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storvsc_drv.c
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storvsc_drv.c
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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2009, Microsoft Corporation.
*
* Authors:
* Haiyang Zhang <haiyangz@microsoft.com>
* Hank Janssen <hjanssen@microsoft.com>
* K. Y. Srinivasan <kys@microsoft.com>
*/
#include <linux/kernel.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/completion.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/hyperv.h>
#include <linux/blkdev.h>
#include <linux/dma-mapping.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_devinfo.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_transport_fc.h>
#include <scsi/scsi_transport.h>
/*
* All wire protocol details (storage protocol between the guest and the host)
* are consolidated here.
*
* Begin protocol definitions.
*/
/*
* Version history:
* V1 Beta: 0.1
* V1 RC < 2008/1/31: 1.0
* V1 RC > 2008/1/31: 2.0
* Win7: 4.2
* Win8: 5.1
* Win8.1: 6.0
* Win10: 6.2
*/
#define VMSTOR_PROTO_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
(((MINOR_) & 0xff)))
#define VMSTOR_PROTO_VERSION_WIN6 VMSTOR_PROTO_VERSION(2, 0)
#define VMSTOR_PROTO_VERSION_WIN7 VMSTOR_PROTO_VERSION(4, 2)
#define VMSTOR_PROTO_VERSION_WIN8 VMSTOR_PROTO_VERSION(5, 1)
#define VMSTOR_PROTO_VERSION_WIN8_1 VMSTOR_PROTO_VERSION(6, 0)
#define VMSTOR_PROTO_VERSION_WIN10 VMSTOR_PROTO_VERSION(6, 2)
/* channel callback timeout in ms */
#define CALLBACK_TIMEOUT 2
/* Packet structure describing virtual storage requests. */
enum vstor_packet_operation {
VSTOR_OPERATION_COMPLETE_IO = 1,
VSTOR_OPERATION_REMOVE_DEVICE = 2,
VSTOR_OPERATION_EXECUTE_SRB = 3,
VSTOR_OPERATION_RESET_LUN = 4,
VSTOR_OPERATION_RESET_ADAPTER = 5,
VSTOR_OPERATION_RESET_BUS = 6,
VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
VSTOR_OPERATION_END_INITIALIZATION = 8,
VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
VSTOR_OPERATION_QUERY_PROPERTIES = 10,
VSTOR_OPERATION_ENUMERATE_BUS = 11,
VSTOR_OPERATION_FCHBA_DATA = 12,
VSTOR_OPERATION_CREATE_SUB_CHANNELS = 13,
VSTOR_OPERATION_MAXIMUM = 13
};
/*
* WWN packet for Fibre Channel HBA
*/
struct hv_fc_wwn_packet {
u8 primary_active;
u8 reserved1[3];
u8 primary_port_wwn[8];
u8 primary_node_wwn[8];
u8 secondary_port_wwn[8];
u8 secondary_node_wwn[8];
};
/*
* SRB Flag Bits
*/
#define SRB_FLAGS_QUEUE_ACTION_ENABLE 0x00000002
#define SRB_FLAGS_DISABLE_DISCONNECT 0x00000004
#define SRB_FLAGS_DISABLE_SYNCH_TRANSFER 0x00000008
#define SRB_FLAGS_BYPASS_FROZEN_QUEUE 0x00000010
#define SRB_FLAGS_DISABLE_AUTOSENSE 0x00000020
#define SRB_FLAGS_DATA_IN 0x00000040
#define SRB_FLAGS_DATA_OUT 0x00000080
#define SRB_FLAGS_NO_DATA_TRANSFER 0x00000000
#define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT)
#define SRB_FLAGS_NO_QUEUE_FREEZE 0x00000100
#define SRB_FLAGS_ADAPTER_CACHE_ENABLE 0x00000200
#define SRB_FLAGS_FREE_SENSE_BUFFER 0x00000400
/*
* This flag indicates the request is part of the workflow for processing a D3.
