v4.19.13 snapshot.
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
new file mode 100644
index 0000000..87d3d7d
--- /dev/null
+++ b/drivers/hv/hyperv_vmbus.h
@@ -0,0 +1,443 @@
+/*
+ *
+ * Copyright (c) 2011, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *   K. Y. Srinivasan <kys@microsoft.com>
+ *
+ */
+
+#ifndef _HYPERV_VMBUS_H
+#define _HYPERV_VMBUS_H
+
+#include <linux/list.h>
+#include <asm/sync_bitops.h>
+#include <asm/hyperv-tlfs.h>
+#include <linux/atomic.h>
+#include <linux/hyperv.h>
+#include <linux/interrupt.h>
+
+#include "hv_trace.h"
+
+/*
+ * Timeout for services such as KVP and fcopy.
+ */
+#define HV_UTIL_TIMEOUT 30
+
+/*
+ * Timeout for guest-host handshake for services.
+ */
+#define HV_UTIL_NEGO_TIMEOUT 55
+
+/* Define synthetic interrupt controller flag constants. */
+#define HV_EVENT_FLAGS_COUNT		(256 * 8)
+#define HV_EVENT_FLAGS_LONG_COUNT	(256 / sizeof(unsigned long))
+
+/*
+ * Timer configuration register.
+ */
+union hv_timer_config {
+	u64 as_uint64;
+	struct {
+		u64 enable:1;
+		u64 periodic:1;
+		u64 lazy:1;
+		u64 auto_enable:1;
+		u64 apic_vector:8;
+		u64 direct_mode:1;
+		u64 reserved_z0:3;
+		u64 sintx:4;
+		u64 reserved_z1:44;
+	};
+};
+
+
+/* Define the synthetic interrupt controller event flags format. */
+union hv_synic_event_flags {
+	unsigned long flags[HV_EVENT_FLAGS_LONG_COUNT];
+};
+
+/* Define SynIC control register. */
+union hv_synic_scontrol {
+	u64 as_uint64;
+	struct {
+		u64 enable:1;
+		u64 reserved:63;
+	};
+};
+
+/* Define synthetic interrupt source. */
+union hv_synic_sint {
+	u64 as_uint64;
+	struct {
+		u64 vector:8;
+		u64 reserved1:8;
+		u64 masked:1;
+		u64 auto_eoi:1;
+		u64 reserved2:46;
+	};
+};
+
+/* Define the format of the SIMP register */
+union hv_synic_simp {
+	u64 as_uint64;
+	struct {
+		u64 simp_enabled:1;
+		u64 preserved:11;
+		u64 base_simp_gpa:52;
+	};
+};
+
+/* Define the format of the SIEFP register */
+union hv_synic_siefp {
+	u64 as_uint64;
+	struct {
+		u64 siefp_enabled:1;
+		u64 preserved:11;
+		u64 base_siefp_gpa:52;
+	};
+};
+
+/* Definitions for the monitored notification facility */
+union hv_monitor_trigger_group {
+	u64 as_uint64;
+	struct {
+		u32 pending;
+		u32 armed;
+	};
+};
+
+struct hv_monitor_parameter {
+	union hv_connection_id connectionid;
+	u16 flagnumber;
+	u16 rsvdz;
+};
+
+union hv_monitor_trigger_state {
+	u32 asu32;
+
+	struct {
+		u32 group_enable:4;
+		u32 rsvdz:28;
+	};
+};
+
+/* struct hv_monitor_page Layout */
+/* ------------------------------------------------------ */
+/* | 0   | TriggerState (4 bytes) | Rsvd1 (4 bytes)     | */
+/* | 8   | TriggerGroup[0]                              | */
+/* | 10  | TriggerGroup[1]                              | */
+/* | 18  | TriggerGroup[2]                              | */
+/* | 20  | TriggerGroup[3]                              | */
+/* | 28  | Rsvd2[0]                                     | */
+/* | 30  | Rsvd2[1]                                     | */
+/* | 38  | Rsvd2[2]                                     | */
+/* | 40  | NextCheckTime[0][0]    | NextCheckTime[0][1] | */
+/* | ...                                                | */
+/* | 240 | Latency[0][0..3]                             | */
+/* | 340 | Rsvz3[0]                                     | */
+/* | 440 | Parameter[0][0]                              | */
+/* | 448 | Parameter[0][1]                              | */
+/* | ...                                                | */
+/* | 840 | Rsvd4[0]                                     | */
