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linux/drivers/scsi/storvsc_drv.c
Saurabh Sengar 1d3e098078 scsi: storvsc: Correct reporting of Hyper-V I/O size limits 
Current code is based on the idea that the max number of SGL entries
also determines the max size of an I/O request.  While this idea was
true in older versions of the storvsc driver when SGL entry length
was limited to 4 Kbytes, commit 3d9c3dcc58 ("scsi: storvsc: Enable
scatterlist entry lengths > 4Kbytes") removed that limitation. It's
now theoretically possible for the block layer to send requests that
exceed the maximum size supported by Hyper-V. This problem doesn't
currently happen in practice because the block layer defaults to a
512 Kbyte maximum, while Hyper-V in Azure supports 2 Mbyte I/O sizes.
But some future configuration of Hyper-V could have a smaller max I/O
size, and the block layer could exceed that max.

Fix this by correctly setting max_sectors as well as sg_tablesize to
reflect the maximum I/O size that Hyper-V reports. While allowing
I/O sizes larger than the block layer default of 512 Kbytes doesn’t
provide any noticeable performance benefit in the tests we ran, it's
still appropriate to report the correct underlying Hyper-V capabilities
to the Linux block layer.

Also tweak the virt_boundary_mask to reflect that the required
alignment derives from Hyper-V communication using a 4 Kbyte page size,
and not on the guest page size, which might be bigger (eg. ARM64).

Link: https://lore.kernel.org/r/1655190355-28722-1-git-send-email-ssengar@linux.microsoft.com
Fixes: 3d9c3dcc58 ("scsi: storvsc: Enable scatter list entry lengths > 4Kbytes")
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-16 21:36:03 -04:00

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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)
/* 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; a subset of the codes used here.
*/
#define SRB_STATUS_AUTOSENSE_VALID 0x80
#define SRB_STATUS_QUEUE_FROZEN 0x40
#define SRB_STATUS_INVALID_LUN 0x20
#define SRB_STATUS_SUCCESS 0x01
#define SRB_STATUS_ABORTED 0x02
#define SRB_STATUS_ERROR 0x04
#define SRB_STATUS_DATA_OVERRUN 0x12
#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_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);
/*
* In some situations, Hyper-V sets multiple bits in the
* srb_status, such as ABORTED and ERROR. So process them
* individually, with the most specific bits first.
*/
if (vm_srb->srb_status & SRB_STATUS_INVALID_LUN) {
set_host_byte(scmnd, DID_NO_CONNECT);
process_err_fn = storvsc_remove_lun;
goto do_work;
}
if (vm_srb->srb_status & SRB_STATUS_ABORTED) {
if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID &&
/* Capacity data has changed */
(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;
}
}
if (vm_srb->srb_status & SRB_STATUS_ERROR) {
/*
* Let upper layer deal with error when
* sense message is present.
*/
if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID)
return;
/*
* If there is an error; offline the device since all
* error recovery strategies would have already been
* deployed on the host side. However, if the command
* were a pass-through command deal with it appropriately.
*/
switch (scmnd->cmnd[0]) {
case ATA_16:
case ATA_12:
set_host_byte(scmnd, DID_PASSTHROUGH);
break;
/*
* On some Hyper-V hosts TEST_UNIT_READY command can
* return SRB_STATUS_ERROR. Let the upper level code
* deal with it based on the sense information.
*/
case TEST_UNIT_READY:
break;
default:
set_host_byte(scmnd, DID_ERROR);
}
}
return;
do_work:
/*
* We need to schedule work to process this error; schedule it.
*/
wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
if (!wrk) {
set_host_byte(scmnd, DID_TARGET_FAILURE);
return;
}
wrk->host = host;
wrk->lun = vm_srb->lun;
wrk->tgt_id = vm_srb->target_id;
INIT_WORK(&wrk->work, process_err_fn);
queue_work(host_dev->handle_error_wq, &wrk->work);
}
static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
struct storvsc_device *stor_dev)
{
struct scsi_cmnd *scmnd = cmd_request->cmd;
struct scsi_sense_hdr sense_hdr;
struct vmscsi_request *vm_srb;
u32 data_transfer_length;
struct Scsi_Host *host;
u32 payload_sz = cmd_request->payload_sz;
void *payload = cmd_request->payload;
bool sense_ok;
host = stor_dev->host;
vm_srb = &cmd_request->vstor_packet.vm_srb;
data_transfer_length = vm_srb->data_transfer_length;
scmnd->result = vm_srb->scsi_status;
if (scmnd->result) {
sense_ok = scsi_normalize_sense(scmnd->sense_buffer,
SCSI_SENSE_BUFFERSIZE, &sense_hdr);
if (sense_ok && do_logging(STORVSC_LOGGING_WARN))
scsi_print_sense_hdr(scmnd->device, "storvsc",
&sense_hdr);
}
if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
sense_hdr.ascq);
/*
* The Windows driver set data_transfer_length on
* SRB_STATUS_DATA_OVERRUN. On other errors, this value
* is untouched. In these cases we set it to 0.
