Initial import

6 files changed, 4656 insertions, 0 deletions

diff --git a/drivers/net/hyperv/Kconfig b/drivers/net/hyperv/Kconfig
new file mode 100644
index 000000000..936968d23
--- /dev/null
+++ b/drivers/net/hyperv/Kconfig
@@ -0,0 +1,5 @@
+config HYPERV_NET
+	tristate "Microsoft Hyper-V virtual network driver"
+	depends on HYPERV
+	help
+	  Select this option to enable the Hyper-V virtual network driver.
diff --git a/drivers/net/hyperv/Makefile b/drivers/net/hyperv/Makefile
new file mode 100644
index 000000000..c8a668271
--- /dev/null
+++ b/drivers/net/hyperv/Makefile
@@ -0,0 +1,3 @@
+obj-$(CONFIG_HYPERV_NET) += hv_netvsc.o
+
+hv_netvsc-y := netvsc_drv.o netvsc.o rndis_filter.o
diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
new file mode 100644
index 000000000..41071d32b
--- /dev/null
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -0,0 +1,1221 @@
+/*
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *   K. Y. Srinivasan <kys@microsoft.com>
+ *
+ */
+
+#ifndef _HYPERV_NET_H
+#define _HYPERV_NET_H
+
+#include <linux/list.h>
+#include <linux/hyperv.h>
+#include <linux/rndis.h>
+
+/* RSS related */
+#define OID_GEN_RECEIVE_SCALE_CAPABILITIES 0x00010203  /* query only */
+#define OID_GEN_RECEIVE_SCALE_PARAMETERS 0x00010204  /* query and set */
+
+#define NDIS_OBJECT_TYPE_RSS_CAPABILITIES 0x88
+#define NDIS_OBJECT_TYPE_RSS_PARAMETERS 0x89
+
+#define NDIS_RECEIVE_SCALE_CAPABILITIES_REVISION_2 2
+#define NDIS_RECEIVE_SCALE_PARAMETERS_REVISION_2 2
+
+struct ndis_obj_header {
+	u8 type;
+	u8 rev;
+	u16 size;
+} __packed;
+
+/* ndis_recv_scale_cap/cap_flag */
+#define NDIS_RSS_CAPS_MESSAGE_SIGNALED_INTERRUPTS 0x01000000
+#define NDIS_RSS_CAPS_CLASSIFICATION_AT_ISR       0x02000000
+#define NDIS_RSS_CAPS_CLASSIFICATION_AT_DPC       0x04000000
+#define NDIS_RSS_CAPS_USING_MSI_X                 0x08000000
+#define NDIS_RSS_CAPS_RSS_AVAILABLE_ON_PORTS      0x10000000
+#define NDIS_RSS_CAPS_SUPPORTS_MSI_X              0x20000000
+#define NDIS_RSS_CAPS_HASH_TYPE_TCP_IPV4          0x00000100
+#define NDIS_RSS_CAPS_HASH_TYPE_TCP_IPV6          0x00000200
+#define NDIS_RSS_CAPS_HASH_TYPE_TCP_IPV6_EX       0x00000400
+
+struct ndis_recv_scale_cap { /* NDIS_RECEIVE_SCALE_CAPABILITIES */
+	struct ndis_obj_header hdr;
+	u32 cap_flag;
+	u32 num_int_msg;
+	u32 num_recv_que;
+	u16 num_indirect_tabent;
+} __packed;
+
+
+/* ndis_recv_scale_param flags */
+#define NDIS_RSS_PARAM_FLAG_BASE_CPU_UNCHANGED     0x0001
+#define NDIS_RSS_PARAM_FLAG_HASH_INFO_UNCHANGED    0x0002
+#define NDIS_RSS_PARAM_FLAG_ITABLE_UNCHANGED       0x0004
+#define NDIS_RSS_PARAM_FLAG_HASH_KEY_UNCHANGED     0x0008
+#define NDIS_RSS_PARAM_FLAG_DISABLE_RSS            0x0010
+
+/* Hash info bits */
+#define NDIS_HASH_FUNC_TOEPLITZ 0x00000001
+#define NDIS_HASH_IPV4          0x00000100
+#define NDIS_HASH_TCP_IPV4      0x00000200
+#define NDIS_HASH_IPV6          0x00000400
+#define NDIS_HASH_IPV6_EX       0x00000800
+#define NDIS_HASH_TCP_IPV6      0x00001000
+#define NDIS_HASH_TCP_IPV6_EX   0x00002000
+
+#define NDIS_RSS_INDIRECTION_TABLE_MAX_SIZE_REVISION_2 (128 * 4)
+#define NDIS_RSS_HASH_SECRET_KEY_MAX_SIZE_REVISION_2   40
+
+#define ITAB_NUM 128
+#define HASH_KEYLEN NDIS_RSS_HASH_SECRET_KEY_MAX_SIZE_REVISION_2
+extern u8 netvsc_hash_key[];
+
+struct ndis_recv_scale_param { /* NDIS_RECEIVE_SCALE_PARAMETERS */
+	struct ndis_obj_header hdr;
+
+	/* Qualifies the rest of the information */
+	u16 flag;
+
+	/* The base CPU number to do receive processing. not used */
+	u16 base_cpu_number;
+
+	/* This describes the hash function and type being enabled */
+	u32 hashinfo;
+
+	/* The size of indirection table array */
+	u16 indirect_tabsize;
+
+	/* The offset of the indirection table from the beginning of this
+	 * structure
+	 */
+	u32 indirect_taboffset;
+
+	/* The size of the hash secret key */
+	u16 hashkey_size;
+
+	/* The offset of the secret key from the beginning of this structure */
+	u32 kashkey_offset;
+
+	u32 processor_masks_offset;
+	u32 num_processor_masks;
+	u32 processor_masks_entry_size;
+};
+
+/* Fwd declaration */
+struct ndis_tcp_ip_checksum_info;
+
+/*
+ * Represent netvsc packet which contains 1 RNDIS and 1 ethernet frame
+ * within the RNDIS
+ */
+struct hv_netvsc_packet {
+	/* Bookkeeping stuff */
+	u32 status;
+
+	bool is_data_pkt;
+	bool xmit_more; /* from skb */
+	bool cp_partial; /* partial copy into send buffer */
+
+	u16 vlan_tci;
+
+	u16 q_idx;
+	struct vmbus_channel *channel;
+
+	u64 send_completion_tid;
+	void *send_completion_ctx;
+	void (*send_completion)(void *context);
+
+	u32 send_buf_index;
+
+	/* This points to the memory after page_buf */
+	struct rndis_message *rndis_msg;
+
+	u32 rmsg_size; /* RNDIS header and PPI size */
+	u32 rmsg_pgcnt; /* page count of RNDIS header and PPI */
+
+	u32 total_data_buflen;
+	/* Points to the send/receive buffer where the ethernet frame is */
+	void *data;
+	u32 page_buf_cnt;
+	struct hv_page_buffer *page_buf;
+};
+
+struct netvsc_device_info {
+	unsigned char mac_adr[ETH_ALEN];
+	bool link_state;	/* 0 - link up, 1 - link down */
+	int  ring_size;
+};
+
+enum rndis_device_state {
+	RNDIS_DEV_UNINITIALIZED = 0,
+	RNDIS_DEV_INITIALIZING,
+	RNDIS_DEV_INITIALIZED,
+	RNDIS_DEV_DATAINITIALIZED,
+};
+
+struct rndis_device {
+	struct netvsc_device *net_dev;
+
+	enum rndis_device_state state;
+	bool link_state;
+	bool link_change;
+	atomic_t new_req_id;
+
+	spinlock_t request_lock;
+	struct list_head req_list;
+
+	unsigned char hw_mac_adr[ETH_ALEN];
+};
+
+
+/* Interface */
+int netvsc_device_add(struct hv_device *device, void *additional_info);
+int netvsc_device_remove(struct hv_device *device);
+int netvsc_send(struct hv_device *device,
+		struct hv_netvsc_packet *packet);
+void netvsc_linkstatus_callback(struct hv_device *device_obj,
+				struct rndis_message *resp);
+void netvsc_xmit_completion(void *context);
+int netvsc_recv_callback(struct hv_device *device_obj,
+			struct hv_netvsc_packet *packet,
+			struct ndis_tcp_ip_checksum_info *csum_info);
+void netvsc_channel_cb(void *context);
+int rndis_filter_open(struct hv_device *dev);
+int rndis_filter_close(struct hv_device *dev);
+int rndis_filter_device_add(struct hv_device *dev,
+			void *additional_info);
+void rndis_filter_device_remove(struct hv_device *dev);
+int rndis_filter_receive(struct hv_device *dev,
+			struct hv_netvsc_packet *pkt);
+
+int rndis_filter_set_packet_filter(struct rndis_device *dev, u32 new_filter);
+int rndis_filter_set_device_mac(struct hv_device *hdev, char *mac);
+
+
+#define NVSP_INVALID_PROTOCOL_VERSION	((u32)0xFFFFFFFF)
+
+#define NVSP_PROTOCOL_VERSION_1		2
+#define NVSP_PROTOCOL_VERSION_2		0x30002
+#define NVSP_PROTOCOL_VERSION_4		0x40000
+#define NVSP_PROTOCOL_VERSION_5		0x50000
+
+enum {
+	NVSP_MSG_TYPE_NONE = 0,
+
+	/* Init Messages */
+	NVSP_MSG_TYPE_INIT			= 1,
+	NVSP_MSG_TYPE_INIT_COMPLETE		= 2,
+
+	NVSP_VERSION_MSG_START			= 100,
+
+	/* Version 1 Messages */
+	NVSP_MSG1_TYPE_SEND_NDIS_VER		= NVSP_VERSION_MSG_START,
+
+	NVSP_MSG1_TYPE_SEND_RECV_BUF,
+	NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE,
+	NVSP_MSG1_TYPE_REVOKE_RECV_BUF,
+
+	NVSP_MSG1_TYPE_SEND_SEND_BUF,
+	NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE,
+	NVSP_MSG1_TYPE_REVOKE_SEND_BUF,
+
+	NVSP_MSG1_TYPE_SEND_RNDIS_PKT,
+	NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE,
+
+	/* Version 2 messages */
+	NVSP_MSG2_TYPE_SEND_CHIMNEY_DELEGATED_BUF,
+	NVSP_MSG2_TYPE_SEND_CHIMNEY_DELEGATED_BUF_COMP,
+	NVSP_MSG2_TYPE_REVOKE_CHIMNEY_DELEGATED_BUF,
+
+	NVSP_MSG2_TYPE_RESUME_CHIMNEY_RX_INDICATION,
+
+	NVSP_MSG2_TYPE_TERMINATE_CHIMNEY,
+	NVSP_MSG2_TYPE_TERMINATE_CHIMNEY_COMP,
+
+	NVSP_MSG2_TYPE_INDICATE_CHIMNEY_EVENT,
+
+	NVSP_MSG2_TYPE_SEND_CHIMNEY_PKT,
+	NVSP_MSG2_TYPE_SEND_CHIMNEY_PKT_COMP,
+
+	NVSP_MSG2_TYPE_POST_CHIMNEY_RECV_REQ,
+	NVSP_MSG2_TYPE_POST_CHIMNEY_RECV_REQ_COMP,
+
+	NVSP_MSG2_TYPE_ALLOC_RXBUF,
+	NVSP_MSG2_TYPE_ALLOC_RXBUF_COMP,
+
+	NVSP_MSG2_TYPE_FREE_RXBUF,
+
+	NVSP_MSG2_TYPE_SEND_VMQ_RNDIS_PKT,
+	NVSP_MSG2_TYPE_SEND_VMQ_RNDIS_PKT_COMP,
+
+	NVSP_MSG2_TYPE_SEND_NDIS_CONFIG,
+
+	NVSP_MSG2_TYPE_ALLOC_CHIMNEY_HANDLE,
+	NVSP_MSG2_TYPE_ALLOC_CHIMNEY_HANDLE_COMP,
+
+	NVSP_MSG2_MAX = NVSP_MSG2_TYPE_ALLOC_CHIMNEY_HANDLE_COMP,
+
+	/* Version 4 messages */
+	NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION,
+	NVSP_MSG4_TYPE_SWITCH_DATA_PATH,
+	NVSP_MSG4_TYPE_UPLINK_CONNECT_STATE_DEPRECATED,
+
+	NVSP_MSG4_MAX = NVSP_MSG4_TYPE_UPLINK_CONNECT_STATE_DEPRECATED,
+
+	/* Version 5 messages */
+	NVSP_MSG5_TYPE_OID_QUERY_EX,
+	NVSP_MSG5_TYPE_OID_QUERY_EX_COMP,
+	NVSP_MSG5_TYPE_SUBCHANNEL,
+	NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE,
+
+	NVSP_MSG5_MAX = NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE,
+};
+
+enum {
+	NVSP_STAT_NONE = 0,
+	NVSP_STAT_SUCCESS,
+	NVSP_STAT_FAIL,
+	NVSP_STAT_PROTOCOL_TOO_NEW,
+	NVSP_STAT_PROTOCOL_TOO_OLD,
+	NVSP_STAT_INVALID_RNDIS_PKT,
+	NVSP_STAT_BUSY,
+	NVSP_STAT_PROTOCOL_UNSUPPORTED,
+	NVSP_STAT_MAX,
+};
+
+struct nvsp_message_header {
+	u32 msg_type;
+};
+
+/* Init Messages */
+
+/*
+ * This message is used by the VSC to initialize the channel after the channels
+ * has been opened. This message should never include anything other then
+ * versioning (i.e. this message will be the same for ever).
+ */
+struct nvsp_message_init {
+	u32 min_protocol_ver;
+	u32 max_protocol_ver;
+} __packed;
+
+/*
+ * This message is used by the VSP to complete the initialization of the
+ * channel. This message should never include anything other then versioning
+ * (i.e. this message will be the same for ever).
+ */
+struct nvsp_message_init_complete {
+	u32 negotiated_protocol_ver;
+	u32 max_mdl_chain_len;
+	u32 status;
+} __packed;
+
+union nvsp_message_init_uber {
+	struct nvsp_message_init init;
+	struct nvsp_message_init_complete init_complete;
+} __packed;
+
+/* Version 1 Messages */
+
+/*
+ * This message is used by the VSC to send the NDIS version to the VSP. The VSP
+ * can use this information when handling OIDs sent by the VSC.
+ */
+struct nvsp_1_message_send_ndis_version {
+	u32 ndis_major_ver;
+	u32 ndis_minor_ver;
+} __packed;
+
+/*
+ * This message is used by the VSC to send a receive buffer to the VSP. The VSP
+ * can then use the receive buffer to send data to the VSC.
+ */
+struct nvsp_1_message_send_receive_buffer {
+	u32 gpadl_handle;
+	u16 id;
+} __packed;
+
+struct nvsp_1_receive_buffer_section {
+	u32 offset;
+	u32 sub_alloc_size;
+	u32 num_sub_allocs;
+	u32 end_offset;
+} __packed;
+
+/*
+ * This message is used by the VSP to acknowledge a receive buffer send by the
+ * VSC. This message must be sent by the VSP before the VSP uses the receive
+ * buffer.
+ */
+struct nvsp_1_message_send_receive_buffer_complete {
+	u32 status;
+	u32 num_sections;
+
+	/*
+	 * The receive buffer is split into two parts, a large suballocation
+	 * section and a small suballocation section. These sections are then
+	 * suballocated by a certain size.
+	 */
+
+	/*
+	 * For example, the following break up of the receive buffer has 6
+	 * large suballocations and 10 small suballocations.
+	 */
+
+	/*
+	 * |            Large Section          |  |   Small Section   |
+	 * ------------------------------------------------------------
+	 * |     |     |     |     |     |     |  | | | | | | | | | | |
+	 * |                                      |
+	 *  LargeOffset                            SmallOffset
+	 */
+
+	struct nvsp_1_receive_buffer_section sections[1];
+} __packed;
+
+/*
+ * This message is sent by the VSC to revoke the receive buffer.  After the VSP
+ * completes this transaction, the vsp should never use the receive buffer
+ * again.
+ */
+struct nvsp_1_message_revoke_receive_buffer {
+	u16 id;
+};
+
+/*
+ * This message is used by the VSC to send a send buffer to the VSP. The VSC
+ * can then use the send buffer to send data to the VSP.
+ */
+struct nvsp_1_message_send_send_buffer {
+	u32 gpadl_handle;
+	u16 id;
+} __packed;
+
+/*
+ * This message is used by the VSP to acknowledge a send buffer sent by the
+ * VSC. This message must be sent by the VSP before the VSP uses the sent
+ * buffer.
+ */
+struct nvsp_1_message_send_send_buffer_complete {
+	u32 status;
+
+	/*
+	 * The VSC gets to choose the size of the send buffer and the VSP gets
+	 * to choose the sections size of the buffer.  This was done to enable
+	 * dynamic reconfigurations when the cost of GPA-direct buffers
+	 * decreases.
+	 */
+	u32 section_size;
+} __packed;
+
+/*
+ * This message is sent by the VSC to revoke the send buffer.  After the VSP
+ * completes this transaction, the vsp should never use the send buffer again.
+ */
+struct nvsp_1_message_revoke_send_buffer {
+	u16 id;
+};
+
+/*
+ * This message is used by both the VSP and the VSC to send a RNDIS message to
+ * the opposite channel endpoint.
+ */
+struct nvsp_1_message_send_rndis_packet {
+	/*
+	 * This field is specified by RNIDS. They assume there's two different
+	 * channels of communication. However, the Network VSP only has one.
+	 * Therefore, the channel travels with the RNDIS packet.
+	 */
+	u32 channel_type;
+
+	/*
+	 * This field is used to send part or all of the data through a send
+	 * buffer. This values specifies an index into the send buffer. If the
+	 * index is 0xFFFFFFFF, then the send buffer is not being used and all
+	 * of the data was sent through other VMBus mechanisms.
+	 */
+	u32 send_buf_section_index;
+	u32 send_buf_section_size;
+} __packed;
+
+/*
+ * This message is used by both the VSP and the VSC to complete a RNDIS message
+ * to the opposite channel endpoint. At this point, the initiator of this
+ * message cannot use any resources associated with the original RNDIS packet.
