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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. */
67enum 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
88struct 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*/
150static int vmstor_proto_version;
151
152#define STORVSC_LOGGING_NONE 0
153#define STORVSC_LOGGING_ERROR 1
154#define STORVSC_LOGGING_WARN 2
155
156static int logging_level = STORVSC_LOGGING_ERROR;
157module_param(logging_level, int, S_IRUGO|S_IWUSR);
158MODULE_PARM_DESC(logging_level,
159 "Logging level, 0 - None, 1 - Error (default), 2 - Warning.");
160
161static inline bool do_logging(int level)
162{
163 return logging_level >= level;
164}
165
166#define storvsc_log(dev, level, fmt, ...) \
167do { \
168 if (do_logging(level)) \
169 dev_warn(&(dev)->device, fmt, ##__VA_ARGS__); \
170} while (0)
171
172struct 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
210static 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
224struct 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. */
236struct 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
254struct 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 */
299enum 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
332static int storvsc_ringbuffer_size = (128 * 1024);
333static int aligned_ringbuffer_size;
334static u32 max_outstanding_req_per_channel;
335static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth);
336
337static int storvsc_vcpus_per_sub_channel = 4;
338static unsigned int storvsc_max_hw_queues;
339
340module_param(storvsc_ringbuffer_size, int, S_IRUGO);
341MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
342
343module_param(storvsc_max_hw_queues, uint, 0644);
344MODULE_PARM_DESC(storvsc_max_hw_queues, "Maximum number of hardware queues");
345
346module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
347MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
348
349static int ring_avail_percent_lowater = 10;
350module_param(ring_avail_percent_lowater, int, S_IRUGO);
351MODULE_PARM_DESC(ring_avail_percent_lowater,
352 "Select a channel if available ring size > this in percent");
353
354/*
355 * Timeout in seconds for all devices managed by this driver.
356 */
357static int storvsc_timeout = 180;
358
359#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
360static struct scsi_transport_template *fc_transport_template;
361#endif
362
363static struct scsi_host_template scsi_driver;
364static void storvsc_on_channel_callback(void *context);
365
366#define STORVSC_MAX_LUNS_PER_TARGET 255
367#define STORVSC_MAX_TARGETS 2
368#define STORVSC_MAX_CHANNELS 8
369
370#define STORVSC_FC_MAX_LUNS_PER_TARGET 255
371#define STORVSC_FC_MAX_TARGETS 128
372#define STORVSC_FC_MAX_CHANNELS 8
373#define STORVSC_FC_MAX_XFER_SIZE ((u32)(512 * 1024))
374
375#define STORVSC_IDE_MAX_LUNS_PER_TARGET 64
376#define STORVSC_IDE_MAX_TARGETS 1
377#define STORVSC_IDE_MAX_CHANNELS 1
378
379/*
380 * Upper bound on the size of a storvsc packet.
381 */
382#define STORVSC_MAX_PKT_SIZE (sizeof(struct vmpacket_descriptor) +\
383 sizeof(struct vstor_packet))
384
385struct storvsc_cmd_request {
386 struct scsi_cmnd *cmd;
387
388 struct hv_device *device;
389
390 /* Synchronize the request/response if needed */
391 struct completion wait_event;
392
393 struct vmbus_channel_packet_multipage_buffer mpb;
394 struct vmbus_packet_mpb_array *payload;
395 u32 payload_sz;
396
397 struct vstor_packet vstor_packet;
398};
399
400
401/* A storvsc device is a device object that contains a vmbus channel */
402struct storvsc_device {
403 struct hv_device *device;
404
405 bool destroy;
406 bool drain_notify;
407 atomic_t num_outstanding_req;
408 struct Scsi_Host *host;
409
410 wait_queue_head_t waiting_to_drain;
411
412 /*
413 * Each unique Port/Path/Target represents 1 channel ie scsi
414 * controller. In reality, the pathid, targetid is always 0
415 * and the port is set by us
416 */
417 unsigned int port_number;
418 unsigned char path_id;
419 unsigned char target_id;
420
421 /*
422 * Max I/O, the device can support.
423 */
424 u32 max_transfer_bytes;
425 /*
426 * Number of sub-channels we will open.
427 */
428 u16 num_sc;
429 struct vmbus_channel **stor_chns;
430 /*
431 * Mask of CPUs bound to subchannels.
432 */
433 struct cpumask alloced_cpus;
434 /*
435 * Serializes modifications of stor_chns[] from storvsc_do_io()
436 * and storvsc_change_target_cpu().
437 */
438 spinlock_t lock;
439 /* Used for vsc/vsp channel reset process */
440 struct storvsc_cmd_request init_request;
441 struct storvsc_cmd_request reset_request;
442 /*
443 * Currently active port and node names for FC devices.
444 */
445 u64 node_name;
446 u64 port_name;
447#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
448 struct fc_rport *rport;
449#endif
450};
451
452struct hv_host_device {
453 struct hv_device *dev;
454 unsigned int port;
455 unsigned char path;
456 unsigned char target;
457 struct workqueue_struct *handle_error_wq;
458 struct work_struct host_scan_work;
459 struct Scsi_Host *host;
460};
461
462struct storvsc_scan_work {
463 struct work_struct work;
464 struct Scsi_Host *host;
465 u8 lun;
466 u8 tgt_id;
467};
468
469static void storvsc_device_scan(struct work_struct *work)
470{
471 struct storvsc_scan_work *wrk;
472 struct scsi_device *sdev;
473
474 wrk = container_of(work, struct storvsc_scan_work, work);
475
476 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
477 if (!sdev)
478 goto done;
479 scsi_rescan_device(sdev);
480 scsi_device_put(sdev);
481
482done:
483 kfree(wrk);
484}
485
486static void storvsc_host_scan(struct work_struct *work)
487{
488 struct Scsi_Host *host;
489 struct scsi_device *sdev;
490 struct hv_host_device *host_device =
491 container_of(work, struct hv_host_device, host_scan_work);
492
493 host = host_device->host;
494 /*
495 * Before scanning the host, first check to see if any of the
496 * currently known devices have been hot removed. We issue a
497 * "unit ready" command against all currently known devices.
498 * This I/O will result in an error for devices that have been
499 * removed. As part of handling the I/O error, we remove the device.
500 *
501 * When a LUN is added or removed, the host sends us a signal to
502 * scan the host. Thus we are forced to discover the LUNs that
503 * may have been removed this way.
504 */
505 mutex_lock(&host->scan_mutex);
506 shost_for_each_device(sdev, host)
507 scsi_test_unit_ready(sdev, 1, 1, NULL);
508 mutex_unlock(&host->scan_mutex);
509 /*
510 * Now scan the host to discover LUNs that may have been added.
511 */
512 scsi_scan_host(host);
513}
514
515static void storvsc_remove_lun(struct work_struct *work)
516{
517 struct storvsc_scan_work *wrk;
518 struct scsi_device *sdev;
519
520 wrk = container_of(work, struct storvsc_scan_work, work);
521 if (!scsi_host_get(wrk->host))
522 goto done;
523
524 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
525
526 if (sdev) {
527 scsi_remove_device(sdev);
528 scsi_device_put(sdev);
529 }
530 scsi_host_put(wrk->host);
531
532done:
533 kfree(wrk);
534}
535
536
537/*
538 * We can get incoming messages from the host that are not in response to
539 * messages that we have sent out. An example of this would be messages
540 * received by the guest to notify dynamic addition/removal of LUNs. To
541 * deal with potential race conditions where the driver may be in the
542 * midst of being unloaded when we might receive an unsolicited message
543 * from the host, we have implemented a mechanism to gurantee sequential
544 * consistency:
545 *
546 * 1) Once the device is marked as being destroyed, we will fail all
547 * outgoing messages.
548 * 2) We permit incoming messages when the device is being destroyed,
549 * only to properly account for messages already sent out.
