Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
152static bool hv_dev_is_fc(struct hv_device *hv_dev);
153
154#define STORVSC_LOGGING_NONE 0
155#define STORVSC_LOGGING_ERROR 1
156#define STORVSC_LOGGING_WARN 2
157
158static int logging_level = STORVSC_LOGGING_ERROR;
159module_param(logging_level, int, S_IRUGO|S_IWUSR);
160MODULE_PARM_DESC(logging_level,
161 "Logging level, 0 - None, 1 - Error (default), 2 - Warning.");
162
163static inline bool do_logging(int level)
164{
165 return logging_level >= level;
166}
167
168#define storvsc_log(dev, level, fmt, ...) \
169do { \
170 if (do_logging(level)) \
171 dev_warn(&(dev)->device, fmt, ##__VA_ARGS__); \
172} while (0)
173
174#define storvsc_log_ratelimited(dev, level, fmt, ...) \
175do { \
176 if (do_logging(level)) \
177 dev_warn_ratelimited(&(dev)->device, fmt, ##__VA_ARGS__); \
178} while (0)
179
180struct vmscsi_request {
181 u16 length;
182 u8 srb_status;
183 u8 scsi_status;
184
185 u8 port_number;
186 u8 path_id;
187 u8 target_id;
188 u8 lun;
189
190 u8 cdb_length;
191 u8 sense_info_length;
192 u8 data_in;
193 u8 reserved;
194
195 u32 data_transfer_length;
196
197 union {
198 u8 cdb[STORVSC_MAX_CMD_LEN];
199 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
200 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
201 };
202 /*
203 * The following was added in win8.
204 */
205 u16 reserve;
206 u8 queue_tag;
207 u8 queue_action;
208 u32 srb_flags;
209 u32 time_out_value;
210 u32 queue_sort_ey;
211
212} __attribute((packed));
213
214/*
215 * The list of windows version in order of preference.
216 */
217
218static const int protocol_version[] = {
219 VMSTOR_PROTO_VERSION_WIN10,
220 VMSTOR_PROTO_VERSION_WIN8_1,
221 VMSTOR_PROTO_VERSION_WIN8,
222};
223
224
225/*
226 * This structure is sent during the initialization phase to get the different
227 * properties of the channel.
228 */
229
230#define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL 0x1
231
232struct vmstorage_channel_properties {
233 u32 reserved;
234 u16 max_channel_cnt;
235 u16 reserved1;
236
237 u32 flags;
238 u32 max_transfer_bytes;
239
240 u64 reserved2;
241} __packed;
242
243/* This structure is sent during the storage protocol negotiations. */
244struct vmstorage_protocol_version {
245 /* Major (MSW) and minor (LSW) version numbers. */
246 u16 major_minor;
247
248 /*
249 * Revision number is auto-incremented whenever this file is changed
250 * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
251 * definitely indicate incompatibility--but it does indicate mismatched
252 * builds.
253 * This is only used on the windows side. Just set it to 0.
254 */
255 u16 revision;
256} __packed;
257
258/* Channel Property Flags */
259#define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
260#define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
261
262struct vstor_packet {
263 /* Requested operation type */
264 enum vstor_packet_operation operation;
265
266 /* Flags - see below for values */
267 u32 flags;
268
269 /* Status of the request returned from the server side. */
270 u32 status;
271
272 /* Data payload area */
273 union {
274 /*
275 * Structure used to forward SCSI commands from the
276 * client to the server.
277 */
278 struct vmscsi_request vm_srb;
279
280 /* Structure used to query channel properties. */
281 struct vmstorage_channel_properties storage_channel_properties;
282
283 /* Used during version negotiations. */
284 struct vmstorage_protocol_version version;
285
286 /* Fibre channel address packet */
287 struct hv_fc_wwn_packet wwn_packet;
288
289 /* Number of sub-channels to create */
290 u16 sub_channel_count;
291
292 /* This will be the maximum of the union members */
293 u8 buffer[0x34];
294 };
295} __packed;
296
297/*
298 * Packet Flags:
299 *
300 * This flag indicates that the server should send back a completion for this
301 * packet.
302 */
303
304#define REQUEST_COMPLETION_FLAG 0x1
305
306/* Matches Windows-end */
307enum storvsc_request_type {
308 WRITE_TYPE = 0,
309 READ_TYPE,
310 UNKNOWN_TYPE,
311};
312
313/*
314 * SRB status codes and masks. In the 8-bit field, the two high order bits
315 * are flags, while the remaining 6 bits are an integer status code. The
316 * definitions here include only the subset of the integer status codes that
317 * are tested for in this driver.
318 */
319#define SRB_STATUS_AUTOSENSE_VALID 0x80
320#define SRB_STATUS_QUEUE_FROZEN 0x40
321
322/* SRB status integer codes */
323#define SRB_STATUS_SUCCESS 0x01
324#define SRB_STATUS_ABORTED 0x02
325#define SRB_STATUS_ERROR 0x04
326#define SRB_STATUS_INVALID_REQUEST 0x06
327#define SRB_STATUS_TIMEOUT 0x09
328#define SRB_STATUS_SELECTION_TIMEOUT 0x0A
329#define SRB_STATUS_BUS_RESET 0x0E
330#define SRB_STATUS_DATA_OVERRUN 0x12
331#define SRB_STATUS_INVALID_LUN 0x20
332#define SRB_STATUS_INTERNAL_ERROR 0x30
333
334#define SRB_STATUS(status) \
335 (status & ~(SRB_STATUS_AUTOSENSE_VALID | SRB_STATUS_QUEUE_FROZEN))
336/*
337 * This is the end of Protocol specific defines.
338 */
339
340static int storvsc_ringbuffer_size = (128 * 1024);
341static int aligned_ringbuffer_size;
342static u32 max_outstanding_req_per_channel;
343static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth);
344
345static int storvsc_vcpus_per_sub_channel = 4;
346static unsigned int storvsc_max_hw_queues;
347
348module_param(storvsc_ringbuffer_size, int, S_IRUGO);
349MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
350
351module_param(storvsc_max_hw_queues, uint, 0644);
352MODULE_PARM_DESC(storvsc_max_hw_queues, "Maximum number of hardware queues");
353
354module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
355MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
356
357static int ring_avail_percent_lowater = 10;
358module_param(ring_avail_percent_lowater, int, S_IRUGO);
359MODULE_PARM_DESC(ring_avail_percent_lowater,
360 "Select a channel if available ring size > this in percent");
361
362/*
363 * Timeout in seconds for all devices managed by this driver.
364 */
365static const int storvsc_timeout = 180;
366
367#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
368static struct scsi_transport_template *fc_transport_template;
369#endif
370
371static struct scsi_host_template scsi_driver;
372static void storvsc_on_channel_callback(void *context);
373
374#define STORVSC_MAX_LUNS_PER_TARGET 255
375#define STORVSC_MAX_TARGETS 2
376#define STORVSC_MAX_CHANNELS 8
377
378#define STORVSC_FC_MAX_LUNS_PER_TARGET 255
379#define STORVSC_FC_MAX_TARGETS 128
380#define STORVSC_FC_MAX_CHANNELS 8
381#define STORVSC_FC_MAX_XFER_SIZE ((u32)(512 * 1024))
382
383#define STORVSC_IDE_MAX_LUNS_PER_TARGET 64
384#define STORVSC_IDE_MAX_TARGETS 1
385#define STORVSC_IDE_MAX_CHANNELS 1
386
387/*
388 * Upper bound on the size of a storvsc packet.
389 */
390#define STORVSC_MAX_PKT_SIZE (sizeof(struct vmpacket_descriptor) +\
391 sizeof(struct vstor_packet))
392
393struct storvsc_cmd_request {
394 struct scsi_cmnd *cmd;
395
396 struct hv_device *device;
397
398 /* Synchronize the request/response if needed */
399 struct completion wait_event;
400
401 struct vmbus_channel_packet_multipage_buffer mpb;
402 struct vmbus_packet_mpb_array *payload;
403 u32 payload_sz;
404
405 struct vstor_packet vstor_packet;
406};
407
408
409/* A storvsc device is a device object that contains a vmbus channel */
410struct storvsc_device {
411 struct hv_device *device;
412
413 bool destroy;
414 bool drain_notify;
415 atomic_t num_outstanding_req;
416 struct Scsi_Host *host;
417
418 wait_queue_head_t waiting_to_drain;
419
420 /*
421 * Each unique Port/Path/Target represents 1 channel ie scsi
422 * controller. In reality, the pathid, targetid is always 0
423 * and the port is set by us
424 */
425 unsigned int port_number;
426 unsigned char path_id;
427 unsigned char target_id;
428
429 /*
430 * Max I/O, the device can support.
431 */
432 u32 max_transfer_bytes;
433 /*
434 * Number of sub-channels we will open.
435 */
436 u16 num_sc;
437 struct vmbus_channel **stor_chns;
438 /*
439 * Mask of CPUs bound to subchannels.
