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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/scsi/storvsc_drv.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/scsi/storvsc_drv.c')
-rw-r--r--drivers/scsi/storvsc_drv.c2227
1 files changed, 2227 insertions, 0 deletions
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
new file mode 100644
index 000000000..c2d981d5a
--- /dev/null
+++ b/drivers/scsi/storvsc_drv.c
@@ -0,0 +1,2227 @@
+// 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);
+ 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) &&
+ (ascq != 0x0e)) {
+ process_err_fn = storvsc_device_scan;
+ set_host_byte(scmnd, DID_REQUEUE);
+ goto do_work;
+ }
+
+ /*
+ * Otherwise, let upper layer deal with the
+ * error when sense message is present
+ */
+ 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;
+
+ case SRB_STATUS_INVALID_LUN:
+ set_host_byte(scmnd, DID_NO_CONNECT);
+ process_err_fn = storvsc_remove_lun;
+ goto do_work;
+
+ }
+ 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_BAD_TARGET);
+ 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;
+ unsigned long time_limit = jiffies + msecs_to_jiffies(CALLBACK_TIMEOUT);
+
+ 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 (unlikely(time_after(jiffies, time_limit))) {
+ hv_pkt_iter_close(channel);
+ return;
+ }
+
+ 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));
+
+ /* storvsc devices don't support MAINTENANCE_IN SCSI cmd */
+ sdevice->no_report_opcodes = 1;
+ 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)
+{
+ 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 = 0;
+
+ 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;
+
+ payload_sz = (hvpg_count * sizeof(u64) +
+ sizeof(struct vmbus_packet_mpb_array));
+
+ if (hvpg_count > MAX_PAGE_BUFFER_COUNT) {
+ 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)
+ scsi_dma_unmap(scmnd);
+
+ 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);
+ if (is_fc)
+ max_xfer_bytes = min(max_xfer_bytes, STORVSC_FC_MAX_XFER_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",
+ 0,
+ 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
+ * 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);