*/
if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
data_transfer_length = 0;
}
/* Validate data_transfer_length (from Hyper-V) */
if (data_transfer_length > cmd_request->payload->range.len)
data_transfer_length = cmd_request->payload->range.len;
scsi_set_resid(scmnd,
cmd_request->payload->range.len - data_transfer_length);
scsi_done(scmnd);
if (payload_sz >
sizeof(struct vmbus_channel_packet_multipage_buffer))
kfree(payload);
}
static void storvsc_on_io_completion(struct storvsc_device *stor_device,
struct vstor_packet *vstor_packet,
struct storvsc_cmd_request *request)
{
struct vstor_packet *stor_pkt;
struct hv_device *device = stor_device->device;
stor_pkt = &request->vstor_packet;
/*
* The current SCSI handling on the host side does
* not correctly handle:
* INQUIRY command with page code parameter set to 0x80
* MODE_SENSE command with cmd[2] == 0x1c
*
* Setup srb and scsi status so this won't be fatal.
* We do this so we can distinguish truly fatal failues
* (srb status == 0x4) and off-line the device in that case.
*/
if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
(stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
vstor_packet->vm_srb.scsi_status = 0;
vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
}
/* Copy over the status...etc */
stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
/*
* Copy over the sense_info_length, but limit to the known max
* size if Hyper-V returns a bad value.
*/
stor_pkt->vm_srb.sense_info_length = min_t(u8, STORVSC_SENSE_BUFFER_SIZE,
vstor_packet->vm_srb.sense_info_length);
if (vstor_packet->vm_srb.scsi_status != 0 ||
vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS) {
/*
* Log TEST_UNIT_READY errors only as warnings. Hyper-V can
* return errors when detecting devices using TEST_UNIT_READY,
* and logging these as errors produces unhelpful noise.
*/
int loglevel = (stor_pkt->vm_srb.cdb[0] == TEST_UNIT_READY) ?
STORVSC_LOGGING_WARN : STORVSC_LOGGING_ERROR;
storvsc_log(device, loglevel,
"tag#%d cmd 0x%x status: scsi 0x%x srb 0x%x hv 0x%x\n",
scsi_cmd_to_rq(request->cmd)->tag,
stor_pkt->vm_srb.cdb[0],
vstor_packet->vm_srb.scsi_status,
vstor_packet->vm_srb.srb_status,
vstor_packet->status);
}
if (vstor_packet->vm_srb.scsi_status == SAM_STAT_CHECK_CONDITION &&
(vstor_packet->vm_srb.srb_status & SRB_STATUS_AUTOSENSE_VALID))
memcpy(request->cmd->sense_buffer,
vstor_packet->vm_srb.sense_data,
stor_pkt->vm_srb.sense_info_length);
stor_pkt->vm_srb.data_transfer_length =
vstor_packet->vm_srb.data_transfer_length;
storvsc_command_completion(request, stor_device);
if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
stor_device->drain_notify)
wake_up(&stor_device->waiting_to_drain);
}
static void storvsc_on_receive(struct storvsc_device *stor_device,
struct vstor_packet *vstor_packet,
struct storvsc_cmd_request *request)
{
struct hv_host_device *host_dev;
switch (vstor_packet->operation) {
case VSTOR_OPERATION_COMPLETE_IO:
storvsc_on_io_completion(stor_device, vstor_packet, request);
break;
case VSTOR_OPERATION_REMOVE_DEVICE:
case VSTOR_OPERATION_ENUMERATE_BUS:
host_dev = shost_priv(stor_device->host);
queue_work(
host_dev->handle_error_wq, &host_dev->host_scan_work);
break;
case VSTOR_OPERATION_FCHBA_DATA:
cache_wwn(stor_device, vstor_packet);
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
fc_host_node_name(stor_device->host) = stor_device->node_name;
fc_host_port_name(stor_device->host) = stor_device->port_name;
#endif
break;
default:
break;
}
}
static void storvsc_on_channel_callback(void *context)
{
struct vmbus_channel *channel = (struct vmbus_channel *)context;
const struct vmpacket_descriptor *desc;
struct hv_device *device;
struct storvsc_device *stor_device;
struct Scsi_Host *shost;
if (channel->primary_channel != NULL)
device = channel->primary_channel->device_obj;
else
device = channel->device_obj;
stor_device = get_in_stor_device(device);
if (!stor_device)
return;
shost = stor_device->host;
foreach_vmbus_pkt(desc, channel) {
struct vstor_packet *packet = hv_pkt_data(desc);
struct storvsc_cmd_request *request = NULL;
u32 pktlen = hv_pkt_datalen(desc);
u64 rqst_id = desc->trans_id;
u32 minlen = rqst_id ? sizeof(struct vstor_packet) :
sizeof(enum vstor_packet_operation);
if (pktlen < minlen) {
dev_err(&device->device,
"Invalid pkt: id=%llu, len=%u, minlen=%u\n",
rqst_id, pktlen, minlen);
continue;
}
if (rqst_id == VMBUS_RQST_INIT) {
request = &stor_device->init_request;
} else if (rqst_id == VMBUS_RQST_RESET) {
request = &stor_device->reset_request;
} else {
/* Hyper-V can send an unsolicited message with ID of 0 */
if (rqst_id == 0) {
/*
* storvsc_on_receive() looks at the vstor_packet in the message
* from the ring buffer.