+ */
+struct nvsp_1_message_send_rndis_packet_complete {
+	u32 status;
+};
+
+union nvsp_1_message_uber {
+	struct nvsp_1_message_send_ndis_version send_ndis_ver;
+
+	struct nvsp_1_message_send_receive_buffer send_recv_buf;
+	struct nvsp_1_message_send_receive_buffer_complete
+						send_recv_buf_complete;
+	struct nvsp_1_message_revoke_receive_buffer revoke_recv_buf;
+
+	struct nvsp_1_message_send_send_buffer send_send_buf;
+	struct nvsp_1_message_send_send_buffer_complete send_send_buf_complete;
+	struct nvsp_1_message_revoke_send_buffer revoke_send_buf;
+
+	struct nvsp_1_message_send_rndis_packet send_rndis_pkt;
+	struct nvsp_1_message_send_rndis_packet_complete
+						send_rndis_pkt_complete;
+} __packed;
+
+
+/*
+ * Network VSP protocol version 2 messages:
+ */
+struct nvsp_2_vsc_capability {
+	union {
+		u64 data;
+		struct {
+			u64 vmq:1;
+			u64 chimney:1;
+			u64 sriov:1;
+			u64 ieee8021q:1;
+			u64 correlation_id:1;
+		};
+	};
+} __packed;
+
+struct nvsp_2_send_ndis_config {
+	u32 mtu;
+	u32 reserved;
+	struct nvsp_2_vsc_capability capability;
+} __packed;
+
+/* Allocate receive buffer */
+struct nvsp_2_alloc_rxbuf {
+	/* Allocation ID to match the allocation request and response */
+	u32 alloc_id;
+
+	/* Length of the VM shared memory receive buffer that needs to
+	 * be allocated
+	 */
+	u32 len;
+} __packed;
+
+/* Allocate receive buffer complete */
+struct nvsp_2_alloc_rxbuf_comp {
+	/* The NDIS_STATUS code for buffer allocation */
+	u32 status;
+
+	u32 alloc_id;
+
+	/* GPADL handle for the allocated receive buffer */
+	u32 gpadl_handle;
+
+	/* Receive buffer ID */
+	u64 recv_buf_id;
+} __packed;
+
+struct nvsp_2_free_rxbuf {
+	u64 recv_buf_id;
+} __packed;
+
+union nvsp_2_message_uber {
+	struct nvsp_2_send_ndis_config send_ndis_config;
+	struct nvsp_2_alloc_rxbuf alloc_rxbuf;
+	struct nvsp_2_alloc_rxbuf_comp alloc_rxbuf_comp;
+	struct nvsp_2_free_rxbuf free_rxbuf;
+} __packed;
+
+enum nvsp_subchannel_operation {
+	NVSP_SUBCHANNEL_NONE = 0,
+	NVSP_SUBCHANNEL_ALLOCATE,
+	NVSP_SUBCHANNEL_MAX
+};
+
+struct nvsp_5_subchannel_request {
+	u32 op;
+	u32 num_subchannels;
+} __packed;
+
+struct nvsp_5_subchannel_complete {
+	u32 status;
+	u32 num_subchannels; /* Actual number of subchannels allocated */
+} __packed;
+
+struct nvsp_5_send_indirect_table {
+	/* The number of entries in the send indirection table */
+	u32 count;
+
+	/* The offset of the send indireciton table from top of this struct.
+	 * The send indirection table tells which channel to put the send
+	 * traffic on. Each entry is a channel number.
+	 */
+	u32 offset;
+} __packed;
+
+union nvsp_5_message_uber {
+	struct nvsp_5_subchannel_request subchn_req;
+	struct nvsp_5_subchannel_complete subchn_comp;
+	struct nvsp_5_send_indirect_table send_table;
+} __packed;
+
+union nvsp_all_messages {
+	union nvsp_message_init_uber init_msg;
+	union nvsp_1_message_uber v1_msg;
+	union nvsp_2_message_uber v2_msg;
+	union nvsp_5_message_uber v5_msg;
+} __packed;
+
+/* ALL Messages */
+struct nvsp_message {
+	struct nvsp_message_header hdr;
+	union nvsp_all_messages msg;
+} __packed;
+
+
+#define NETVSC_MTU 65536
+
+#define NETVSC_RECEIVE_BUFFER_SIZE		(1024*1024*16)	/* 16MB */
+#define NETVSC_RECEIVE_BUFFER_SIZE_LEGACY	(1024*1024*15)  /* 15MB */
+#define NETVSC_SEND_BUFFER_SIZE			(1024 * 1024 * 15)   /* 15MB */
+#define NETVSC_INVALID_INDEX			-1
+
+
+#define NETVSC_RECEIVE_BUFFER_ID		0xcafe
+#define NETVSC_SEND_BUFFER_ID			0
+
+#define NETVSC_PACKET_SIZE                      4096
+
+#define VRSS_SEND_TAB_SIZE 16
+
+#define RNDIS_MAX_PKT_DEFAULT 8
+#define RNDIS_PKT_ALIGN_DEFAULT 8
+
+struct multi_send_data {
+	spinlock_t lock; /* protect struct multi_send_data */
+	struct hv_netvsc_packet *pkt; /* netvsc pkt pending */
+	u32 count; /* counter of batched packets */
+};
+
+/* The context of the netvsc device  */
+struct net_device_context {
+	/* point back to our device context */
+	struct hv_device *device_ctx;
+	struct delayed_work dwork;
+	struct work_struct work;
+	u32 msg_enable; /* debug level */
+};
+
+/* Per netvsc device */
+struct netvsc_device {
+	struct hv_device *dev;
+
+	u32 nvsp_version;
+
+	atomic_t num_outstanding_sends;
+	wait_queue_head_t wait_drain;
+	bool start_remove;
+	bool destroy;
+
+	/* Receive buffer allocated by us but manages by NetVSP */
+	void *recv_buf;
+	u32 recv_buf_size;
+	u32 recv_buf_gpadl_handle;
+	u32 recv_section_cnt;
+	struct nvsp_1_receive_buffer_section *recv_section;
+
+	/* Send buffer allocated by us */
+	void *send_buf;
+	u32 send_buf_size;
+	u32 send_buf_gpadl_handle;
+	u32 send_section_cnt;
+	u32 send_section_size;
+	unsigned long *send_section_map;
+	int map_words;
+
+	/* Used for NetVSP initialization protocol */
+	struct completion channel_init_wait;
+	struct nvsp_message channel_init_pkt;
+
+	struct nvsp_message revoke_packet;
+	/* unsigned char HwMacAddr[HW_MACADDR_LEN]; */
+
+	struct net_device *ndev;
+
+	struct vmbus_channel *chn_table[NR_CPUS];
+	u32 send_table[VRSS_SEND_TAB_SIZE];
+	u32 max_chn;
+	u32 num_chn;
+	atomic_t queue_sends[NR_CPUS];
+
+	/* Holds rndis device info */
+	void *extension;
+
+	int ring_size;
+
+	/* The primary channel callback buffer */
+	unsigned char *cb_buffer;
+	/* The sub channel callback buffer */
+	unsigned char *sub_cb_buf;
+
+	struct multi_send_data msd[NR_CPUS];
+	u32 max_pkt; /* max number of pkt in one send, e.g. 8 */
+	u32 pkt_align; /* alignment bytes, e.g. 8 */
+
+	/* The net device context */
+	struct net_device_context *nd_ctx;
+};
+
+/* NdisInitialize message */
+struct rndis_initialize_request {
+	u32 req_id;
+	u32 major_ver;
+	u32 minor_ver;
+	u32 max_xfer_size;
+};
+
+/* Response to NdisInitialize */
+struct rndis_initialize_complete {
+	u32 req_id;
+	u32 status;
+	u32 major_ver;
+	u32 minor_ver;
+	u32 dev_flags;
+	u32 medium;
+	u32 max_pkt_per_msg;
+	u32 max_xfer_size;
+	u32 pkt_alignment_factor;
+	u32 af_list_offset;
+	u32 af_list_size;
+};
+
+/* Call manager devices only: Information about an address family */
+/* supported by the device is appended to the response to NdisInitialize. */
+struct rndis_co_address_family {
+	u32 address_family;
+	u32 major_ver;
+	u32 minor_ver;
+};
+
+/* NdisHalt message */
+struct rndis_halt_request {
+	u32 req_id;
+};
+
+/* NdisQueryRequest message */
+struct rndis_query_request {
+	u32 req_id;
+	u32 oid;
+	u32 info_buflen;
+	u32 info_buf_offset;
+	u32 dev_vc_handle;
+};
+
+/* Response to NdisQueryRequest */
+struct rndis_query_complete {
+	u32 req_id;
+	u32 status;
+	u32 info_buflen;
+	u32 info_buf_offset;
+};
+
+/* NdisSetRequest message */
+struct rndis_set_request {
+	u32 req_id;
+	u32 oid;
+	u32 info_buflen;
+	u32 info_buf_offset;
+	u32 dev_vc_handle;
+};
+
+/* Response to NdisSetRequest */
+struct rndis_set_complete {
+	u32 req_id;
+	u32 status;
+};
+
+/* NdisReset message */
+struct rndis_reset_request {
+	u32 reserved;
+};
+
+/* Response to NdisReset */
+struct rndis_reset_complete {
+	u32 status;
+	u32 addressing_reset;
+};
+
+/* NdisMIndicateStatus message */
+struct rndis_indicate_status {
+	u32 status;
+	u32 status_buflen;
+	u32 status_buf_offset;
+};
+
+/* Diagnostic information passed as the status buffer in */
+/* struct rndis_indicate_status messages signifying error conditions. */
+struct rndis_diagnostic_info {
+	u32 diag_status;
+	u32 error_offset;
+};
+
+/* NdisKeepAlive message */
+struct rndis_keepalive_request {
+	u32 req_id;
+};
+
+/* Response to NdisKeepAlive */
+struct rndis_keepalive_complete {
+	u32 req_id;
+	u32 status;
+};
+
+/*
+ * Data message. All Offset fields contain byte offsets from the beginning of
+ * struct rndis_packet. All Length fields are in bytes.  VcHandle is set
+ * to 0 for connectionless data, otherwise it contains the VC handle.
+ */
+struct rndis_packet {
+	u32 data_offset;
+	u32 data_len;
+	u32 oob_data_offset;
+	u32 oob_data_len;
+	u32 num_oob_data_elements;
+	u32 per_pkt_info_offset;
+	u32 per_pkt_info_len;
+	u32 vc_handle;
+	u32 reserved;
+};
+
+/* Optional Out of Band data associated with a Data message. */
+struct rndis_oobd {
+	u32 size;
+	u32 type;
+	u32 class_info_offset;
+};
+
+/* Packet extension field contents associated with a Data message. */
+struct rndis_per_packet_info {
+	u32 size;
+	u32 type;
+	u32 ppi_offset;
+};
+
+enum ndis_per_pkt_info_type {
+	TCPIP_CHKSUM_PKTINFO,
+	IPSEC_PKTINFO,
+	TCP_LARGESEND_PKTINFO,
+	CLASSIFICATION_HANDLE_PKTINFO,
+	NDIS_RESERVED,
+	SG_LIST_PKTINFO,
+	IEEE_8021Q_INFO,
+	ORIGINAL_PKTINFO,
+	PACKET_CANCEL_ID,
+	NBL_HASH_VALUE = PACKET_CANCEL_ID,
+	ORIGINAL_NET_BUFLIST,
+	CACHED_NET_BUFLIST,
+	SHORT_PKT_PADINFO,
+	MAX_PER_PKT_INFO
+};
+
+struct ndis_pkt_8021q_info {
+	union {
+		struct {
+			u32 pri:3; /* User Priority */
+			u32 cfi:1; /* Canonical Format ID */
+			u32 vlanid:12; /* VLAN ID */
+			u32 reserved:16;
+		};
+		u32 value;
+	};
+};
+
+struct ndis_oject_header {
+	u8 type;
+	u8 revision;
+	u16 size;
+};
+
+#define NDIS_OBJECT_TYPE_DEFAULT	0x80
+#define NDIS_OFFLOAD_PARAMETERS_REVISION_3 3
+#define NDIS_OFFLOAD_PARAMETERS_NO_CHANGE 0
+#define NDIS_OFFLOAD_PARAMETERS_LSOV2_DISABLED 1
+#define NDIS_OFFLOAD_PARAMETERS_LSOV2_ENABLED  2
+#define NDIS_OFFLOAD_PARAMETERS_LSOV1_ENABLED  2
+#define NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED 1
+#define NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED 2
+#define NDIS_OFFLOAD_PARAMETERS_TX_RX_DISABLED 1
+#define NDIS_OFFLOAD_PARAMETERS_TX_ENABLED_RX_DISABLED 2
+#define NDIS_OFFLOAD_PARAMETERS_RX_ENABLED_TX_DISABLED 3
+#define NDIS_OFFLOAD_PARAMETERS_TX_RX_ENABLED 4
+
+#define NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE	1
+#define NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4	0
+#define NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6	1
+
+#define VERSION_4_OFFLOAD_SIZE			22
+/*
+ * New offload OIDs for NDIS 6
+ */
+#define OID_TCP_OFFLOAD_CURRENT_CONFIG 0xFC01020B /* query only */
+#define OID_TCP_OFFLOAD_PARAMETERS 0xFC01020C		/* set only */
+#define OID_TCP_OFFLOAD_HARDWARE_CAPABILITIES 0xFC01020D/* query only */
+#define OID_TCP_CONNECTION_OFFLOAD_CURRENT_CONFIG 0xFC01020E /* query only */
+#define OID_TCP_CONNECTION_OFFLOAD_HARDWARE_CAPABILITIES 0xFC01020F /* query */
+#define OID_OFFLOAD_ENCAPSULATION 0x0101010A /* set/query */
+
+struct ndis_offload_params {
+	struct ndis_oject_header header;
+	u8 ip_v4_csum;
+	u8 tcp_ip_v4_csum;
+	u8 udp_ip_v4_csum;
+	u8 tcp_ip_v6_csum;
+	u8 udp_ip_v6_csum;
+	u8 lso_v1;
+	u8 ip_sec_v1;
+	u8 lso_v2_ipv4;
+	u8 lso_v2_ipv6;
+	u8 tcp_connection_ip_v4;
+	u8 tcp_connection_ip_v6;
+	u32 flags;
+	u8 ip_sec_v2;
+	u8 ip_sec_v2_ip_v4;
+	struct {
+		u8 rsc_ip_v4;
+		u8 rsc_ip_v6;
+	};
+	struct {
+		u8 encapsulated_packet_task_offload;
+		u8 encapsulation_types;
+	};
+};
+
+struct ndis_tcp_ip_checksum_info {
+	union {
+		struct {
+			u32 is_ipv4:1;
+			u32 is_ipv6:1;
+			u32 tcp_checksum:1;
+			u32 udp_checksum:1;
+			u32 ip_header_checksum:1;
+			u32 reserved:11;
+			u32 tcp_header_offset:10;
+		} transmit;
+		struct {
+			u32 tcp_checksum_failed:1;
+			u32 udp_checksum_failed:1;
+			u32 ip_checksum_failed:1;
+			u32 tcp_checksum_succeeded:1;
+			u32 udp_checksum_succeeded:1;
+			u32 ip_checksum_succeeded:1;
+			u32 loopback:1;
+			u32 tcp_checksum_value_invalid:1;
+			u32 ip_checksum_value_invalid:1;
+		} receive;
+		u32  value;
+	};
+};
+
+struct ndis_tcp_lso_info {
+	union {
+		struct {
+			u32 unused:30;
+			u32 type:1;
+			u32 reserved2:1;
+		} transmit;
+		struct {
+			u32 mss:20;
+			u32 tcp_header_offset:10;
+			u32 type:1;
+			u32 reserved2:1;
+		} lso_v1_transmit;
+		struct {
+			u32 tcp_payload:30;
+			u32 type:1;
+			u32 reserved2:1;
+		} lso_v1_transmit_complete;
+		struct {
+			u32 mss:20;
+			u32 tcp_header_offset:10;
+			u32 type:1;
+			u32 ip_version:1;
+		} lso_v2_transmit;
+		struct {
+			u32 reserved:30;
+			u32 type:1;
+			u32 reserved2:1;
+		} lso_v2_transmit_complete;
+		u32  value;
+	};
+};
+
+#define NDIS_VLAN_PPI_SIZE (sizeof(struct rndis_per_packet_info) + \
+		sizeof(struct ndis_pkt_8021q_info))
+
+#define NDIS_CSUM_PPI_SIZE (sizeof(struct rndis_per_packet_info) + \
+		sizeof(struct ndis_tcp_ip_checksum_info))
+
+#define NDIS_LSO_PPI_SIZE (sizeof(struct rndis_per_packet_info) + \
+		sizeof(struct ndis_tcp_lso_info))
+
+#define NDIS_HASH_PPI_SIZE (sizeof(struct rndis_per_packet_info) + \
+		sizeof(u32))
+
+/* Total size of all PPI data */
+#define NDIS_ALL_PPI_SIZE (NDIS_VLAN_PPI_SIZE + NDIS_CSUM_PPI_SIZE + \
+			   NDIS_LSO_PPI_SIZE + NDIS_HASH_PPI_SIZE)
+
+/* Format of Information buffer passed in a SetRequest for the OID */
+/* OID_GEN_RNDIS_CONFIG_PARAMETER. */
+struct rndis_config_parameter_info {
+	u32 parameter_name_offset;
+	u32 parameter_name_length;
+	u32 parameter_type;
+	u32 parameter_value_offset;
+	u32 parameter_value_length;
+};
+
+/* Values for ParameterType in struct rndis_config_parameter_info */
+#define RNDIS_CONFIG_PARAM_TYPE_INTEGER     0
+#define RNDIS_CONFIG_PARAM_TYPE_STRING      2
+
+/* CONDIS Miniport messages for connection oriented devices */
+/* that do not implement a call manager. */
+
+/* CoNdisMiniportCreateVc message */
+struct rcondis_mp_create_vc {
+	u32 req_id;
+	u32 ndis_vc_handle;
+};
+
+/* Response to CoNdisMiniportCreateVc */
+struct rcondis_mp_create_vc_complete {
+	u32 req_id;
+	u32 dev_vc_handle;
+	u32 status;
+};
+
+/* CoNdisMiniportDeleteVc message */
+struct rcondis_mp_delete_vc {
+	u32 req_id;
+	u32 dev_vc_handle;
+};
+
+/* Response to CoNdisMiniportDeleteVc */
+struct rcondis_mp_delete_vc_complete {
+	u32 req_id;
+	u32 status;
+};
+
+/* CoNdisMiniportQueryRequest message */
+struct rcondis_mp_query_request {
+	u32 req_id;
+	u32 request_type;
+	u32 oid;
+	u32 dev_vc_handle;
+	u32 info_buflen;
+	u32 info_buf_offset;
+};
+
+/* CoNdisMiniportSetRequest message */
+struct rcondis_mp_set_request {
+	u32 req_id;
+	u32 request_type;
+	u32 oid;
+	u32 dev_vc_handle;
+	u32 info_buflen;
+	u32 info_buf_offset;
+};
+
+/* CoNdisIndicateStatus message */
+struct rcondis_indicate_status {
+	u32 ndis_vc_handle;
+	u32 status;
+	u32 status_buflen;
+	u32 status_buf_offset;
+};
+
+/* CONDIS Call/VC parameters */