440 */
441 struct cpumask alloced_cpus;
442 /*
443 * Serializes modifications of stor_chns[] from storvsc_do_io()
444 * and storvsc_change_target_cpu().
445 */
446 spinlock_t lock;
447 /* Used for vsc/vsp channel reset process */
448 struct storvsc_cmd_request init_request;
449 struct storvsc_cmd_request reset_request;
450 /*
451 * Currently active port and node names for FC devices.
452 */
453 u64 node_name;
454 u64 port_name;
455#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
456 struct fc_rport *rport;
457#endif
458};
459
460struct hv_host_device {
461 struct hv_device *dev;
462 unsigned int port;
463 unsigned char path;
464 unsigned char target;
465 struct workqueue_struct *handle_error_wq;
466 struct work_struct host_scan_work;
467 struct Scsi_Host *host;
468};
469
470struct storvsc_scan_work {
471 struct work_struct work;
472 struct Scsi_Host *host;
473 u8 lun;
474 u8 tgt_id;
475};
476
477static void storvsc_device_scan(struct work_struct *work)
478{
479 struct storvsc_scan_work *wrk;
480 struct scsi_device *sdev;
481
482 wrk = container_of(work, struct storvsc_scan_work, work);
483
484 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
485 if (!sdev)
486 goto done;
487 scsi_rescan_device(sdev);
488 scsi_device_put(sdev);
489
490done:
491 kfree(wrk);
492}
493
494static void storvsc_host_scan(struct work_struct *work)
495{
496 struct Scsi_Host *host;
497 struct scsi_device *sdev;
498 struct hv_host_device *host_device =
499 container_of(work, struct hv_host_device, host_scan_work);
500
501 host = host_device->host;
502 /*
503 * Before scanning the host, first check to see if any of the
504 * currently known devices have been hot removed. We issue a
505 * "unit ready" command against all currently known devices.
506 * This I/O will result in an error for devices that have been
507 * removed. As part of handling the I/O error, we remove the device.
508 *
509 * When a LUN is added or removed, the host sends us a signal to
510 * scan the host. Thus we are forced to discover the LUNs that
511 * may have been removed this way.
512 */
513 mutex_lock(&host->scan_mutex);
514 shost_for_each_device(sdev, host)
515 scsi_test_unit_ready(sdev, 1, 1, NULL);
516 mutex_unlock(&host->scan_mutex);
517 /*
518 * Now scan the host to discover LUNs that may have been added.
519 */
520 scsi_scan_host(host);
521}
522
523static void storvsc_remove_lun(struct work_struct *work)
524{
525 struct storvsc_scan_work *wrk;
526 struct scsi_device *sdev;
527
528 wrk = container_of(work, struct storvsc_scan_work, work);
529 if (!scsi_host_get(wrk->host))
530 goto done;
531
532 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
533
534 if (sdev) {
535 scsi_remove_device(sdev);
536 scsi_device_put(sdev);
537 }
538 scsi_host_put(wrk->host);
539
540done:
541 kfree(wrk);
542}
543
544
545/*
546 * We can get incoming messages from the host that are not in response to
547 * messages that we have sent out. An example of this would be messages
548 * received by the guest to notify dynamic addition/removal of LUNs. To
549 * deal with potential race conditions where the driver may be in the
550 * midst of being unloaded when we might receive an unsolicited message
551 * from the host, we have implemented a mechanism to gurantee sequential
552 * consistency:
553 *
554 * 1) Once the device is marked as being destroyed, we will fail all
555 * outgoing messages.
556 * 2) We permit incoming messages when the device is being destroyed,
557 * only to properly account for messages already sent out.
558 */
559
560static inline struct storvsc_device *get_out_stor_device(
561 struct hv_device *device)
562{
563 struct storvsc_device *stor_device;
564
565 stor_device = hv_get_drvdata(device);
566
567 if (stor_device && stor_device->destroy)
568 stor_device = NULL;
569
570 return stor_device;
571}
572
573
574static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
575{
576 dev->drain_notify = true;
577 wait_event(dev->waiting_to_drain,
578 atomic_read(&dev->num_outstanding_req) == 0);
579 dev->drain_notify = false;
580}
581
582static inline struct storvsc_device *get_in_stor_device(
583 struct hv_device *device)
584{
585 struct storvsc_device *stor_device;
586
587 stor_device = hv_get_drvdata(device);
588
589 if (!stor_device)
590 goto get_in_err;
591
592 /*
593 * If the device is being destroyed; allow incoming
594 * traffic only to cleanup outstanding requests.
595 */
596
597 if (stor_device->destroy &&
598 (atomic_read(&stor_device->num_outstanding_req) == 0))
599 stor_device = NULL;
600
601get_in_err:
602 return stor_device;
603
604}
605
606static void storvsc_change_target_cpu(struct vmbus_channel *channel, u32 old,
607 u32 new)
608{
609 struct storvsc_device *stor_device;
610 struct vmbus_channel *cur_chn;
611 bool old_is_alloced = false;
612 struct hv_device *device;
613 unsigned long flags;
614 int cpu;
615
616 device = channel->primary_channel ?
617 channel->primary_channel->device_obj
618 : channel->device_obj;
619 stor_device = get_out_stor_device(device);
620 if (!stor_device)
621 return;
622
623 /* See storvsc_do_io() -> get_og_chn(). */
624 spin_lock_irqsave(&stor_device->lock, flags);
625
626 /*
627 * Determines if the storvsc device has other channels assigned to
628 * the "old" CPU to update the alloced_cpus mask and the stor_chns
629 * array.
630 */
631 if (device->channel != channel && device->channel->target_cpu == old) {
632 cur_chn = device->channel;
633 old_is_alloced = true;
634 goto old_is_alloced;
635 }
636 list_for_each_entry(cur_chn, &device->channel->sc_list, sc_list) {
637 if (cur_chn == channel)
638 continue;
639 if (cur_chn->target_cpu == old) {
640 old_is_alloced = true;
641 goto old_is_alloced;
642 }
643 }
644
645old_is_alloced:
646 if (old_is_alloced)
647 WRITE_ONCE(stor_device->stor_chns[old], cur_chn);
648 else
649 cpumask_clear_cpu(old, &stor_device->alloced_cpus);
650
651 /* "Flush" the stor_chns array. */
652 for_each_possible_cpu(cpu) {
653 if (stor_device->stor_chns[cpu] && !cpumask_test_cpu(
654 cpu, &stor_device->alloced_cpus))
655 WRITE_ONCE(stor_device->stor_chns[cpu], NULL);
656 }
657
658 WRITE_ONCE(stor_device->stor_chns[new], channel);
659 cpumask_set_cpu(new, &stor_device->alloced_cpus);
660
661 spin_unlock_irqrestore(&stor_device->lock, flags);
662}
663
664static u64 storvsc_next_request_id(struct vmbus_channel *channel, u64 rqst_addr)
665{
666 struct storvsc_cmd_request *request =
667 (struct storvsc_cmd_request *)(unsigned long)rqst_addr;
668
669 if (rqst_addr == VMBUS_RQST_INIT)
670 return VMBUS_RQST_INIT;
671 if (rqst_addr == VMBUS_RQST_RESET)
672 return VMBUS_RQST_RESET;
673
674 /*
675 * Cannot return an ID of 0, which is reserved for an unsolicited
676 * message from Hyper-V.
677 */
678 return (u64)blk_mq_unique_tag(scsi_cmd_to_rq(request->cmd)) + 1;
679}
680
681static void handle_sc_creation(struct vmbus_channel *new_sc)
682{
683 struct hv_device *device = new_sc->primary_channel->device_obj;
684 struct device *dev = &device->device;
685 struct storvsc_device *stor_device;
686 struct vmstorage_channel_properties props;
687 int ret;
688
689 stor_device = get_out_stor_device(device);
690 if (!stor_device)
691 return;
692
693 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
694 new_sc->max_pkt_size = STORVSC_MAX_PKT_SIZE;
695
696 new_sc->next_request_id_callback = storvsc_next_request_id;
697
698 ret = vmbus_open(new_sc,
699 aligned_ringbuffer_size,
700 aligned_ringbuffer_size,
701 (void *)&props,
702 sizeof(struct vmstorage_channel_properties),
703 storvsc_on_channel_callback, new_sc);
704
705 /* In case vmbus_open() fails, we don't use the sub-channel. */
706 if (ret != 0) {
707 dev_err(dev, "Failed to open sub-channel: err=%d\n", ret);
708 return;
709 }
710
711 new_sc->change_target_cpu_callback = storvsc_change_target_cpu;
712
713 /* Add the sub-channel to the array of available channels. */
714 stor_device->stor_chns[new_sc->target_cpu] = new_sc;
715 cpumask_set_cpu(new_sc->target_cpu, &stor_device->alloced_cpus);
716}
717
718static void handle_multichannel_storage(struct hv_device *device, int max_chns)
719{
720 struct device *dev = &device->device;
721 struct storvsc_device *stor_device;
722 int num_sc;
723 struct storvsc_cmd_request *request;
724 struct vstor_packet *vstor_packet;
725 int ret, t;
726
727 /*
728 * If the number of CPUs is artificially restricted, such as
729 * with maxcpus=1 on the kernel boot line, Hyper-V could offer
730 * sub-channels >= the number of CPUs. These sub-channels
731 * should not be created. The primary channel is already created
732 * and assigned to one CPU, so check against # CPUs - 1.