*
* - If the operation in the vstor_packet is COMPLETE_IO, then
* we call storvsc_on_io_completion(), and dereference the
* guest memory address. Make sure we don't call
* storvsc_on_io_completion() with a guest memory address
* that is zero if Hyper-V were to construct and send such
* a bogus packet.
*
* - If the operation in the vstor_packet is FCHBA_DATA, then
* we call cache_wwn(), and access the data payload area of
* the packet (wwn_packet); however, there is no guarantee
* that the packet is big enough to contain such area.
* Future-proof the code by rejecting such a bogus packet.
*/
if (packet->operation == VSTOR_OPERATION_COMPLETE_IO ||
packet->operation == VSTOR_OPERATION_FCHBA_DATA) {
dev_err(&device->device, "Invalid packet with ID of 0\n");
continue;
}
} else {
struct scsi_cmnd *scmnd;
/* Transaction 'rqst_id' corresponds to tag 'rqst_id - 1' */
scmnd = scsi_host_find_tag(shost, rqst_id - 1);
if (scmnd == NULL) {
dev_err(&device->device, "Incorrect transaction ID\n");
continue;
}
request = (struct storvsc_cmd_request *)scsi_cmd_priv(scmnd);
scsi_dma_unmap(scmnd);
}
storvsc_on_receive(stor_device, packet, request);
continue;
}
memcpy(&request->vstor_packet, packet,
sizeof(struct vstor_packet));
complete(&request->wait_event);
}
}
static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
bool is_fc)
{
struct vmstorage_channel_properties props;
int ret;
memset(&props, 0, sizeof(struct vmstorage_channel_properties));
device->channel->max_pkt_size = STORVSC_MAX_PKT_SIZE;
device->channel->next_request_id_callback = storvsc_next_request_id;
ret = vmbus_open(device->channel,
ring_size,
ring_size,
(void *)&props,
sizeof(struct vmstorage_channel_properties),
storvsc_on_channel_callback, device->channel);
if (ret != 0)
return ret;
ret = storvsc_channel_init(device, is_fc);
return ret;
}
static int storvsc_dev_remove(struct hv_device *device)
{
struct storvsc_device *stor_device;
stor_device = hv_get_drvdata(device);
stor_device->destroy = true;
/* Make sure flag is set before waiting */
wmb();
/*
* At this point, all outbound traffic should be disable. We
* only allow inbound traffic (responses) to proceed so that
* outstanding requests can be completed.
*/
storvsc_wait_to_drain(stor_device);
/*
* Since we have already drained, we don't need to busy wait
* as was done in final_release_stor_device()
* Note that we cannot set the ext pointer to NULL until
* we have drained - to drain the outgoing packets, we need to
* allow incoming packets.
*/
hv_set_drvdata(device, NULL);
/* Close the channel */
vmbus_close(device->channel);
kfree(stor_device->stor_chns);
kfree(stor_device);
return 0;
}
static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device,
u16 q_num)
{
u16 slot = 0;
u16 hash_qnum;
const struct cpumask *node_mask;
int num_channels, tgt_cpu;
if (stor_device->num_sc == 0) {
stor_device->stor_chns[q_num] = stor_device->device->channel;
return stor_device->device->channel;
}
/*
* Our channel array is sparsley populated and we
* initiated I/O on a processor/hw-q that does not
* currently have a designated channel. Fix this.