550 */
551
552static inline struct storvsc_device *get_out_stor_device(
553 struct hv_device *device)
554{
555 struct storvsc_device *stor_device;
556
557 stor_device = hv_get_drvdata(device);
558
559 if (stor_device && stor_device->destroy)
560 stor_device = NULL;
561
562 return stor_device;
563}
564
565
566static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
567{
568 dev->drain_notify = true;
569 wait_event(dev->waiting_to_drain,
570 atomic_read(&dev->num_outstanding_req) == 0);
571 dev->drain_notify = false;
572}
573
574static inline struct storvsc_device *get_in_stor_device(
575 struct hv_device *device)
576{
577 struct storvsc_device *stor_device;
578
579 stor_device = hv_get_drvdata(device);
580
581 if (!stor_device)
582 goto get_in_err;
583
584 /*
585 * If the device is being destroyed; allow incoming
586 * traffic only to cleanup outstanding requests.
587 */
588
589 if (stor_device->destroy &&
590 (atomic_read(&stor_device->num_outstanding_req) == 0))
591 stor_device = NULL;
592
593get_in_err:
594 return stor_device;
595
596}
597
598static void storvsc_change_target_cpu(struct vmbus_channel *channel, u32 old,
599 u32 new)
600{
601 struct storvsc_device *stor_device;
602 struct vmbus_channel *cur_chn;
603 bool old_is_alloced = false;
604 struct hv_device *device;
605 unsigned long flags;
606 int cpu;
607
608 device = channel->primary_channel ?
609 channel->primary_channel->device_obj
610 : channel->device_obj;
611 stor_device = get_out_stor_device(device);
612 if (!stor_device)
613 return;
614
615 /* See storvsc_do_io() -> get_og_chn(). */
616 spin_lock_irqsave(&stor_device->lock, flags);
617
618 /*
619 * Determines if the storvsc device has other channels assigned to
620 * the "old" CPU to update the alloced_cpus mask and the stor_chns
621 * array.
622 */
623 if (device->channel != channel && device->channel->target_cpu == old) {
624 cur_chn = device->channel;
625 old_is_alloced = true;
626 goto old_is_alloced;
627 }
628 list_for_each_entry(cur_chn, &device->channel->sc_list, sc_list) {
629 if (cur_chn == channel)
630 continue;
631 if (cur_chn->target_cpu == old) {
632 old_is_alloced = true;
633 goto old_is_alloced;
634 }
635 }
636
637old_is_alloced:
638 if (old_is_alloced)
639 WRITE_ONCE(stor_device->stor_chns[old], cur_chn);
640 else
641 cpumask_clear_cpu(old, &stor_device->alloced_cpus);
642
643 /* "Flush" the stor_chns array. */
644 for_each_possible_cpu(cpu) {
645 if (stor_device->stor_chns[cpu] && !cpumask_test_cpu(
646 cpu, &stor_device->alloced_cpus))
647 WRITE_ONCE(stor_device->stor_chns[cpu], NULL);
648 }
649
650 WRITE_ONCE(stor_device->stor_chns[new], channel);
651 cpumask_set_cpu(new, &stor_device->alloced_cpus);
652
653 spin_unlock_irqrestore(&stor_device->lock, flags);
654}
655
656static u64 storvsc_next_request_id(struct vmbus_channel *channel, u64 rqst_addr)
657{
658 struct storvsc_cmd_request *request =
659 (struct storvsc_cmd_request *)(unsigned long)rqst_addr;
660
661 if (rqst_addr == VMBUS_RQST_INIT)
662 return VMBUS_RQST_INIT;
663 if (rqst_addr == VMBUS_RQST_RESET)
664 return VMBUS_RQST_RESET;
665
666 /*
667 * Cannot return an ID of 0, which is reserved for an unsolicited
668 * message from Hyper-V.
669 */
670 return (u64)blk_mq_unique_tag(scsi_cmd_to_rq(request->cmd)) + 1;
671}
672
673static void handle_sc_creation(struct vmbus_channel *new_sc)
674{
675 struct hv_device *device = new_sc->primary_channel->device_obj;
676 struct device *dev = &device->device;
677 struct storvsc_device *stor_device;
678 struct vmstorage_channel_properties props;
679 int ret;
680
681 stor_device = get_out_stor_device(device);
682 if (!stor_device)
683 return;
684
685 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
686 new_sc->max_pkt_size = STORVSC_MAX_PKT_SIZE;
687
688 new_sc->next_request_id_callback = storvsc_next_request_id;
689
690 ret = vmbus_open(new_sc,
691 aligned_ringbuffer_size,
692 aligned_ringbuffer_size,
693 (void *)&props,
694 sizeof(struct vmstorage_channel_properties),
695 storvsc_on_channel_callback, new_sc);
696
697 /* In case vmbus_open() fails, we don't use the sub-channel. */
698 if (ret != 0) {
699 dev_err(dev, "Failed to open sub-channel: err=%d\n", ret);
700 return;
701 }
702
703 new_sc->change_target_cpu_callback = storvsc_change_target_cpu;
704
705 /* Add the sub-channel to the array of available channels. */
706 stor_device->stor_chns[new_sc->target_cpu] = new_sc;
707 cpumask_set_cpu(new_sc->target_cpu, &stor_device->alloced_cpus);
708}
709
710static void handle_multichannel_storage(struct hv_device *device, int max_chns)
711{
712 struct device *dev = &device->device;
713 struct storvsc_device *stor_device;
714 int num_sc;
715 struct storvsc_cmd_request *request;
716 struct vstor_packet *vstor_packet;
717 int ret, t;
718
719 /*
720 * If the number of CPUs is artificially restricted, such as
721 * with maxcpus=1 on the kernel boot line, Hyper-V could offer
722 * sub-channels >= the number of CPUs. These sub-channels
723 * should not be created. The primary channel is already created
724 * and assigned to one CPU, so check against # CPUs - 1.
725 */
726 num_sc = min((int)(num_online_cpus() - 1), max_chns);
727 if (!num_sc)
728 return;
729
730 stor_device = get_out_stor_device(device);
731 if (!stor_device)
732 return;
733
734 stor_device->num_sc = num_sc;
735 request = &stor_device->init_request;
736 vstor_packet = &request->vstor_packet;
737
738 /*
739 * Establish a handler for dealing with subchannels.
740 */
741 vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
742
743 /*
744 * Request the host to create sub-channels.
745 */
746 memset(request, 0, sizeof(struct storvsc_cmd_request));
747 init_completion(&request->wait_event);
748 vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
749 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
750 vstor_packet->sub_channel_count = num_sc;
751
752 ret = vmbus_sendpacket(device->channel, vstor_packet,
753 sizeof(struct vstor_packet),
754 VMBUS_RQST_INIT,
755 VM_PKT_DATA_INBAND,
756 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
757
758 if (ret != 0) {
759 dev_err(dev, "Failed to create sub-channel: err=%d\n", ret);
760 return;
761 }
762
763 t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
764 if (t == 0) {
765 dev_err(dev, "Failed to create sub-channel: timed out\n");
766 return;
767 }
768
769 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
770 vstor_packet->status != 0) {
771 dev_err(dev, "Failed to create sub-channel: op=%d, sts=%d\n",
772 vstor_packet->operation, vstor_packet->status);
773 return;
774 }
775
776 /*
777 * We need to do nothing here, because vmbus_process_offer()
778 * invokes channel->sc_creation_callback, which will open and use
779 * the sub-channel(s).
780 */
781}
782
783static void cache_wwn(struct storvsc_device *stor_device,
784 struct vstor_packet *vstor_packet)
785{
786 /*
787 * Cache the currently active port and node ww names.