*/
#define SRB_FLAGS_D3_PROCESSING 0x00000800
#define SRB_FLAGS_IS_ACTIVE 0x00010000
#define SRB_FLAGS_ALLOCATED_FROM_ZONE 0x00020000
#define SRB_FLAGS_SGLIST_FROM_POOL 0x00040000
#define SRB_FLAGS_BYPASS_LOCKED_QUEUE 0x00080000
#define SRB_FLAGS_NO_KEEP_AWAKE 0x00100000
#define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE 0x00200000
#define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT 0x00400000
#define SRB_FLAGS_DONT_START_NEXT_PACKET 0x00800000
#define SRB_FLAGS_PORT_DRIVER_RESERVED 0x0F000000
#define SRB_FLAGS_CLASS_DRIVER_RESERVED 0xF0000000
#define SP_UNTAGGED ((unsigned char) ~0)
#define SRB_SIMPLE_TAG_REQUEST 0x20
/*
* Platform neutral description of a scsi request -
* this remains the same across the write regardless of 32/64 bit
* note: it's patterned off the SCSI_PASS_THROUGH structure
*/
#define STORVSC_MAX_CMD_LEN 0x10
/* Sense buffer size is the same for all versions since Windows 8 */
#define STORVSC_SENSE_BUFFER_SIZE 0x14
#define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14
/*
* The storage protocol version is determined during the
* initial exchange with the host. It will indicate which
* storage functionality is available in the host.
*/
static int vmstor_proto_version;
#define STORVSC_LOGGING_NONE 0
#define STORVSC_LOGGING_ERROR 1
#define STORVSC_LOGGING_WARN 2
static int logging_level = STORVSC_LOGGING_ERROR;
module_param(logging_level, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(logging_level,
"Logging level, 0 - None, 1 - Error (default), 2 - Warning.");
static inline bool do_logging(int level)
{
return logging_level >= level;
}
#define storvsc_log(dev, level, fmt, ...) \
do { \
if (do_logging(level)) \
dev_warn(&(dev)->device, fmt, ##__VA_ARGS__); \
} while (0)
struct vmscsi_request {
u16 length;
u8 srb_status;
u8 scsi_status;
u8 port_number;
u8 path_id;
u8 target_id;
u8 lun;
u8 cdb_length;
u8 sense_info_length;
u8 data_in;
u8 reserved;
u32 data_transfer_length;
union {
u8 cdb[STORVSC_MAX_CMD_LEN];
u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
};
/*
* The following was added in win8.
*/
u16 reserve;
u8 queue_tag;
u8 queue_action;
u32 srb_flags;
u32 time_out_value;
u32 queue_sort_ey;
} __attribute((packed));
/*
* The list of windows version in order of preference.
*/
static const int protocol_version[] = {
VMSTOR_PROTO_VERSION_WIN10,
VMSTOR_PROTO_VERSION_WIN8_1,
VMSTOR_PROTO_VERSION_WIN8,
};
/*
* This structure is sent during the initialization phase to get the different
* properties of the channel.
*/
#define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL 0x1
struct vmstorage_channel_properties {
u32 reserved;
u16 max_channel_cnt;
u16 reserved1;
u32 flags;
u32 max_transfer_bytes;
u64 reserved2;
} __packed;
/* This structure is sent during the storage protocol negotiations. */
struct vmstorage_protocol_version {
/* Major (MSW) and minor (LSW) version numbers. */
u16 major_minor;
/*
* Revision number is auto-incremented whenever this file is changed
* (See FILL_VMSTOR_REVISION macro above). Mismatch does not
* definitely indicate incompatibility--but it does indicate mismatched
* builds.
* This is only used on the windows side. Just set it to 0.
*/
u16 revision;
} __packed;
/* Channel Property Flags */
#define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
#define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
struct vstor_packet {
/* Requested operation type */
enum vstor_packet_operation operation;
/* Flags - see below for values */
u32 flags;
/* Status of the request returned from the server side. */
u32 status;
/* Data payload area */
union {
/*
* Structure used to forward SCSI commands from the
* client to the server.