* The strategy is simple:
* I. Ensure NUMA locality
* II. Distribute evenly (best effort)
*/
node_mask = cpumask_of_node(cpu_to_node(q_num));
num_channels = 0;
for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
if (cpumask_test_cpu(tgt_cpu, node_mask))
num_channels++;
}
if (num_channels == 0) {
stor_device->stor_chns[q_num] = stor_device->device->channel;
return stor_device->device->channel;
}
hash_qnum = q_num;
while (hash_qnum >= num_channels)
hash_qnum -= num_channels;
for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
if (!cpumask_test_cpu(tgt_cpu, node_mask))
continue;
if (slot == hash_qnum)
break;
slot++;
}
stor_device->stor_chns[q_num] = stor_device->stor_chns[tgt_cpu];
return stor_device->stor_chns[q_num];
}
static int storvsc_do_io(struct hv_device *device,
struct storvsc_cmd_request *request, u16 q_num)
{
struct storvsc_device *stor_device;
struct vstor_packet *vstor_packet;
struct vmbus_channel *outgoing_channel, *channel;
unsigned long flags;
int ret = 0;
const struct cpumask *node_mask;
int tgt_cpu;
vstor_packet = &request->vstor_packet;
stor_device = get_out_stor_device(device);
if (!stor_device)
return -ENODEV;
request->device = device;
/*
* Select an appropriate channel to send the request out.
*/
/* See storvsc_change_target_cpu(). */
outgoing_channel = READ_ONCE(stor_device->stor_chns[q_num]);
if (outgoing_channel != NULL) {
if (outgoing_channel->target_cpu == q_num) {
/*
* Ideally, we want to pick a different channel if
* available on the same NUMA node.
*/
node_mask = cpumask_of_node(cpu_to_node(q_num));
for_each_cpu_wrap(tgt_cpu,
&stor_device->alloced_cpus, q_num + 1) {
if (!cpumask_test_cpu(tgt_cpu, node_mask))
continue;
if (tgt_cpu == q_num)
continue;
channel = READ_ONCE(
stor_device->stor_chns[tgt_cpu]);
if (channel == NULL)
continue;
if (hv_get_avail_to_write_percent(
&channel->outbound)
> ring_avail_percent_lowater) {
outgoing_channel = channel;
goto found_channel;
}
}
/*
* All the other channels on the same NUMA node are
* busy. Try to use the channel on the current CPU
*/
if (hv_get_avail_to_write_percent(
&outgoing_channel->outbound)
> ring_avail_percent_lowater)
goto found_channel;
/*
* If we reach here, all the channels on the current
* NUMA node are busy. Try to find a channel in
* other NUMA nodes
*/
for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
if (cpumask_test_cpu(tgt_cpu, node_mask))
continue;
channel = READ_ONCE(
stor_device->stor_chns[tgt_cpu]);
if (channel == NULL)
continue;
if (hv_get_avail_to_write_percent(
&channel->outbound)
> ring_avail_percent_lowater) {
outgoing_channel = channel;
goto found_channel;
}
}
}
} else {
spin_lock_irqsave(&stor_device->lock, flags);
outgoing_channel = stor_device->stor_chns[q_num];
if (outgoing_channel != NULL) {
spin_unlock_irqrestore(&stor_device->lock, flags);
goto found_channel;
}
outgoing_channel = get_og_chn(stor_device, q_num);
spin_unlock_irqrestore(&stor_device->lock, flags);
}
found_channel:
vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
vstor_packet->vm_srb.sense_info_length = STORVSC_SENSE_BUFFER_SIZE;
vstor_packet->vm_srb.data_transfer_length =
request->payload->range.len;
vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
if (request->payload->range.len) {
ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
request->payload, request->payload_sz,
vstor_packet,
sizeof(struct vstor_packet),
(unsigned long)request);
} else {
ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
sizeof(struct vstor_packet),
(unsigned long)request,
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
}
if (ret != 0)
return ret;
atomic_inc(&stor_device->num_outstanding_req);
return ret;
}
static int storvsc_device_alloc(struct scsi_device *sdevice)
{
/*
* Set blist flag to permit the reading of the VPD pages even when
* the target may claim SPC-2 compliance. MSFT targets currently
* claim SPC-2 compliance while they implement post SPC-2 features.
* With this flag we can correctly handle WRITE_SAME_16 issues.
*
* Hypervisor reports SCSI_UNKNOWN type for DVD ROM device but
* still supports REPORT LUN.
