176 .remove = storvsc_remove,
2177 .suspend = storvsc_suspend,
2178 .resume = storvsc_resume,
2179 .driver = {
2180 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
2181 },
2182 };
2183
2184 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2185 static struct fc_function_template fc_transport_functions = {
2186 .show_host_node_name = 1,
2187 .show_host_port_name = 1,
2188 };
2189 #endif
2190
storvsc_drv_init(void)2191 static int __init storvsc_drv_init(void)
2192 {
2193 int ret;
2194
2195 /*
2196 * Divide the ring buffer data size (which is 1 page less
2197 * than the ring buffer size since that page is reserved for
2198 * the ring buffer indices) by the max request size (which is
2199 * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
2200 */
2201 max_outstanding_req_per_channel =
2202 ((storvsc_ringbuffer_size - PAGE_SIZE) /
2203 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
2204 sizeof(struct vstor_packet) + sizeof(u64),
2205 sizeof(u64)));
2206
2207 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2208 fc_transport_template = fc_attach_transport(&fc_transport_functions);
2209 if (!fc_transport_template)
2210 return -ENODEV;
2211 #endif
2212
2213 ret = vmbus_driver_register(&storvsc_drv);
2214
2215 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2216 if (ret)
2217 fc_release_transport(fc_transport_template);
2218 #endif
2219
2220 return ret;
2221 }
2222
storvsc_drv_exit(void)2223 static void __exit storvsc_drv_exit(void)
2224 {
2225 vmbus_driver_unregister(&storvsc_drv);
2226 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2227 fc_release_transport(fc_transport_template);
2228 #endif
2229 }
2230
2231 MODULE_LICENSE("GPL");
2232 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
2233 module_init(storvsc_drv_init);
2234 module_exit(storvsc_drv_exit);
2235