733 */
734 num_sc = min((int)(num_online_cpus() - 1), max_chns);
735 if (!num_sc)
736 return;
737
738 stor_device = get_out_stor_device(device);
739 if (!stor_device)
740 return;
741
742 stor_device->num_sc = num_sc;
743 request = &stor_device->init_request;
744 vstor_packet = &request->vstor_packet;
745
746 /*
747 * Establish a handler for dealing with subchannels.
748 */
749 vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
750
751 /*
752 * Request the host to create sub-channels.
753 */
754 memset(request, 0, sizeof(struct storvsc_cmd_request));
755 init_completion(&request->wait_event);
756 vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
757 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
758 vstor_packet->sub_channel_count = num_sc;
759
760 ret = vmbus_sendpacket(device->channel, vstor_packet,
761 sizeof(struct vstor_packet),
762 VMBUS_RQST_INIT,
763 VM_PKT_DATA_INBAND,
764 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
765
766 if (ret != 0) {
767 dev_err(dev, "Failed to create sub-channel: err=%d\n", ret);
768 return;
769 }
770
771 t = wait_for_completion_timeout(&request->wait_event, storvsc_timeout * HZ);
772 if (t == 0) {
773 dev_err(dev, "Failed to create sub-channel: timed out\n");
774 return;
775 }
776
777 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
778 vstor_packet->status != 0) {
779 dev_err(dev, "Failed to create sub-channel: op=%d, host=0x%x\n",
780 vstor_packet->operation, vstor_packet->status);
781 return;
782 }
783
784 /*
785 * We need to do nothing here, because vmbus_process_offer()
786 * invokes channel->sc_creation_callback, which will open and use
787 * the sub-channel(s).
788 */
789}
790
791static void cache_wwn(struct storvsc_device *stor_device,
792 struct vstor_packet *vstor_packet)
793{
794 /*
795 * Cache the currently active port and node ww names.
796 */
797 if (vstor_packet->wwn_packet.primary_active) {
798 stor_device->node_name =
799 wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
800 stor_device->port_name =
801 wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
802 } else {
803 stor_device->node_name =
804 wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
805 stor_device->port_name =
806 wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
807 }
808}
809
810
811static int storvsc_execute_vstor_op(struct hv_device *device,
812 struct storvsc_cmd_request *request,
813 bool status_check)
814{
815 struct storvsc_device *stor_device;
816 struct vstor_packet *vstor_packet;
817 int ret, t;
818
819 stor_device = get_out_stor_device(device);
820 if (!stor_device)
821 return -ENODEV;
822
823 vstor_packet = &request->vstor_packet;
824
825 init_completion(&request->wait_event);
826 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
827
828 ret = vmbus_sendpacket(device->channel, vstor_packet,
829 sizeof(struct vstor_packet),
830 VMBUS_RQST_INIT,
831 VM_PKT_DATA_INBAND,
832 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
833 if (ret != 0)
834 return ret;
835
836 t = wait_for_completion_timeout(&request->wait_event, storvsc_timeout * HZ);
837 if (t == 0)
838 return -ETIMEDOUT;
839
840 if (!status_check)
841 return ret;
842
843 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
844 vstor_packet->status != 0)
845 return -EINVAL;
846
847 return ret;
848}
849
850static int storvsc_channel_init(struct hv_device *device, bool is_fc)
851{
852 struct storvsc_device *stor_device;
853 struct storvsc_cmd_request *request;
854 struct vstor_packet *vstor_packet;
855 int ret, i;
856 int max_chns;
857 bool process_sub_channels = false;
858
859 stor_device = get_out_stor_device(device);
860 if (!stor_device)
861 return -ENODEV;
862
863 request = &stor_device->init_request;
864 vstor_packet = &request->vstor_packet;
865
866 /*
867 * Now, initiate the vsc/vsp initialization protocol on the open
868 * channel
869 */
870 memset(request, 0, sizeof(struct storvsc_cmd_request));
871 vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
872 ret = storvsc_execute_vstor_op(device, request, true);
873 if (ret)
874 return ret;
875 /*
876 * Query host supported protocol version.
877 */
878
879 for (i = 0; i < ARRAY_SIZE(protocol_version); i++) {
880 /* reuse the packet for version range supported */
881 memset(vstor_packet, 0, sizeof(struct vstor_packet));
882 vstor_packet->operation =
883 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
884
885 vstor_packet->version.major_minor = protocol_version[i];
886
887 /*
888 * The revision number is only used in Windows; set it to 0.
889 */
890 vstor_packet->version.revision = 0;
891 ret = storvsc_execute_vstor_op(device, request, false);
892 if (ret != 0)
893 return ret;
894
895 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
896 return -EINVAL;
897
898 if (vstor_packet->status == 0) {
899 vmstor_proto_version = protocol_version[i];
900
901 break;
902 }
903 }
904
905 if (vstor_packet->status != 0) {
906 dev_err(&device->device, "Obsolete Hyper-V version\n");
907 return -EINVAL;
908 }
909
910
911 memset(vstor_packet, 0, sizeof(struct vstor_packet));
912 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
913 ret = storvsc_execute_vstor_op(device, request, true);
914 if (ret != 0)
915 return ret;
916
917 /*
918 * Check to see if multi-channel support is there.
919 * Hosts that implement protocol version of 5.1 and above
920 * support multi-channel.
921 */
922 max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
923
924 /*
925 * Allocate state to manage the sub-channels.
926 * We allocate an array based on the number of CPU ids. This array
927 * is initially sparsely populated for the CPUs assigned to channels:
928 * primary + sub-channels. As I/Os are initiated by different CPUs,
929 * the slots for all online CPUs are populated to evenly distribute
930 * the load across all channels.
931 */
932 stor_device->stor_chns = kcalloc(nr_cpu_ids, sizeof(void *),
933 GFP_KERNEL);
934 if (stor_device->stor_chns == NULL)
935 return -ENOMEM;
936
937 device->channel->change_target_cpu_callback = storvsc_change_target_cpu;
938
939 stor_device->stor_chns[device->channel->target_cpu] = device->channel;
940 cpumask_set_cpu(device->channel->target_cpu,
941 &stor_device->alloced_cpus);
942
943 if (vstor_packet->storage_channel_properties.flags &
944 STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
945 process_sub_channels = true;
946
947 stor_device->max_transfer_bytes =
948 vstor_packet->storage_channel_properties.max_transfer_bytes;
949
950 if (!is_fc)
951 goto done;
952
953 /*
954 * For FC devices retrieve FC HBA data.
955 */
956 memset(vstor_packet, 0, sizeof(struct vstor_packet));
957 vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
958 ret = storvsc_execute_vstor_op(device, request, true);
959 if (ret != 0)
960 return ret;
961
962 /*
963 * Cache the currently active port and node ww names.
964 */
965 cache_wwn(stor_device, vstor_packet);
966
967done:
968
969 memset(vstor_packet, 0, sizeof(struct vstor_packet));
970 vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
971 ret = storvsc_execute_vstor_op(device, request, true);
972 if (ret != 0)
973 return ret;
974
975 if (process_sub_channels)
976 handle_multichannel_storage(device, max_chns);
977
978 return ret;
979}
980
981static void storvsc_handle_error(struct vmscsi_request *vm_srb,
982 struct scsi_cmnd *scmnd,
983 struct Scsi_Host *host,
984 u8 asc, u8 ascq)
985{
986 struct storvsc_scan_work *wrk;
987 void (*process_err_fn)(struct work_struct *work);
988 struct hv_host_device *host_dev = shost_priv(host);
989
990 switch (SRB_STATUS(vm_srb->srb_status)) {
991 case SRB_STATUS_ERROR:
992 case SRB_STATUS_ABORTED:
993 case SRB_STATUS_INVALID_REQUEST:
994 case SRB_STATUS_INTERNAL_ERROR:
995 case SRB_STATUS_TIMEOUT:
996 case SRB_STATUS_SELECTION_TIMEOUT:
997 case SRB_STATUS_BUS_RESET:
998 case SRB_STATUS_DATA_OVERRUN:
999 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID) {
1000 /* Check for capacity change */
1001 if ((asc == 0x2a) && (ascq == 0x9)) {
1002 process_err_fn = storvsc_device_scan;
1003 /* Retry the I/O that triggered this. */
1004 set_host_byte(scmnd, DID_REQUEUE);
1005 goto do_work;
1006 }
1007
1008 /*
1009 * Check for "Operating parameters have changed"
1010 * due to Hyper-V changing the VHD/VHDX BlockSize
1011 * when adding/removing a differencing disk. This
1012 * causes discard_granularity to change, so do a
1013 * rescan to pick up the new granularity. We don't
1014 * want scsi_report_sense() to output a message
1015 * that a sysadmin wouldn't know what to do with.