*/
sdevice->sdev_bflags = BLIST_REPORTLUN2 | BLIST_TRY_VPD_PAGES;
return 0;
}
static int storvsc_device_configure(struct scsi_device *sdevice)
{
blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
sdevice->no_write_same = 1;
/*
* If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
* if the device is a MSFT virtual device. If the host is
* WIN10 or newer, allow write_same.
*/
if (!strncmp(sdevice->vendor, "Msft", 4)) {
switch (vmstor_proto_version) {
case VMSTOR_PROTO_VERSION_WIN8:
case VMSTOR_PROTO_VERSION_WIN8_1:
sdevice->scsi_level = SCSI_SPC_3;
break;
}
if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
sdevice->no_write_same = 0;
}
return 0;
}
static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
sector_t capacity, int *info)
{
sector_t nsect = capacity;
sector_t cylinders = nsect;
int heads, sectors_pt;
/*
* We are making up these values; let us keep it simple.
*/
heads = 0xff;
sectors_pt = 0x3f; /* Sectors per track */
sector_div(cylinders, heads * sectors_pt);
if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
cylinders = 0xffff;
info[0] = heads;
info[1] = sectors_pt;
info[2] = (int)cylinders;
return 0;
}
static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
{
struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
struct hv_device *device = host_dev->dev;
struct storvsc_device *stor_device;
struct storvsc_cmd_request *request;
struct vstor_packet *vstor_packet;
int ret, t;
stor_device = get_out_stor_device(device);
if (!stor_device)
return FAILED;
request = &stor_device->reset_request;
vstor_packet = &request->vstor_packet;
memset(vstor_packet, 0, sizeof(struct vstor_packet));
init_completion(&request->wait_event);
vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
vstor_packet->flags = REQUEST_COMPLETION_FLAG;
vstor_packet->vm_srb.path_id = stor_device->path_id;
ret = vmbus_sendpacket(device->channel, vstor_packet,
sizeof(struct vstor_packet),
VMBUS_RQST_RESET,
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
if (ret != 0)
return FAILED;
t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
if (t == 0)
return TIMEOUT_ERROR;
/*
* At this point, all outstanding requests in the adapter
* should have been flushed out and return to us
* There is a potential race here where the host may be in
* the process of responding when we return from here.
* Just wait for all in-transit packets to be accounted for
* before we return from here.
*/
storvsc_wait_to_drain(stor_device);
return SUCCESS;
}
/*
* The host guarantees to respond to each command, although I/O latencies might
* be unbounded on Azure. Reset the timer unconditionally to give the host a
* chance to perform EH.
*/
static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
{
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
if (scmnd->device->host->transportt == fc_transport_template)
return fc_eh_timed_out(scmnd);
#endif
return BLK_EH_RESET_TIMER;
}
static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
{
bool allowed = true;
u8 scsi_op = scmnd->cmnd[0];
switch (scsi_op) {
/* the host does not handle WRITE_SAME, log accident usage */
case WRITE_SAME:
/*
* smartd sends this command and the host does not handle
* this. So, don't send it.
*/
case SET_WINDOW:
set_host_byte(scmnd, DID_ERROR);
allowed = false;
break;
default:
break;
}
return allowed;
}
static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
{
int ret;
struct hv_host_device *host_dev = shost_priv(host);
struct hv_device *dev = host_dev->dev;
struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
struct scatterlist *sgl;
struct vmscsi_request *vm_srb;
struct vmbus_packet_mpb_array *payload;
u32 payload_sz;
u32 length;
if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
/*
* On legacy hosts filter unimplemented commands.
* Future hosts are expected to correctly handle
* unsupported commands. Furthermore, it is
* possible that some of the currently
* unsupported commands maybe supported in
* future versions of the host.
*/
if (!storvsc_scsi_cmd_ok(scmnd)) {
scsi_done(scmnd);
return 0;
}
}
/* Setup the cmd request */
cmd_request->cmd = scmnd;
memset(&cmd_request->vstor_packet, 0, sizeof(struct vstor_packet));
vm_srb = &cmd_request->vstor_packet.vm_srb;
vm_srb->time_out_value = 60;
vm_srb->srb_flags |=
SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
if (scmnd->device->tagged_supported) {
vm_srb->srb_flags |=
(SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
vm_srb->queue_tag = SP_UNTAGGED;
vm_srb->queue_action = SRB_SIMPLE_TAG_REQUEST;
}
/* Build the SRB */
switch (scmnd->sc_data_direction) {
case DMA_TO_DEVICE:
vm_srb->data_in = WRITE_TYPE;
vm_srb->srb_flags |= SRB_FLAGS_DATA_OUT;
break;
case DMA_FROM_DEVICE:
vm_srb->data_in = READ_TYPE;
vm_srb->srb_flags |= SRB_FLAGS_DATA_IN;
break;
case DMA_NONE:
vm_srb->data_in = UNKNOWN_TYPE;
vm_srb->srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
break;
default:
/*
* This is DMA_BIDIRECTIONAL or something else we are never
* supposed to see here.