788 */
789 if (vstor_packet->wwn_packet.primary_active) {
790 stor_device->node_name =
791 wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
792 stor_device->port_name =
793 wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
794 } else {
795 stor_device->node_name =
796 wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
797 stor_device->port_name =
798 wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
799 }
800}
801
802
803static int storvsc_execute_vstor_op(struct hv_device *device,
804 struct storvsc_cmd_request *request,
805 bool status_check)
806{
807 struct storvsc_device *stor_device;
808 struct vstor_packet *vstor_packet;
809 int ret, t;
810
811 stor_device = get_out_stor_device(device);
812 if (!stor_device)
813 return -ENODEV;
814
815 vstor_packet = &request->vstor_packet;
816
817 init_completion(&request->wait_event);
818 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
819
820 ret = vmbus_sendpacket(device->channel, vstor_packet,
821 sizeof(struct vstor_packet),
822 VMBUS_RQST_INIT,
823 VM_PKT_DATA_INBAND,
824 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
825 if (ret != 0)
826 return ret;
827
828 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
829 if (t == 0)
830 return -ETIMEDOUT;
831
832 if (!status_check)
833 return ret;
834
835 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
836 vstor_packet->status != 0)
837 return -EINVAL;
838
839 return ret;
840}
841
842static int storvsc_channel_init(struct hv_device *device, bool is_fc)
843{
844 struct storvsc_device *stor_device;
845 struct storvsc_cmd_request *request;
846 struct vstor_packet *vstor_packet;
847 int ret, i;
848 int max_chns;
849 bool process_sub_channels = false;
850
851 stor_device = get_out_stor_device(device);
852 if (!stor_device)
853 return -ENODEV;
854
855 request = &stor_device->init_request;
856 vstor_packet = &request->vstor_packet;
857
858 /*
859 * Now, initiate the vsc/vsp initialization protocol on the open
860 * channel
861 */
862 memset(request, 0, sizeof(struct storvsc_cmd_request));
863 vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
864 ret = storvsc_execute_vstor_op(device, request, true);
865 if (ret)
866 return ret;
867 /*
868 * Query host supported protocol version.
869 */
870
871 for (i = 0; i < ARRAY_SIZE(protocol_version); i++) {
872 /* reuse the packet for version range supported */
873 memset(vstor_packet, 0, sizeof(struct vstor_packet));
874 vstor_packet->operation =
875 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
876
877 vstor_packet->version.major_minor = protocol_version[i];
878
879 /*
880 * The revision number is only used in Windows; set it to 0.
881 */
882 vstor_packet->version.revision = 0;
883 ret = storvsc_execute_vstor_op(device, request, false);
884 if (ret != 0)
885 return ret;
886
887 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
888 return -EINVAL;
889
890 if (vstor_packet->status == 0) {
891 vmstor_proto_version = protocol_version[i];
892
893 break;
894 }
895 }
896
897 if (vstor_packet->status != 0) {
898 dev_err(&device->device, "Obsolete Hyper-V version\n");
899 return -EINVAL;
900 }
901
902
903 memset(vstor_packet, 0, sizeof(struct vstor_packet));
904 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
905 ret = storvsc_execute_vstor_op(device, request, true);
906 if (ret != 0)
907 return ret;
908
909 /*
910 * Check to see if multi-channel support is there.
911 * Hosts that implement protocol version of 5.1 and above
912 * support multi-channel.
913 */
914 max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
915
916 /*
917 * Allocate state to manage the sub-channels.
918 * We allocate an array based on the numbers of possible CPUs
919 * (Hyper-V does not support cpu online/offline).
920 * This Array will be sparseley populated with unique
921 * channels - primary + sub-channels.
922 * We will however populate all the slots to evenly distribute
923 * the load.
924 */
925 stor_device->stor_chns = kcalloc(num_possible_cpus(), sizeof(void *),
926 GFP_KERNEL);
927 if (stor_device->stor_chns == NULL)
928 return -ENOMEM;
929
930 device->channel->change_target_cpu_callback = storvsc_change_target_cpu;
931
932 stor_device->stor_chns[device->channel->target_cpu] = device->channel;
933 cpumask_set_cpu(device->channel->target_cpu,
934 &stor_device->alloced_cpus);
935
936 if (vstor_packet->storage_channel_properties.flags &
937 STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
938 process_sub_channels = true;
939
940 stor_device->max_transfer_bytes =
941 vstor_packet->storage_channel_properties.max_transfer_bytes;
942
943 if (!is_fc)
944 goto done;
945
946 /*
947 * For FC devices retrieve FC HBA data.
948 */
949 memset(vstor_packet, 0, sizeof(struct vstor_packet));
950 vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
951 ret = storvsc_execute_vstor_op(device, request, true);
952 if (ret != 0)
953 return ret;
954
955 /*
956 * Cache the currently active port and node ww names.
957 */
958 cache_wwn(stor_device, vstor_packet);
959
960done:
961
962 memset(vstor_packet, 0, sizeof(struct vstor_packet));
963 vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
964 ret = storvsc_execute_vstor_op(device, request, true);
965 if (ret != 0)
966 return ret;
967
968 if (process_sub_channels)
969 handle_multichannel_storage(device, max_chns);
970
971 return ret;
972}
973
974static void storvsc_handle_error(struct vmscsi_request *vm_srb,
975 struct scsi_cmnd *scmnd,
976 struct Scsi_Host *host,
977 u8 asc, u8 ascq)
978{
979 struct storvsc_scan_work *wrk;
980 void (*process_err_fn)(struct work_struct *work);
981 struct hv_host_device *host_dev = shost_priv(host);
982
983 switch (SRB_STATUS(vm_srb->srb_status)) {
984 case SRB_STATUS_ERROR:
985 case SRB_STATUS_ABORTED:
986 case SRB_STATUS_INVALID_REQUEST:
987 case SRB_STATUS_INTERNAL_ERROR:
988 case SRB_STATUS_TIMEOUT:
989 case SRB_STATUS_SELECTION_TIMEOUT:
990 case SRB_STATUS_BUS_RESET:
991 case SRB_STATUS_DATA_OVERRUN:
992 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID) {
993 /* Check for capacity change */
994 if ((asc == 0x2a) && (ascq == 0x9)) {
995 process_err_fn = storvsc_device_scan;
996 /* Retry the I/O that triggered this. */
997 set_host_byte(scmnd, DID_REQUEUE);
998 goto do_work;
999 }
1000
1001 /*
1002 * Check for "Operating parameters have changed"
1003 * due to Hyper-V changing the VHD/VHDX BlockSize
1004 * when adding/removing a differencing disk. This
1005 * causes discard_granularity to change, so do a
1006 * rescan to pick up the new granularity. We don't
1007 * want scsi_report_sense() to output a message
1008 * that a sysadmin wouldn't know what to do with.
1009 */
1010 if ((asc == 0x3f) && (ascq != 0x03) &&
1011 (ascq != 0x0e)) {
1012 process_err_fn = storvsc_device_scan;
1013 set_host_byte(scmnd, DID_REQUEUE);
1014 goto do_work;
1015 }
1016
1017 /*
1018 * Otherwise, let upper layer deal with the
1019 * error when sense message is present
1020 */
1021 return;
1022 }
1023
1024 /*
1025 * If there is an error; offline the device since all
1026 * error recovery strategies would have already been
1027 * deployed on the host side. However, if the command
1028 * were a pass-through command deal with it appropriately.
1029 */
1030 switch (scmnd->cmnd[0]) {
1031 case ATA_16:
1032 case ATA_12:
1033 set_host_byte(scmnd, DID_PASSTHROUGH);
1034 break;
1035 /*
1036 * On some Hyper-V hosts TEST_UNIT_READY command can
1037 * return SRB_STATUS_ERROR. Let the upper level code
1038 * deal with it based on the sense information.
1039 */
1040 case TEST_UNIT_READY:
1041 break;
1042 default:
1043 set_host_byte(scmnd, DID_ERROR);
1044 }
1045 return;
1046
1047 case SRB_STATUS_INVALID_LUN:
1048 set_host_byte(scmnd, DID_NO_CONNECT);
1049 process_err_fn = storvsc_remove_lun;
1050 goto do_work;
1051
1052 }
1053 return;
1054
1055do_work:
1056 /*
1057 * We need to schedule work to process this error; schedule it.