1016 */
1017 if ((asc == 0x3f) && (ascq != 0x03) &&
1018 (ascq != 0x0e)) {
1019 process_err_fn = storvsc_device_scan;
1020 set_host_byte(scmnd, DID_REQUEUE);
1021 goto do_work;
1022 }
1023
1024 /*
1025 * Otherwise, let upper layer deal with the
1026 * error when sense message is present
1027 */
1028 return;
1029 }
1030
1031 /*
1032 * If there is an error; offline the device since all
1033 * error recovery strategies would have already been
1034 * deployed on the host side. However, if the command
1035 * were a pass-through command deal with it appropriately.
1036 */
1037 switch (scmnd->cmnd[0]) {
1038 case ATA_16:
1039 case ATA_12:
1040 set_host_byte(scmnd, DID_PASSTHROUGH);
1041 break;
1042 /*
1043 * On some Hyper-V hosts TEST_UNIT_READY command can
1044 * return SRB_STATUS_ERROR. Let the upper level code
1045 * deal with it based on the sense information.
1046 */
1047 case TEST_UNIT_READY:
1048 break;
1049 default:
1050 set_host_byte(scmnd, DID_ERROR);
1051 }
1052 return;
1053
1054 case SRB_STATUS_INVALID_LUN:
1055 set_host_byte(scmnd, DID_NO_CONNECT);
1056 process_err_fn = storvsc_remove_lun;
1057 goto do_work;
1058
1059 }
1060 return;
1061
1062do_work:
1063 /*
1064 * We need to schedule work to process this error; schedule it.
1065 */
1066 wrk = kmalloc_obj(struct storvsc_scan_work, GFP_ATOMIC);
1067 if (!wrk) {
1068 set_host_byte(scmnd, DID_BAD_TARGET);
1069 return;
1070 }
1071
1072 wrk->host = host;
1073 wrk->lun = vm_srb->lun;
1074 wrk->tgt_id = vm_srb->target_id;
1075 INIT_WORK(&wrk->work, process_err_fn);
1076 queue_work(host_dev->handle_error_wq, &wrk->work);
1077}
1078
1079
1080static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
1081 struct storvsc_device *stor_dev)
1082{
1083 struct scsi_cmnd *scmnd = cmd_request->cmd;
1084 struct scsi_sense_hdr sense_hdr;
1085 struct vmscsi_request *vm_srb;
1086 u32 data_transfer_length;
1087 struct Scsi_Host *host;
1088 u32 payload_sz = cmd_request->payload_sz;
1089 void *payload = cmd_request->payload;
1090 bool sense_ok;
1091
1092 host = stor_dev->host;
1093
1094 vm_srb = &cmd_request->vstor_packet.vm_srb;
1095 data_transfer_length = vm_srb->data_transfer_length;
1096
1097 scmnd->result = vm_srb->scsi_status;
1098
1099 if (scmnd->result) {
1100 sense_ok = scsi_normalize_sense(scmnd->sense_buffer,
1101 SCSI_SENSE_BUFFERSIZE, &sense_hdr);
1102
1103 if (sense_ok && do_logging(STORVSC_LOGGING_WARN))
1104 scsi_print_sense_hdr(scmnd->device, "storvsc",
1105 &sense_hdr);
1106 }
1107
1108 if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
1109 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
1110 sense_hdr.ascq);
1111 /*
1112 * The Windows driver set data_transfer_length on
1113 * SRB_STATUS_DATA_OVERRUN. On other errors, this value
1114 * is untouched. In these cases we set it to 0.
1115 */
1116 if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
1117 data_transfer_length = 0;
1118 }
1119
1120 /* Validate data_transfer_length (from Hyper-V) */
1121 if (data_transfer_length > cmd_request->payload->range.len)
1122 data_transfer_length = cmd_request->payload->range.len;
1123
1124 scsi_set_resid(scmnd,
1125 cmd_request->payload->range.len - data_transfer_length);
1126
1127 scsi_done(scmnd);
1128
1129 if (payload_sz >
1130 sizeof(struct vmbus_channel_packet_multipage_buffer))
1131 kfree(payload);
1132}
1133
1134/*
1135 * The current SCSI handling on the host side does not correctly handle:
1136 * INQUIRY with page code 0x80, MODE_SENSE / MODE_SENSE_10 with cmd[2] == 0x1c,
1137 * and (for FC) MAINTENANCE_IN / PERSISTENT_RESERVE_IN passthrough.
1138 */
1139static bool storvsc_host_mishandles_cmd(u8 opcode, struct hv_device *device)
1140{
1141 switch (opcode) {
1142 case INQUIRY:
1143 case MODE_SENSE:
1144 case MODE_SENSE_10:
1145 return true;
1146 case MAINTENANCE_IN:
1147 case PERSISTENT_RESERVE_IN:
1148 return hv_dev_is_fc(device);
1149 default:
1150 return false;
1151 }
1152}
1153
1154static void storvsc_on_io_completion(struct storvsc_device *stor_device,
1155 struct vstor_packet *vstor_packet,
1156 struct storvsc_cmd_request *request)
1157{
1158 struct vstor_packet *stor_pkt;
1159 struct hv_device *device = stor_device->device;
1160
1161 stor_pkt = &request->vstor_packet;
1162
1163 /*
1164 * Setup srb and scsi status so this won't be fatal.
1165 * We do this so we can distinguish truly fatal failues
1166 * (srb status == 0x4) and off-line the device in that case.
1167 */
1168
1169 if (storvsc_host_mishandles_cmd(stor_pkt->vm_srb.cdb[0], device)) {
1170 vstor_packet->vm_srb.scsi_status = 0;
1171 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1172 }
1173
1174 /* Copy over the status...etc */
1175 stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1176 stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1177
1178 /*
1179 * Copy over the sense_info_length, but limit to the known max
1180 * size if Hyper-V returns a bad value.
1181 */
1182 stor_pkt->vm_srb.sense_info_length = min_t(u8, STORVSC_SENSE_BUFFER_SIZE,
1183 vstor_packet->vm_srb.sense_info_length);
1184
1185 if (vstor_packet->vm_srb.scsi_status != 0 ||
1186 vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS) {
1187
1188 /*
1189 * Log TEST_UNIT_READY errors only as warnings. Hyper-V can
1190 * return errors when detecting devices using TEST_UNIT_READY,
1191 * and logging these as errors produces unhelpful noise.
1192 */
1193 int loglevel = (stor_pkt->vm_srb.cdb[0] == TEST_UNIT_READY) ?