*/
struct vmscsi_request vm_srb;
/* Structure used to query channel properties. */
struct vmstorage_channel_properties storage_channel_properties;
/* Used during version negotiations. */
struct vmstorage_protocol_version version;
/* Fibre channel address packet */
struct hv_fc_wwn_packet wwn_packet;
/* Number of sub-channels to create */
u16 sub_channel_count;
/* This will be the maximum of the union members */
u8 buffer[0x34];
};
} __packed;
/*
* Packet Flags:
*
* This flag indicates that the server should send back a completion for this
* packet.
*/
#define REQUEST_COMPLETION_FLAG 0x1
/* Matches Windows-end */
enum storvsc_request_type {
WRITE_TYPE = 0,
READ_TYPE,
UNKNOWN_TYPE,
};
/*
* SRB status codes and masks. In the 8-bit field, the two high order bits
* are flags, while the remaining 6 bits are an integer status code. The
* definitions here include only the subset of the integer status codes that
* are tested for in this driver.
*/
#define SRB_STATUS_AUTOSENSE_VALID 0x80
#define SRB_STATUS_QUEUE_FROZEN 0x40
/* SRB status integer codes */
#define SRB_STATUS_SUCCESS 0x01
#define SRB_STATUS_ABORTED 0x02
#define SRB_STATUS_ERROR 0x04
#define SRB_STATUS_INVALID_REQUEST 0x06
#define SRB_STATUS_DATA_OVERRUN 0x12
#define SRB_STATUS_INVALID_LUN 0x20
#define SRB_STATUS(status) \
(status & ~(SRB_STATUS_AUTOSENSE_VALID | SRB_STATUS_QUEUE_FROZEN))
/*
* This is the end of Protocol specific defines.
*/
static int storvsc_ringbuffer_size = (128 * 1024);
static u32 max_outstanding_req_per_channel;
static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth);
static int storvsc_vcpus_per_sub_channel = 4;
static unsigned int storvsc_max_hw_queues;
module_param(storvsc_ringbuffer_size, int, S_IRUGO);
MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
module_param(storvsc_max_hw_queues, uint, 0644);
MODULE_PARM_DESC(storvsc_max_hw_queues, "Maximum number of hardware queues");
module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
static int ring_avail_percent_lowater = 10;
module_param(ring_avail_percent_lowater, int, S_IRUGO);
MODULE_PARM_DESC(ring_avail_percent_lowater,
"Select a channel if available ring size > this in percent");
/*
* Timeout in seconds for all devices managed by this driver.
*/
static int storvsc_timeout = 180;
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
static struct scsi_transport_template *fc_transport_template;
#endif
static struct scsi_host_template scsi_driver;
static void storvsc_on_channel_callback(void *context);
#define STORVSC_MAX_LUNS_PER_TARGET 255
#define STORVSC_MAX_TARGETS 2
#define STORVSC_MAX_CHANNELS 8
#define STORVSC_FC_MAX_LUNS_PER_TARGET 255
#define STORVSC_FC_MAX_TARGETS 128
#define STORVSC_FC_MAX_CHANNELS 8
#define STORVSC_FC_MAX_XFER_SIZE ((u32)(512 * 1024))
#define STORVSC_IDE_MAX_LUNS_PER_TARGET 64
#define STORVSC_IDE_MAX_TARGETS 1
#define STORVSC_IDE_MAX_CHANNELS 1
/*
* Upper bound on the size of a storvsc packet.