+/* ------------------------------------------------------ */
+struct hv_monitor_page {
+	union hv_monitor_trigger_state trigger_state;
+	u32 rsvdz1;
+
+	union hv_monitor_trigger_group trigger_group[4];
+	u64 rsvdz2[3];
+
+	s32 next_checktime[4][32];
+
+	u16 latency[4][32];
+	u64 rsvdz3[32];
+
+	struct hv_monitor_parameter parameter[4][32];
+
+	u8 rsvdz4[1984];
+};
+
+#define HV_HYPERCALL_PARAM_ALIGN	sizeof(u64)
+
+/* Definition of the hv_post_message hypercall input structure. */
+struct hv_input_post_message {
+	union hv_connection_id connectionid;
+	u32 reserved;
+	u32 message_type;
+	u32 payload_size;
+	u64 payload[HV_MESSAGE_PAYLOAD_QWORD_COUNT];
+};
+
+
+enum {
+	VMBUS_MESSAGE_CONNECTION_ID	= 1,
+	VMBUS_MESSAGE_CONNECTION_ID_4	= 4,
+	VMBUS_MESSAGE_PORT_ID		= 1,
+	VMBUS_EVENT_CONNECTION_ID	= 2,
+	VMBUS_EVENT_PORT_ID		= 2,
+	VMBUS_MONITOR_CONNECTION_ID	= 3,
+	VMBUS_MONITOR_PORT_ID		= 3,
+	VMBUS_MESSAGE_SINT		= 2,
+};
+
+/*
+ * Per cpu state for channel handling
+ */
+struct hv_per_cpu_context {
+	void *synic_message_page;
+	void *synic_event_page;
+	/*
+	 * buffer to post messages to the host.
+	 */
+	void *post_msg_page;
+
+	/*
+	 * Starting with win8, we can take channel interrupts on any CPU;
+	 * we will manage the tasklet that handles events messages on a per CPU
+	 * basis.
+	 */
+	struct tasklet_struct msg_dpc;
+
+	/*
+	 * To optimize the mapping of relid to channel, maintain
+	 * per-cpu list of the channels based on their CPU affinity.
+	 */
+	struct list_head chan_list;
+	struct clock_event_device *clk_evt;
+};
+
+struct hv_context {
+	/* We only support running on top of Hyper-V
+	 * So at this point this really can only contain the Hyper-V ID
+	 */
+	u64 guestid;
+
+	void *tsc_page;
+
+	bool synic_initialized;
+
+	struct hv_per_cpu_context __percpu *cpu_context;
+
+	/*
+	 * To manage allocations in a NUMA node.
+	 * Array indexed by numa node ID.
+	 */
+	struct cpumask *hv_numa_map;
+};
+
+extern struct hv_context hv_context;
+
+/* Hv Interface */
+
+extern int hv_init(void);
+
+extern int hv_post_message(union hv_connection_id connection_id,
+			 enum hv_message_type message_type,
+			 void *payload, size_t payload_size);
+
+extern int hv_synic_alloc(void);
+
+extern void hv_synic_free(void);
+
+extern int hv_synic_init(unsigned int cpu);
+
+extern int hv_synic_cleanup(unsigned int cpu);
+
+extern void hv_synic_clockevents_cleanup(void);
+
+/* Interface */
+
+
+int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
+		       struct page *pages, u32 pagecnt);
+
+void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
+
+int hv_ringbuffer_write(struct vmbus_channel *channel,
+			const struct kvec *kv_list, u32 kv_count);
+
+int hv_ringbuffer_read(struct vmbus_channel *channel,
+		       void *buffer, u32 buflen, u32 *buffer_actual_len,
+		       u64 *requestid, bool raw);
+
+/*
+ * Maximum channels is determined by the size of the interrupt page
+ * which is PAGE_SIZE. 1/2 of PAGE_SIZE is for send endpoint interrupt
+ * and the other is receive endpoint interrupt
+ */
+#define MAX_NUM_CHANNELS	((PAGE_SIZE >> 1) << 3)	/* 16348 channels */
+
+/* The value here must be in multiple of 32 */
+/* TODO: Need to make this configurable */
+#define MAX_NUM_CHANNELS_SUPPORTED	256
+
+
+enum vmbus_connect_state {
+	DISCONNECTED,
+	CONNECTING,
+	CONNECTED,
+	DISCONNECTING
+};
+
+#define MAX_SIZE_CHANNEL_MESSAGE	HV_MESSAGE_PAYLOAD_BYTE_COUNT
+
+struct vmbus_connection {
+	/*
+	 * CPU on which the initial host contact was made.