1194 STORVSC_LOGGING_WARN : STORVSC_LOGGING_ERROR;
1195
1196 storvsc_log_ratelimited(device, loglevel,
1197 "tag#%d cmd 0x%x status: scsi 0x%x srb 0x%x host 0x%x\n",
1198 scsi_cmd_to_rq(request->cmd)->tag,
1199 stor_pkt->vm_srb.cdb[0],
1200 vstor_packet->vm_srb.scsi_status,
1201 vstor_packet->vm_srb.srb_status,
1202 vstor_packet->status);
1203 }
1204
1205 if (vstor_packet->vm_srb.scsi_status == SAM_STAT_CHECK_CONDITION &&
1206 (vstor_packet->vm_srb.srb_status & SRB_STATUS_AUTOSENSE_VALID))
1207 memcpy(request->cmd->sense_buffer,
1208 vstor_packet->vm_srb.sense_data,
1209 stor_pkt->vm_srb.sense_info_length);
1210
1211 stor_pkt->vm_srb.data_transfer_length =
1212 vstor_packet->vm_srb.data_transfer_length;
1213
1214 storvsc_command_completion(request, stor_device);
1215
1216 if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1217 stor_device->drain_notify)
1218 wake_up(&stor_device->waiting_to_drain);
1219}
1220
1221static void storvsc_on_receive(struct storvsc_device *stor_device,
1222 struct vstor_packet *vstor_packet,
1223 struct storvsc_cmd_request *request)
1224{
1225 struct hv_host_device *host_dev;
1226 switch (vstor_packet->operation) {
1227 case VSTOR_OPERATION_COMPLETE_IO:
1228 storvsc_on_io_completion(stor_device, vstor_packet, request);
1229 break;
1230
1231 case VSTOR_OPERATION_REMOVE_DEVICE:
1232 case VSTOR_OPERATION_ENUMERATE_BUS:
1233 host_dev = shost_priv(stor_device->host);
1234 queue_work(
1235 host_dev->handle_error_wq, &host_dev->host_scan_work);
1236 break;
1237
1238 case VSTOR_OPERATION_FCHBA_DATA:
1239 cache_wwn(stor_device, vstor_packet);
1240#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1241 fc_host_node_name(stor_device->host) = stor_device->node_name;
1242 fc_host_port_name(stor_device->host) = stor_device->port_name;
1243#endif
1244 break;
1245 default:
1246 break;
1247 }
1248}
1249
1250static void storvsc_on_channel_callback(void *context)
1251{
1252 struct vmbus_channel *channel = (struct vmbus_channel *)context;
1253 const struct vmpacket_descriptor *desc;
1254 struct hv_device *device;
1255 struct storvsc_device *stor_device;
1256 struct Scsi_Host *shost;
1257 unsigned long time_limit = jiffies + msecs_to_jiffies(CALLBACK_TIMEOUT);
1258
1259 if (channel->primary_channel != NULL)
1260 device = channel->primary_channel->device_obj;
1261 else
1262 device = channel->device_obj;
1263
1264 stor_device = get_in_stor_device(device);
1265 if (!stor_device)
1266 return;
1267
1268 shost = stor_device->host;
1269
1270 foreach_vmbus_pkt(desc, channel) {
1271 struct vstor_packet *packet = hv_pkt_data(desc);
1272 struct storvsc_cmd_request *request = NULL;
1273 u32 pktlen = hv_pkt_datalen(desc);
1274 u64 rqst_id = desc->trans_id;
1275 u32 minlen = rqst_id ? sizeof(struct vstor_packet) :
1276 sizeof(enum vstor_packet_operation);
1277
1278 if (unlikely(time_after(jiffies, time_limit))) {
1279 hv_pkt_iter_close(channel);
1280 return;
1281 }
1282
1283 if (pktlen < minlen) {
1284 dev_err(&device->device,
1285 "Invalid pkt: id=%llu, len=%u, minlen=%u\n",
1286 rqst_id, pktlen, minlen);
1287 continue;
1288 }
1289
1290 if (rqst_id == VMBUS_RQST_INIT) {
1291 request = &stor_device->init_request;
1292 } else if (rqst_id == VMBUS_RQST_RESET) {
1293 request = &stor_device->reset_request;
1294 } else {
1295 /* Hyper-V can send an unsolicited message with ID of 0 */
1296 if (rqst_id == 0) {
1297 /*
1298 * storvsc_on_receive() looks at the vstor_packet in the message
1299 * from the ring buffer.
1300 *
1301 * - If the operation in the vstor_packet is COMPLETE_IO, then
1302 * we call storvsc_on_io_completion(), and dereference the
1303 * guest memory address. Make sure we don't call
1304 * storvsc_on_io_completion() with a guest memory address
1305 * that is zero if Hyper-V were to construct and send such
1306 * a bogus packet.
1307 *
1308 * - If the operation in the vstor_packet is FCHBA_DATA, then
1309 * we call cache_wwn(), and access the data payload area of
1310 * the packet (wwn_packet); however, there is no guarantee
1311 * that the packet is big enough to contain such area.
1312 * Future-proof the code by rejecting such a bogus packet.
1313 */
1314 if (packet->operation == VSTOR_OPERATION_COMPLETE_IO ||
1315 packet->operation == VSTOR_OPERATION_FCHBA_DATA) {
1316 dev_err(&device->device, "Invalid packet with ID of 0\n");
1317 continue;
1318 }
1319 } else {
1320 struct scsi_cmnd *scmnd;
1321
1322 /* Transaction 'rqst_id' corresponds to tag 'rqst_id - 1' */
1323 scmnd = scsi_host_find_tag(shost, rqst_id - 1);
1324 if (scmnd == NULL) {
1325 dev_err(&device->device, "Incorrect transaction ID\n");
1326 continue;
1327 }
1328 request = (struct storvsc_cmd_request *)scsi_cmd_priv(scmnd);
1329 scsi_dma_unmap(scmnd);
1330 }
1331
1332 storvsc_on_receive(stor_device, packet, request);
1333 continue;
1334 }
1335
1336 memcpy(&request->vstor_packet, packet,
1337 sizeof(struct vstor_packet));
1338 complete(&request->wait_event);
1339 }
1340}
1341
1342static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
1343 bool is_fc)
1344{
1345 struct vmstorage_channel_properties props;
1346 int ret;
1347
1348 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1349
1350 device->channel->max_pkt_size = STORVSC_MAX_PKT_SIZE;
1351 device->channel->next_request_id_callback = storvsc_next_request_id;
1352
1353 ret = vmbus_open(device->channel,
1354 ring_size,
1355 ring_size,
1356 (void *)&props,
1357 sizeof(struct vmstorage_channel_properties),
1358 storvsc_on_channel_callback, device->channel);
1359
1360 if (ret != 0)
1361 return ret;
1362
1363 ret = storvsc_channel_init(device, is_fc);
1364 if (ret)
1365 vmbus_close(device->channel);
1366
1367 return ret;
1368}
1369
1370static int storvsc_dev_remove(struct hv_device *device)
1371{
1372 struct storvsc_device *stor_device;
1373
1374 stor_device = hv_get_drvdata(device);
1375
1376 stor_device->destroy = true;
1377
1378 /* Make sure flag is set before waiting */
1379 wmb();
1380
1381 /*
1382 * At this point, all outbound traffic should be disable. We
1383 * only allow inbound traffic (responses) to proceed so that
1384 * outstanding requests can be completed.
1385 */
1386
1387 storvsc_wait_to_drain(stor_device);
1388
1389 /*
1390 * Since we have already drained, we don't need to busy wait
1391 * as was done in final_release_stor_device()
1392 * Note that we cannot set the ext pointer to NULL until
1393 * we have drained - to drain the outgoing packets, we need to
1394 * allow incoming packets.
1395 */
1396 hv_set_drvdata(device, NULL);
1397
1398 /* Close the channel */
1399 vmbus_close(device->channel);
1400
1401 kfree(stor_device->stor_chns);
1402 kfree(stor_device);
1403 return 0;
1404}
1405
1406static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device,
1407 u16 q_num)
1408{
1409 u16 slot = 0;
1410 u16 hash_qnum;
1411 const struct cpumask *node_mask;
1412 int num_channels, tgt_cpu;
1413
1414 if (stor_device->num_sc == 0) {
1415 stor_device->stor_chns[q_num] = stor_device->device->channel;
1416 return stor_device->device->channel;
1417 }
1418
1419 /*
1420 * Our channel array could be sparsley populated and we
1421 * initiated I/O on a processor/hw-q that does not
1422 * currently have a designated channel. Fix this.
1423 * The strategy is simple:
1424 * I. Prefer the channel associated with the current CPU
1425 * II. Ensure NUMA locality
1426 * III. Distribute evenly (best effort)
1427 */
1428
1429 /* Prefer the channel on the I/O issuing processor/hw-q */
1430 if (cpumask_test_cpu(q_num, &stor_device->alloced_cpus))
1431 return stor_device->stor_chns[q_num];
1432
1433 node_mask = cpumask_of_node(cpu_to_node(q_num));
1434
1435 num_channels = 0;
1436 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1437 if (cpumask_test_cpu(tgt_cpu, node_mask))
1438 num_channels++;
1439 }
1440 if (num_channels == 0) {
1441 stor_device->stor_chns[q_num] = stor_device->device->channel;
1442 return stor_device->device->channel;
1443 }
1444
1445 hash_qnum = q_num;
1446 while (hash_qnum >= num_channels)
1447 hash_qnum -= num_channels;
1448
1449 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1450 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1451 continue;
1452 if (slot == hash_qnum)
1453 break;
1454 slot++;
1455 }
1456
1457 stor_device->stor_chns[q_num] = stor_device->stor_chns[tgt_cpu];
1458
1459 return stor_device->stor_chns[q_num];
1460}
1461
1462
1463static int storvsc_do_io(struct hv_device *device,
1464 struct storvsc_cmd_request *request, u16 q_num)
1465{
1466 struct storvsc_device *stor_device;
1467 struct vstor_packet *vstor_packet;
1468 struct vmbus_channel *outgoing_channel, *channel;
1469 unsigned long flags;
1470 int ret = 0;
1471 const struct cpumask *node_mask;
1472 int tgt_cpu;
1473
1474 vstor_packet = &request->vstor_packet;
1475 stor_device = get_out_stor_device(device);
1476
1477 if (!stor_device)
1478 return -ENODEV;
1479
1480
1481 request->device = device;
1482 /*
1483 * Select an appropriate channel to send the request out.