*/
WARN(1, "Unexpected data direction: %d\n",
scmnd->sc_data_direction);
return -EINVAL;
}
vm_srb->port_number = host_dev->port;
vm_srb->path_id = scmnd->device->channel;
vm_srb->target_id = scmnd->device->id;
vm_srb->lun = scmnd->device->lun;
vm_srb->cdb_length = scmnd->cmd_len;
memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
sgl = (struct scatterlist *)scsi_sglist(scmnd);
length = scsi_bufflen(scmnd);
payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
payload_sz = sizeof(cmd_request->mpb);
if (scsi_sg_count(scmnd)) {
unsigned long offset_in_hvpg = offset_in_hvpage(sgl->offset);
unsigned int hvpg_count = HVPFN_UP(offset_in_hvpg + length);
struct scatterlist *sg;
unsigned long hvpfn, hvpfns_to_add;
int j, i = 0, sg_count;
if (hvpg_count > MAX_PAGE_BUFFER_COUNT) {
payload_sz = (hvpg_count * sizeof(u64) +
sizeof(struct vmbus_packet_mpb_array));
payload = kzalloc(payload_sz, GFP_ATOMIC);
if (!payload)
return SCSI_MLQUEUE_DEVICE_BUSY;
}
payload->range.len = length;
payload->range.offset = offset_in_hvpg;
sg_count = scsi_dma_map(scmnd);
if (sg_count < 0) {
ret = SCSI_MLQUEUE_DEVICE_BUSY;
goto err_free_payload;
}
for_each_sg(sgl, sg, sg_count, j) {
/*
* Init values for the current sgl entry. hvpfns_to_add
* is in units of Hyper-V size pages. Handling the
* PAGE_SIZE != HV_HYP_PAGE_SIZE case also handles
* values of sgl->offset that are larger than PAGE_SIZE.
* Such offsets are handled even on other than the first
* sgl entry, provided they are a multiple of PAGE_SIZE.
*/
hvpfn = HVPFN_DOWN(sg_dma_address(sg));
hvpfns_to_add = HVPFN_UP(sg_dma_address(sg) +
sg_dma_len(sg)) - hvpfn;
/*
* Fill the next portion of the PFN array with
* sequential Hyper-V PFNs for the continguous physical
* memory described by the sgl entry. The end of the
* last sgl should be reached at the same time that
* the PFN array is filled.
*/
while (hvpfns_to_add--)
payload->range.pfn_array[i++] = hvpfn++;
}
}
cmd_request->payload = payload;
cmd_request->payload_sz = payload_sz;
/* Invokes the vsc to start an IO */
ret = storvsc_do_io(dev, cmd_request, get_cpu());
put_cpu();
if (ret == -EAGAIN) {
/* no more space */
ret = SCSI_MLQUEUE_DEVICE_BUSY;
goto err_free_payload;
}
return 0;
err_free_payload:
if (payload_sz > sizeof(cmd_request->mpb))
kfree(payload);
return ret;
}
static struct scsi_host_template scsi_driver = {
.module = THIS_MODULE,
.name = "storvsc_host_t",
.cmd_size = sizeof(struct storvsc_cmd_request),
.bios_param = storvsc_get_chs,
.queuecommand = storvsc_queuecommand,
.eh_host_reset_handler = storvsc_host_reset_handler,
.proc_name = "storvsc_host",
.eh_timed_out = storvsc_eh_timed_out,
.slave_alloc = storvsc_device_alloc,
.slave_configure = storvsc_device_configure,
.cmd_per_lun = 2048,
.this_id = -1,
/* Ensure there are no gaps in presented sgls */
.virt_boundary_mask = HV_HYP_PAGE_SIZE - 1,
.no_write_same = 1,
.track_queue_depth = 1,
.change_queue_depth = storvsc_change_queue_depth,
};
enum {
SCSI_GUID,
IDE_GUID,
SFC_GUID,
};
static const struct hv_vmbus_device_id id_table[] = {
/* SCSI guid */
{ HV_SCSI_GUID,
.driver_data = SCSI_GUID
},
/* IDE guid */
{ HV_IDE_GUID,
.driver_data = IDE_GUID
},
/* Fibre Channel GUID */
{
HV_SYNTHFC_GUID,
.driver_data = SFC_GUID
},
{ },
};
MODULE_DEVICE_TABLE(vmbus, id_table);
static const struct { guid_t guid; } fc_guid = { HV_SYNTHFC_GUID };
static bool hv_dev_is_fc(struct hv_device *hv_dev)
{
return guid_equal(&fc_guid.guid, &hv_dev->dev_type);
}
static int storvsc_probe(struct hv_device *device,
const struct hv_vmbus_device_id *dev_id)
{
int ret;
int num_cpus = num_online_cpus();
int num_present_cpus = num_present_cpus();
struct Scsi_Host *host;
struct hv_host_device *host_dev;
bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
int target = 0;
struct storvsc_device *stor_device;
int max_sub_channels = 0;
u32 max_xfer_bytes;
/*
* We support sub-channels for storage on SCSI and FC controllers.