+struct rcondis_specific_parameters {
+	u32 parameter_type;
+	u32 parameter_length;
+	u32 parameter_lffset;
+};
+
+struct rcondis_media_parameters {
+	u32 flags;
+	u32 reserved1;
+	u32 reserved2;
+	struct rcondis_specific_parameters media_specific;
+};
+
+struct rndis_flowspec {
+	u32 token_rate;
+	u32 token_bucket_size;
+	u32 peak_bandwidth;
+	u32 latency;
+	u32 delay_variation;
+	u32 service_type;
+	u32 max_sdu_size;
+	u32 minimum_policed_size;
+};
+
+struct rcondis_call_manager_parameters {
+	struct rndis_flowspec transmit;
+	struct rndis_flowspec receive;
+	struct rcondis_specific_parameters call_mgr_specific;
+};
+
+/* CoNdisMiniportActivateVc message */
+struct rcondis_mp_activate_vc_request {
+	u32 req_id;
+	u32 flags;
+	u32 dev_vc_handle;
+	u32 media_params_offset;
+	u32 media_params_length;
+	u32 call_mgr_params_offset;
+	u32 call_mgr_params_length;
+};
+
+/* Response to CoNdisMiniportActivateVc */
+struct rcondis_mp_activate_vc_complete {
+	u32 req_id;
+	u32 status;
+};
+
+/* CoNdisMiniportDeactivateVc message */
+struct rcondis_mp_deactivate_vc_request {
+	u32 req_id;
+	u32 flags;
+	u32 dev_vc_handle;
+};
+
+/* Response to CoNdisMiniportDeactivateVc */
+struct rcondis_mp_deactivate_vc_complete {
+	u32 req_id;
+	u32 status;
+};
+
+
+/* union with all of the RNDIS messages */
+union rndis_message_container {
+	struct rndis_packet pkt;
+	struct rndis_initialize_request init_req;
+	struct rndis_halt_request halt_req;
+	struct rndis_query_request query_req;
+	struct rndis_set_request set_req;
+	struct rndis_reset_request reset_req;
+	struct rndis_keepalive_request keep_alive_req;
+	struct rndis_indicate_status indicate_status;
+	struct rndis_initialize_complete init_complete;
+	struct rndis_query_complete query_complete;
+	struct rndis_set_complete set_complete;
+	struct rndis_reset_complete reset_complete;
+	struct rndis_keepalive_complete keep_alive_complete;
+	struct rcondis_mp_create_vc co_miniport_create_vc;
+	struct rcondis_mp_delete_vc co_miniport_delete_vc;
+	struct rcondis_indicate_status co_indicate_status;
+	struct rcondis_mp_activate_vc_request co_miniport_activate_vc;
+	struct rcondis_mp_deactivate_vc_request co_miniport_deactivate_vc;
+	struct rcondis_mp_create_vc_complete co_miniport_create_vc_complete;
+	struct rcondis_mp_delete_vc_complete co_miniport_delete_vc_complete;
+	struct rcondis_mp_activate_vc_complete co_miniport_activate_vc_complete;
+	struct rcondis_mp_deactivate_vc_complete
+		co_miniport_deactivate_vc_complete;
+};
+
+/* Remote NDIS message format */
+struct rndis_message {
+	u32 ndis_msg_type;
+
+	/* Total length of this message, from the beginning */
+	/* of the sruct rndis_message, in bytes. */
+	u32 msg_len;
+
+	/* Actual message */
+	union rndis_message_container msg;
+};
+
+
+/* Handy macros */
+
+/* get the size of an RNDIS message. Pass in the message type, */
+/* struct rndis_set_request, struct rndis_packet for example */
+#define RNDIS_MESSAGE_SIZE(msg)				\
+	(sizeof(msg) + (sizeof(struct rndis_message) -	\
+	 sizeof(union rndis_message_container)))
+
+/* get pointer to info buffer with message pointer */
+#define MESSAGE_TO_INFO_BUFFER(msg)				\
+	(((unsigned char *)(msg)) + msg->info_buf_offset)
+
+/* get pointer to status buffer with message pointer */
+#define MESSAGE_TO_STATUS_BUFFER(msg)			\
+	(((unsigned char *)(msg)) + msg->status_buf_offset)
+
+/* get pointer to OOBD buffer with message pointer */
+#define MESSAGE_TO_OOBD_BUFFER(msg)				\
+	(((unsigned char *)(msg)) + msg->oob_data_offset)
+
+/* get pointer to data buffer with message pointer */
+#define MESSAGE_TO_DATA_BUFFER(msg)				\
+	(((unsigned char *)(msg)) + msg->per_pkt_info_offset)
+
+/* get pointer to contained message from NDIS_MESSAGE pointer */
+#define RNDIS_MESSAGE_PTR_TO_MESSAGE_PTR(rndis_msg)		\
+	((void *) &rndis_msg->msg)
+
+/* get pointer to contained message from NDIS_MESSAGE pointer */
+#define RNDIS_MESSAGE_RAW_PTR_TO_MESSAGE_PTR(rndis_msg)	\
+	((void *) rndis_msg)
+
+
+#define __struct_bcount(x)
+
+
+
+#define RNDIS_HEADER_SIZE	(sizeof(struct rndis_message) - \
+				 sizeof(union rndis_message_container))
+
+#define RNDIS_AND_PPI_SIZE (sizeof(struct rndis_message) + NDIS_ALL_PPI_SIZE)
+
+#define NDIS_PACKET_TYPE_DIRECTED	0x00000001
+#define NDIS_PACKET_TYPE_MULTICAST	0x00000002
+#define NDIS_PACKET_TYPE_ALL_MULTICAST	0x00000004
+#define NDIS_PACKET_TYPE_BROADCAST	0x00000008
+#define NDIS_PACKET_TYPE_SOURCE_ROUTING	0x00000010
+#define NDIS_PACKET_TYPE_PROMISCUOUS	0x00000020
+#define NDIS_PACKET_TYPE_SMT		0x00000040
+#define NDIS_PACKET_TYPE_ALL_LOCAL	0x00000080
+#define NDIS_PACKET_TYPE_GROUP		0x00000100
+#define NDIS_PACKET_TYPE_ALL_FUNCTIONAL	0x00000200
+#define NDIS_PACKET_TYPE_FUNCTIONAL	0x00000400
+#define NDIS_PACKET_TYPE_MAC_FRAME	0x00000800
+
+#define INFO_IPV4       2
+#define INFO_IPV6       4
+#define INFO_TCP        2
+#define INFO_UDP        4
+
+#define TRANSPORT_INFO_NOT_IP   0
+#define TRANSPORT_INFO_IPV4_TCP ((INFO_IPV4 << 16) | INFO_TCP)
+#define TRANSPORT_INFO_IPV4_UDP ((INFO_IPV4 << 16) | INFO_UDP)
+#define TRANSPORT_INFO_IPV6_TCP ((INFO_IPV6 << 16) | INFO_TCP)
+#define TRANSPORT_INFO_IPV6_UDP ((INFO_IPV6 << 16) | INFO_UDP)
+
+
+#endif /* _HYPERV_NET_H */
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
new file mode 100644
index 000000000..ea091bc5f
--- /dev/null
+++ b/drivers/net/hyperv/netvsc.c
@@ -0,0 +1,1231 @@
+/*
+ * Copyright (c) 2009, 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, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/if_ether.h>
+#include <asm/sync_bitops.h>
+
+#include "hyperv_net.h"
+
+
+static struct netvsc_device *alloc_net_device(struct hv_device *device)
+{
+	struct netvsc_device *net_device;
+	struct net_device *ndev = hv_get_drvdata(device);
+	int i;
+
+	net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
+	if (!net_device)
+		return NULL;
+
+	net_device->cb_buffer = kzalloc(NETVSC_PACKET_SIZE, GFP_KERNEL);
+	if (!net_device->cb_buffer) {
+		kfree(net_device);
+		return NULL;
+	}
+
+	init_waitqueue_head(&net_device->wait_drain);
+	net_device->start_remove = false;
+	net_device->destroy = false;
+	net_device->dev = device;
+	net_device->ndev = ndev;
+	net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
+	net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
+
+	for (i = 0; i < num_online_cpus(); i++)
+		spin_lock_init(&net_device->msd[i].lock);
+
+	hv_set_drvdata(device, net_device);
+	return net_device;
+}
+
+static void free_netvsc_device(struct netvsc_device *nvdev)
+{
+	kfree(nvdev->cb_buffer);
+	kfree(nvdev);
+}
+
+static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
+{
+	struct netvsc_device *net_device;
+
+	net_device = hv_get_drvdata(device);
+	if (net_device && net_device->destroy)
+		net_device = NULL;
+
+	return net_device;
+}
+
+static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
+{
+	struct netvsc_device *net_device;
+
+	net_device = hv_get_drvdata(device);
+
+	if (!net_device)
+		goto get_in_err;
+
+	if (net_device->destroy &&
+		atomic_read(&net_device->num_outstanding_sends) == 0)
+		net_device = NULL;
+
+get_in_err:
+	return net_device;
+}
+
+
+static int netvsc_destroy_buf(struct netvsc_device *net_device)
+{
+	struct nvsp_message *revoke_packet;
+	int ret = 0;
+	struct net_device *ndev = net_device->ndev;
+
+	/*
+	 * If we got a section count, it means we received a
+	 * SendReceiveBufferComplete msg (ie sent
+	 * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
+	 * to send a revoke msg here
+	 */
+	if (net_device->recv_section_cnt) {
+		/* Send the revoke receive buffer */
+		revoke_packet = &net_device->revoke_packet;
+		memset(revoke_packet, 0, sizeof(struct nvsp_message));
+
+		revoke_packet->hdr.msg_type =
+			NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
+		revoke_packet->msg.v1_msg.
+		revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
+
+		ret = vmbus_sendpacket(net_device->dev->channel,
+				       revoke_packet,
+				       sizeof(struct nvsp_message),
+				       (unsigned long)revoke_packet,
+				       VM_PKT_DATA_INBAND, 0);
+		/*
+		 * If we failed here, we might as well return and
+		 * have a leak rather than continue and a bugchk
+		 */
+		if (ret != 0) {
+			netdev_err(ndev, "unable to send "
+				"revoke receive buffer to netvsp\n");
+			return ret;
+		}
+	}
+
+	/* Teardown the gpadl on the vsp end */
+	if (net_device->recv_buf_gpadl_handle) {
+		ret = vmbus_teardown_gpadl(net_device->dev->channel,
+			   net_device->recv_buf_gpadl_handle);
+
+		/* If we failed here, we might as well return and have a leak
+		 * rather than continue and a bugchk
+		 */
+		if (ret != 0) {
+			netdev_err(ndev,
+				   "unable to teardown receive buffer's gpadl\n");
+			return ret;
+		}
+		net_device->recv_buf_gpadl_handle = 0;
+	}
+
+	if (net_device->recv_buf) {
+		/* Free up the receive buffer */
+		vfree(net_device->recv_buf);
+		net_device->recv_buf = NULL;
+	}
+
+	if (net_device->recv_section) {
+		net_device->recv_section_cnt = 0;
+		kfree(net_device->recv_section);
+		net_device->recv_section = NULL;
+	}
+
+	/* Deal with the send buffer we may have setup.
+	 * If we got a  send section size, it means we received a
+	 * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
+	 * NVSP_MSG1_TYPE_SEND_SEND_BUF msg) therefore, we need
+	 * to send a revoke msg here
+	 */
+	if (net_device->send_section_size) {
+		/* Send the revoke receive buffer */
+		revoke_packet = &net_device->revoke_packet;
+		memset(revoke_packet, 0, sizeof(struct nvsp_message));
+
+		revoke_packet->hdr.msg_type =
+			NVSP_MSG1_TYPE_REVOKE_SEND_BUF;
+		revoke_packet->msg.v1_msg.revoke_send_buf.id =
+			NETVSC_SEND_BUFFER_ID;
+
+		ret = vmbus_sendpacket(net_device->dev->channel,
+				       revoke_packet,
+				       sizeof(struct nvsp_message),
+				       (unsigned long)revoke_packet,
+				       VM_PKT_DATA_INBAND, 0);
+		/* If we failed here, we might as well return and
+		 * have a leak rather than continue and a bugchk
+		 */
+		if (ret != 0) {
+			netdev_err(ndev, "unable to send "
+				   "revoke send buffer to netvsp\n");
+			return ret;
+		}
+	}
+	/* Teardown the gpadl on the vsp end */
+	if (net_device->send_buf_gpadl_handle) {
+		ret = vmbus_teardown_gpadl(net_device->dev->channel,
+					   net_device->send_buf_gpadl_handle);
+
+		/* If we failed here, we might as well return and have a leak
+		 * rather than continue and a bugchk
+		 */
+		if (ret != 0) {
+			netdev_err(ndev,
+				   "unable to teardown send buffer's gpadl\n");
+			return ret;
+		}
+		net_device->send_buf_gpadl_handle = 0;
+	}
+	if (net_device->send_buf) {
+		/* Free up the send buffer */
+		vfree(net_device->send_buf);
+		net_device->send_buf = NULL;
+	}
+	kfree(net_device->send_section_map);
+
+	return ret;
+}
+
+static int netvsc_init_buf(struct hv_device *device)
+{
+	int ret = 0;
+	unsigned long t;
+	struct netvsc_device *net_device;
+	struct nvsp_message *init_packet;
+	struct net_device *ndev;
+
+	net_device = get_outbound_net_device(device);
+	if (!net_device)
+		return -ENODEV;
+	ndev = net_device->ndev;
+
+	net_device->recv_buf = vzalloc(net_device->recv_buf_size);
+	if (!net_device->recv_buf) {
+		netdev_err(ndev, "unable to allocate receive "
+			"buffer of size %d\n", net_device->recv_buf_size);
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	/*
+	 * Establish the gpadl handle for this buffer on this
+	 * channel.  Note: This call uses the vmbus connection rather
+	 * than the channel to establish the gpadl handle.
+	 */
+	ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
+				    net_device->recv_buf_size,
+				    &net_device->recv_buf_gpadl_handle);
+	if (ret != 0) {
+		netdev_err(ndev,
+			"unable to establish receive buffer's gpadl\n");
+		goto cleanup;
+	}
+
+
+	/* Notify the NetVsp of the gpadl handle */
+	init_packet = &net_device->channel_init_pkt;
+
+	memset(init_packet, 0, sizeof(struct nvsp_message));
+
+	init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
+	init_packet->msg.v1_msg.send_recv_buf.
+		gpadl_handle = net_device->recv_buf_gpadl_handle;
+	init_packet->msg.v1_msg.
+		send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
+
+	/* Send the gpadl notification request */
+	ret = vmbus_sendpacket(device->channel, init_packet,
+			       sizeof(struct nvsp_message),
+			       (unsigned long)init_packet,
+			       VM_PKT_DATA_INBAND,
+			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+	if (ret != 0) {
+		netdev_err(ndev,
+			"unable to send receive buffer's gpadl to netvsp\n");
+		goto cleanup;
+	}
+
+	t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
+	BUG_ON(t == 0);
+
+
+	/* Check the response */
+	if (init_packet->msg.v1_msg.
+	    send_recv_buf_complete.status != NVSP_STAT_SUCCESS) {
+		netdev_err(ndev, "Unable to complete receive buffer "
+			   "initialization with NetVsp - status %d\n",
+			   init_packet->msg.v1_msg.
+			   send_recv_buf_complete.status);
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	/* Parse the response */
+
+	net_device->recv_section_cnt = init_packet->msg.
+		v1_msg.send_recv_buf_complete.num_sections;
+
+	net_device->recv_section = kmemdup(
+		init_packet->msg.v1_msg.send_recv_buf_complete.sections,
+		net_device->recv_section_cnt *
+		sizeof(struct nvsp_1_receive_buffer_section),
+		GFP_KERNEL);
+	if (net_device->recv_section == NULL) {
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	/*
+	 * For 1st release, there should only be 1 section that represents the
+	 * entire receive buffer
+	 */
+	if (net_device->recv_section_cnt != 1 ||
+	    net_device->recv_section->offset != 0) {
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	/* Now setup the send buffer.
+	 */
+	net_device->send_buf = vzalloc(net_device->send_buf_size);
+	if (!net_device->send_buf) {
+		netdev_err(ndev, "unable to allocate send "
+			   "buffer of size %d\n", net_device->send_buf_size);
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	/* Establish the gpadl handle for this buffer on this
+	 * channel.  Note: This call uses the vmbus connection rather
+	 * than the channel to establish the gpadl handle.