1058 */
1059 wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1060 if (!wrk) {
1061 set_host_byte(scmnd, DID_BAD_TARGET);
1062 return;
1063 }
1064
1065 wrk->host = host;
1066 wrk->lun = vm_srb->lun;
1067 wrk->tgt_id = vm_srb->target_id;
1068 INIT_WORK(&wrk->work, process_err_fn);
1069 queue_work(host_dev->handle_error_wq, &wrk->work);
1070}
1071
1072
1073static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
1074 struct storvsc_device *stor_dev)
1075{
1076 struct scsi_cmnd *scmnd = cmd_request->cmd;
1077 struct scsi_sense_hdr sense_hdr;
1078 struct vmscsi_request *vm_srb;
1079 u32 data_transfer_length;
1080 struct Scsi_Host *host;
1081 u32 payload_sz = cmd_request->payload_sz;
1082 void *payload = cmd_request->payload;
1083 bool sense_ok;
1084
1085 host = stor_dev->host;
1086
1087 vm_srb = &cmd_request->vstor_packet.vm_srb;
1088 data_transfer_length = vm_srb->data_transfer_length;
1089
1090 scmnd->result = vm_srb->scsi_status;
1091
1092 if (scmnd->result) {
1093 sense_ok = scsi_normalize_sense(scmnd->sense_buffer,
1094 SCSI_SENSE_BUFFERSIZE, &sense_hdr);
1095
1096 if (sense_ok && do_logging(STORVSC_LOGGING_WARN))
1097 scsi_print_sense_hdr(scmnd->device, "storvsc",
1098 &sense_hdr);
1099 }
1100
1101 if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
1102 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
1103 sense_hdr.ascq);
1104 /*
1105 * The Windows driver set data_transfer_length on
1106 * SRB_STATUS_DATA_OVERRUN. On other errors, this value
1107 * is untouched. In these cases we set it to 0.
1108 */
1109 if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
1110 data_transfer_length = 0;
1111 }
1112
1113 /* Validate data_transfer_length (from Hyper-V) */
1114 if (data_transfer_length > cmd_request->payload->range.len)
1115 data_transfer_length = cmd_request->payload->range.len;
1116
1117 scsi_set_resid(scmnd,
1118 cmd_request->payload->range.len - data_transfer_length);
1119
1120 scsi_done(scmnd);
1121
1122 if (payload_sz >
1123 sizeof(struct vmbus_channel_packet_multipage_buffer))
1124 kfree(payload);
1125}
1126
1127static void storvsc_on_io_completion(struct storvsc_device *stor_device,
1128 struct vstor_packet *vstor_packet,
1129 struct storvsc_cmd_request *request)
1130{
1131 struct vstor_packet *stor_pkt;
1132 struct hv_device *device = stor_device->device;
1133
1134 stor_pkt = &request->vstor_packet;
1135
1136 /*
1137 * The current SCSI handling on the host side does
1138 * not correctly handle:
1139 * INQUIRY command with page code parameter set to 0x80
1140 * MODE_SENSE command with cmd[2] == 0x1c
1141 *
1142 * Setup srb and scsi status so this won't be fatal.
1143 * We do this so we can distinguish truly fatal failues
1144 * (srb status == 0x4) and off-line the device in that case.
1145 */
1146
1147 if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1148 (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1149 vstor_packet->vm_srb.scsi_status = 0;
1150 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1151 }
1152
1153 /* Copy over the status...etc */
1154 stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1155 stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1156
1157 /*
1158 * Copy over the sense_info_length, but limit to the known max
1159 * size if Hyper-V returns a bad value.
1160 */
1161 stor_pkt->vm_srb.sense_info_length = min_t(u8, STORVSC_SENSE_BUFFER_SIZE,
1162 vstor_packet->vm_srb.sense_info_length);
1163
1164 if (vstor_packet->vm_srb.scsi_status != 0 ||
1165 vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS) {
1166
1167 /*
1168 * Log TEST_UNIT_READY errors only as warnings. Hyper-V can
1169 * return errors when detecting devices using TEST_UNIT_READY,
1170 * and logging these as errors produces unhelpful noise.
1171 */
1172 int loglevel = (stor_pkt->vm_srb.cdb[0] == TEST_UNIT_READY) ?
1173 STORVSC_LOGGING_WARN : STORVSC_LOGGING_ERROR;
1174
1175 storvsc_log(device, loglevel,
1176 "tag#%d cmd 0x%x status: scsi 0x%x srb 0x%x hv 0x%x\n",
1177 scsi_cmd_to_rq(request->cmd)->tag,
1178 stor_pkt->vm_srb.cdb[0],
1179 vstor_packet->vm_srb.scsi_status,
1180 vstor_packet->vm_srb.srb_status,
1181 vstor_packet->status);
1182 }
1183
1184 if (vstor_packet->vm_srb.scsi_status == SAM_STAT_CHECK_CONDITION &&
1185 (vstor_packet->vm_srb.srb_status & SRB_STATUS_AUTOSENSE_VALID))
1186 memcpy(request->cmd->sense_buffer,
1187 vstor_packet->vm_srb.sense_data,
1188 stor_pkt->vm_srb.sense_info_length);
1189
1190 stor_pkt->vm_srb.data_transfer_length =
1191 vstor_packet->vm_srb.data_transfer_length;
1192
1193 storvsc_command_completion(request, stor_device);
1194
1195 if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1196 stor_device->drain_notify)
1197 wake_up(&stor_device->waiting_to_drain);
1198}
1199
1200static void storvsc_on_receive(struct storvsc_device *stor_device,
1201 struct vstor_packet *vstor_packet,
1202 struct storvsc_cmd_request *request)
1203{
1204 struct hv_host_device *host_dev;
1205 switch (vstor_packet->operation) {
1206 case VSTOR_OPERATION_COMPLETE_IO:
1207 storvsc_on_io_completion(stor_device, vstor_packet, request);
1208 break;
1209
1210 case VSTOR_OPERATION_REMOVE_DEVICE:
1211 case VSTOR_OPERATION_ENUMERATE_BUS:
1212 host_dev = shost_priv(stor_device->host);
1213 queue_work(
1214 host_dev->handle_error_wq, &host_dev->host_scan_work);
1215 break;
1216
1217 case VSTOR_OPERATION_FCHBA_DATA:
1218 cache_wwn(stor_device, vstor_packet);
1219#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1220 fc_host_node_name(stor_device->host) = stor_device->node_name;
1221 fc_host_port_name(stor_device->host) = stor_device->port_name;
1222#endif
1223 break;
1224 default:
1225 break;
1226 }
1227}
1228
1229static void storvsc_on_channel_callback(void *context)
1230{
1231 struct vmbus_channel *channel = (struct vmbus_channel *)context;
1232 const struct vmpacket_descriptor *desc;
1233 struct hv_device *device;
1234 struct storvsc_device *stor_device;
1235 struct Scsi_Host *shost;
1236 unsigned long time_limit = jiffies + msecs_to_jiffies(CALLBACK_TIMEOUT);
1237
1238 if (channel->primary_channel != NULL)
1239 device = channel->primary_channel->device_obj;
1240 else
1241 device = channel->device_obj;
1242
1243 stor_device = get_in_stor_device(device);
1244 if (!stor_device)
1245 return;
1246
1247 shost = stor_device->host;
1248
1249 foreach_vmbus_pkt(desc, channel) {
1250 struct vstor_packet *packet = hv_pkt_data(desc);
1251 struct storvsc_cmd_request *request = NULL;
1252 u32 pktlen = hv_pkt_datalen(desc);
1253 u64 rqst_id = desc->trans_id;
1254 u32 minlen = rqst_id ? sizeof(struct vstor_packet) :
1255 sizeof(enum vstor_packet_operation);
1256
1257 if (unlikely(time_after(jiffies, time_limit))) {
1258 hv_pkt_iter_close(channel);
1259 return;
1260 }
1261
1262 if (pktlen < minlen) {
1263 dev_err(&device->device,
1264 "Invalid pkt: id=%llu, len=%u, minlen=%u\n",
1265 rqst_id, pktlen, minlen);
1266 continue;
1267 }
1268
1269 if (rqst_id == VMBUS_RQST_INIT) {
1270 request = &stor_device->init_request;
1271 } else if (rqst_id == VMBUS_RQST_RESET) {
1272 request = &stor_device->reset_request;
1273 } else {
1274 /* Hyper-V can send an unsolicited message with ID of 0 */
1275 if (rqst_id == 0) {
1276 /*
1277 * storvsc_on_receive() looks at the vstor_packet in the message
1278 * from the ring buffer.