1484 */
1485 /* See storvsc_change_target_cpu(). */
1486 outgoing_channel = READ_ONCE(stor_device->stor_chns[q_num]);
1487 if (outgoing_channel != NULL) {
1488 if (hv_get_avail_to_write_percent(&outgoing_channel->outbound)
1489 > ring_avail_percent_lowater)
1490 goto found_channel;
1491
1492 /*
1493 * Channel is busy, try to find a channel on the same NUMA node
1494 */
1495 node_mask = cpumask_of_node(cpu_to_node(q_num));
1496 for_each_cpu_wrap(tgt_cpu, &stor_device->alloced_cpus,
1497 q_num + 1) {
1498 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1499 continue;
1500 channel = READ_ONCE(stor_device->stor_chns[tgt_cpu]);
1501 if (!channel)
1502 continue;
1503 if (hv_get_avail_to_write_percent(&channel->outbound)
1504 > ring_avail_percent_lowater) {
1505 outgoing_channel = channel;
1506 goto found_channel;
1507 }
1508 }
1509
1510 /*
1511 * If we reach here, all the channels on the current
1512 * NUMA node are busy. Try to find a channel in
1513 * all NUMA nodes
1514 */
1515 for_each_cpu_wrap(tgt_cpu, &stor_device->alloced_cpus,
1516 q_num + 1) {
1517 channel = READ_ONCE(stor_device->stor_chns[tgt_cpu]);
1518 if (!channel)
1519 continue;
1520 if (hv_get_avail_to_write_percent(&channel->outbound)
1521 > ring_avail_percent_lowater) {
1522 outgoing_channel = channel;
1523 goto found_channel;
1524 }
1525 }
1526 /*
1527 * If we reach here, all the channels are busy. Use the
1528 * original channel found.
1529 */
1530 } else {
1531 spin_lock_irqsave(&stor_device->lock, flags);
1532 outgoing_channel = stor_device->stor_chns[q_num];
1533 if (outgoing_channel != NULL) {
1534 spin_unlock_irqrestore(&stor_device->lock, flags);
1535 goto found_channel;
1536 }
1537 outgoing_channel = get_og_chn(stor_device, q_num);
1538 spin_unlock_irqrestore(&stor_device->lock, flags);
1539 }
1540
1541found_channel:
1542 vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1543
1544 vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
1545
1546
1547 vstor_packet->vm_srb.sense_info_length = STORVSC_SENSE_BUFFER_SIZE;
1548
1549
1550 vstor_packet->vm_srb.data_transfer_length =
1551 request->payload->range.len;
1552
1553 vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1554
1555 if (request->payload->range.len) {
1556
1557 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1558 request->payload, request->payload_sz,
1559 vstor_packet,
1560 sizeof(struct vstor_packet),
1561 (unsigned long)request);
1562 } else {
1563 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1564 sizeof(struct vstor_packet),
1565 (unsigned long)request,
1566 VM_PKT_DATA_INBAND,
1567 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1568 }
1569
1570 if (ret != 0)
1571 return ret;
1572
1573 atomic_inc(&stor_device->num_outstanding_req);
1574
1575 return ret;
1576}
1577
1578static int storvsc_device_alloc(struct scsi_device *sdevice)
1579{
1580 /*
1581 * Set blist flag to permit the reading of the VPD pages even when
1582 * the target may claim SPC-2 compliance. MSFT targets currently
1583 * claim SPC-2 compliance while they implement post SPC-2 features.
1584 * With this flag we can correctly handle WRITE_SAME_16 issues.
1585 *
1586 * Hypervisor reports SCSI_UNKNOWN type for DVD ROM device but
1587 * still supports REPORT LUN.
1588 */
1589 sdevice->sdev_bflags = BLIST_REPORTLUN2 | BLIST_TRY_VPD_PAGES;
1590
1591 return 0;
1592}
1593
1594static int storvsc_sdev_configure(struct scsi_device *sdevice,
1595 struct queue_limits *lim)
1596{
1597 blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1598
1599 /* storvsc devices don't support MAINTENANCE_IN SCSI cmd */
1600 sdevice->no_report_opcodes = 1;
1601 sdevice->no_write_same = 1;
1602
1603 /*
1604 * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1605 * if the device is a MSFT virtual device. If the host is
1606 * WIN10 or newer, allow write_same.
1607 */
1608 if (!strncmp(sdevice->vendor, "Msft", 4)) {
1609 switch (vmstor_proto_version) {
1610 case VMSTOR_PROTO_VERSION_WIN8:
1611 case VMSTOR_PROTO_VERSION_WIN8_1:
1612 sdevice->scsi_level = SCSI_SPC_3;
1613 break;
1614 }
1615
1616 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1617 sdevice->no_write_same = 0;
1618 }
1619
1620 return 0;
1621}
1622
1623static int storvsc_get_chs(struct scsi_device *sdev, struct gendisk *unused,
1624 sector_t capacity, int *info)
1625{
1626 sector_t nsect = capacity;
1627 sector_t cylinders = nsect;
1628 int heads, sectors_pt;
1629
1630 /*
1631 * We are making up these values; let us keep it simple.
1632 */
1633 heads = 0xff;
1634 sectors_pt = 0x3f; /* Sectors per track */
1635 sector_div(cylinders, heads * sectors_pt);
1636 if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1637 cylinders = 0xffff;
1638
1639 info[0] = heads;
1640 info[1] = sectors_pt;
1641 info[2] = (int)cylinders;
1642
1643 return 0;
1644}
1645
1646static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1647{
1648 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1649 struct hv_device *device = host_dev->dev;
1650
1651 struct storvsc_device *stor_device;
1652 struct storvsc_cmd_request *request;
1653 struct vstor_packet *vstor_packet;
1654 int ret, t;
1655
1656 stor_device = get_out_stor_device(device);
1657 if (!stor_device)
1658 return FAILED;
1659
1660 request = &stor_device->reset_request;
1661 vstor_packet = &request->vstor_packet;
1662 memset(vstor_packet, 0, sizeof(struct vstor_packet));
1663
1664 init_completion(&request->wait_event);
1665
1666 vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1667 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1668 vstor_packet->vm_srb.path_id = stor_device->path_id;
1669
1670 ret = vmbus_sendpacket(device->channel, vstor_packet,
1671 sizeof(struct vstor_packet),
1672 VMBUS_RQST_RESET,
1673 VM_PKT_DATA_INBAND,
1674 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1675 if (ret != 0)
1676 return FAILED;
1677
1678 t = wait_for_completion_timeout(&request->wait_event, storvsc_timeout * HZ);
1679 if (t == 0)
1680 return TIMEOUT_ERROR;
1681
1682
1683 /*
1684 * At this point, all outstanding requests in the adapter
1685 * should have been flushed out and return to us
1686 * There is a potential race here where the host may be in
1687 * the process of responding when we return from here.
1688 * Just wait for all in-transit packets to be accounted for
1689 * before we return from here.
1690 */
1691 storvsc_wait_to_drain(stor_device);
1692
1693 return SUCCESS;
1694}
1695
1696/*
1697 * The host guarantees to respond to each command, although I/O latencies might
1698 * be unbounded on Azure. Reset the timer unconditionally to give the host a
1699 * chance to perform EH.
1700 */
1701static enum scsi_timeout_action storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1702{
1703 return SCSI_EH_RESET_TIMER;
1704}
1705
1706static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1707{
1708 bool allowed = true;
1709 u8 scsi_op = scmnd->cmnd[0];
1710
1711 switch (scsi_op) {
1712 /* the host does not handle WRITE_SAME, log accident usage */
1713 case WRITE_SAME:
1714 /*
1715 * smartd sends this command and the host does not handle
1716 * this. So, don't send it.
1717 */
1718 case SET_WINDOW:
1719 set_host_byte(scmnd, DID_ERROR);
1720 allowed = false;
1721 break;
1722 default:
1723 break;
1724 }
1725 return allowed;
1726}
1727
1728static enum scsi_qc_status storvsc_queuecommand(struct Scsi_Host *host,
1729 struct scsi_cmnd *scmnd)
1730{
1731 int ret;
1732 struct hv_host_device *host_dev = shost_priv(host);
1733 struct hv_device *dev = host_dev->dev;
1734 struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1735 struct scatterlist *sgl;
1736 struct vmscsi_request *vm_srb;
1737 struct vmbus_packet_mpb_array *payload;
1738 u32 payload_sz;
1739 u32 length;
1740
1741 if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1742 /*
1743 * On legacy hosts filter unimplemented commands.
1744 * Future hosts are expected to correctly handle
1745 * unsupported commands. Furthermore, it is
1746 * possible that some of the currently
1747 * unsupported commands maybe supported in
1748 * future versions of the host.