+	 */
+	ret = vmbus_establish_gpadl(device->channel, net_device->send_buf,
+				    net_device->send_buf_size,
+				    &net_device->send_buf_gpadl_handle);
+	if (ret != 0) {
+		netdev_err(ndev,
+			   "unable to establish send buffer's gpadl\n");
+		goto cleanup;
+	}
+
+	/* Notify the NetVsp of the gpadl handle */
+	init_packet = &net_device->channel_init_pkt;
+	memset(init_packet, 0, sizeof(struct nvsp_message));
+	init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
+	init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
+		net_device->send_buf_gpadl_handle;
+	init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;
+
+	/* Send the gpadl notification request */
+	ret = vmbus_sendpacket(device->channel, init_packet,
+			       sizeof(struct nvsp_message),
+			       (unsigned long)init_packet,
+			       VM_PKT_DATA_INBAND,
+			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+	if (ret != 0) {
+		netdev_err(ndev,
+			   "unable to send send buffer's gpadl to netvsp\n");
+		goto cleanup;
+	}
+
+	t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
+	BUG_ON(t == 0);
+
+	/* Check the response */
+	if (init_packet->msg.v1_msg.
+	    send_send_buf_complete.status != NVSP_STAT_SUCCESS) {
+		netdev_err(ndev, "Unable to complete send buffer "
+			   "initialization with NetVsp - status %d\n",
+			   init_packet->msg.v1_msg.
+			   send_send_buf_complete.status);
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	/* Parse the response */
+	net_device->send_section_size = init_packet->msg.
+				v1_msg.send_send_buf_complete.section_size;
+
+	/* Section count is simply the size divided by the section size.
+	 */
+	net_device->send_section_cnt =
+		net_device->send_buf_size/net_device->send_section_size;
+
+	dev_info(&device->device, "Send section size: %d, Section count:%d\n",
+		 net_device->send_section_size, net_device->send_section_cnt);
+
+	/* Setup state for managing the send buffer. */
+	net_device->map_words = DIV_ROUND_UP(net_device->send_section_cnt,
+					     BITS_PER_LONG);
+
+	net_device->send_section_map =
+		kzalloc(net_device->map_words * sizeof(ulong), GFP_KERNEL);
+	if (net_device->send_section_map == NULL) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	goto exit;
+
+cleanup:
+	netvsc_destroy_buf(net_device);
+
+exit:
+	return ret;
+}
+
+
+/* Negotiate NVSP protocol version */
+static int negotiate_nvsp_ver(struct hv_device *device,
+			      struct netvsc_device *net_device,
+			      struct nvsp_message *init_packet,
+			      u32 nvsp_ver)
+{
+	int ret;
+	unsigned long t;
+
+	memset(init_packet, 0, sizeof(struct nvsp_message));
+	init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
+	init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
+	init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
+
+	/* Send the init request */
+	ret = vmbus_sendpacket(device->channel, init_packet,
+			       sizeof(struct nvsp_message),
+			       (unsigned long)init_packet,
+			       VM_PKT_DATA_INBAND,
+			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+	if (ret != 0)
+		return ret;
+
+	t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
+
+	if (t == 0)
+		return -ETIMEDOUT;
+
+	if (init_packet->msg.init_msg.init_complete.status !=
+	    NVSP_STAT_SUCCESS)
+		return -EINVAL;
+
+	if (nvsp_ver == NVSP_PROTOCOL_VERSION_1)
+		return 0;
+
+	/* NVSPv2 only: Send NDIS config */
+	memset(init_packet, 0, sizeof(struct nvsp_message));
+	init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
+	init_packet->msg.v2_msg.send_ndis_config.mtu = net_device->ndev->mtu +
+						       ETH_HLEN;
+	init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
+
+	ret = vmbus_sendpacket(device->channel, init_packet,
+				sizeof(struct nvsp_message),
+				(unsigned long)init_packet,
+				VM_PKT_DATA_INBAND, 0);
+
+	return ret;
+}
+
+static int netvsc_connect_vsp(struct hv_device *device)
+{
+	int ret;
+	struct netvsc_device *net_device;
+	struct nvsp_message *init_packet;
+	int ndis_version;
+	struct net_device *ndev;
+	u32 ver_list[] = { NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
+		NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5 };
+	int i, num_ver = 4; /* number of different NVSP versions */
+
+	net_device = get_outbound_net_device(device);
+	if (!net_device)
+		return -ENODEV;
+	ndev = net_device->ndev;
+
+	init_packet = &net_device->channel_init_pkt;
+
+	/* Negotiate the latest NVSP protocol supported */
+	for (i = num_ver - 1; i >= 0; i--)
+		if (negotiate_nvsp_ver(device, net_device, init_packet,
+				       ver_list[i])  == 0) {
+			net_device->nvsp_version = ver_list[i];
+			break;
+		}
+
+	if (i < 0) {
+		ret = -EPROTO;
+		goto cleanup;
+	}
+
+	pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
+
+	/* Send the ndis version */
+	memset(init_packet, 0, sizeof(struct nvsp_message));
+
+	if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_4)
+		ndis_version = 0x00060001;
+	else
+		ndis_version = 0x0006001e;
+
+	init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
+	init_packet->msg.v1_msg.
+		send_ndis_ver.ndis_major_ver =
+				(ndis_version & 0xFFFF0000) >> 16;
+	init_packet->msg.v1_msg.
+		send_ndis_ver.ndis_minor_ver =
+				ndis_version & 0xFFFF;
+
+	/* Send the init request */
+	ret = vmbus_sendpacket(device->channel, init_packet,
+				sizeof(struct nvsp_message),
+				(unsigned long)init_packet,
+				VM_PKT_DATA_INBAND, 0);
+	if (ret != 0)
+		goto cleanup;
+
+	/* Post the big receive buffer to NetVSP */
+	if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
+		net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
+	else
+		net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
+	net_device->send_buf_size = NETVSC_SEND_BUFFER_SIZE;
+
+	ret = netvsc_init_buf(device);
+
+cleanup:
+	return ret;
+}
+
+static void netvsc_disconnect_vsp(struct netvsc_device *net_device)
+{
+	netvsc_destroy_buf(net_device);
+}
+
+/*
+ * netvsc_device_remove - Callback when the root bus device is removed
+ */
+int netvsc_device_remove(struct hv_device *device)
+{
+	struct netvsc_device *net_device;
+	unsigned long flags;
+
+	net_device = hv_get_drvdata(device);
+
+	netvsc_disconnect_vsp(net_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.
+	 */
+
+	spin_lock_irqsave(&device->channel->inbound_lock, flags);
+	hv_set_drvdata(device, NULL);
+	spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+	/*
+	 * At this point, no one should be accessing net_device
+	 * except in here
+	 */
+	dev_notice(&device->device, "net device safe to remove\n");
+
+	/* Now, we can close the channel safely */
+	vmbus_close(device->channel);
+
+	/* Release all resources */
+	vfree(net_device->sub_cb_buf);
+	free_netvsc_device(net_device);
+	return 0;
+}
+
+
+#define RING_AVAIL_PERCENT_HIWATER 20
+#define RING_AVAIL_PERCENT_LOWATER 10
+
+/*
+ * Get the percentage of available bytes to write in the ring.
+ * The return value is in range from 0 to 100.
+ */
+static inline u32 hv_ringbuf_avail_percent(
+		struct hv_ring_buffer_info *ring_info)
+{
+	u32 avail_read, avail_write;
+
+	hv_get_ringbuffer_availbytes(ring_info, &avail_read, &avail_write);
+
+	return avail_write * 100 / ring_info->ring_datasize;
+}
+
+static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
+					 u32 index)
+{
+	sync_change_bit(index, net_device->send_section_map);
+}
+
+static void netvsc_send_completion(struct netvsc_device *net_device,
+				   struct hv_device *device,
+				   struct vmpacket_descriptor *packet)
+{
+	struct nvsp_message *nvsp_packet;
+	struct hv_netvsc_packet *nvsc_packet;
+	struct net_device *ndev;
+	u32 send_index;
+
+	ndev = net_device->ndev;
+
+	nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
+			(packet->offset8 << 3));
+
+	if ((nvsp_packet->hdr.msg_type == NVSP_MSG_TYPE_INIT_COMPLETE) ||
+	    (nvsp_packet->hdr.msg_type ==
+	     NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE) ||
+	    (nvsp_packet->hdr.msg_type ==
+	     NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE) ||
+	    (nvsp_packet->hdr.msg_type ==
+	     NVSP_MSG5_TYPE_SUBCHANNEL)) {
+		/* Copy the response back */
+		memcpy(&net_device->channel_init_pkt, nvsp_packet,
+		       sizeof(struct nvsp_message));
+		complete(&net_device->channel_init_wait);
+	} else if (nvsp_packet->hdr.msg_type ==
+		   NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE) {
+		int num_outstanding_sends;
+		u16 q_idx = 0;
+		struct vmbus_channel *channel = device->channel;
+		int queue_sends;
+
+		/* Get the send context */
+		nvsc_packet = (struct hv_netvsc_packet *)(unsigned long)
+			packet->trans_id;
+
+		/* Notify the layer above us */
+		if (nvsc_packet) {
+			send_index = nvsc_packet->send_buf_index;
+			if (send_index != NETVSC_INVALID_INDEX)
+				netvsc_free_send_slot(net_device, send_index);
+			q_idx = nvsc_packet->q_idx;
+			channel = nvsc_packet->channel;
+			nvsc_packet->send_completion(nvsc_packet->
+						     send_completion_ctx);
+		}
+
+		num_outstanding_sends =
+			atomic_dec_return(&net_device->num_outstanding_sends);
+		queue_sends = atomic_dec_return(&net_device->
+						queue_sends[q_idx]);
+
+		if (net_device->destroy && num_outstanding_sends == 0)
+			wake_up(&net_device->wait_drain);
+
+		if (netif_tx_queue_stopped(netdev_get_tx_queue(ndev, q_idx)) &&
+		    !net_device->start_remove &&
+		    (hv_ringbuf_avail_percent(&channel->outbound) >
+		     RING_AVAIL_PERCENT_HIWATER || queue_sends < 1))
+				netif_tx_wake_queue(netdev_get_tx_queue(
+						    ndev, q_idx));
+	} else {
+		netdev_err(ndev, "Unknown send completion packet type- "
+			   "%d received!!\n", nvsp_packet->hdr.msg_type);
+	}
+
+}
+
+static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
+{
+	unsigned long index;
+	u32 max_words = net_device->map_words;
+	unsigned long *map_addr = (unsigned long *)net_device->send_section_map;
+	u32 section_cnt = net_device->send_section_cnt;
+	int ret_val = NETVSC_INVALID_INDEX;
+	int i;
+	int prev_val;
+
+	for (i = 0; i < max_words; i++) {
+		if (!~(map_addr[i]))
+			continue;
+		index = ffz(map_addr[i]);
+		prev_val = sync_test_and_set_bit(index, &map_addr[i]);
+		if (prev_val)
+			continue;
+		if ((index + (i * BITS_PER_LONG)) >= section_cnt)
+			break;
+		ret_val = (index + (i * BITS_PER_LONG));
+		break;
+	}
+	return ret_val;
+}
+
+static u32 netvsc_copy_to_send_buf(struct netvsc_device *net_device,
+				   unsigned int section_index,
+				   u32 pend_size,
+				   struct hv_netvsc_packet *packet)
+{
+	char *start = net_device->send_buf;
+	char *dest = start + (section_index * net_device->send_section_size)
+		     + pend_size;
+	int i;
+	u32 msg_size = 0;
+	u32 padding = 0;
+	u32 remain = packet->total_data_buflen % net_device->pkt_align;
+	u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
+		packet->page_buf_cnt;
+
+	/* Add padding */
+	if (packet->is_data_pkt && packet->xmit_more && remain &&
+	    !packet->cp_partial) {
+		padding = net_device->pkt_align - remain;
+		packet->rndis_msg->msg_len += padding;
+		packet->total_data_buflen += padding;
+	}
+
+	for (i = 0; i < page_count; i++) {
+		char *src = phys_to_virt(packet->page_buf[i].pfn << PAGE_SHIFT);
+		u32 offset = packet->page_buf[i].offset;
+		u32 len = packet->page_buf[i].len;
+
+		memcpy(dest, (src + offset), len);
+		msg_size += len;
+		dest += len;
+	}
+
+	if (padding) {
+		memset(dest, 0, padding);
+		msg_size += padding;
+	}
+
+	return msg_size;
+}
+
+static inline int netvsc_send_pkt(
+	struct hv_netvsc_packet *packet,
+	struct netvsc_device *net_device)
+{
+	struct nvsp_message nvmsg;
+	struct vmbus_channel *out_channel = packet->channel;
+	u16 q_idx = packet->q_idx;
+	struct net_device *ndev = net_device->ndev;
+	u64 req_id;
+	int ret;
+	struct hv_page_buffer *pgbuf;
+
+	nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
+	if (packet->is_data_pkt) {
+		/* 0 is RMC_DATA; */
+		nvmsg.msg.v1_msg.send_rndis_pkt.channel_type = 0;
+	} else {
+		/* 1 is RMC_CONTROL; */
+		nvmsg.msg.v1_msg.send_rndis_pkt.channel_type = 1;
+	}
+
+	nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_index =
+		packet->send_buf_index;
+	if (packet->send_buf_index == NETVSC_INVALID_INDEX)
+		nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_size = 0;
+	else
+		nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_size =
+			packet->total_data_buflen;
+
+	if (packet->send_completion)
+		req_id = (ulong)packet;
+	else
+		req_id = 0;
+
+	if (out_channel->rescind)
+		return -ENODEV;
+
+	if (packet->page_buf_cnt) {
+		pgbuf = packet->cp_partial ? packet->page_buf +
+			packet->rmsg_pgcnt : packet->page_buf;
+		ret = vmbus_sendpacket_pagebuffer(out_channel,
+						  pgbuf,
+						  packet->page_buf_cnt,
+						  &nvmsg,
+						  sizeof(struct nvsp_message),
+						  req_id);
+	} else {
+		ret = vmbus_sendpacket(
+				out_channel, &nvmsg,
+				sizeof(struct nvsp_message),
+				req_id,
+				VM_PKT_DATA_INBAND,
+				VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+	}
+
+	if (ret == 0) {
+		atomic_inc(&net_device->num_outstanding_sends);
+		atomic_inc(&net_device->queue_sends[q_idx]);
+
+		if (hv_ringbuf_avail_percent(&out_channel->outbound) <
+			RING_AVAIL_PERCENT_LOWATER) {
+			netif_tx_stop_queue(netdev_get_tx_queue(
+					    ndev, q_idx));
+
+			if (atomic_read(&net_device->
+				queue_sends[q_idx]) < 1)
+				netif_tx_wake_queue(netdev_get_tx_queue(
+						    ndev, q_idx));
+		}
+	} else if (ret == -EAGAIN) {
+		netif_tx_stop_queue(netdev_get_tx_queue(
+				    ndev, q_idx));
+		if (atomic_read(&net_device->queue_sends[q_idx]) < 1) {
+			netif_tx_wake_queue(netdev_get_tx_queue(
+					    ndev, q_idx));
+			ret = -ENOSPC;
+		}
+	} else {
+		netdev_err(ndev, "Unable to send packet %p ret %d\n",
+			   packet, ret);
+	}
+
+	return ret;
+}
+
+int netvsc_send(struct hv_device *device,
+		struct hv_netvsc_packet *packet)
+{
+	struct netvsc_device *net_device;
+	int ret = 0, m_ret = 0;
+	struct vmbus_channel *out_channel;
+	u16 q_idx = packet->q_idx;
+	u32 pktlen = packet->total_data_buflen, msd_len = 0;
+	unsigned int section_index = NETVSC_INVALID_INDEX;
+	unsigned long flag;
+	struct multi_send_data *msdp;
+	struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
+	bool try_batch;
+
+	net_device = get_outbound_net_device(device);
+	if (!net_device)
+		return -ENODEV;
+
+	out_channel = net_device->chn_table[q_idx];
+	if (!out_channel) {
+		out_channel = device->channel;
+		q_idx = 0;
+		packet->q_idx = 0;
+	}
+	packet->channel = out_channel;
+	packet->send_buf_index = NETVSC_INVALID_INDEX;
+	packet->cp_partial = false;
+
+	msdp = &net_device->msd[q_idx];
+
+	/* batch packets in send buffer if possible */
+	spin_lock_irqsave(&msdp->lock, flag);
+	if (msdp->pkt)
+		msd_len = msdp->pkt->total_data_buflen;
+
+	try_batch = packet->is_data_pkt && msd_len > 0 && msdp->count <
+		    net_device->max_pkt;
+
+	if (try_batch && msd_len + pktlen + net_device->pkt_align <
+	    net_device->send_section_size) {
+		section_index = msdp->pkt->send_buf_index;
+
+	} else if (try_batch && msd_len + packet->rmsg_size <
+		   net_device->send_section_size) {