1279 *
1280 * - If the operation in the vstor_packet is COMPLETE_IO, then
1281 * we call storvsc_on_io_completion(), and dereference the
1282 * guest memory address. Make sure we don't call
1283 * storvsc_on_io_completion() with a guest memory address
1284 * that is zero if Hyper-V were to construct and send such
1285 * a bogus packet.
1286 *
1287 * - If the operation in the vstor_packet is FCHBA_DATA, then
1288 * we call cache_wwn(), and access the data payload area of
1289 * the packet (wwn_packet); however, there is no guarantee
1290 * that the packet is big enough to contain such area.
1291 * Future-proof the code by rejecting such a bogus packet.
1292 */
1293 if (packet->operation == VSTOR_OPERATION_COMPLETE_IO ||
1294 packet->operation == VSTOR_OPERATION_FCHBA_DATA) {
1295 dev_err(&device->device, "Invalid packet with ID of 0\n");
1296 continue;
1297 }
1298 } else {
1299 struct scsi_cmnd *scmnd;
1300
1301 /* Transaction 'rqst_id' corresponds to tag 'rqst_id - 1' */
1302 scmnd = scsi_host_find_tag(shost, rqst_id - 1);
1303 if (scmnd == NULL) {
1304 dev_err(&device->device, "Incorrect transaction ID\n");
1305 continue;
1306 }
1307 request = (struct storvsc_cmd_request *)scsi_cmd_priv(scmnd);
1308 scsi_dma_unmap(scmnd);
1309 }
1310
1311 storvsc_on_receive(stor_device, packet, request);
1312 continue;
1313 }
1314
1315 memcpy(&request->vstor_packet, packet,
1316 sizeof(struct vstor_packet));
1317 complete(&request->wait_event);
1318 }
1319}
1320
1321static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
1322 bool is_fc)
1323{
1324 struct vmstorage_channel_properties props;
1325 int ret;
1326
1327 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1328
1329 device->channel->max_pkt_size = STORVSC_MAX_PKT_SIZE;
1330 device->channel->next_request_id_callback = storvsc_next_request_id;
1331
1332 ret = vmbus_open(device->channel,
1333 ring_size,
1334 ring_size,
1335 (void *)&props,
1336 sizeof(struct vmstorage_channel_properties),
1337 storvsc_on_channel_callback, device->channel);
1338
1339 if (ret != 0)
1340 return ret;
1341
1342 ret = storvsc_channel_init(device, is_fc);
1343
1344 return ret;
1345}
1346
1347static int storvsc_dev_remove(struct hv_device *device)
1348{
1349 struct storvsc_device *stor_device;
1350
1351 stor_device = hv_get_drvdata(device);
1352
1353 stor_device->destroy = true;
1354
1355 /* Make sure flag is set before waiting */
1356 wmb();
1357
1358 /*
1359 * At this point, all outbound traffic should be disable. We
1360 * only allow inbound traffic (responses) to proceed so that
1361 * outstanding requests can be completed.
1362 */
1363
1364 storvsc_wait_to_drain(stor_device);
1365
1366 /*
1367 * Since we have already drained, we don't need to busy wait
1368 * as was done in final_release_stor_device()
1369 * Note that we cannot set the ext pointer to NULL until
1370 * we have drained - to drain the outgoing packets, we need to
1371 * allow incoming packets.
1372 */
1373 hv_set_drvdata(device, NULL);
1374
1375 /* Close the channel */
1376 vmbus_close(device->channel);
1377
1378 kfree(stor_device->stor_chns);
1379 kfree(stor_device);
1380 return 0;
1381}
1382
1383static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device,
1384 u16 q_num)
1385{
1386 u16 slot = 0;
1387 u16 hash_qnum;
1388 const struct cpumask *node_mask;
1389 int num_channels, tgt_cpu;
1390
1391 if (stor_device->num_sc == 0) {
1392 stor_device->stor_chns[q_num] = stor_device->device->channel;
1393 return stor_device->device->channel;
1394 }
1395
1396 /*
1397 * Our channel array is sparsley populated and we
1398 * initiated I/O on a processor/hw-q that does not
1399 * currently have a designated channel. Fix this.
1400 * The strategy is simple:
1401 * I. Ensure NUMA locality
1402 * II. Distribute evenly (best effort)
1403 */
1404
1405 node_mask = cpumask_of_node(cpu_to_node(q_num));
1406
1407 num_channels = 0;
1408 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1409 if (cpumask_test_cpu(tgt_cpu, node_mask))
1410 num_channels++;
1411 }
1412 if (num_channels == 0) {
1413 stor_device->stor_chns[q_num] = stor_device->device->channel;
1414 return stor_device->device->channel;
1415 }
1416
1417 hash_qnum = q_num;
1418 while (hash_qnum >= num_channels)
1419 hash_qnum -= num_channels;
1420
1421 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1422 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1423 continue;
1424 if (slot == hash_qnum)
1425 break;
1426 slot++;
1427 }
1428
1429 stor_device->stor_chns[q_num] = stor_device->stor_chns[tgt_cpu];
1430
1431 return stor_device->stor_chns[q_num];
1432}
1433
1434
1435static int storvsc_do_io(struct hv_device *device,
1436 struct storvsc_cmd_request *request, u16 q_num)
1437{
1438 struct storvsc_device *stor_device;
1439 struct vstor_packet *vstor_packet;
1440 struct vmbus_channel *outgoing_channel, *channel;
1441 unsigned long flags;
1442 int ret = 0;
1443 const struct cpumask *node_mask;
1444 int tgt_cpu;
1445
1446 vstor_packet = &request->vstor_packet;
1447 stor_device = get_out_stor_device(device);
1448
1449 if (!stor_device)
1450 return -ENODEV;
1451
1452
1453 request->device = device;
1454 /*
1455 * Select an appropriate channel to send the request out.
1456 */
1457 /* See storvsc_change_target_cpu(). */
1458 outgoing_channel = READ_ONCE(stor_device->stor_chns[q_num]);
1459 if (outgoing_channel != NULL) {
1460 if (outgoing_channel->target_cpu == q_num) {
1461 /*
1462 * Ideally, we want to pick a different channel if
1463 * available on the same NUMA node.
1464 */
1465 node_mask = cpumask_of_node(cpu_to_node(q_num));
1466 for_each_cpu_wrap(tgt_cpu,
1467 &stor_device->alloced_cpus, q_num + 1) {
1468 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1469 continue;
1470 if (tgt_cpu == q_num)
1471 continue;
1472 channel = READ_ONCE(
1473 stor_device->stor_chns[tgt_cpu]);
1474 if (channel == NULL)
1475 continue;
1476 if (hv_get_avail_to_write_percent(
1477 &channel->outbound)
1478 > ring_avail_percent_lowater) {
1479 outgoing_channel = channel;
1480 goto found_channel;
1481 }
1482 }
1483
1484 /*
1485 * All the other channels on the same NUMA node are
1486 * busy. Try to use the channel on the current CPU
1487 */
1488 if (hv_get_avail_to_write_percent(
1489 &outgoing_channel->outbound)
1490 > ring_avail_percent_lowater)
1491 goto found_channel;
1492
1493 /*
1494 * If we reach here, all the channels on the current
1495 * NUMA node are busy. Try to find a channel in
1496 * other NUMA nodes
1497 */
1498 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1499 if (cpumask_test_cpu(tgt_cpu, node_mask))
1500 continue;
1501 channel = READ_ONCE(
1502 stor_device->stor_chns[tgt_cpu]);
1503 if (channel == NULL)
1504 continue;
1505 if (hv_get_avail_to_write_percent(
1506 &channel->outbound)
1507 > ring_avail_percent_lowater) {
1508 outgoing_channel = channel;
1509 goto found_channel;
1510 }
1511 }
1512 }
1513 } else {
1514 spin_lock_irqsave(&stor_device->lock, flags);
1515 outgoing_channel = stor_device->stor_chns[q_num];
1516 if (outgoing_channel != NULL) {
1517 spin_unlock_irqrestore(&stor_device->lock, flags);
1518 goto found_channel;
1519 }
1520 outgoing_channel = get_og_chn(stor_device, q_num);
1521 spin_unlock_irqrestore(&stor_device->lock, flags);
1522 }
1523
1524found_channel:
1525 vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1526
1527 vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
1528
1529
1530 vstor_packet->vm_srb.sense_info_length = STORVSC_SENSE_BUFFER_SIZE;
1531
1532
1533 vstor_packet->vm_srb.data_transfer_length =
1534 request->payload->range.len;
1535
1536 vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1537
1538 if (request->payload->range.len) {
1539
1540 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1541 request->payload, request->payload_sz,
1542 vstor_packet,
1543 sizeof(struct vstor_packet),
1544 (unsigned long)request);
1545 } else {
1546 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1547 sizeof(struct vstor_packet),
1548 (unsigned long)request,
1549 VM_PKT_DATA_INBAND,
1550 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1551 }
1552
1553 if (ret != 0)
1554 return ret;
1555
1556 atomic_inc(&stor_device->num_outstanding_req);
1557
1558 return ret;
1559}
1560
1561static int storvsc_device_alloc(struct scsi_device *sdevice)
1562{
1563 /*
1564 * Set blist flag to permit the reading of the VPD pages even when
1565 * the target may claim SPC-2 compliance. MSFT targets currently
1566 * claim SPC-2 compliance while they implement post SPC-2 features.