* The number of sub-channels offerred is based on the number of
* VCPUs in the guest.
*/
if (!dev_is_ide)
max_sub_channels =
(num_cpus - 1) / storvsc_vcpus_per_sub_channel;
scsi_driver.can_queue = max_outstanding_req_per_channel *
(max_sub_channels + 1) *
(100 - ring_avail_percent_lowater) / 100;
host = scsi_host_alloc(&scsi_driver,
sizeof(struct hv_host_device));
if (!host)
return -ENOMEM;
host_dev = shost_priv(host);
memset(host_dev, 0, sizeof(struct hv_host_device));
host_dev->port = host->host_no;
host_dev->dev = device;
host_dev->host = host;
stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
if (!stor_device) {
ret = -ENOMEM;
goto err_out0;
}
stor_device->destroy = false;
init_waitqueue_head(&stor_device->waiting_to_drain);
stor_device->device = device;
stor_device->host = host;
spin_lock_init(&stor_device->lock);
hv_set_drvdata(device, stor_device);
dma_set_min_align_mask(&device->device, HV_HYP_PAGE_SIZE - 1);
stor_device->port_number = host->host_no;
ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size, is_fc);
if (ret)
goto err_out1;
host_dev->path = stor_device->path_id;
host_dev->target = stor_device->target_id;
switch (dev_id->driver_data) {
case SFC_GUID:
host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
host->max_id = STORVSC_FC_MAX_TARGETS;
host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
host->transportt = fc_transport_template;
#endif
break;
case SCSI_GUID:
host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
host->max_id = STORVSC_MAX_TARGETS;
host->max_channel = STORVSC_MAX_CHANNELS - 1;
break;
default:
host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
host->max_id = STORVSC_IDE_MAX_TARGETS;
host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
break;
}
/* max cmd length */
host->max_cmd_len = STORVSC_MAX_CMD_LEN;
/*
* Any reasonable Hyper-V configuration should provide
* max_transfer_bytes value aligning to HV_HYP_PAGE_SIZE,
* protecting it from any weird value.
*/
max_xfer_bytes = round_down(stor_device->max_transfer_bytes, HV_HYP_PAGE_SIZE);
/* max_hw_sectors_kb */
host->max_sectors = max_xfer_bytes >> 9;
/*
* There are 2 requirements for Hyper-V storvsc sgl segments,
* based on which the below calculation for max segments is
* done:
*
* 1. Except for the first and last sgl segment, all sgl segments
* should be align to HV_HYP_PAGE_SIZE, that also means the
* maximum number of segments in a sgl can be calculated by
* dividing the total max transfer length by HV_HYP_PAGE_SIZE.
*
* 2. Except for the first and last, each entry in the SGL must
* have an offset that is a multiple of HV_HYP_PAGE_SIZE.
*/
host->sg_tablesize = (max_xfer_bytes >> HV_HYP_PAGE_SHIFT) + 1;
/*
* For non-IDE disks, the host supports multiple channels.
* Set the number of HW queues we are supporting.
*/
if (!dev_is_ide) {
if (storvsc_max_hw_queues > num_present_cpus) {
storvsc_max_hw_queues = 0;
storvsc_log(device, STORVSC_LOGGING_WARN,
"Resetting invalid storvsc_max_hw_queues value to default.\n");
}
if (storvsc_max_hw_queues)
host->nr_hw_queues = storvsc_max_hw_queues;
else
host->nr_hw_queues = num_present_cpus;
}
/*
* Set the error handler work queue.
