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