1567 * With this flag we can correctly handle WRITE_SAME_16 issues.
1568 *
1569 * Hypervisor reports SCSI_UNKNOWN type for DVD ROM device but
1570 * still supports REPORT LUN.
1571 */
1572 sdevice->sdev_bflags = BLIST_REPORTLUN2 | BLIST_TRY_VPD_PAGES;
1573
1574 return 0;
1575}
1576
1577static int storvsc_device_configure(struct scsi_device *sdevice)
1578{
1579 blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1580
1581 /* storvsc devices don't support MAINTENANCE_IN SCSI cmd */
1582 sdevice->no_report_opcodes = 1;
1583 sdevice->no_write_same = 1;
1584
1585 /*
1586 * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1587 * if the device is a MSFT virtual device. If the host is
1588 * WIN10 or newer, allow write_same.
1589 */
1590 if (!strncmp(sdevice->vendor, "Msft", 4)) {
1591 switch (vmstor_proto_version) {
1592 case VMSTOR_PROTO_VERSION_WIN8:
1593 case VMSTOR_PROTO_VERSION_WIN8_1:
1594 sdevice->scsi_level = SCSI_SPC_3;
1595 break;
1596 }
1597
1598 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1599 sdevice->no_write_same = 0;
1600 }
1601
1602 return 0;
1603}
1604
1605static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1606 sector_t capacity, int *info)
1607{
1608 sector_t nsect = capacity;
1609 sector_t cylinders = nsect;
1610 int heads, sectors_pt;
1611
1612 /*
1613 * We are making up these values; let us keep it simple.
1614 */
1615 heads = 0xff;
1616 sectors_pt = 0x3f; /* Sectors per track */
1617 sector_div(cylinders, heads * sectors_pt);
1618 if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1619 cylinders = 0xffff;
1620
1621 info[0] = heads;
1622 info[1] = sectors_pt;
1623 info[2] = (int)cylinders;
1624
1625 return 0;
1626}
1627
1628static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1629{
1630 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1631 struct hv_device *device = host_dev->dev;
1632
1633 struct storvsc_device *stor_device;
1634 struct storvsc_cmd_request *request;
1635 struct vstor_packet *vstor_packet;
1636 int ret, t;
1637
1638 stor_device = get_out_stor_device(device);
1639 if (!stor_device)
1640 return FAILED;
1641
1642 request = &stor_device->reset_request;
1643 vstor_packet = &request->vstor_packet;
1644 memset(vstor_packet, 0, sizeof(struct vstor_packet));
1645
1646 init_completion(&request->wait_event);
1647
1648 vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1649 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1650 vstor_packet->vm_srb.path_id = stor_device->path_id;
1651
1652 ret = vmbus_sendpacket(device->channel, vstor_packet,
1653 sizeof(struct vstor_packet),
1654 VMBUS_RQST_RESET,
1655 VM_PKT_DATA_INBAND,
1656 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1657 if (ret != 0)
1658 return FAILED;
1659
1660 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1661 if (t == 0)
1662 return TIMEOUT_ERROR;
1663
1664
1665 /*
1666 * At this point, all outstanding requests in the adapter
1667 * should have been flushed out and return to us
1668 * There is a potential race here where the host may be in
1669 * the process of responding when we return from here.
1670 * Just wait for all in-transit packets to be accounted for
1671 * before we return from here.
1672 */
1673 storvsc_wait_to_drain(stor_device);
1674
1675 return SUCCESS;
1676}
1677
1678/*
1679 * The host guarantees to respond to each command, although I/O latencies might
1680 * be unbounded on Azure. Reset the timer unconditionally to give the host a
1681 * chance to perform EH.
1682 */
1683static enum scsi_timeout_action storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1684{
1685 return SCSI_EH_RESET_TIMER;
1686}
1687
1688static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1689{
1690 bool allowed = true;
1691 u8 scsi_op = scmnd->cmnd[0];
1692
1693 switch (scsi_op) {
1694 /* the host does not handle WRITE_SAME, log accident usage */
1695 case WRITE_SAME:
1696 /*
1697 * smartd sends this command and the host does not handle
1698 * this. So, don't send it.
1699 */
1700 case SET_WINDOW:
1701 set_host_byte(scmnd, DID_ERROR);
1702 allowed = false;
1703 break;
1704 default:
1705 break;
1706 }
1707 return allowed;
1708}
1709
1710static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1711{
1712 int ret;
1713 struct hv_host_device *host_dev = shost_priv(host);
1714 struct hv_device *dev = host_dev->dev;
1715 struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1716 struct scatterlist *sgl;
1717 struct vmscsi_request *vm_srb;
1718 struct vmbus_packet_mpb_array *payload;
1719 u32 payload_sz;
1720 u32 length;
1721
1722 if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1723 /*
1724 * On legacy hosts filter unimplemented commands.
1725 * Future hosts are expected to correctly handle
1726 * unsupported commands. Furthermore, it is
1727 * possible that some of the currently
1728 * unsupported commands maybe supported in
1729 * future versions of the host.
1730 */
1731 if (!storvsc_scsi_cmd_ok(scmnd)) {
1732 scsi_done(scmnd);
1733 return 0;
1734 }
1735 }
1736
1737 /* Setup the cmd request */
1738 cmd_request->cmd = scmnd;
1739
1740 memset(&cmd_request->vstor_packet, 0, sizeof(struct vstor_packet));
1741 vm_srb = &cmd_request->vstor_packet.vm_srb;
1742 vm_srb->time_out_value = 60;
1743
1744 vm_srb->srb_flags |=
1745 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1746
1747 if (scmnd->device->tagged_supported) {
1748 vm_srb->srb_flags |=
1749 (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
1750 vm_srb->queue_tag = SP_UNTAGGED;
1751 vm_srb->queue_action = SRB_SIMPLE_TAG_REQUEST;
1752 }
1753
1754 /* Build the SRB */
1755 switch (scmnd->sc_data_direction) {
1756 case DMA_TO_DEVICE:
1757 vm_srb->data_in = WRITE_TYPE;
1758 vm_srb->srb_flags |= SRB_FLAGS_DATA_OUT;
1759 break;
1760 case DMA_FROM_DEVICE:
1761 vm_srb->data_in = READ_TYPE;
1762 vm_srb->srb_flags |= SRB_FLAGS_DATA_IN;
1763 break;
1764 case DMA_NONE:
1765 vm_srb->data_in = UNKNOWN_TYPE;
1766 vm_srb->srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1767 break;
1768 default:
1769 /*
1770 * This is DMA_BIDIRECTIONAL or something else we are never
1771 * supposed to see here.