*/
host_dev->handle_error_wq =
alloc_ordered_workqueue("storvsc_error_wq_%d",
WQ_MEM_RECLAIM,
host->host_no);
if (!host_dev->handle_error_wq) {
ret = -ENOMEM;
goto err_out2;
}
INIT_WORK(&host_dev->host_scan_work, storvsc_host_scan);
/* Register the HBA and start the scsi bus scan */
ret = scsi_add_host(host, &device->device);
if (ret != 0)
goto err_out3;
if (!dev_is_ide) {
scsi_scan_host(host);
} else {
target = (device->dev_instance.b[5] << 8 |
device->dev_instance.b[4]);
ret = scsi_add_device(host, 0, target, 0);
if (ret)
goto err_out4;
}
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
if (host->transportt == fc_transport_template) {
struct fc_rport_identifiers ids = {
.roles = FC_PORT_ROLE_FCP_DUMMY_INITIATOR,
};
fc_host_node_name(host) = stor_device->node_name;
fc_host_port_name(host) = stor_device->port_name;
stor_device->rport = fc_remote_port_add(host, 0, &ids);
if (!stor_device->rport) {
ret = -ENOMEM;
goto err_out4;
}
}
#endif
return 0;
err_out4:
scsi_remove_host(host);
err_out3:
destroy_workqueue(host_dev->handle_error_wq);
err_out2:
/*
* Once we have connected with the host, we would need to
* to invoke storvsc_dev_remove() to rollback this state and
* this call also frees up the stor_device; hence the jump around
* err_out1 label.
*/
storvsc_dev_remove(device);
goto err_out0;
err_out1:
kfree(stor_device->stor_chns);
kfree(stor_device);
err_out0:
scsi_host_put(host);
return ret;
}
/* Change a scsi target's queue depth */
static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth)
{
if (queue_depth > scsi_driver.can_queue)
queue_depth = scsi_driver.can_queue;
return scsi_change_queue_depth(sdev, queue_depth);
}
static int storvsc_remove(struct hv_device *dev)
{
struct storvsc_device *stor_device = hv_get_drvdata(dev);
struct Scsi_Host *host = stor_device->host;
struct hv_host_device *host_dev = shost_priv(host);
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
if (host->transportt == fc_transport_template) {
fc_remote_port_delete(stor_device->rport);
fc_remove_host(host);
}
#endif
destroy_workqueue(host_dev->handle_error_wq);
scsi_remove_host(host);
storvsc_dev_remove(dev);
scsi_host_put(host);
return 0;
}
static int storvsc_suspend(struct hv_device *hv_dev)
{
struct storvsc_device *stor_device = hv_get_drvdata(hv_dev);
struct Scsi_Host *host = stor_device->host;
struct hv_host_device *host_dev = shost_priv(host);
storvsc_wait_to_drain(stor_device);
drain_workqueue(host_dev->handle_error_wq);
vmbus_close(hv_dev->channel);
kfree(stor_device->stor_chns);
stor_device->stor_chns = NULL;
cpumask_clear(&stor_device->alloced_cpus);
return 0;
}
static int storvsc_resume(struct hv_device *hv_dev)
{
int ret;
ret = storvsc_connect_to_vsp(hv_dev, storvsc_ringbuffer_size,
hv_dev_is_fc(hv_dev));
return ret;
}
static struct hv_driver storvsc_drv = {
.name = KBUILD_MODNAME,
.id_table = id_table,
.probe = storvsc_probe,
.remove = storvsc_remove,
.suspend = storvsc_suspend,
.resume = storvsc_resume,
.driver = {
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
static struct fc_function_template fc_transport_functions = {
.show_host_node_name = 1,
.show_host_port_name = 1,
};
#endif
static int __init storvsc_drv_init(void)
{
int ret;
/*
* Divide the ring buffer data size (which is 1 page less
* than the ring buffer size since that page is reserved for
* the ring buffer indices) by the max request size (which is
* vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
*/
max_outstanding_req_per_channel =
((storvsc_ringbuffer_size - PAGE_SIZE) /
ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
sizeof(struct vstor_packet) + sizeof(u64),
sizeof(u64)));
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
fc_transport_template = fc_attach_transport(&fc_transport_functions);
if (!fc_transport_template)
return -ENODEV;
#endif
ret = vmbus_driver_register(&storvsc_drv);
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
if (ret)
fc_release_transport(fc_transport_template);
#endif
return ret;
}
static void __exit storvsc_drv_exit(void)
{
vmbus_driver_unregister(&storvsc_drv);
#if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
fc_release_transport(fc_transport_template);
#endif
}
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
module_init(storvsc_drv_init);
module_exit(storvsc_drv_exit);
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