+		section_index = msdp->pkt->send_buf_index;
+		packet->cp_partial = true;
+
+	} else if (packet->is_data_pkt && pktlen + net_device->pkt_align <
+		   net_device->send_section_size) {
+		section_index = netvsc_get_next_send_section(net_device);
+		if (section_index != NETVSC_INVALID_INDEX) {
+				msd_send = msdp->pkt;
+				msdp->pkt = NULL;
+				msdp->count = 0;
+				msd_len = 0;
+		}
+	}
+
+	if (section_index != NETVSC_INVALID_INDEX) {
+		netvsc_copy_to_send_buf(net_device,
+					section_index, msd_len,
+					packet);
+
+		packet->send_buf_index = section_index;
+
+		if (packet->cp_partial) {
+			packet->page_buf_cnt -= packet->rmsg_pgcnt;
+			packet->total_data_buflen = msd_len + packet->rmsg_size;
+		} else {
+			packet->page_buf_cnt = 0;
+			packet->total_data_buflen += msd_len;
+		}
+
+		if (msdp->pkt)
+			netvsc_xmit_completion(msdp->pkt);
+
+		if (packet->xmit_more && !packet->cp_partial) {
+			msdp->pkt = packet;
+			msdp->count++;
+		} else {
+			cur_send = packet;
+			msdp->pkt = NULL;
+			msdp->count = 0;
+		}
+	} else {
+		msd_send = msdp->pkt;
+		msdp->pkt = NULL;
+		msdp->count = 0;
+		cur_send = packet;
+	}
+
+	spin_unlock_irqrestore(&msdp->lock, flag);
+
+	if (msd_send) {
+		m_ret = netvsc_send_pkt(msd_send, net_device);
+
+		if (m_ret != 0) {
+			netvsc_free_send_slot(net_device,
+					      msd_send->send_buf_index);
+			netvsc_xmit_completion(msd_send);
+		}
+	}
+
+	if (cur_send)
+		ret = netvsc_send_pkt(cur_send, net_device);
+
+	if (ret != 0 && section_index != NETVSC_INVALID_INDEX)
+		netvsc_free_send_slot(net_device, section_index);
+
+	return ret;
+}
+
+static void netvsc_send_recv_completion(struct hv_device *device,
+					struct vmbus_channel *channel,
+					struct netvsc_device *net_device,
+					u64 transaction_id, u32 status)
+{
+	struct nvsp_message recvcompMessage;
+	int retries = 0;
+	int ret;
+	struct net_device *ndev;
+
+	ndev = net_device->ndev;
+
+	recvcompMessage.hdr.msg_type =
+				NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE;
+
+	recvcompMessage.msg.v1_msg.send_rndis_pkt_complete.status = status;
+
+retry_send_cmplt:
+	/* Send the completion */
+	ret = vmbus_sendpacket(channel, &recvcompMessage,
+			       sizeof(struct nvsp_message), transaction_id,
+			       VM_PKT_COMP, 0);
+	if (ret == 0) {
+		/* success */
+		/* no-op */
+	} else if (ret == -EAGAIN) {
+		/* no more room...wait a bit and attempt to retry 3 times */
+		retries++;
+		netdev_err(ndev, "unable to send receive completion pkt"
+			" (tid %llx)...retrying %d\n", transaction_id, retries);
+
+		if (retries < 4) {
+			udelay(100);
+			goto retry_send_cmplt;
+		} else {
+			netdev_err(ndev, "unable to send receive "
+				"completion pkt (tid %llx)...give up retrying\n",
+				transaction_id);
+		}
+	} else {
+		netdev_err(ndev, "unable to send receive "
+			"completion pkt - %llx\n", transaction_id);
+	}
+}
+
+static void netvsc_receive(struct netvsc_device *net_device,
+			struct vmbus_channel *channel,
+			struct hv_device *device,
+			struct vmpacket_descriptor *packet)
+{
+	struct vmtransfer_page_packet_header *vmxferpage_packet;
+	struct nvsp_message *nvsp_packet;
+	struct hv_netvsc_packet nv_pkt;
+	struct hv_netvsc_packet *netvsc_packet = &nv_pkt;
+	u32 status = NVSP_STAT_SUCCESS;
+	int i;
+	int count = 0;
+	struct net_device *ndev;
+
+	ndev = net_device->ndev;
+
+	/*
+	 * All inbound packets other than send completion should be xfer page
+	 * packet
+	 */
+	if (packet->type != VM_PKT_DATA_USING_XFER_PAGES) {
+		netdev_err(ndev, "Unknown packet type received - %d\n",
+			   packet->type);
+		return;
+	}
+
+	nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
+			(packet->offset8 << 3));
+
+	/* Make sure this is a valid nvsp packet */
+	if (nvsp_packet->hdr.msg_type !=
+	    NVSP_MSG1_TYPE_SEND_RNDIS_PKT) {
+		netdev_err(ndev, "Unknown nvsp packet type received-"
+			" %d\n", nvsp_packet->hdr.msg_type);
+		return;
+	}
+
+	vmxferpage_packet = (struct vmtransfer_page_packet_header *)packet;
+
+	if (vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID) {
+		netdev_err(ndev, "Invalid xfer page set id - "
+			   "expecting %x got %x\n", NETVSC_RECEIVE_BUFFER_ID,
+			   vmxferpage_packet->xfer_pageset_id);
+		return;
+	}
+
+	count = vmxferpage_packet->range_cnt;
+	netvsc_packet->channel = channel;
+
+	/* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
+	for (i = 0; i < count; i++) {
+		/* Initialize the netvsc packet */
+		netvsc_packet->status = NVSP_STAT_SUCCESS;
+		netvsc_packet->data = (void *)((unsigned long)net_device->
+			recv_buf + vmxferpage_packet->ranges[i].byte_offset);
+		netvsc_packet->total_data_buflen =
+					vmxferpage_packet->ranges[i].byte_count;
+
+		/* Pass it to the upper layer */
+		rndis_filter_receive(device, netvsc_packet);
+
+		if (netvsc_packet->status != NVSP_STAT_SUCCESS)
+			status = NVSP_STAT_FAIL;
+	}
+
+	netvsc_send_recv_completion(device, channel, net_device,
+				    vmxferpage_packet->d.trans_id, status);
+}
+
+
+static void netvsc_send_table(struct hv_device *hdev,
+			      struct vmpacket_descriptor *vmpkt)
+{
+	struct netvsc_device *nvscdev;
+	struct net_device *ndev;
+	struct nvsp_message *nvmsg;
+	int i;
+	u32 count, *tab;
+
+	nvscdev = get_outbound_net_device(hdev);
+	if (!nvscdev)
+		return;
+	ndev = nvscdev->ndev;
+
+	nvmsg = (struct nvsp_message *)((unsigned long)vmpkt +
+					(vmpkt->offset8 << 3));
+
+	if (nvmsg->hdr.msg_type != NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE)
+		return;
+
+	count = nvmsg->msg.v5_msg.send_table.count;
+	if (count != VRSS_SEND_TAB_SIZE) {
+		netdev_err(ndev, "Received wrong send-table size:%u\n", count);
+		return;
+	}
+
+	tab = (u32 *)((unsigned long)&nvmsg->msg.v5_msg.send_table +
+		      nvmsg->msg.v5_msg.send_table.offset);
+
+	for (i = 0; i < count; i++)
+		nvscdev->send_table[i] = tab[i];
+}
+
+void netvsc_channel_cb(void *context)
+{
+	int ret;
+	struct vmbus_channel *channel = (struct vmbus_channel *)context;
+	struct hv_device *device;
+	struct netvsc_device *net_device;
+	u32 bytes_recvd;
+	u64 request_id;
+	struct vmpacket_descriptor *desc;
+	unsigned char *buffer;
+	int bufferlen = NETVSC_PACKET_SIZE;
+	struct net_device *ndev;
+
+	if (channel->primary_channel != NULL)
+		device = channel->primary_channel->device_obj;
+	else
+		device = channel->device_obj;
+
+	net_device = get_inbound_net_device(device);
+	if (!net_device)
+		return;
+	ndev = net_device->ndev;
+	buffer = get_per_channel_state(channel);
+
+	do {
+		ret = vmbus_recvpacket_raw(channel, buffer, bufferlen,
+					   &bytes_recvd, &request_id);
+		if (ret == 0) {
+			if (bytes_recvd > 0) {
+				desc = (struct vmpacket_descriptor *)buffer;
+				switch (desc->type) {
+				case VM_PKT_COMP:
+					netvsc_send_completion(net_device,
+								device, desc);
+					break;
+
+				case VM_PKT_DATA_USING_XFER_PAGES:
+					netvsc_receive(net_device, channel,
+						       device, desc);
+					break;
+
+				case VM_PKT_DATA_INBAND:
+					netvsc_send_table(device, desc);
+					break;
+
+				default:
+					netdev_err(ndev,
+						   "unhandled packet type %d, "
+						   "tid %llx len %d\n",
+						   desc->type, request_id,
+						   bytes_recvd);
+					break;
+				}
+
+			} else {
+				/*
+				 * We are done for this pass.
+				 */
+				break;
+			}
+
+		} else if (ret == -ENOBUFS) {
+			if (bufferlen > NETVSC_PACKET_SIZE)
+				kfree(buffer);
+			/* Handle large packet */
+			buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
+			if (buffer == NULL) {
+				/* Try again next time around */
+				netdev_err(ndev,
+					   "unable to allocate buffer of size "
+					   "(%d)!!\n", bytes_recvd);
+				break;
+			}
+
+			bufferlen = bytes_recvd;
+		}
+	} while (1);
+
+	if (bufferlen > NETVSC_PACKET_SIZE)
+		kfree(buffer);
+	return;
+}
+
+/*
+ * netvsc_device_add - Callback when the device belonging to this
+ * driver is added
+ */
+int netvsc_device_add(struct hv_device *device, void *additional_info)
+{
+	int ret = 0;
+	int ring_size =
+	((struct netvsc_device_info *)additional_info)->ring_size;
+	struct netvsc_device *net_device;
+	struct net_device *ndev;
+
+	net_device = alloc_net_device(device);
+	if (!net_device)
+		return -ENOMEM;
+
+	net_device->ring_size = ring_size;
+
+	/*
+	 * Coming into this function, struct net_device * is
+	 * registered as the driver private data.
+	 * In alloc_net_device(), we register struct netvsc_device *
+	 * as the driver private data and stash away struct net_device *
+	 * in struct netvsc_device *.
+	 */
+	ndev = net_device->ndev;
+
+	/* Add netvsc_device context to netvsc_device */
+	net_device->nd_ctx = netdev_priv(ndev);
+
+	/* Initialize the NetVSC channel extension */
+	init_completion(&net_device->channel_init_wait);
+
+	set_per_channel_state(device->channel, net_device->cb_buffer);
+
+	/* Open the channel */
+	ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
+			 ring_size * PAGE_SIZE, NULL, 0,
+			 netvsc_channel_cb, device->channel);
+
+	if (ret != 0) {
+		netdev_err(ndev, "unable to open channel: %d\n", ret);
+		goto cleanup;
+	}
+
+	/* Channel is opened */
+	pr_info("hv_netvsc channel opened successfully\n");
+
+	net_device->chn_table[0] = device->channel;
+
+	/* Connect with the NetVsp */
+	ret = netvsc_connect_vsp(device);
+	if (ret != 0) {
+		netdev_err(ndev,
+			"unable to connect to NetVSP - %d\n", ret);
+		goto close;
+	}
+
+	return ret;
+
+close:
+	/* Now, we can close the channel safely */
+	vmbus_close(device->channel);
+
+cleanup:
+	free_netvsc_device(net_device);
+
+	return ret;
+}
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
new file mode 100644
index 000000000..5993c7e2d
--- /dev/null
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -0,0 +1,1004 @@
+/*
+ * Copyright (c) 2009, 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, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/atomic.h>
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/if_vlan.h>
+#include <linux/in.h>
+#include <linux/slab.h>
+#include <net/arp.h>
+#include <net/route.h>
+#include <net/sock.h>
+#include <net/pkt_sched.h>
+
+#include "hyperv_net.h"
+
+
+#define RING_SIZE_MIN 64
+static int ring_size = 128;
+module_param(ring_size, int, S_IRUGO);
+MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
+
+static const u32 default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
+				NETIF_MSG_LINK | NETIF_MSG_IFUP |
+				NETIF_MSG_IFDOWN | NETIF_MSG_RX_ERR |
+				NETIF_MSG_TX_ERR;
+
+static int debug = -1;
+module_param(debug, int, S_IRUGO);
+MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
+
+static void do_set_multicast(struct work_struct *w)
+{
+	struct net_device_context *ndevctx =
+		container_of(w, struct net_device_context, work);
+	struct netvsc_device *nvdev;
+	struct rndis_device *rdev;
+
+	nvdev = hv_get_drvdata(ndevctx->device_ctx);
+	if (nvdev == NULL || nvdev->ndev == NULL)
+		return;
+
+	rdev = nvdev->extension;
+	if (rdev == NULL)
+		return;
+
+	if (nvdev->ndev->flags & IFF_PROMISC)
+		rndis_filter_set_packet_filter(rdev,
+			NDIS_PACKET_TYPE_PROMISCUOUS);
+	else
+		rndis_filter_set_packet_filter(rdev,
+			NDIS_PACKET_TYPE_BROADCAST |
+			NDIS_PACKET_TYPE_ALL_MULTICAST |
+			NDIS_PACKET_TYPE_DIRECTED);
+}
+
+static void netvsc_set_multicast_list(struct net_device *net)
+{
+	struct net_device_context *net_device_ctx = netdev_priv(net);
+
+	schedule_work(&net_device_ctx->work);
+}
+
+static int netvsc_open(struct net_device *net)
+{
+	struct net_device_context *net_device_ctx = netdev_priv(net);
+	struct hv_device *device_obj = net_device_ctx->device_ctx;
+	struct netvsc_device *nvdev;
+	struct rndis_device *rdev;
+	int ret = 0;
+
+	netif_carrier_off(net);
+
+	/* Open up the device */
+	ret = rndis_filter_open(device_obj);
+	if (ret != 0) {
+		netdev_err(net, "unable to open device (ret %d).\n", ret);
+		return ret;
+	}
+
+	netif_tx_start_all_queues(net);
+
+	nvdev = hv_get_drvdata(device_obj);
+	rdev = nvdev->extension;
+	if (!rdev->link_state)
+		netif_carrier_on(net);
+
+	return ret;
+}
+
+static int netvsc_close(struct net_device *net)
+{
+	struct net_device_context *net_device_ctx = netdev_priv(net);
+	struct hv_device *device_obj = net_device_ctx->device_ctx;
+	int ret;
+
+	netif_tx_disable(net);
+
+	/* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
+	cancel_work_sync(&net_device_ctx->work);
+	ret = rndis_filter_close(device_obj);
+	if (ret != 0)
+		netdev_err(net, "unable to close device (ret %d).\n", ret);
+
+	return ret;
+}
+
+static void *init_ppi_data(struct rndis_message *msg, u32 ppi_size,
+				int pkt_type)
+{
+	struct rndis_packet *rndis_pkt;
+	struct rndis_per_packet_info *ppi;
+
+	rndis_pkt = &msg->msg.pkt;
+	rndis_pkt->data_offset += ppi_size;
+
+	ppi = (struct rndis_per_packet_info *)((void *)rndis_pkt +
+		rndis_pkt->per_pkt_info_offset + rndis_pkt->per_pkt_info_len);
+
+	ppi->size = ppi_size;
+	ppi->type = pkt_type;
+	ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
+
+	rndis_pkt->per_pkt_info_len += ppi_size;
+
+	return ppi;
+}
+
+union sub_key {
+	u64 k;
+	struct {
+		u8 pad[3];
+		u8 kb;
+		u32 ka;
+	};
+};
+
+/* Toeplitz hash function
+ * data: network byte order
+ * return: host byte order
+ */
+static u32 comp_hash(u8 *key, int klen, void *data, int dlen)
+{
+	union sub_key subk;
+	int k_next = 4;
+	u8 dt;
+	int i, j;
+	u32 ret = 0;
+
+	subk.k = 0;
+	subk.ka = ntohl(*(u32 *)key);
+
+	for (i = 0; i < dlen; i++) {
+		subk.kb = key[k_next];
+		k_next = (k_next + 1) % klen;
+		dt = ((u8 *)data)[i];
+		for (j = 0; j < 8; j++) {
+			if (dt & 0x80)
+				ret ^= subk.ka;
+			dt <<= 1;
+			subk.k <<= 1;
+		}
+	}
+
+	return ret;
+}
+
+static bool netvsc_set_hash(u32 *hash, struct sk_buff *skb)
+{
+	struct flow_keys flow;
+	int data_len;
+
+	if (!skb_flow_dissect(skb, &flow) ||
+	    !(flow.n_proto == htons(ETH_P_IP) ||
+	      flow.n_proto == htons(ETH_P_IPV6)))
+		return false;
+
+	if (flow.ip_proto == IPPROTO_TCP)
+		data_len = 12;
+	else
+		data_len = 8;
+
+	*hash = comp_hash(netvsc_hash_key, HASH_KEYLEN, &flow, data_len);
+
+	return true;
+}
+
+static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
+			void *accel_priv, select_queue_fallback_t fallback)
+{
+	struct net_device_context *net_device_ctx = netdev_priv(ndev);
+	struct hv_device *hdev =  net_device_ctx->device_ctx;
+	struct netvsc_device *nvsc_dev = hv_get_drvdata(hdev);
+	u32 hash;
+	u16 q_idx = 0;
+
+	if (nvsc_dev == NULL || ndev->real_num_tx_queues <= 1)
+		return 0;
+
+	if (netvsc_set_hash(&hash, skb)) {
+		q_idx = nvsc_dev->send_table[hash % VRSS_SEND_TAB_SIZE] %
+			ndev->real_num_tx_queues;
+		skb_set_hash(skb, hash, PKT_HASH_TYPE_L3);
+	}
+
+	return q_idx;
+}
+
+void netvsc_xmit_completion(void *context)
+{
+	struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
+	struct sk_buff *skb = (struct sk_buff *)
+		(unsigned long)packet->send_completion_tid;
+
+	if (skb)
+		dev_kfree_skb_any(skb);
+}
+
+static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
+			struct hv_page_buffer *pb)
+{
+	int j = 0;
+
+	/* Deal with compund pages by ignoring unused part
+	 * of the page.