1749 */
1750 if (!storvsc_scsi_cmd_ok(scmnd)) {
1751 scsi_done(scmnd);
1752 return 0;
1753 }
1754 }
1755
1756 /* Setup the cmd request */
1757 cmd_request->cmd = scmnd;
1758
1759 memset(&cmd_request->vstor_packet, 0, sizeof(struct vstor_packet));
1760 vm_srb = &cmd_request->vstor_packet.vm_srb;
1761 vm_srb->time_out_value = 60;
1762
1763 vm_srb->srb_flags |=
1764 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1765
1766 if (scmnd->device->tagged_supported) {
1767 vm_srb->srb_flags |=
1768 (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
1769 vm_srb->queue_tag = SP_UNTAGGED;
1770 vm_srb->queue_action = SRB_SIMPLE_TAG_REQUEST;
1771 }
1772
1773 /* Build the SRB */
1774 switch (scmnd->sc_data_direction) {
1775 case DMA_TO_DEVICE:
1776 vm_srb->data_in = WRITE_TYPE;
1777 vm_srb->srb_flags |= SRB_FLAGS_DATA_OUT;
1778 break;
1779 case DMA_FROM_DEVICE:
1780 vm_srb->data_in = READ_TYPE;
1781 vm_srb->srb_flags |= SRB_FLAGS_DATA_IN;
1782 break;
1783 case DMA_NONE:
1784 vm_srb->data_in = UNKNOWN_TYPE;
1785 vm_srb->srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1786 break;
1787 default:
1788 /*
1789 * This is DMA_BIDIRECTIONAL or something else we are never
1790 * supposed to see here.
1791 */
1792 WARN(1, "Unexpected data direction: %d\n",
1793 scmnd->sc_data_direction);
1794 return -EINVAL;
1795 }
1796
1797
1798 vm_srb->port_number = host_dev->port;
1799 vm_srb->path_id = scmnd->device->channel;
1800 vm_srb->target_id = scmnd->device->id;
1801 vm_srb->lun = scmnd->device->lun;
1802
1803 vm_srb->cdb_length = scmnd->cmd_len;
1804
1805 memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1806
1807 sgl = (struct scatterlist *)scsi_sglist(scmnd);
1808
1809 length = scsi_bufflen(scmnd);
1810 payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1811 payload->range.len = 0;
1812 payload_sz = 0;
1813
1814 if (scsi_sg_count(scmnd)) {
1815 unsigned long offset_in_hvpg = offset_in_hvpage(sgl->offset);
1816 unsigned int hvpg_count = HVPFN_UP(offset_in_hvpg + length);
1817 struct scatterlist *sg;
1818 unsigned long hvpfn, hvpfns_to_add;
1819 int j, i = 0, sg_count;
1820
1821 payload_sz = (hvpg_count * sizeof(u64) +
1822 sizeof(struct vmbus_packet_mpb_array));
1823
1824 if (hvpg_count > MAX_PAGE_BUFFER_COUNT) {
1825 payload = kzalloc(payload_sz, GFP_ATOMIC);
1826 if (!payload)
1827 return SCSI_MLQUEUE_DEVICE_BUSY;
1828 }
1829
1830 payload->rangecount = 1;
1831 payload->range.len = length;
1832 payload->range.offset = offset_in_hvpg;
1833
1834 sg_count = scsi_dma_map(scmnd);
1835 if (sg_count < 0) {
1836 ret = SCSI_MLQUEUE_DEVICE_BUSY;
1837 goto err_free_payload;
1838 }
1839
1840 for_each_sg(sgl, sg, sg_count, j) {
1841 /*
1842 * Init values for the current sgl entry. hvpfns_to_add
1843 * is in units of Hyper-V size pages. Handling the
1844 * PAGE_SIZE != HV_HYP_PAGE_SIZE case also handles
1845 * values of sgl->offset that are larger than PAGE_SIZE.
1846 * Such offsets are handled even on other than the first
1847 * sgl entry, provided they are a multiple of PAGE_SIZE.
1848 */
1849 hvpfn = HVPFN_DOWN(sg_dma_address(sg));
1850 hvpfns_to_add = HVPFN_UP(sg_dma_address(sg) +
1851 sg_dma_len(sg)) - hvpfn;
1852
1853 /*
1854 * Fill the next portion of the PFN array with
1855 * sequential Hyper-V PFNs for the continguous physical
1856 * memory described by the sgl entry. The end of the
1857 * last sgl should be reached at the same time that
1858 * the PFN array is filled.
1859 */
1860 while (hvpfns_to_add--)
1861 payload->range.pfn_array[i++] = hvpfn++;
1862 }
1863 }
1864
1865 cmd_request->payload = payload;
1866 cmd_request->payload_sz = payload_sz;
1867
1868 /* Invokes the vsc to start an IO */
1869 migrate_disable();
1870 ret = storvsc_do_io(dev, cmd_request, smp_processor_id());
1871 migrate_enable();
1872
1873 if (ret)
1874 scsi_dma_unmap(scmnd);
1875
1876 if (ret == -EAGAIN) {
1877 /* no more space */
1878 ret = SCSI_MLQUEUE_DEVICE_BUSY;
1879 goto err_free_payload;
1880 }
1881
1882 return 0;
1883
1884err_free_payload:
1885 if (payload_sz > sizeof(cmd_request->mpb))
1886 kfree(payload);
1887
1888 return ret;
1889}
1890
1891static struct scsi_host_template scsi_driver = {
1892 .module = THIS_MODULE,
1893 .name = "storvsc_host_t",
1894 .cmd_size = sizeof(struct storvsc_cmd_request),
1895 .bios_param = storvsc_get_chs,
1896 .queuecommand = storvsc_queuecommand,
1897 .eh_host_reset_handler = storvsc_host_reset_handler,
1898 .proc_name = "storvsc_host",
1899 .eh_timed_out = storvsc_eh_timed_out,
1900 .sdev_init = storvsc_device_alloc,
1901 .sdev_configure = storvsc_sdev_configure,
1902 .cmd_per_lun = 2048,
1903 .this_id = -1,
1904 /* Ensure there are no gaps in presented sgls */
1905 .virt_boundary_mask = HV_HYP_PAGE_SIZE - 1,
1906 .no_write_same = 1,
1907 .track_queue_depth = 1,
1908 .change_queue_depth = storvsc_change_queue_depth,
1909};
1910
1911enum {
1912 SCSI_GUID,
1913 IDE_GUID,
1914 SFC_GUID,
1915};
1916
1917static const struct hv_vmbus_device_id id_table[] = {
1918 /* SCSI guid */
1919 { HV_SCSI_GUID,
1920 .driver_data = SCSI_GUID
1921 },
1922 /* IDE guid */
1923 { HV_IDE_GUID,
1924 .driver_data = IDE_GUID
1925 },
1926 /* Fibre Channel GUID */
1927 {
1928 HV_SYNTHFC_GUID,
1929 .driver_data = SFC_GUID
1930 },
1931 { },
1932};
1933
1934MODULE_DEVICE_TABLE(vmbus, id_table);
1935
1936static const struct { guid_t guid; } fc_guid = { HV_SYNTHFC_GUID };
1937
1938static bool hv_dev_is_fc(struct hv_device *hv_dev)
1939{
1940 return guid_equal(&fc_guid.guid, &hv_dev->dev_type);
1941}
1942
1943static int storvsc_probe(struct hv_device *device,
1944 const struct hv_vmbus_device_id *dev_id)
1945{
1946 int ret;
1947 int num_cpus = num_online_cpus();
1948 int num_present_cpus = num_present_cpus();
1949 struct Scsi_Host *host;
1950 struct hv_host_device *host_dev;
1951 bool dev_is_ide = dev_id->driver_data == IDE_GUID;
1952 bool is_fc = dev_id->driver_data == SFC_GUID;
1953 int target = 0;
1954 struct storvsc_device *stor_device;
1955 int max_sub_channels = 0;
1956 u32 max_xfer_bytes;
1957
1958 /*
1959 * We support sub-channels for storage on SCSI and FC controllers.
1960 * The number of sub-channels offerred is based on the number of
1961 * VCPUs in the guest.
1962 */
1963 if (!dev_is_ide)
1964 max_sub_channels =
1965 (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
1966
1967 scsi_driver.can_queue = max_outstanding_req_per_channel *
1968 (max_sub_channels + 1) *
1969 (100 - ring_avail_percent_lowater) / 100;
1970
1971 host = scsi_host_alloc(&scsi_driver,
1972 sizeof(struct hv_host_device));
1973 if (!host)
1974 return -ENOMEM;
1975
1976 host_dev = shost_priv(host);
1977 memset(host_dev, 0, sizeof(struct hv_host_device));
1978
1979 host_dev->port = host->host_no;
1980 host_dev->dev = device;
1981 host_dev->host = host;
1982
1983
1984 stor_device = kzalloc_obj(struct storvsc_device);
1985 if (!stor_device) {
1986 ret = -ENOMEM;
1987 goto err_out0;
1988 }
1989
1990 stor_device->destroy = false;
1991 init_waitqueue_head(&stor_device->waiting_to_drain);
1992 stor_device->device = device;
1993 stor_device->host = host;
1994 spin_lock_init(&stor_device->lock);
1995 hv_set_drvdata(device, stor_device);
1996 dma_set_min_align_mask(&device->device, HV_HYP_PAGE_SIZE - 1);
1997
1998 stor_device->port_number = host->host_no;
1999 ret = storvsc_connect_to_vsp(device, aligned_ringbuffer_size, is_fc);
2000 if (ret)
2001 goto err_out1;
2002
2003 host_dev->path = stor_device->path_id;
2004 host_dev->target = stor_device->target_id;
2005
2006 switch (dev_id->driver_data) {
2007 case SFC_GUID:
2008 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
2009 host->max_id = STORVSC_FC_MAX_TARGETS;
2010 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
2011#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2012 host->transportt = fc_transport_template;
2013#endif
2014 break;
2015
2016 case SCSI_GUID:
2017 host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
2018 host->max_id = STORVSC_MAX_TARGETS;
2019 host->max_channel = STORVSC_MAX_CHANNELS - 1;
2020 break;
2021
2022 default:
2023 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
2024 host->max_id = STORVSC_IDE_MAX_TARGETS;
2025 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
2026 break;
2027 }
2028 /* max cmd length */
2029 host->max_cmd_len = STORVSC_MAX_CMD_LEN;
2030 /*
2031 * Any reasonable Hyper-V configuration should provide
2032 * max_transfer_bytes value aligning to HV_HYP_PAGE_SIZE,
2033 * protecting it from any weird value.