*/
#define STORVSC_MAX_PKT_SIZE (sizeof(struct vmpacket_descriptor) +\
sizeof(struct vstor_packet))
struct storvsc_cmd_request {
struct scsi_cmnd *cmd;
struct hv_device *device;
/* Synchronize the request/response if needed */
struct completion wait_event;
struct vmbus_channel_packet_multipage_buffer mpb;
struct vmbus_packet_mpb_array *payload;
u32 payload_sz;
struct vstor_packet vstor_packet;
};
/* A storvsc device is a device object that contains a vmbus channel */
struct storvsc_device {
struct hv_device *device;
bool destroy;
bool drain_notify;
atomic_t num_outstanding_req;
struct Scsi_Host *host;
wait_queue_head_t waiting_to_drain;
/*
* Each unique Port/Path/Target represents 1 channel ie scsi
* controller. In reality, the pathid, targetid is always 0
* and the port is set by us
*/
unsigned int port_number;
unsigned char path_id;
unsigned char target_id;
/*
* Max I/O, the device can support.
*/
u32 max_transfer_bytes;
/*
* Number of sub-channels we will open.
*/
u16 num_sc;
struct vmbus_channel **stor_chns;
/*
* Mask of CPUs bound to subchannels.
*/
struct cpumask alloced_cpus;
/*
* Serializes modifications of stor_chns[] from storvsc_do_io()
* and storvsc_change_target_cpu().
*/
spinlock_t lock;
/* Used for vsc/vsp channel reset process */
struct storvsc_cmd_request init_request;
struct storvsc_cmd_request reset_request;
/*
* Currently active port and node names for FC devices.
*/
u64 node_name;
u64 port_name;
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
struct fc_rport *rport;
#endif
};
struct hv_host_device {
struct hv_device *dev;
unsigned int port;
unsigned char path;
unsigned char target;
struct workqueue_struct *handle_error_wq;
struct work_struct host_scan_work;
struct Scsi_Host *host;
};
struct storvsc_scan_work {
struct work_struct work;
struct Scsi_Host *host;
u8 lun;
u8 tgt_id;
};
static void storvsc_device_scan(struct work_struct *work)
{
struct storvsc_scan_work *wrk;
struct scsi_device *sdev;
wrk = container_of(work, struct storvsc_scan_work, work);
sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
if (!sdev)
goto done;
scsi_rescan_device(&sdev->sdev_gendev);
scsi_device_put(sdev);
done:
kfree(wrk);
}
static void storvsc_host_scan(struct work_struct *work)
{
struct Scsi_Host *host;
struct scsi_device *sdev;
struct hv_host_device *host_device =
container_of(work, struct hv_host_device, host_scan_work);
host = host_device->host;
/*
* Before scanning the host, first check to see if any of the
* currently known devices have been hot removed. We issue a
* "unit ready" command against all currently known devices.
* This I/O will result in an error for devices that have been
* removed. As part of handling the I/O error, we remove the device.
*
* When a LUN is added or removed, the host sends us a signal to
* scan the host. Thus we are forced to discover the LUNs that
* may have been removed this way.
*/
mutex_lock(&host->scan_mutex);
shost_for_each_device(sdev, host)
scsi_test_unit_ready(sdev, 1, 1, NULL);
mutex_unlock(&host->scan_mutex);
/*
* Now scan the host to discover LUNs that may have been added.
*/
scsi_scan_host(host);
}
static void storvsc_remove_lun(struct work_struct *work)
{
struct storvsc_scan_work *wrk;
struct scsi_device *sdev;
wrk = container_of(work, struct storvsc_scan_work, work);
if (!scsi_host_get(wrk->host))
goto done;
sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
if (sdev) {
scsi_remove_device(sdev);
scsi_device_put(sdev);
}
scsi_host_put(wrk->host);
done:
kfree(wrk);
}
/*
* We can get incoming messages from the host that are not in response to
* messages that we have sent out. An example of this would be messages
* received by the guest to notify dynamic addition/removal of LUNs. To
* deal with potential race conditions where the driver may be in the
* midst of being unloaded when we might receive an unsolicited message
* from the host, we have implemented a mechanism to gurantee sequential
* consistency:
*
* 1) Once the device is marked as being destroyed, we will fail all
* outgoing messages.
* 2) We permit incoming messages when the device is being destroyed,
* only to properly account for messages already sent out.