+	 */
+	page += (offset >> PAGE_SHIFT);
+	offset &= ~PAGE_MASK;
+
+	while (len > 0) {
+		unsigned long bytes;
+
+		bytes = PAGE_SIZE - offset;
+		if (bytes > len)
+			bytes = len;
+		pb[j].pfn = page_to_pfn(page);
+		pb[j].offset = offset;
+		pb[j].len = bytes;
+
+		offset += bytes;
+		len -= bytes;
+
+		if (offset == PAGE_SIZE && len) {
+			page++;
+			offset = 0;
+			j++;
+		}
+	}
+
+	return j + 1;
+}
+
+static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
+			   struct hv_netvsc_packet *packet)
+{
+	struct hv_page_buffer *pb = packet->page_buf;
+	u32 slots_used = 0;
+	char *data = skb->data;
+	int frags = skb_shinfo(skb)->nr_frags;
+	int i;
+
+	/* The packet is laid out thus:
+	 * 1. hdr: RNDIS header and PPI
+	 * 2. skb linear data
+	 * 3. skb fragment data
+	 */
+	if (hdr != NULL)
+		slots_used += fill_pg_buf(virt_to_page(hdr),
+					offset_in_page(hdr),
+					len, &pb[slots_used]);
+
+	packet->rmsg_size = len;
+	packet->rmsg_pgcnt = slots_used;
+
+	slots_used += fill_pg_buf(virt_to_page(data),
+				offset_in_page(data),
+				skb_headlen(skb), &pb[slots_used]);
+
+	for (i = 0; i < frags; i++) {
+		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
+
+		slots_used += fill_pg_buf(skb_frag_page(frag),
+					frag->page_offset,
+					skb_frag_size(frag), &pb[slots_used]);
+	}
+	return slots_used;
+}
+
+static int count_skb_frag_slots(struct sk_buff *skb)
+{
+	int i, frags = skb_shinfo(skb)->nr_frags;
+	int pages = 0;
+
+	for (i = 0; i < frags; i++) {
+		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
+		unsigned long size = skb_frag_size(frag);
+		unsigned long offset = frag->page_offset;
+
+		/* Skip unused frames from start of page */
+		offset &= ~PAGE_MASK;
+		pages += PFN_UP(offset + size);
+	}
+	return pages;
+}
+
+static int netvsc_get_slots(struct sk_buff *skb)
+{
+	char *data = skb->data;
+	unsigned int offset = offset_in_page(data);
+	unsigned int len = skb_headlen(skb);
+	int slots;
+	int frag_slots;
+
+	slots = DIV_ROUND_UP(offset + len, PAGE_SIZE);
+	frag_slots = count_skb_frag_slots(skb);
+	return slots + frag_slots;
+}
+
+static u32 get_net_transport_info(struct sk_buff *skb, u32 *trans_off)
+{
+	u32 ret_val = TRANSPORT_INFO_NOT_IP;
+
+	if ((eth_hdr(skb)->h_proto != htons(ETH_P_IP)) &&
+		(eth_hdr(skb)->h_proto != htons(ETH_P_IPV6))) {
+		goto not_ip;
+	}
+
+	*trans_off = skb_transport_offset(skb);
+
+	if ((eth_hdr(skb)->h_proto == htons(ETH_P_IP))) {
+		struct iphdr *iphdr = ip_hdr(skb);
+
+		if (iphdr->protocol == IPPROTO_TCP)
+			ret_val = TRANSPORT_INFO_IPV4_TCP;
+		else if (iphdr->protocol == IPPROTO_UDP)
+			ret_val = TRANSPORT_INFO_IPV4_UDP;
+	} else {
+		if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
+			ret_val = TRANSPORT_INFO_IPV6_TCP;
+		else if (ipv6_hdr(skb)->nexthdr == IPPROTO_UDP)
+			ret_val = TRANSPORT_INFO_IPV6_UDP;
+	}
+
+not_ip:
+	return ret_val;
+}
+
+static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
+{
+	struct net_device_context *net_device_ctx = netdev_priv(net);
+	struct hv_netvsc_packet *packet = NULL;
+	int ret;
+	unsigned int num_data_pgs;
+	struct rndis_message *rndis_msg;
+	struct rndis_packet *rndis_pkt;
+	u32 rndis_msg_size;
+	bool isvlan;
+	bool linear = false;
+	struct rndis_per_packet_info *ppi;
+	struct ndis_tcp_ip_checksum_info *csum_info;
+	struct ndis_tcp_lso_info *lso_info;
+	int  hdr_offset;
+	u32 net_trans_info;
+	u32 hash;
+	u32 skb_length;
+	u32 pkt_sz;
+	struct hv_page_buffer page_buf[MAX_PAGE_BUFFER_COUNT];
+
+
+	/* We will atmost need two pages to describe the rndis
+	 * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
+	 * of pages in a single packet. If skb is scattered around
+	 * more pages we try linearizing it.
+	 */
+
+check_size:
+	skb_length = skb->len;
+	num_data_pgs = netvsc_get_slots(skb) + 2;
+	if (num_data_pgs > MAX_PAGE_BUFFER_COUNT && linear) {
+		net_alert_ratelimited("packet too big: %u pages (%u bytes)\n",
+				      num_data_pgs, skb->len);
+		ret = -EFAULT;
+		goto drop;
+	} else if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
+		if (skb_linearize(skb)) {
+			net_alert_ratelimited("failed to linearize skb\n");
+			ret = -ENOMEM;
+			goto drop;
+		}
+		linear = true;
+		goto check_size;
+	}
+
+	pkt_sz = sizeof(struct hv_netvsc_packet) + RNDIS_AND_PPI_SIZE;
+
+	ret = skb_cow_head(skb, pkt_sz);
+	if (ret) {
+		netdev_err(net, "unable to alloc hv_netvsc_packet\n");
+		ret = -ENOMEM;
+		goto drop;
+	}
+	/* Use the headroom for building up the packet */
+	packet = (struct hv_netvsc_packet *)skb->head;
+
+	packet->status = 0;
+	packet->xmit_more = skb->xmit_more;
+
+	packet->vlan_tci = skb->vlan_tci;
+	packet->page_buf = page_buf;
+
+	packet->q_idx = skb_get_queue_mapping(skb);
+
+	packet->is_data_pkt = true;
+	packet->total_data_buflen = skb->len;
+
+	packet->rndis_msg = (struct rndis_message *)((unsigned long)packet +
+				sizeof(struct hv_netvsc_packet));
+
+	memset(packet->rndis_msg, 0, RNDIS_AND_PPI_SIZE);
+
+	/* Set the completion routine */
+	packet->send_completion = netvsc_xmit_completion;
+	packet->send_completion_ctx = packet;
+	packet->send_completion_tid = (unsigned long)skb;
+
+	isvlan = packet->vlan_tci & VLAN_TAG_PRESENT;
+
+	/* Add the rndis header */
+	rndis_msg = packet->rndis_msg;
+	rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
+	rndis_msg->msg_len = packet->total_data_buflen;
+	rndis_pkt = &rndis_msg->msg.pkt;
+	rndis_pkt->data_offset = sizeof(struct rndis_packet);
+	rndis_pkt->data_len = packet->total_data_buflen;
+	rndis_pkt->per_pkt_info_offset = sizeof(struct rndis_packet);
+
+	rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
+
+	hash = skb_get_hash_raw(skb);
+	if (hash != 0 && net->real_num_tx_queues > 1) {
+		rndis_msg_size += NDIS_HASH_PPI_SIZE;
+		ppi = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
+				    NBL_HASH_VALUE);
+		*(u32 *)((void *)ppi + ppi->ppi_offset) = hash;
+	}
+
+	if (isvlan) {
+		struct ndis_pkt_8021q_info *vlan;
+
+		rndis_msg_size += NDIS_VLAN_PPI_SIZE;
+		ppi = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
+					IEEE_8021Q_INFO);
+		vlan = (struct ndis_pkt_8021q_info *)((void *)ppi +
+						ppi->ppi_offset);
+		vlan->vlanid = packet->vlan_tci & VLAN_VID_MASK;
+		vlan->pri = (packet->vlan_tci & VLAN_PRIO_MASK) >>
+				VLAN_PRIO_SHIFT;
+	}
+
+	net_trans_info = get_net_transport_info(skb, &hdr_offset);
+	if (net_trans_info == TRANSPORT_INFO_NOT_IP)
+		goto do_send;
+
+	/*
+	 * Setup the sendside checksum offload only if this is not a
+	 * GSO packet.
+	 */
+	if (skb_is_gso(skb))
+		goto do_lso;
+
+	if ((skb->ip_summed == CHECKSUM_NONE) ||
+	    (skb->ip_summed == CHECKSUM_UNNECESSARY))
+		goto do_send;
+
+	rndis_msg_size += NDIS_CSUM_PPI_SIZE;
+	ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
+			    TCPIP_CHKSUM_PKTINFO);
+
+	csum_info = (struct ndis_tcp_ip_checksum_info *)((void *)ppi +
+			ppi->ppi_offset);
+
+	if (net_trans_info & (INFO_IPV4 << 16))
+		csum_info->transmit.is_ipv4 = 1;
+	else
+		csum_info->transmit.is_ipv6 = 1;
+
+	if (net_trans_info & INFO_TCP) {
+		csum_info->transmit.tcp_checksum = 1;
+		csum_info->transmit.tcp_header_offset = hdr_offset;
+	} else if (net_trans_info & INFO_UDP) {
+		/* UDP checksum offload is not supported on ws2008r2.
+		 * Furthermore, on ws2012 and ws2012r2, there are some
+		 * issues with udp checksum offload from Linux guests.
+		 * (these are host issues).
+		 * For now compute the checksum here.
+		 */
+		struct udphdr *uh;
+		u16 udp_len;
+
+		ret = skb_cow_head(skb, 0);
+		if (ret)
+			goto drop;
+
+		uh = udp_hdr(skb);
+		udp_len = ntohs(uh->len);
+		uh->check = 0;
+		uh->check = csum_tcpudp_magic(ip_hdr(skb)->saddr,
+					      ip_hdr(skb)->daddr,
+					      udp_len, IPPROTO_UDP,
+					      csum_partial(uh, udp_len, 0));
+		if (uh->check == 0)
+			uh->check = CSUM_MANGLED_0;
+
+		csum_info->transmit.udp_checksum = 0;
+	}
+	goto do_send;
+
+do_lso:
+	rndis_msg_size += NDIS_LSO_PPI_SIZE;
+	ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
+			    TCP_LARGESEND_PKTINFO);
+
+	lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
+			ppi->ppi_offset);
+
+	lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
+	if (net_trans_info & (INFO_IPV4 << 16)) {
+		lso_info->lso_v2_transmit.ip_version =
+			NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
+		ip_hdr(skb)->tot_len = 0;
+		ip_hdr(skb)->check = 0;
+		tcp_hdr(skb)->check =
+		~csum_tcpudp_magic(ip_hdr(skb)->saddr,
+				   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
+	} else {
+		lso_info->lso_v2_transmit.ip_version =
+			NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
+		ipv6_hdr(skb)->payload_len = 0;
+		tcp_hdr(skb)->check =
+		~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
+				&ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
+	}
+	lso_info->lso_v2_transmit.tcp_header_offset = hdr_offset;
+	lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
+
+do_send:
+	/* Start filling in the page buffers with the rndis hdr */
+	rndis_msg->msg_len += rndis_msg_size;
+	packet->total_data_buflen = rndis_msg->msg_len;
+	packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
+					       skb, packet);
+
+	ret = netvsc_send(net_device_ctx->device_ctx, packet);
+
+drop:
+	if (ret == 0) {
+		net->stats.tx_bytes += skb_length;
+		net->stats.tx_packets++;
+	} else {
+		if (ret != -EAGAIN) {
+			dev_kfree_skb_any(skb);
+			net->stats.tx_dropped++;
+		}
+	}
+
+	return (ret == -EAGAIN) ? NETDEV_TX_BUSY : NETDEV_TX_OK;
+}
+
+/*
+ * netvsc_linkstatus_callback - Link up/down notification
+ */
+void netvsc_linkstatus_callback(struct hv_device *device_obj,
+				struct rndis_message *resp)
+{
+	struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
+	struct net_device *net;
+	struct net_device_context *ndev_ctx;
+	struct netvsc_device *net_device;
+	struct rndis_device *rdev;
+
+	net_device = hv_get_drvdata(device_obj);
+	rdev = net_device->extension;
+
+	switch (indicate->status) {
+	case RNDIS_STATUS_MEDIA_CONNECT:
+		rdev->link_state = false;
+		break;
+	case RNDIS_STATUS_MEDIA_DISCONNECT:
+		rdev->link_state = true;
+		break;
+	case RNDIS_STATUS_NETWORK_CHANGE:
+		rdev->link_change = true;
+		break;
+	default:
+		return;
+	}
+
+	net = net_device->ndev;
+
+	if (!net || net->reg_state != NETREG_REGISTERED)
+		return;
+
+	ndev_ctx = netdev_priv(net);
+	if (!rdev->link_state) {
+		schedule_delayed_work(&ndev_ctx->dwork, 0);
+		schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
+	} else {
+		schedule_delayed_work(&ndev_ctx->dwork, 0);
+	}
+}
+
+/*
+ * netvsc_recv_callback -  Callback when we receive a packet from the
+ * "wire" on the specified device.
+ */
+int netvsc_recv_callback(struct hv_device *device_obj,
+				struct hv_netvsc_packet *packet,
+				struct ndis_tcp_ip_checksum_info *csum_info)
+{
+	struct net_device *net;
+	struct sk_buff *skb;
+
+	net = ((struct netvsc_device *)hv_get_drvdata(device_obj))->ndev;
+	if (!net || net->reg_state != NETREG_REGISTERED) {
+		packet->status = NVSP_STAT_FAIL;
+		return 0;
+	}
+
+	/* Allocate a skb - TODO direct I/O to pages? */
+	skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
+	if (unlikely(!skb)) {
+		++net->stats.rx_dropped;
+		packet->status = NVSP_STAT_FAIL;
+		return 0;
+	}
+
+	/*
+	 * Copy to skb. This copy is needed here since the memory pointed by
+	 * hv_netvsc_packet cannot be deallocated
+	 */
+	memcpy(skb_put(skb, packet->total_data_buflen), packet->data,
+		packet->total_data_buflen);
+
+	skb->protocol = eth_type_trans(skb, net);
+	if (csum_info) {
+		/* We only look at the IP checksum here.
+		 * Should we be dropping the packet if checksum
+		 * failed? How do we deal with other checksums - TCP/UDP?
+		 */
+		if (csum_info->receive.ip_checksum_succeeded)
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+		else
+			skb->ip_summed = CHECKSUM_NONE;
+	}
+
+	if (packet->vlan_tci & VLAN_TAG_PRESENT)
+		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
+				       packet->vlan_tci);
+
+	skb_record_rx_queue(skb, packet->channel->
+			    offermsg.offer.sub_channel_index);
+
+	net->stats.rx_packets++;
+	net->stats.rx_bytes += packet->total_data_buflen;
+
+	/*
+	 * Pass the skb back up. Network stack will deallocate the skb when it
+	 * is done.
+	 * TODO - use NAPI?
+	 */
+	netif_rx(skb);
+
+	return 0;
+}
+
+static void netvsc_get_drvinfo(struct net_device *net,
+			       struct ethtool_drvinfo *info)
+{
+	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
+	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
+}
+
+static void netvsc_get_channels(struct net_device *net,
+				struct ethtool_channels *channel)
+{
+	struct net_device_context *net_device_ctx = netdev_priv(net);
+	struct hv_device *dev = net_device_ctx->device_ctx;
+	struct netvsc_device *nvdev = hv_get_drvdata(dev);
+
+	if (nvdev) {
+		channel->max_combined	= nvdev->max_chn;
+		channel->combined_count = nvdev->num_chn;
+	}
+}
+
+static int netvsc_change_mtu(struct net_device *ndev, int mtu)
+{
+	struct net_device_context *ndevctx = netdev_priv(ndev);
+	struct hv_device *hdev =  ndevctx->device_ctx;
+	struct netvsc_device *nvdev = hv_get_drvdata(hdev);
+	struct netvsc_device_info device_info;
+	int limit = ETH_DATA_LEN;
+
+	if (nvdev == NULL || nvdev->destroy)
+		return -ENODEV;
+
+	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
+		limit = NETVSC_MTU - ETH_HLEN;
+
+	/* Hyper-V hosts don't support MTU < ETH_DATA_LEN (1500) */
+	if (mtu < ETH_DATA_LEN || mtu > limit)
+		return -EINVAL;
+
+	nvdev->start_remove = true;
+	cancel_work_sync(&ndevctx->work);
+	netif_tx_disable(ndev);
+	rndis_filter_device_remove(hdev);
+
+	ndev->mtu = mtu;
+
+	ndevctx->device_ctx = hdev;
+	hv_set_drvdata(hdev, ndev);
+	device_info.ring_size = ring_size;
+	rndis_filter_device_add(hdev, &device_info);
+	netif_tx_wake_all_queues(ndev);
+
+	return 0;
+}
+
+
+static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
+{
+	struct net_device_context *ndevctx = netdev_priv(ndev);
+	struct hv_device *hdev =  ndevctx->device_ctx;
+	struct sockaddr *addr = p;
+	char save_adr[ETH_ALEN];
+	unsigned char save_aatype;
+	int err;
+
+	memcpy(save_adr, ndev->dev_addr, ETH_ALEN);
+	save_aatype = ndev->addr_assign_type;
+
+	err = eth_mac_addr(ndev, p);
+	if (err != 0)
+		return err;
+
+	err = rndis_filter_set_device_mac(hdev, addr->sa_data);
+	if (err != 0) {
+		/* roll back to saved MAC */
+		memcpy(ndev->dev_addr, save_adr, ETH_ALEN);
+		ndev->addr_assign_type = save_aatype;
+	}
+
+	return err;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void netvsc_poll_controller(struct net_device *net)
+{
+	/* As netvsc_start_xmit() works synchronous we don't have to
+	 * trigger anything here.
+	 */
+}
+#endif
+
+static const struct ethtool_ops ethtool_ops = {
+	.get_drvinfo	= netvsc_get_drvinfo,
+	.get_link	= ethtool_op_get_link,
+	.get_channels   = netvsc_get_channels,
+};
+
+static const struct net_device_ops device_ops = {
+	.ndo_open =			netvsc_open,
+	.ndo_stop =			netvsc_close,
+	.ndo_start_xmit =		netvsc_start_xmit,
+	.ndo_set_rx_mode =		netvsc_set_multicast_list,
+	.ndo_change_mtu =		netvsc_change_mtu,
+	.ndo_validate_addr =		eth_validate_addr,
+	.ndo_set_mac_address =		netvsc_set_mac_addr,
+	.ndo_select_queue =		netvsc_select_queue,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller =		netvsc_poll_controller,
+#endif
+};
+
+/*
+ * Send GARP packet to network peers after migrations.
+ * After Quick Migration, the network is not immediately operational in the
+ * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
+ * another netif_notify_peers() into a delayed work, otherwise GARP packet
+ * will not be sent after quick migration, and cause network disconnection.
+ * Also, we update the carrier status here.