2034 */
2035 max_xfer_bytes = round_down(stor_device->max_transfer_bytes, HV_HYP_PAGE_SIZE);
2036 if (is_fc)
2037 max_xfer_bytes = min(max_xfer_bytes, STORVSC_FC_MAX_XFER_SIZE);
2038
2039 /* max_hw_sectors_kb */
2040 host->max_sectors = max_xfer_bytes >> 9;
2041 /*
2042 * There are 2 requirements for Hyper-V storvsc sgl segments,
2043 * based on which the below calculation for max segments is
2044 * done:
2045 *
2046 * 1. Except for the first and last sgl segment, all sgl segments
2047 * should be align to HV_HYP_PAGE_SIZE, that also means the
2048 * maximum number of segments in a sgl can be calculated by
2049 * dividing the total max transfer length by HV_HYP_PAGE_SIZE.
2050 *
2051 * 2. Except for the first and last, each entry in the SGL must
2052 * have an offset that is a multiple of HV_HYP_PAGE_SIZE.
2053 */
2054 host->sg_tablesize = (max_xfer_bytes >> HV_HYP_PAGE_SHIFT) + 1;
2055 /*
2056 * For non-IDE disks, the host supports multiple channels.
2057 * Set the number of HW queues we are supporting.
2058 */
2059 if (!dev_is_ide) {
2060 if (storvsc_max_hw_queues > num_present_cpus) {
2061 storvsc_max_hw_queues = 0;
2062 storvsc_log(device, STORVSC_LOGGING_WARN,
2063 "Resetting invalid storvsc_max_hw_queues value to default.\n");
2064 }
2065 if (storvsc_max_hw_queues)
2066 host->nr_hw_queues = storvsc_max_hw_queues;
2067 else
2068 host->nr_hw_queues = num_present_cpus;
2069 }
2070
2071 /*
2072 * Set the error handler work queue.
2073 */
2074 host_dev->handle_error_wq =
2075 alloc_ordered_workqueue("storvsc_error_wq_%d",
2076 0,
2077 host->host_no);
2078 if (!host_dev->handle_error_wq) {
2079 ret = -ENOMEM;
2080 goto err_out2;
2081 }
2082 INIT_WORK(&host_dev->host_scan_work, storvsc_host_scan);
2083 /* Register the HBA and start the scsi bus scan */
2084 ret = scsi_add_host(host, &device->device);
2085 if (ret != 0)
2086 goto err_out3;
2087
2088 if (!dev_is_ide) {
2089 scsi_scan_host(host);
2090 } else {
2091 target = (device->dev_instance.b[5] << 8 |
2092 device->dev_instance.b[4]);
2093 ret = scsi_add_device(host, 0, target, 0);
2094 if (ret)
2095 goto err_out4;
2096 }
2097#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2098 if (host->transportt == fc_transport_template) {
2099 struct fc_rport_identifiers ids = {
2100 .roles = FC_PORT_ROLE_FCP_DUMMY_INITIATOR,
2101 };
2102
2103 fc_host_node_name(host) = stor_device->node_name;
2104 fc_host_port_name(host) = stor_device->port_name;
2105 stor_device->rport = fc_remote_port_add(host, 0, &ids);
2106 if (!stor_device->rport) {
2107 ret = -ENOMEM;
2108 goto err_out4;
2109 }
2110 }
2111#endif
2112 return 0;
2113
2114err_out4:
2115 scsi_remove_host(host);
2116
2117err_out3:
2118 destroy_workqueue(host_dev->handle_error_wq);
2119
2120err_out2:
2121 /*
2122 * Once we have connected with the host, we would need to
2123 * invoke storvsc_dev_remove() to rollback this state and
2124 * this call also frees up the stor_device; hence the jump around
2125 * err_out1 label.
2126 */
2127 storvsc_dev_remove(device);
2128 goto err_out0;
2129
2130err_out1:
2131 kfree(stor_device->stor_chns);
2132 kfree(stor_device);
2133
2134err_out0:
2135 scsi_host_put(host);
2136 return ret;
2137}
2138
2139/* Change a scsi target's queue depth */
2140static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth)
2141{
2142 if (queue_depth > scsi_driver.can_queue)
2143 queue_depth = scsi_driver.can_queue;
2144
2145 return scsi_change_queue_depth(sdev, queue_depth);
2146}
2147
2148static void storvsc_remove(struct hv_device *dev)
2149{
2150 struct storvsc_device *stor_device = hv_get_drvdata(dev);
2151 struct Scsi_Host *host = stor_device->host;
2152 struct hv_host_device *host_dev = shost_priv(host);
2153
2154#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2155 if (host->transportt == fc_transport_template) {
2156 fc_remote_port_delete(stor_device->rport);
2157 fc_remove_host(host);
2158 }
2159#endif
2160 destroy_workqueue(host_dev->handle_error_wq);
2161 scsi_remove_host(host);
2162 storvsc_dev_remove(dev);
2163 scsi_host_put(host);
2164}
2165
2166static int storvsc_suspend(struct hv_device *hv_dev)
2167{
2168 struct storvsc_device *stor_device = hv_get_drvdata(hv_dev);
2169 struct Scsi_Host *host = stor_device->host;
2170 struct hv_host_device *host_dev = shost_priv(host);
2171
2172 storvsc_wait_to_drain(stor_device);
2173
2174 drain_workqueue(host_dev->handle_error_wq);
2175
2176 vmbus_close(hv_dev->channel);
2177
2178 kfree(stor_device->stor_chns);
2179 stor_device->stor_chns = NULL;
2180
2181 cpumask_clear(&stor_device->alloced_cpus);
2182
2183 return 0;
2184}
2185
2186static int storvsc_resume(struct hv_device *hv_dev)
2187{
2188 int ret;
2189
2190 ret = storvsc_connect_to_vsp(hv_dev, aligned_ringbuffer_size,
2191 hv_dev_is_fc(hv_dev));
2192 return ret;
2193}
2194
2195static struct hv_driver storvsc_drv = {
2196 .name = KBUILD_MODNAME,
2197 .id_table = id_table,
2198 .probe = storvsc_probe,
2199 .remove = storvsc_remove,
2200 .suspend = storvsc_suspend,
2201 .resume = storvsc_resume,
2202 .driver = {
2203 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
2204 },
2205};
2206
2207#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2208static struct fc_function_template fc_transport_functions = {
2209 .show_host_node_name = 1,
2210 .show_host_port_name = 1,
2211};
2212#endif
2213
2214static int __init storvsc_drv_init(void)
2215{
2216 int ret;
2217
2218 /*
2219 * Divide the ring buffer data size (which is 1 page less
2220 * than the ring buffer size since that page is reserved for
2221 * the ring buffer indices) by the max request size (which is
2222 * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
2223 */
2224 aligned_ringbuffer_size = VMBUS_RING_SIZE(storvsc_ringbuffer_size);
2225 max_outstanding_req_per_channel =
2226 ((aligned_ringbuffer_size - PAGE_SIZE) /
2227 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
2228 sizeof(struct vstor_packet) + sizeof(u64),
2229 sizeof(u64)));
2230
2231#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2232 fc_transport_template = fc_attach_transport(&fc_transport_functions);
2233 if (!fc_transport_template)
2234 return -ENODEV;
2235#endif
2236
2237 ret = vmbus_driver_register(&storvsc_drv);
2238
2239#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2240 if (ret)
2241 fc_release_transport(fc_transport_template);
2242#endif
2243
2244 return ret;
2245}
2246
2247static void __exit storvsc_drv_exit(void)
2248{
2249 vmbus_driver_unregister(&storvsc_drv);
2250#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
2251 fc_release_transport(fc_transport_template);
2252#endif
2253}
2254
2255MODULE_LICENSE("GPL");
2256MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
2257module_init(storvsc_drv_init);
2258module_exit(storvsc_drv_exit);