*/
static inline struct storvsc_device *get_out_stor_device(
struct hv_device *device)
{
struct storvsc_device *stor_device;
stor_device = hv_get_drvdata(device);
if (stor_device && stor_device->destroy)
stor_device = NULL;
return stor_device;
}
static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
{
dev->drain_notify = true;
wait_event(dev->waiting_to_drain,
atomic_read(&dev->num_outstanding_req) == 0);
dev->drain_notify = false;
}
static inline struct storvsc_device *get_in_stor_device(
struct hv_device *device)
{
struct storvsc_device *stor_device;
stor_device = hv_get_drvdata(device);
if (!stor_device)
goto get_in_err;
/*
* If the device is being destroyed; allow incoming
* traffic only to cleanup outstanding requests.
*/
if (stor_device->destroy &&
(atomic_read(&stor_device->num_outstanding_req) == 0))
stor_device = NULL;
get_in_err:
return stor_device;
}
static void storvsc_change_target_cpu(struct vmbus_channel *channel, u32 old,
u32 new)
{
struct storvsc_device *stor_device;
struct vmbus_channel *cur_chn;
bool old_is_alloced = false;
struct hv_device *device;
unsigned long flags;
int cpu;
device = channel->primary_channel ?
channel->primary_channel->device_obj
: channel->device_obj;
stor_device = get_out_stor_device(device);
if (!stor_device)
return;
/* See storvsc_do_io() -> get_og_chn(). */
spin_lock_irqsave(&stor_device->lock, flags);
/*
* Determines if the storvsc device has other channels assigned to
* the "old" CPU to update the alloced_cpus mask and the stor_chns
* array.
*/
if (device->channel != channel && device->channel->target_cpu == old) {
cur_chn = device->channel;
old_is_alloced = true;
goto old_is_alloced;
}
list_for_each_entry(cur_chn, &device->channel->sc_list, sc_list) {
if (cur_chn == channel)
continue;
if (cur_chn->target_cpu == old) {
old_is_alloced = true;
goto old_is_alloced;
}
}
old_is_alloced:
if (old_is_alloced)
WRITE_ONCE(stor_device->stor_chns[old], cur_chn);
else
cpumask_clear_cpu(old, &stor_device->alloced_cpus);
/* "Flush" the stor_chns array. */
for_each_possible_cpu(cpu) {
if (stor_device->stor_chns[cpu] && !cpumask_test_cpu(
cpu, &stor_device->alloced_cpus))
WRITE_ONCE(stor_device->stor_chns[cpu], NULL);
}
WRITE_ONCE(stor_device->stor_chns[new], channel);
cpumask_set_cpu(new, &stor_device->alloced_cpus);
spin_unlock_irqrestore(&stor_device->lock, flags);
}
static u64 storvsc_next_request_id(struct vmbus_channel *channel, u64 rqst_addr)
{
struct storvsc_cmd_request *request =
(struct storvsc_cmd_request *)(unsigned long)rqst_addr;
if (rqst_addr == VMBUS_RQST_INIT)
return VMBUS_RQST_INIT;
if (rqst_addr == VMBUS_RQST_RESET)
return VMBUS_RQST_RESET;
/*
* Cannot return an ID of 0, which is reserved for an unsolicited
* message from Hyper-V.