1772 */
1773 WARN(1, "Unexpected data direction: %d\n",
1774 scmnd->sc_data_direction);
1775 return -EINVAL;
1776 }
1777
1778
1779 vm_srb->port_number = host_dev->port;
1780 vm_srb->path_id = scmnd->device->channel;
1781 vm_srb->target_id = scmnd->device->id;
1782 vm_srb->lun = scmnd->device->lun;
1783
1784 vm_srb->cdb_length = scmnd->cmd_len;
1785
1786 memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1787
1788 sgl = (struct scatterlist *)scsi_sglist(scmnd);
1789
1790 length = scsi_bufflen(scmnd);
1791 payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1792 payload_sz = 0;
1793
1794 if (scsi_sg_count(scmnd)) {
1795 unsigned long offset_in_hvpg = offset_in_hvpage(sgl->offset);
1796 unsigned int hvpg_count = HVPFN_UP(offset_in_hvpg + length);
1797 struct scatterlist *sg;
1798 unsigned long hvpfn, hvpfns_to_add;
1799 int j, i = 0, sg_count;
1800
1801 payload_sz = (hvpg_count * sizeof(u64) +
1802 sizeof(struct vmbus_packet_mpb_array));
1803
1804 if (hvpg_count > MAX_PAGE_BUFFER_COUNT) {
1805 payload = kzalloc(payload_sz, GFP_ATOMIC);
1806 if (!payload)
1807 return SCSI_MLQUEUE_DEVICE_BUSY;
1808 }
1809
1810 payload->range.len = length;
1811 payload->range.offset = offset_in_hvpg;
1812
1813 sg_count = scsi_dma_map(scmnd);
1814 if (sg_count < 0) {
1815 ret = SCSI_MLQUEUE_DEVICE_BUSY;
1816 goto err_free_payload;
1817 }
1818
1819 for_each_sg(sgl, sg, sg_count, j) {
1820 /*
1821 * Init values for the current sgl entry. hvpfns_to_add
1822 * is in units of Hyper-V size pages. Handling the
1823 * PAGE_SIZE != HV_HYP_PAGE_SIZE case also handles
1824 * values of sgl->offset that are larger than PAGE_SIZE.
1825 * Such offsets are handled even on other than the first
1826 * sgl entry, provided they are a multiple of PAGE_SIZE.
1827 */
1828 hvpfn = HVPFN_DOWN(sg_dma_address(sg));
1829 hvpfns_to_add = HVPFN_UP(sg_dma_address(sg) +
1830 sg_dma_len(sg)) - hvpfn;
1831
1832 /*
1833 * Fill the next portion of the PFN array with
1834 * sequential Hyper-V PFNs for the continguous physical
1835 * memory described by the sgl entry. The end of the
1836 * last sgl should be reached at the same time that
1837 * the PFN array is filled.
1838 */
1839 while (hvpfns_to_add--)
1840 payload->range.pfn_array[i++] = hvpfn++;
1841 }
1842 }
1843
1844 cmd_request->payload = payload;
1845 cmd_request->payload_sz = payload_sz;
1846
1847 /* Invokes the vsc to start an IO */
1848 ret = storvsc_do_io(dev, cmd_request, get_cpu());
1849 put_cpu();
1850
1851 if (ret)
1852 scsi_dma_unmap(scmnd);
1853
1854 if (ret == -EAGAIN) {
1855 /* no more space */
1856 ret = SCSI_MLQUEUE_DEVICE_BUSY;
1857 goto err_free_payload;
1858 }
1859
1860 return 0;
1861
1862err_free_payload:
1863 if (payload_sz > sizeof(cmd_request->mpb))
1864 kfree(payload);
1865
1866 return ret;
1867}
1868
1869static struct scsi_host_template scsi_driver = {
1870 .module = THIS_MODULE,
1871 .name = "storvsc_host_t",
1872 .cmd_size = sizeof(struct storvsc_cmd_request),
1873 .bios_param = storvsc_get_chs,
1874 .queuecommand = storvsc_queuecommand,
1875 .eh_host_reset_handler = storvsc_host_reset_handler,
1876 .proc_name = "storvsc_host",
1877 .eh_timed_out = storvsc_eh_timed_out,
1878 .slave_alloc = storvsc_device_alloc,
1879 .slave_configure = storvsc_device_configure,
1880 .cmd_per_lun = 2048,
1881 .this_id = -1,
1882 /* Ensure there are no gaps in presented sgls */
1883 .virt_boundary_mask = HV_HYP_PAGE_SIZE - 1,
1884 .no_write_same = 1,
1885 .track_queue_depth = 1,
1886 .change_queue_depth = storvsc_change_queue_depth,
1887};
1888
1889enum {
1890 SCSI_GUID,
1891 IDE_GUID,
1892 SFC_GUID,
1893};
1894
1895static const struct hv_vmbus_device_id id_table[] = {
1896 /* SCSI guid */
1897 { HV_SCSI_GUID,
1898 .driver_data = SCSI_GUID
1899 },
1900 /* IDE guid */
1901 { HV_IDE_GUID,
1902 .driver_data = IDE_GUID
1903 },
1904 /* Fibre Channel GUID */
1905 {
1906 HV_SYNTHFC_GUID,
1907 .driver_data = SFC_GUID
1908 },
1909 { },
1910};
1911
1912MODULE_DEVICE_TABLE(vmbus, id_table);
1913
1914static const struct { guid_t guid; } fc_guid = { HV_SYNTHFC_GUID };
1915
1916static bool hv_dev_is_fc(struct hv_device *hv_dev)
1917{
1918 return guid_equal(&fc_guid.guid, &hv_dev->dev_type);
1919}
1920
1921static int storvsc_probe(struct hv_device *device,
1922 const struct hv_vmbus_device_id *dev_id)
1923{
1924 int ret;
1925 int num_cpus = num_online_cpus();
1926 int num_present_cpus = num_present_cpus();
1927 struct Scsi_Host *host;
1928 struct hv_host_device *host_dev;
1929 bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1930 bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
1931 int target = 0;
1932 struct storvsc_device *stor_device;
1933 int max_sub_channels = 0;
1934 u32 max_xfer_bytes;
1935
1936 /*
1937 * We support sub-channels for storage on SCSI and FC controllers.
1938 * The number of sub-channels offerred is based on the number of
1939 * VCPUs in the guest.
1940 */
1941 if (!dev_is_ide)
1942 max_sub_channels =
1943 (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
1944
1945 scsi_driver.can_queue = max_outstanding_req_per_channel *
1946 (max_sub_channels + 1) *
1947 (100 - ring_avail_percent_lowater) / 100;
1948
1949 host = scsi_host_alloc(&scsi_driver,
1950 sizeof(struct hv_host_device));
1951 if (!host)
1952 return -ENOMEM;
1953
1954 host_dev = shost_priv(host);
1955 memset(host_dev, 0, sizeof(struct hv_host_device));
1956
1957 host_dev->port = host->host_no;
1958 host_dev->dev = device;
1959 host_dev->host = host;
1960
1961
1962 stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
1963 if (!stor_device) {
1964 ret = -ENOMEM;
1965 goto err_out0;
1966 }
1967
1968 stor_device->destroy = false;
1969 init_waitqueue_head(&stor_device->waiting_to_drain);
1970 stor_device->device = device;
1971 stor_device->host = host;
1972 spin_lock_init(&stor_device->lock);
1973 hv_set_drvdata(device, stor_device);
1974 dma_set_min_align_mask(&device->device, HV_HYP_PAGE_SIZE - 1);
1975
1976 stor_device->port_number = host->host_no;
1977 ret = storvsc_connect_to_vsp(device, aligned_ringbuffer_size, is_fc);
1978 if (ret)
1979 goto err_out1;
1980
1981 host_dev->path = stor_device->path_id;
1982 host_dev->target = stor_device->target_id;
1983
1984 switch (dev_id->driver_data) {
1985 case SFC_GUID:
1986 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
1987 host->max_id = STORVSC_FC_MAX_TARGETS;
1988 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
1989#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1990 host->transportt = fc_transport_template;
1991#endif
1992 break;
1993
1994 case SCSI_GUID:
1995 host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
1996 host->max_id = STORVSC_MAX_TARGETS;
1997 host->max_channel = STORVSC_MAX_CHANNELS - 1;
1998 break;
1999
2000 default:
2001 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
2002 host->max_id = STORVSC_IDE_MAX_TARGETS;
2003 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
2004 break;
2005 }
2006 /* max cmd length */
2007 host->max_cmd_len = STORVSC_MAX_CMD_LEN;
2008 /*
2009 * Any reasonable Hyper-V configuration should provide
2010 * max_transfer_bytes value aligning to HV_HYP_PAGE_SIZE,
2011 * protecting it from any weird value.