+ */
+static void netvsc_link_change(struct work_struct *w)
+{
+	struct net_device_context *ndev_ctx;
+	struct net_device *net;
+	struct netvsc_device *net_device;
+	struct rndis_device *rdev;
+	bool notify, refresh = false;
+	char *argv[] = { "/etc/init.d/network", "restart", NULL };
+	char *envp[] = { "HOME=/", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
+
+	rtnl_lock();
+
+	ndev_ctx = container_of(w, struct net_device_context, dwork.work);
+	net_device = hv_get_drvdata(ndev_ctx->device_ctx);
+	rdev = net_device->extension;
+	net = net_device->ndev;
+
+	if (rdev->link_state) {
+		netif_carrier_off(net);
+		notify = false;
+	} else {
+		netif_carrier_on(net);
+		notify = true;
+		if (rdev->link_change) {
+			rdev->link_change = false;
+			refresh = true;
+		}
+	}
+
+	rtnl_unlock();
+
+	if (refresh)
+		call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
+
+	if (notify)
+		netdev_notify_peers(net);
+}
+
+
+static int netvsc_probe(struct hv_device *dev,
+			const struct hv_vmbus_device_id *dev_id)
+{
+	struct net_device *net = NULL;
+	struct net_device_context *net_device_ctx;
+	struct netvsc_device_info device_info;
+	struct netvsc_device *nvdev;
+	int ret;
+	u32 max_needed_headroom;
+
+	net = alloc_etherdev_mq(sizeof(struct net_device_context),
+				num_online_cpus());
+	if (!net)
+		return -ENOMEM;
+
+	max_needed_headroom = sizeof(struct hv_netvsc_packet) +
+			      RNDIS_AND_PPI_SIZE;
+
+	netif_carrier_off(net);
+
+	net_device_ctx = netdev_priv(net);
+	net_device_ctx->device_ctx = dev;
+	net_device_ctx->msg_enable = netif_msg_init(debug, default_msg);
+	if (netif_msg_probe(net_device_ctx))
+		netdev_dbg(net, "netvsc msg_enable: %d\n",
+			   net_device_ctx->msg_enable);
+
+	hv_set_drvdata(dev, net);
+	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
+	INIT_WORK(&net_device_ctx->work, do_set_multicast);
+
+	net->netdev_ops = &device_ops;
+
+	net->hw_features = NETIF_F_RXCSUM | NETIF_F_SG | NETIF_F_IP_CSUM |
+				NETIF_F_TSO;
+	net->features = NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_SG | NETIF_F_RXCSUM |
+			NETIF_F_IP_CSUM | NETIF_F_TSO;
+
+	net->ethtool_ops = &ethtool_ops;
+	SET_NETDEV_DEV(net, &dev->device);
+
+	/*
+	 * Request additional head room in the skb.
+	 * We will use this space to build the rndis
+	 * heaser and other state we need to maintain.
+	 */
+	net->needed_headroom = max_needed_headroom;
+
+	/* Notify the netvsc driver of the new device */
+	device_info.ring_size = ring_size;
+	ret = rndis_filter_device_add(dev, &device_info);
+	if (ret != 0) {
+		netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
+		free_netdev(net);
+		hv_set_drvdata(dev, NULL);
+		return ret;
+	}
+	memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
+
+	nvdev = hv_get_drvdata(dev);
+	netif_set_real_num_tx_queues(net, nvdev->num_chn);
+	netif_set_real_num_rx_queues(net, nvdev->num_chn);
+
+	ret = register_netdev(net);
+	if (ret != 0) {
+		pr_err("Unable to register netdev.\n");
+		rndis_filter_device_remove(dev);
+		free_netdev(net);
+	} else {
+		schedule_delayed_work(&net_device_ctx->dwork, 0);
+	}
+
+	return ret;
+}
+
+static int netvsc_remove(struct hv_device *dev)
+{
+	struct net_device *net;
+	struct net_device_context *ndev_ctx;
+	struct netvsc_device *net_device;
+
+	net_device = hv_get_drvdata(dev);
+	net = net_device->ndev;
+
+	if (net == NULL) {
+		dev_err(&dev->device, "No net device to remove\n");
+		return 0;
+	}
+
+	net_device->start_remove = true;
+
+	ndev_ctx = netdev_priv(net);
+	cancel_delayed_work_sync(&ndev_ctx->dwork);
+	cancel_work_sync(&ndev_ctx->work);
+
+	/* Stop outbound asap */
+	netif_tx_disable(net);
+
+	unregister_netdev(net);
+
+	/*
+	 * Call to the vsc driver to let it know that the device is being
+	 * removed
+	 */
+	rndis_filter_device_remove(dev);
+
+	free_netdev(net);
+	return 0;
+}
+
+static const struct hv_vmbus_device_id id_table[] = {
+	/* Network guid */
+	{ HV_NIC_GUID, },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(vmbus, id_table);
+
+/* The one and only one */
+static struct  hv_driver netvsc_drv = {
+	.name = KBUILD_MODNAME,
+	.id_table = id_table,
+	.probe = netvsc_probe,
+	.remove = netvsc_remove,
+};
+
+static void __exit netvsc_drv_exit(void)
+{
+	vmbus_driver_unregister(&netvsc_drv);
+}
+
+static int __init netvsc_drv_init(void)
+{
+	if (ring_size < RING_SIZE_MIN) {
+		ring_size = RING_SIZE_MIN;
+		pr_info("Increased ring_size to %d (min allowed)\n",
+			ring_size);
+	}
+	return vmbus_driver_register(&netvsc_drv);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
+
+module_init(netvsc_drv_init);
+module_exit(netvsc_drv_exit);
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
new file mode 100644
index 000000000..9118cea91
--- /dev/null
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -0,0 +1,1192 @@
+/*
+ * Copyright (c) 2009, 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, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ */
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/highmem.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/if_ether.h>
+#include <linux/netdevice.h>
+#include <linux/if_vlan.h>
+#include <linux/nls.h>
+
+#include "hyperv_net.h"
+
+
+#define RNDIS_EXT_LEN PAGE_SIZE
+struct rndis_request {
+	struct list_head list_ent;
+	struct completion  wait_event;
+
+	struct rndis_message response_msg;
+	/*
+	 * The buffer for extended info after the RNDIS response message. It's
+	 * referenced based on the data offset in the RNDIS message. Its size
+	 * is enough for current needs, and should be sufficient for the near
+	 * future.
+	 */
+	u8 response_ext[RNDIS_EXT_LEN];
+
+	/* Simplify allocation by having a netvsc packet inline */
+	struct hv_netvsc_packet	pkt;
+
+	struct rndis_message request_msg;
+	/*
+	 * The buffer for the extended info after the RNDIS request message.
+	 * It is referenced and sized in a similar way as response_ext.
+	 */
+	u8 request_ext[RNDIS_EXT_LEN];
+};
+
+static struct rndis_device *get_rndis_device(void)
+{
+	struct rndis_device *device;
+
+	device = kzalloc(sizeof(struct rndis_device), GFP_KERNEL);
+	if (!device)
+		return NULL;
+
+	spin_lock_init(&device->request_lock);
+
+	INIT_LIST_HEAD(&device->req_list);
+
+	device->state = RNDIS_DEV_UNINITIALIZED;
+
+	return device;
+}
+
+static struct rndis_request *get_rndis_request(struct rndis_device *dev,
+					     u32 msg_type,
+					     u32 msg_len)
+{
+	struct rndis_request *request;
+	struct rndis_message *rndis_msg;
+	struct rndis_set_request *set;
+	unsigned long flags;
+
+	request = kzalloc(sizeof(struct rndis_request), GFP_KERNEL);
+	if (!request)
+		return NULL;
+
+	init_completion(&request->wait_event);
+
+	rndis_msg = &request->request_msg;
+	rndis_msg->ndis_msg_type = msg_type;
+	rndis_msg->msg_len = msg_len;
+
+	request->pkt.q_idx = 0;
+
+	/*
+	 * Set the request id. This field is always after the rndis header for
+	 * request/response packet types so we just used the SetRequest as a
+	 * template
+	 */
+	set = &rndis_msg->msg.set_req;
+	set->req_id = atomic_inc_return(&dev->new_req_id);
+
+	/* Add to the request list */
+	spin_lock_irqsave(&dev->request_lock, flags);
+	list_add_tail(&request->list_ent, &dev->req_list);
+	spin_unlock_irqrestore(&dev->request_lock, flags);
+
+	return request;
+}
+
+static void put_rndis_request(struct rndis_device *dev,
+			    struct rndis_request *req)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->request_lock, flags);
+	list_del(&req->list_ent);
+	spin_unlock_irqrestore(&dev->request_lock, flags);
+
+	kfree(req);
+}
+
+static void dump_rndis_message(struct hv_device *hv_dev,
+			struct rndis_message *rndis_msg)
+{
+	struct net_device *netdev;
+	struct netvsc_device *net_device;
+
+	net_device = hv_get_drvdata(hv_dev);
+	netdev = net_device->ndev;
+
+	switch (rndis_msg->ndis_msg_type) {
+	case RNDIS_MSG_PACKET:
+		netdev_dbg(netdev, "RNDIS_MSG_PACKET (len %u, "
+			   "data offset %u data len %u, # oob %u, "
+			   "oob offset %u, oob len %u, pkt offset %u, "
+			   "pkt len %u\n",
+			   rndis_msg->msg_len,
+			   rndis_msg->msg.pkt.data_offset,
+			   rndis_msg->msg.pkt.data_len,
+			   rndis_msg->msg.pkt.num_oob_data_elements,
+			   rndis_msg->msg.pkt.oob_data_offset,
+			   rndis_msg->msg.pkt.oob_data_len,
+			   rndis_msg->msg.pkt.per_pkt_info_offset,
+			   rndis_msg->msg.pkt.per_pkt_info_len);
+		break;
+
+	case RNDIS_MSG_INIT_C:
+		netdev_dbg(netdev, "RNDIS_MSG_INIT_C "
+			"(len %u, id 0x%x, status 0x%x, major %d, minor %d, "
+			"device flags %d, max xfer size 0x%x, max pkts %u, "
+			"pkt aligned %u)\n",
+			rndis_msg->msg_len,
+			rndis_msg->msg.init_complete.req_id,
+			rndis_msg->msg.init_complete.status,
+			rndis_msg->msg.init_complete.major_ver,
+			rndis_msg->msg.init_complete.minor_ver,
+			rndis_msg->msg.init_complete.dev_flags,
+			rndis_msg->msg.init_complete.max_xfer_size,
+			rndis_msg->msg.init_complete.
+			   max_pkt_per_msg,
+			rndis_msg->msg.init_complete.
+			   pkt_alignment_factor);
+		break;
+
+	case RNDIS_MSG_QUERY_C:
+		netdev_dbg(netdev, "RNDIS_MSG_QUERY_C "
+			"(len %u, id 0x%x, status 0x%x, buf len %u, "
+			"buf offset %u)\n",
+			rndis_msg->msg_len,
+			rndis_msg->msg.query_complete.req_id,
+			rndis_msg->msg.query_complete.status,
+			rndis_msg->msg.query_complete.
+			   info_buflen,
+			rndis_msg->msg.query_complete.
+			   info_buf_offset);
+		break;
+
+	case RNDIS_MSG_SET_C:
+		netdev_dbg(netdev,
+			"RNDIS_MSG_SET_C (len %u, id 0x%x, status 0x%x)\n",
+			rndis_msg->msg_len,
+			rndis_msg->msg.set_complete.req_id,
+			rndis_msg->msg.set_complete.status);
+		break;
+
+	case RNDIS_MSG_INDICATE:
+		netdev_dbg(netdev, "RNDIS_MSG_INDICATE "
+			"(len %u, status 0x%x, buf len %u, buf offset %u)\n",
+			rndis_msg->msg_len,
+			rndis_msg->msg.indicate_status.status,
+			rndis_msg->msg.indicate_status.status_buflen,
+			rndis_msg->msg.indicate_status.status_buf_offset);
+		break;
+
+	default:
+		netdev_dbg(netdev, "0x%x (len %u)\n",
+			rndis_msg->ndis_msg_type,
+			rndis_msg->msg_len);
+		break;
+	}
+}
+
+static int rndis_filter_send_request(struct rndis_device *dev,
+				  struct rndis_request *req)
+{
+	int ret;
+	struct hv_netvsc_packet *packet;
+	struct hv_page_buffer page_buf[2];
+
+	/* Setup the packet to send it */
+	packet = &req->pkt;
+
+	packet->is_data_pkt = false;
+	packet->total_data_buflen = req->request_msg.msg_len;
+	packet->page_buf_cnt = 1;
+	packet->page_buf = page_buf;
+
+	packet->page_buf[0].pfn = virt_to_phys(&req->request_msg) >>
+					PAGE_SHIFT;
+	packet->page_buf[0].len = req->request_msg.msg_len;
+	packet->page_buf[0].offset =
+		(unsigned long)&req->request_msg & (PAGE_SIZE - 1);
+
+	/* Add one page_buf when request_msg crossing page boundary */
+	if (packet->page_buf[0].offset + packet->page_buf[0].len > PAGE_SIZE) {
+		packet->page_buf_cnt++;
+		packet->page_buf[0].len = PAGE_SIZE -
+			packet->page_buf[0].offset;
+		packet->page_buf[1].pfn = virt_to_phys((void *)&req->request_msg
+			+ packet->page_buf[0].len) >> PAGE_SHIFT;
+		packet->page_buf[1].offset = 0;
+		packet->page_buf[1].len = req->request_msg.msg_len -
+			packet->page_buf[0].len;
+	}
+
+	packet->send_completion = NULL;
+	packet->xmit_more = false;
+
+	ret = netvsc_send(dev->net_dev->dev, packet);
+	return ret;
+}
+
+static void rndis_set_link_state(struct rndis_device *rdev,
+				 struct rndis_request *request)
+{
+	u32 link_status;
+	struct rndis_query_complete *query_complete;
+
+	query_complete = &request->response_msg.msg.query_complete;
+
+	if (query_complete->status == RNDIS_STATUS_SUCCESS &&
+	    query_complete->info_buflen == sizeof(u32)) {
+		memcpy(&link_status, (void *)((unsigned long)query_complete +
+		       query_complete->info_buf_offset), sizeof(u32));
+		rdev->link_state = link_status != 0;
+	}
+}
+
+static void rndis_filter_receive_response(struct rndis_device *dev,
+				       struct rndis_message *resp)
+{
+	struct rndis_request *request = NULL;
+	bool found = false;
+	unsigned long flags;
+	struct net_device *ndev;
+
+	ndev = dev->net_dev->ndev;
+
+	spin_lock_irqsave(&dev->request_lock, flags);
+	list_for_each_entry(request, &dev->req_list, list_ent) {
+		/*
+		 * All request/response message contains RequestId as the 1st
+		 * field
+		 */
+		if (request->request_msg.msg.init_req.req_id
+		    == resp->msg.init_complete.req_id) {
+			found = true;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&dev->request_lock, flags);
+
+	if (found) {
+		if (resp->msg_len <=
+		    sizeof(struct rndis_message) + RNDIS_EXT_LEN) {
+			memcpy(&request->response_msg, resp,
+			       resp->msg_len);
+			if (request->request_msg.ndis_msg_type ==
+			    RNDIS_MSG_QUERY && request->request_msg.msg.
+			    query_req.oid == RNDIS_OID_GEN_MEDIA_CONNECT_STATUS)
+				rndis_set_link_state(dev, request);
+		} else {
+			netdev_err(ndev,
+				"rndis response buffer overflow "
+				"detected (size %u max %zu)\n",
+				resp->msg_len,
+				sizeof(struct rndis_message));
+
+			if (resp->ndis_msg_type ==
+			    RNDIS_MSG_RESET_C) {
+				/* does not have a request id field */
+				request->response_msg.msg.reset_complete.
+					status = RNDIS_STATUS_BUFFER_OVERFLOW;
+			} else {
+				request->response_msg.msg.
+				init_complete.status =
+					RNDIS_STATUS_BUFFER_OVERFLOW;
+			}
+		}
+
+		complete(&request->wait_event);
+	} else {
+		netdev_err(ndev,
+			"no rndis request found for this response "
+			"(id 0x%x res type 0x%x)\n",
+			resp->msg.init_complete.req_id,
+			resp->ndis_msg_type);
+	}
+}
+
+/*
+ * Get the Per-Packet-Info with the specified type
+ * return NULL if not found.