*/
return (u64)blk_mq_unique_tag(scsi_cmd_to_rq(request->cmd)) + 1;
}
static void handle_sc_creation(struct vmbus_channel *new_sc)
{
struct hv_device *device = new_sc->primary_channel->device_obj;
struct device *dev = &device->device;
struct storvsc_device *stor_device;
struct vmstorage_channel_properties props;
int ret;
stor_device = get_out_stor_device(device);
if (!stor_device)
return;
memset(&props, 0, sizeof(struct vmstorage_channel_properties));
new_sc->max_pkt_size = STORVSC_MAX_PKT_SIZE;
new_sc->next_request_id_callback = storvsc_next_request_id;
ret = vmbus_open(new_sc,
storvsc_ringbuffer_size,
storvsc_ringbuffer_size,
(void *)&props,
sizeof(struct vmstorage_channel_properties),
storvsc_on_channel_callback, new_sc);
/* In case vmbus_open() fails, we don't use the sub-channel. */
if (ret != 0) {
dev_err(dev, "Failed to open sub-channel: err=%d\n", ret);
return;
}
new_sc->change_target_cpu_callback = storvsc_change_target_cpu;
/* Add the sub-channel to the array of available channels. */
stor_device->stor_chns[new_sc->target_cpu] = new_sc;
cpumask_set_cpu(new_sc->target_cpu, &stor_device->alloced_cpus);
}
static void handle_multichannel_storage(struct hv_device *device, int max_chns)
{
struct device *dev = &device->device;
struct storvsc_device *stor_device;
int num_sc;
struct storvsc_cmd_request *request;
struct vstor_packet *vstor_packet;
int ret, t;
/*
* If the number of CPUs is artificially restricted, such as
* with maxcpus=1 on the kernel boot line, Hyper-V could offer
* sub-channels >= the number of CPUs. These sub-channels
* should not be created. The primary channel is already created
* and assigned to one CPU, so check against # CPUs - 1.
*/
num_sc = min((int)(num_online_cpus() - 1), max_chns);
if (!num_sc)
return;
stor_device = get_out_stor_device(device);
if (!stor_device)
return;
stor_device->num_sc = num_sc;
request = &stor_device->init_request;
vstor_packet = &request->vstor_packet;
/*
* Establish a handler for dealing with subchannels.
*/
vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
/*
* Request the host to create sub-channels.
*/
memset(request, 0, sizeof(struct storvsc_cmd_request));
init_completion(&request->wait_event);
vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
vstor_packet->flags = REQUEST_COMPLETION_FLAG;
vstor_packet->sub_channel_count = num_sc;
ret = vmbus_sendpacket(device->channel, vstor_packet,
sizeof(struct vstor_packet),
VMBUS_RQST_INIT,
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
if (ret != 0) {
dev_err(dev, "Failed to create sub-channel: err=%d\n", ret);
return;
}
t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
if (t == 0) {
dev_err(dev, "Failed to create sub-channel: timed out\n");
return;
}
if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
vstor_packet->status != 0) {
dev_err(dev, "Failed to create sub-channel: op=%d, sts=%d\n",
vstor_packet->operation, vstor_packet->status);
return;
}
/*
* We need to do nothing here, because vmbus_process_offer()
* invokes channel->sc_creation_callback, which will open and use
* the sub-channel(s).
*/
}
static void cache_wwn(struct storvsc_device *stor_device,
struct vstor_packet *vstor_packet)
{
/*
* Cache the currently active port and node ww names.
*/
if (vstor_packet->wwn_packet.primary_active) {
stor_device->node_name =
wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
stor_device->port_name =
wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
} else {
stor_device->node_name =
wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
stor_device->port_name =
wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
}
}
static int storvsc_execute_vstor_op(struct hv_device *device,
struct storvsc_cmd_request *request,
bool status_check)
{
struct storvsc_device *stor_device;
struct vstor_packet *vstor_packet;
int ret, t;
stor_device = get_out_stor_device(device);
if (!stor_device)
return -ENODEV;
vstor_packet = &request->vstor_packet;
init_completion(&request->wait_event);
vstor_packet->flags = REQUEST_COMPLETION_FLAG;
ret = vmbus_sendpacket(device->channel, vstor_packet,
sizeof(struct vstor_packet),
VMBUS_RQST_INIT,
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
if (ret != 0)
return ret;
t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
if (t == 0)
return -ETIMEDOUT;
if (!status_check)
return ret;
if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
vstor_packet->status != 0)
return -EINVAL;
return ret;
}
static int storvsc_channel_init(struct hv_device *device, bool is_fc)
{
struct storvsc_device *stor_device;
struct storvsc_cmd_request *request;
struct vstor_packet *vstor_packet;
int ret, i;
int max_chns;
bool process_sub_channels = false;
stor_device = get_out_stor_device(device);
if (!stor_device)
return -ENODEV;
request = &stor_device->init_request;
vstor_packet = &request->vstor_packet;
/*
* Now, initiate the vsc/vsp initialization protocol on the open
* channel
*/
memset(request, 0, sizeof(struct storvsc_cmd_request));
vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
ret = storvsc_execute_vstor_op(device, request, true);
if (ret)
return ret;
/*
* Query host supported protocol version.