2012 */
2013 max_xfer_bytes = round_down(stor_device->max_transfer_bytes, HV_HYP_PAGE_SIZE);
2014 if (is_fc)
2015 max_xfer_bytes = min(max_xfer_bytes, STORVSC_FC_MAX_XFER_SIZE);
2016
2017 /* max_hw_sectors_kb */
2018 host->max_sectors = max_xfer_bytes >> 9;
2019 /*
2020 * There are 2 requirements for Hyper-V storvsc sgl segments,
2021 * based on which the below calculation for max segments is
2022 * done:
2023 *
2024 * 1. Except for the first and last sgl segment, all sgl segments
2025 * should be align to HV_HYP_PAGE_SIZE, that also means the
2026 * maximum number of segments in a sgl can be calculated by
2027 * dividing the total max transfer length by HV_HYP_PAGE_SIZE.
2028 *
2029 * 2. Except for the first and last, each entry in the SGL must
2030 * have an offset that is a multiple of HV_HYP_PAGE_SIZE.
2031 */
2032 host->sg_tablesize = (max_xfer_bytes >> HV_HYP_PAGE_SHIFT) + 1;
2033 /*
2034 * For non-IDE disks, the host supports multiple channels.
2035 * Set the number of HW queues we are supporting.
2036 */
2037 if (!dev_is_ide) {
2038 if (storvsc_max_hw_queues > num_present_cpus) {
2039 storvsc_max_hw_queues = 0;
2040 storvsc_log(device, STORVSC_LOGGING_WARN,
2041 "Resetting invalid storvsc_max_hw_queues value to default.\n");
2042 }
2043 if (storvsc_max_hw_queues)
2044 host->nr_hw_queues = storvsc_max_hw_queues;
2045 else
2046 host->nr_hw_queues = num_present_cpus;
2047 }
2048
2049 /*
2050 * Set the error handler work queue.
2051 */
2052 host_dev->handle_error_wq =
2053 alloc_ordered_workqueue("storvsc_error_wq_%d",
2054 0,
2055 host->host_no);
2056 if (!host_dev->handle_error_wq) {
2057 ret = -ENOMEM;
2058 goto err_out2;
2059 }
2060 INIT_WORK(&host_dev->host_scan_work, storvsc_host_scan);
2061 /* Register the HBA and start the scsi bus scan */
2062 ret = scsi_add_host(host, &device->device);
2063 if (ret != 0)
2064 goto err_out3;
2065
2066 if (!dev_is_ide) {
2067 scsi_scan_host(host);
2068 } else {
2069 target = (device->dev_instance.b[5] << 8 |
2070 device->dev_instance.b[4]);
2071 ret = scsi_add_device(host, 0, target, 0);
2072 if (ret)
2073 goto err_out4;
2074 }
2075#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2076 if (host->transportt == fc_transport_template) {
2077 struct fc_rport_identifiers ids = {
2078 .roles = FC_PORT_ROLE_FCP_DUMMY_INITIATOR,
2079 };
2080
2081 fc_host_node_name(host) = stor_device->node_name;
2082 fc_host_port_name(host) = stor_device->port_name;
2083 stor_device->rport = fc_remote_port_add(host, 0, &ids);
2084 if (!stor_device->rport) {
2085 ret = -ENOMEM;
2086 goto err_out4;
2087 }
2088 }
2089#endif
2090 return 0;
2091
2092err_out4:
2093 scsi_remove_host(host);
2094
2095err_out3:
2096 destroy_workqueue(host_dev->handle_error_wq);
2097
2098err_out2:
2099 /*
2100 * Once we have connected with the host, we would need to
2101 * invoke storvsc_dev_remove() to rollback this state and
2102 * this call also frees up the stor_device; hence the jump around
2103 * err_out1 label.
2104 */
2105 storvsc_dev_remove(device);
2106 goto err_out0;
2107
2108err_out1:
2109 kfree(stor_device->stor_chns);
2110 kfree(stor_device);
2111
2112err_out0:
2113 scsi_host_put(host);
2114 return ret;
2115}
2116
2117/* Change a scsi target's queue depth */
2118static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth)
2119{
2120 if (queue_depth > scsi_driver.can_queue)
2121 queue_depth = scsi_driver.can_queue;
2122
2123 return scsi_change_queue_depth(sdev, queue_depth);
2124}
2125
2126static void storvsc_remove(struct hv_device *dev)
2127{
2128 struct storvsc_device *stor_device = hv_get_drvdata(dev);
2129 struct Scsi_Host *host = stor_device->host;
2130 struct hv_host_device *host_dev = shost_priv(host);
2131
2132#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2133 if (host->transportt == fc_transport_template) {
2134 fc_remote_port_delete(stor_device->rport);
2135 fc_remove_host(host);
2136 }
2137#endif
2138 destroy_workqueue(host_dev->handle_error_wq);
2139 scsi_remove_host(host);
2140 storvsc_dev_remove(dev);
2141 scsi_host_put(host);
2142}
2143
2144static int storvsc_suspend(struct hv_device *hv_dev)
2145{
2146 struct storvsc_device *stor_device = hv_get_drvdata(hv_dev);
2147 struct Scsi_Host *host = stor_device->host;
2148 struct hv_host_device *host_dev = shost_priv(host);
2149
2150 storvsc_wait_to_drain(stor_device);
2151
2152 drain_workqueue(host_dev->handle_error_wq);
2153
2154 vmbus_close(hv_dev->channel);
2155
2156 kfree(stor_device->stor_chns);
2157 stor_device->stor_chns = NULL;
2158
2159 cpumask_clear(&stor_device->alloced_cpus);
2160
2161 return 0;
2162}
2163
2164static int storvsc_resume(struct hv_device *hv_dev)
2165{
2166 int ret;
2167
2168 ret = storvsc_connect_to_vsp(hv_dev, aligned_ringbuffer_size,
2169 hv_dev_is_fc(hv_dev));
2170 return ret;
2171}
2172
2173static struct hv_driver storvsc_drv = {
2174 .name = KBUILD_MODNAME,
2175 .id_table = id_table,
2176 .probe = storvsc_probe,
2177 .remove = storvsc_remove,
2178 .suspend = storvsc_suspend,
2179 .resume = storvsc_resume,
2180 .driver = {
2181 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
2182 },
2183};
2184
2185#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2186static struct fc_function_template fc_transport_functions = {
2187 .show_host_node_name = 1,
2188 .show_host_port_name = 1,
2189};
2190#endif
2191
2192static int __init storvsc_drv_init(void)
2193{
2194 int ret;
2195
2196 /*
2197 * Divide the ring buffer data size (which is 1 page less
2198 * than the ring buffer size since that page is reserved for
2199 * the ring buffer indices) by the max request size (which is
2200 * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
2201 */
2202 aligned_ringbuffer_size = VMBUS_RING_SIZE(storvsc_ringbuffer_size);
2203 max_outstanding_req_per_channel =
2204 ((aligned_ringbuffer_size - PAGE_SIZE) /
2205 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
2206 sizeof(struct vstor_packet) + sizeof(u64),
2207 sizeof(u64)));
2208
2209#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2210 fc_transport_template = fc_attach_transport(&fc_transport_functions);
2211 if (!fc_transport_template)
2212 return -ENODEV;
2213#endif
2214
2215 ret = vmbus_driver_register(&storvsc_drv);
2216
2217#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2218 if (ret)
2219 fc_release_transport(fc_transport_template);
2220#endif
2221
2222 return ret;
2223}
2224
2225static void __exit storvsc_drv_exit(void)
2226{
2227 vmbus_driver_unregister(&storvsc_drv);
2228#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2229 fc_release_transport(fc_transport_template);
2230#endif
2231}
2232
2233MODULE_LICENSE("GPL");
2234MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
2235module_init(storvsc_drv_init);
2236module_exit(storvsc_drv_exit);