+	 */
+	int connect_cpu;
+
+	u32 msg_conn_id;
+
+	atomic_t offer_in_progress;
+
+	enum vmbus_connect_state conn_state;
+
+	atomic_t next_gpadl_handle;
+
+	struct completion  unload_event;
+	/*
+	 * Represents channel interrupts. Each bit position represents a
+	 * channel.  When a channel sends an interrupt via VMBUS, it finds its
+	 * bit in the sendInterruptPage, set it and calls Hv to generate a port
+	 * event. The other end receives the port event and parse the
+	 * recvInterruptPage to see which bit is set
+	 */
+	void *int_page;
+	void *send_int_page;
+	void *recv_int_page;
+
+	/*
+	 * 2 pages - 1st page for parent->child notification and 2nd
+	 * is child->parent notification
+	 */
+	struct hv_monitor_page *monitor_pages[2];
+	struct list_head chn_msg_list;
+	spinlock_t channelmsg_lock;
+
+	/* List of channels */
+	struct list_head chn_list;
+	struct mutex channel_mutex;
+
+	/*
+	 * An offer message is handled first on the work_queue, and then
+	 * is further handled on handle_primary_chan_wq or
+	 * handle_sub_chan_wq.
+	 */
+	struct workqueue_struct *work_queue;
+	struct workqueue_struct *handle_primary_chan_wq;
+	struct workqueue_struct *handle_sub_chan_wq;
+};
+
+
+struct vmbus_msginfo {
+	/* Bookkeeping stuff */
+	struct list_head msglist_entry;
+
+	/* The message itself */
+	unsigned char msg[0];
+};
+
+
+extern struct vmbus_connection vmbus_connection;
+
+static inline void vmbus_send_interrupt(u32 relid)
+{
+	sync_set_bit(relid, vmbus_connection.send_int_page);
+}
+
+enum vmbus_message_handler_type {
+	/* The related handler can sleep. */
+	VMHT_BLOCKING = 0,
+
+	/* The related handler must NOT sleep. */
+	VMHT_NON_BLOCKING = 1,
+};
+
+struct vmbus_channel_message_table_entry {
+	enum vmbus_channel_message_type message_type;
+	enum vmbus_message_handler_type handler_type;
+	void (*message_handler)(struct vmbus_channel_message_header *msg);
+};
+
+extern const struct vmbus_channel_message_table_entry
+	channel_message_table[CHANNELMSG_COUNT];
+
+
+/* General vmbus interface */
+
+struct hv_device *vmbus_device_create(const uuid_le *type,
+				      const uuid_le *instance,
+				      struct vmbus_channel *channel);
+
+int vmbus_device_register(struct hv_device *child_device_obj);
+void vmbus_device_unregister(struct hv_device *device_obj);
+int vmbus_add_channel_kobj(struct hv_device *device_obj,
+			   struct vmbus_channel *channel);
+
+struct vmbus_channel *relid2channel(u32 relid);
+
+void vmbus_free_channels(void);
+
+/* Connection interface */
+
+int vmbus_connect(void);
+void vmbus_disconnect(void);
+
+int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
+
+void vmbus_on_event(unsigned long data);
+void vmbus_on_msg_dpc(unsigned long data);
+
+int hv_kvp_init(struct hv_util_service *srv);
+void hv_kvp_deinit(void);
+void hv_kvp_onchannelcallback(void *context);
+
+int hv_vss_init(struct hv_util_service *srv);
+void hv_vss_deinit(void);
+void hv_vss_onchannelcallback(void *context);
+
+int hv_fcopy_init(struct hv_util_service *srv);
+void hv_fcopy_deinit(void);
+void hv_fcopy_onchannelcallback(void *context);
+void vmbus_initiate_unload(bool crash);
+
+static inline void hv_poll_channel(struct vmbus_channel *channel,
+				   void (*cb)(void *))
+{
+	if (!channel)
+		return;
+
+	if (in_interrupt() && (channel->target_cpu == smp_processor_id())) {
+		cb(channel);
+		return;
+	}
+	smp_call_function_single(channel->target_cpu, cb, channel, true);
+}
+
+enum hvutil_device_state {
+	HVUTIL_DEVICE_INIT = 0,  /* driver is loaded, waiting for userspace */
+	HVUTIL_READY,            /* userspace is registered */
+	HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
+	HVUTIL_USERSPACE_REQ,    /* request to userspace was sent */
+	HVUTIL_USERSPACE_RECV,   /* reply from userspace was received */
+	HVUTIL_DEVICE_DYING,     /* driver unload is in progress */
+};
+
+#endif /* _HYPERV_VMBUS_H */