*/
for (i = 0; i < ARRAY_SIZE(protocol_version); i++) {
/* reuse the packet for version range supported */
memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation =
VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
vstor_packet->version.major_minor = protocol_version[i];
/*
* The revision number is only used in Windows; set it to 0.
*/
vstor_packet->version.revision = 0;
ret = storvsc_execute_vstor_op(device, request, false);
if (ret != 0)
return ret;
if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
return -EINVAL;
if (vstor_packet->status == 0) {
vmstor_proto_version = protocol_version[i];
break;
}
}
if (vstor_packet->status != 0) {
dev_err(&device->device, "Obsolete Hyper-V version\n");
return -EINVAL;
}
memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
ret = storvsc_execute_vstor_op(device, request, true);
if (ret != 0)
return ret;
/*
* Check to see if multi-channel support is there.
* Hosts that implement protocol version of 5.1 and above
* support multi-channel.
*/
max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
/*
* Allocate state to manage the sub-channels.
* We allocate an array based on the numbers of possible CPUs
* (Hyper-V does not support cpu online/offline).
* This Array will be sparseley populated with unique
* channels - primary + sub-channels.
* We will however populate all the slots to evenly distribute
* the load.
*/
stor_device->stor_chns = kcalloc(num_possible_cpus(), sizeof(void *),
GFP_KERNEL);
if (stor_device->stor_chns == NULL)
return -ENOMEM;
device->channel->change_target_cpu_callback = storvsc_change_target_cpu;
stor_device->stor_chns[device->channel->target_cpu] = device->channel;
cpumask_set_cpu(device->channel->target_cpu,
&stor_device->alloced_cpus);
if (vstor_packet->storage_channel_properties.flags &
STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
process_sub_channels = true;
stor_device->max_transfer_bytes =
vstor_packet->storage_channel_properties.max_transfer_bytes;
if (!is_fc)
goto done;
/*
* For FC devices retrieve FC HBA data.
*/
memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
ret = storvsc_execute_vstor_op(device, request, true);
if (ret != 0)
return ret;
/*
* Cache the currently active port and node ww names.
*/
cache_wwn(stor_device, vstor_packet);
done:
memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
ret = storvsc_execute_vstor_op(device, request, true);
if (ret != 0)
return ret;
if (process_sub_channels)
handle_multichannel_storage(device, max_chns);
return ret;
}
static void storvsc_handle_error(struct vmscsi_request *vm_srb,
struct scsi_cmnd *scmnd,
struct Scsi_Host *host,
u8 asc, u8 ascq)
{
struct storvsc_scan_work *wrk;
void (*process_err_fn)(struct work_struct *work);
struct hv_host_device *host_dev = shost_priv(host);
switch (SRB_STATUS(vm_srb->srb_status)) {
case SRB_STATUS_ERROR:
case SRB_STATUS_ABORTED:
case SRB_STATUS_INVALID_REQUEST:
if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID) {
/* Check for capacity change */
if ((asc == 0x2a) && (ascq == 0x9)) {
process_err_fn = storvsc_device_scan;
/* Retry the I/O that triggered this. */
set_host_byte(scmnd, DID_REQUEUE);
goto do_work;
}
/*
* Check for "Operating parameters have changed"
* due to Hyper-V changing the VHD/VHDX BlockSize
* when adding/removing a differencing disk. This
* causes discard_granularity to change, so do a
* rescan to pick up the new granularity. We don't
* want scsi_report_sense() to output a message
* that a sysadmin wouldn't know what to do with.
*/
if ((asc == 0x3f) && (ascq != 0x03) &&