+ */
+static inline void *rndis_get_ppi(struct rndis_packet *rpkt, u32 type)
+{
+	struct rndis_per_packet_info *ppi;
+	int len;
+
+	if (rpkt->per_pkt_info_offset == 0)
+		return NULL;
+
+	ppi = (struct rndis_per_packet_info *)((ulong)rpkt +
+		rpkt->per_pkt_info_offset);
+	len = rpkt->per_pkt_info_len;
+
+	while (len > 0) {
+		if (ppi->type == type)
+			return (void *)((ulong)ppi + ppi->ppi_offset);
+		len -= ppi->size;
+		ppi = (struct rndis_per_packet_info *)((ulong)ppi + ppi->size);
+	}
+
+	return NULL;
+}
+
+static void rndis_filter_receive_data(struct rndis_device *dev,
+				   struct rndis_message *msg,
+				   struct hv_netvsc_packet *pkt)
+{
+	struct rndis_packet *rndis_pkt;
+	u32 data_offset;
+	struct ndis_pkt_8021q_info *vlan;
+	struct ndis_tcp_ip_checksum_info *csum_info;
+
+	rndis_pkt = &msg->msg.pkt;
+
+	/* Remove the rndis header and pass it back up the stack */
+	data_offset = RNDIS_HEADER_SIZE + rndis_pkt->data_offset;
+
+	pkt->total_data_buflen -= data_offset;
+
+	/*
+	 * Make sure we got a valid RNDIS message, now total_data_buflen
+	 * should be the data packet size plus the trailer padding size
+	 */
+	if (pkt->total_data_buflen < rndis_pkt->data_len) {
+		netdev_err(dev->net_dev->ndev, "rndis message buffer "
+			   "overflow detected (got %u, min %u)"
+			   "...dropping this message!\n",
+			   pkt->total_data_buflen, rndis_pkt->data_len);
+		return;
+	}
+
+	/*
+	 * Remove the rndis trailer padding from rndis packet message
+	 * rndis_pkt->data_len tell us the real data length, we only copy
+	 * the data packet to the stack, without the rndis trailer padding
+	 */
+	pkt->total_data_buflen = rndis_pkt->data_len;
+	pkt->data = (void *)((unsigned long)pkt->data + data_offset);
+
+	vlan = rndis_get_ppi(rndis_pkt, IEEE_8021Q_INFO);
+	if (vlan) {
+		pkt->vlan_tci = VLAN_TAG_PRESENT | vlan->vlanid |
+			(vlan->pri << VLAN_PRIO_SHIFT);
+	} else {
+		pkt->vlan_tci = 0;
+	}
+
+	csum_info = rndis_get_ppi(rndis_pkt, TCPIP_CHKSUM_PKTINFO);
+	netvsc_recv_callback(dev->net_dev->dev, pkt, csum_info);
+}
+
+int rndis_filter_receive(struct hv_device *dev,
+				struct hv_netvsc_packet	*pkt)
+{
+	struct netvsc_device *net_dev = hv_get_drvdata(dev);
+	struct rndis_device *rndis_dev;
+	struct rndis_message *rndis_msg;
+	struct net_device *ndev;
+	int ret = 0;
+
+	if (!net_dev) {
+		ret = -EINVAL;
+		goto exit;
+	}
+
+	ndev = net_dev->ndev;
+
+	/* Make sure the rndis device state is initialized */
+	if (!net_dev->extension) {
+		netdev_err(ndev, "got rndis message but no rndis device - "
+			  "dropping this message!\n");
+		ret = -ENODEV;
+		goto exit;
+	}
+
+	rndis_dev = (struct rndis_device *)net_dev->extension;
+	if (rndis_dev->state == RNDIS_DEV_UNINITIALIZED) {
+		netdev_err(ndev, "got rndis message but rndis device "
+			   "uninitialized...dropping this message!\n");
+		ret = -ENODEV;
+		goto exit;
+	}
+
+	rndis_msg = pkt->data;
+
+	if (netif_msg_rx_err(net_dev->nd_ctx))
+		dump_rndis_message(dev, rndis_msg);
+
+	switch (rndis_msg->ndis_msg_type) {
+	case RNDIS_MSG_PACKET:
+		/* data msg */
+		rndis_filter_receive_data(rndis_dev, rndis_msg, pkt);
+		break;
+
+	case RNDIS_MSG_INIT_C:
+	case RNDIS_MSG_QUERY_C:
+	case RNDIS_MSG_SET_C:
+		/* completion msgs */
+		rndis_filter_receive_response(rndis_dev, rndis_msg);
+		break;
+
+	case RNDIS_MSG_INDICATE:
+		/* notification msgs */
+		netvsc_linkstatus_callback(dev, rndis_msg);
+		break;
+	default:
+		netdev_err(ndev,
+			"unhandled rndis message (type %u len %u)\n",
+			   rndis_msg->ndis_msg_type,
+			   rndis_msg->msg_len);
+		break;
+	}
+
+exit:
+	if (ret != 0)
+		pkt->status = NVSP_STAT_FAIL;
+
+	return ret;
+}
+
+static int rndis_filter_query_device(struct rndis_device *dev, u32 oid,
+				  void *result, u32 *result_size)
+{
+	struct rndis_request *request;
+	u32 inresult_size = *result_size;
+	struct rndis_query_request *query;
+	struct rndis_query_complete *query_complete;
+	int ret = 0;
+	unsigned long t;
+
+	if (!result)
+		return -EINVAL;
+
+	*result_size = 0;
+	request = get_rndis_request(dev, RNDIS_MSG_QUERY,
+			RNDIS_MESSAGE_SIZE(struct rndis_query_request));
+	if (!request) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	/* Setup the rndis query */
+	query = &request->request_msg.msg.query_req;
+	query->oid = oid;
+	query->info_buf_offset = sizeof(struct rndis_query_request);
+	query->info_buflen = 0;
+	query->dev_vc_handle = 0;
+
+	if (oid == OID_GEN_RECEIVE_SCALE_CAPABILITIES) {
+		struct ndis_recv_scale_cap *cap;
+
+		request->request_msg.msg_len +=
+			sizeof(struct ndis_recv_scale_cap);
+		query->info_buflen = sizeof(struct ndis_recv_scale_cap);
+		cap = (struct ndis_recv_scale_cap *)((unsigned long)query +
+						     query->info_buf_offset);
+		cap->hdr.type = NDIS_OBJECT_TYPE_RSS_CAPABILITIES;
+		cap->hdr.rev = NDIS_RECEIVE_SCALE_CAPABILITIES_REVISION_2;
+		cap->hdr.size = sizeof(struct ndis_recv_scale_cap);
+	}
+
+	ret = rndis_filter_send_request(dev, request);
+	if (ret != 0)
+		goto cleanup;
+
+	t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+	if (t == 0) {
+		ret = -ETIMEDOUT;
+		goto cleanup;
+	}
+
+	/* Copy the response back */
+	query_complete = &request->response_msg.msg.query_complete;
+
+	if (query_complete->info_buflen > inresult_size) {
+		ret = -1;
+		goto cleanup;
+	}
+
+	memcpy(result,
+	       (void *)((unsigned long)query_complete +
+			 query_complete->info_buf_offset),
+	       query_complete->info_buflen);
+
+	*result_size = query_complete->info_buflen;
+
+cleanup:
+	if (request)
+		put_rndis_request(dev, request);
+
+	return ret;
+}
+
+static int rndis_filter_query_device_mac(struct rndis_device *dev)
+{
+	u32 size = ETH_ALEN;
+
+	return rndis_filter_query_device(dev,
+				      RNDIS_OID_802_3_PERMANENT_ADDRESS,
+				      dev->hw_mac_adr, &size);
+}
+
+#define NWADR_STR "NetworkAddress"
+#define NWADR_STRLEN 14
+
+int rndis_filter_set_device_mac(struct hv_device *hdev, char *mac)
+{
+	struct netvsc_device *nvdev = hv_get_drvdata(hdev);
+	struct rndis_device *rdev = nvdev->extension;
+	struct net_device *ndev = nvdev->ndev;
+	struct rndis_request *request;
+	struct rndis_set_request *set;
+	struct rndis_config_parameter_info *cpi;
+	wchar_t *cfg_nwadr, *cfg_mac;
+	struct rndis_set_complete *set_complete;
+	char macstr[2*ETH_ALEN+1];
+	u32 extlen = sizeof(struct rndis_config_parameter_info) +
+		2*NWADR_STRLEN + 4*ETH_ALEN;
+	int ret;
+	unsigned long t;
+
+	request = get_rndis_request(rdev, RNDIS_MSG_SET,
+		RNDIS_MESSAGE_SIZE(struct rndis_set_request) + extlen);
+	if (!request)
+		return -ENOMEM;
+
+	set = &request->request_msg.msg.set_req;
+	set->oid = RNDIS_OID_GEN_RNDIS_CONFIG_PARAMETER;
+	set->info_buflen = extlen;
+	set->info_buf_offset = sizeof(struct rndis_set_request);
+	set->dev_vc_handle = 0;
+
+	cpi = (struct rndis_config_parameter_info *)((ulong)set +
+		set->info_buf_offset);
+	cpi->parameter_name_offset =
+		sizeof(struct rndis_config_parameter_info);
+	/* Multiply by 2 because host needs 2 bytes (utf16) for each char */
+	cpi->parameter_name_length = 2*NWADR_STRLEN;
+	cpi->parameter_type = RNDIS_CONFIG_PARAM_TYPE_STRING;
+	cpi->parameter_value_offset =
+		cpi->parameter_name_offset + cpi->parameter_name_length;
+	/* Multiply by 4 because each MAC byte displayed as 2 utf16 chars */
+	cpi->parameter_value_length = 4*ETH_ALEN;
+
+	cfg_nwadr = (wchar_t *)((ulong)cpi + cpi->parameter_name_offset);
+	cfg_mac = (wchar_t *)((ulong)cpi + cpi->parameter_value_offset);
+	ret = utf8s_to_utf16s(NWADR_STR, NWADR_STRLEN, UTF16_HOST_ENDIAN,
+			      cfg_nwadr, NWADR_STRLEN);
+	if (ret < 0)
+		goto cleanup;
+	snprintf(macstr, 2*ETH_ALEN+1, "%pm", mac);
+	ret = utf8s_to_utf16s(macstr, 2*ETH_ALEN, UTF16_HOST_ENDIAN,
+			      cfg_mac, 2*ETH_ALEN);
+	if (ret < 0)
+		goto cleanup;
+
+	ret = rndis_filter_send_request(rdev, request);
+	if (ret != 0)
+		goto cleanup;
+
+	t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+	if (t == 0) {
+		netdev_err(ndev, "timeout before we got a set response...\n");
+		/*
+		 * can't put_rndis_request, since we may still receive a
+		 * send-completion.
+		 */
+		return -EBUSY;
+	} else {
+		set_complete = &request->response_msg.msg.set_complete;
+		if (set_complete->status != RNDIS_STATUS_SUCCESS) {
+			netdev_err(ndev, "Fail to set MAC on host side:0x%x\n",
+				   set_complete->status);
+			ret = -EINVAL;
+		}
+	}
+
+cleanup:
+	put_rndis_request(rdev, request);
+	return ret;
+}
+
+static int
+rndis_filter_set_offload_params(struct hv_device *hdev,
+				struct ndis_offload_params *req_offloads)
+{
+	struct netvsc_device *nvdev = hv_get_drvdata(hdev);
+	struct rndis_device *rdev = nvdev->extension;
+	struct net_device *ndev = nvdev->ndev;
+	struct rndis_request *request;
+	struct rndis_set_request *set;
+	struct ndis_offload_params *offload_params;
+	struct rndis_set_complete *set_complete;
+	u32 extlen = sizeof(struct ndis_offload_params);
+	int ret;
+	unsigned long t;
+	u32 vsp_version = nvdev->nvsp_version;
+
+	if (vsp_version <= NVSP_PROTOCOL_VERSION_4) {
+		extlen = VERSION_4_OFFLOAD_SIZE;
+		/* On NVSP_PROTOCOL_VERSION_4 and below, we do not support
+		 * UDP checksum offload.
+		 */
+		req_offloads->udp_ip_v4_csum = 0;
+		req_offloads->udp_ip_v6_csum = 0;
+	}
+
+	request = get_rndis_request(rdev, RNDIS_MSG_SET,
+		RNDIS_MESSAGE_SIZE(struct rndis_set_request) + extlen);
+	if (!request)
+		return -ENOMEM;
+
+	set = &request->request_msg.msg.set_req;
+	set->oid = OID_TCP_OFFLOAD_PARAMETERS;
+	set->info_buflen = extlen;
+	set->info_buf_offset = sizeof(struct rndis_set_request);
+	set->dev_vc_handle = 0;
+
+	offload_params = (struct ndis_offload_params *)((ulong)set +
+				set->info_buf_offset);
+	*offload_params = *req_offloads;
+	offload_params->header.type = NDIS_OBJECT_TYPE_DEFAULT;
+	offload_params->header.revision = NDIS_OFFLOAD_PARAMETERS_REVISION_3;
+	offload_params->header.size = extlen;
+
+	ret = rndis_filter_send_request(rdev, request);
+	if (ret != 0)
+		goto cleanup;
+
+	t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+	if (t == 0) {
+		netdev_err(ndev, "timeout before we got aOFFLOAD set response...\n");
+		/* can't put_rndis_request, since we may still receive a
+		 * send-completion.
+		 */
+		return -EBUSY;
+	} else {
+		set_complete = &request->response_msg.msg.set_complete;
+		if (set_complete->status != RNDIS_STATUS_SUCCESS) {
+			netdev_err(ndev, "Fail to set offload on host side:0x%x\n",
+				   set_complete->status);
+			ret = -EINVAL;
+		}
+	}
+
+cleanup:
+	put_rndis_request(rdev, request);
+	return ret;
+}
+
+u8 netvsc_hash_key[HASH_KEYLEN] = {
+	0x6d, 0x5a, 0x56, 0xda, 0x25, 0x5b, 0x0e, 0xc2,
+	0x41, 0x67, 0x25, 0x3d, 0x43, 0xa3, 0x8f, 0xb0,
+	0xd0, 0xca, 0x2b, 0xcb, 0xae, 0x7b, 0x30, 0xb4,
+	0x77, 0xcb, 0x2d, 0xa3, 0x80, 0x30, 0xf2, 0x0c,
+	0x6a, 0x42, 0xb7, 0x3b, 0xbe, 0xac, 0x01, 0xfa
+};
+
+static int rndis_filter_set_rss_param(struct rndis_device *rdev, int num_queue)
+{
+	struct net_device *ndev = rdev->net_dev->ndev;
+	struct rndis_request *request;
+	struct rndis_set_request *set;
+	struct rndis_set_complete *set_complete;
+	u32 extlen = sizeof(struct ndis_recv_scale_param) +
+		     4*ITAB_NUM + HASH_KEYLEN;
+	struct ndis_recv_scale_param *rssp;
+	u32 *itab;
+	u8 *keyp;
+	int i, ret;
+	unsigned long t;
+
+	request = get_rndis_request(
+			rdev, RNDIS_MSG_SET,
+			RNDIS_MESSAGE_SIZE(struct rndis_set_request) + extlen);
+	if (!request)
+		return -ENOMEM;
+
+	set = &request->request_msg.msg.set_req;
+	set->oid = OID_GEN_RECEIVE_SCALE_PARAMETERS;
+	set->info_buflen = extlen;
+	set->info_buf_offset = sizeof(struct rndis_set_request);
+	set->dev_vc_handle = 0;
+
+	rssp = (struct ndis_recv_scale_param *)(set + 1);
+	rssp->hdr.type = NDIS_OBJECT_TYPE_RSS_PARAMETERS;
+	rssp->hdr.rev = NDIS_RECEIVE_SCALE_PARAMETERS_REVISION_2;
+	rssp->hdr.size = sizeof(struct ndis_recv_scale_param);
+	rssp->flag = 0;
+	rssp->hashinfo = NDIS_HASH_FUNC_TOEPLITZ | NDIS_HASH_IPV4 |
+			 NDIS_HASH_TCP_IPV4 | NDIS_HASH_IPV6 |
+			 NDIS_HASH_TCP_IPV6;
+	rssp->indirect_tabsize = 4*ITAB_NUM;
+	rssp->indirect_taboffset = sizeof(struct ndis_recv_scale_param);
+	rssp->hashkey_size = HASH_KEYLEN;
+	rssp->kashkey_offset = rssp->indirect_taboffset +
+			       rssp->indirect_tabsize;
+
+	/* Set indirection table entries */
+	itab = (u32 *)(rssp + 1);
+	for (i = 0; i < ITAB_NUM; i++)
+		itab[i] = i % num_queue;
+
+	/* Set hask key values */
+	keyp = (u8 *)((unsigned long)rssp + rssp->kashkey_offset);
+	for (i = 0; i < HASH_KEYLEN; i++)
+		keyp[i] = netvsc_hash_key[i];
+
+
+	ret = rndis_filter_send_request(rdev, request);
+	if (ret != 0)
+		goto cleanup;
+
+	t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+	if (t == 0) {
+		netdev_err(ndev, "timeout before we got a set response...\n");
+		/* can't put_rndis_request, since we may still receive a
+		 * send-completion.
+		 */
+		return -ETIMEDOUT;
+	} else {
+		set_complete = &request->response_msg.msg.set_complete;
+		if (set_complete->status != RNDIS_STATUS_SUCCESS) {
+			netdev_err(ndev, "Fail to set RSS parameters:0x%x\n",
+				   set_complete->status);
+			ret = -EINVAL;
+		}
+	}
+
+cleanup:
+	put_rndis_request(rdev, request);
+	return ret;
+}
+
+
+static int rndis_filter_query_device_link_status(struct rndis_device *dev)
+{
+	u32 size = sizeof(u32);
+	u32 link_status;
+	int ret;
+
+	ret = rndis_filter_query_device(dev,
+				      RNDIS_OID_GEN_MEDIA_CONNECT_STATUS,
+				      &link_status, &size);
+
+	return ret;
+}
+
+int rndis_filter_set_packet_filter(struct rndis_device *dev, u32 new_filter)
+{
+	struct rndis_request *request;
+	struct rndis_set_request *set;
+	struct rndis_set_complete *set_complete;
+	u32 status;
+	int ret;
+	unsigned long t;
+	struct net_device *ndev;
+
+	ndev = dev->net_dev->ndev;
+
+	request = get_rndis_request(dev, RNDIS_MSG_SET,
+			RNDIS_MESSAGE_SIZE(struct rndis_set_request) +
+			sizeof(u32));
+	if (!request) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	/* Setup the rndis set */
+	set = &request->request_msg.msg.set_req;
+	set->oid = RNDIS_OID_GEN_CURRENT_PACKET_FILTER;
+	set->info_buflen = sizeof(u32);
+	set->info_buf_offset = sizeof(struct rndis_set_request);
+
+	memcpy((void *)(unsigned long)set + sizeof(struct rndis_set_request),
+	       &new_filter, sizeof(u32));
+
+	ret = rndis_filter_send_request(dev, request);
+	if (ret != 0)
+		goto cleanup;
+
+	t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+
+	if (t == 0) {
+		netdev_err(ndev,
+			"timeout before we got a set response...\n");
+		ret = -ETIMEDOUT;
+		/*
+		 * We can't deallocate the request since we may still receive a
+		 * send completion for it.
+		 */
+		goto exit;
+	} else {
+		set_complete = &request->response_msg.msg.set_complete;
+		status = set_complete->status;
+	}
+
+cleanup:
+	if (request)
+		put_rndis_request(dev, request);
+exit:
+	return ret;
+}
+
+
+static int rndis_filter_init_device(struct rndis_device *dev)
+{
+	struct rndis_request *request;
+	struct rndis_initialize_request *init;
+	struct rndis_initialize_complete *init_complete;
+	u32 status;
+	int ret;
+	unsigned long t;
+	struct netvsc_device *nvdev = dev->net_dev;
+
+	request = get_rndis_request(dev, RNDIS_MSG_INIT,
+			RNDIS_MESSAGE_SIZE(struct rndis_initialize_request));
+	if (!request) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	/* Setup the rndis set */
+	init = &request->request_msg.msg.init_req;
+	init->major_ver = RNDIS_MAJOR_VERSION;
+	init->minor_ver = RNDIS_MINOR_VERSION;
+	init->max_xfer_size = 0x4000;
+
+	dev->state = RNDIS_DEV_INITIALIZING;
+
+	ret = rndis_filter_send_request(dev, request);
+	if (ret != 0) {
+		dev->state = RNDIS_DEV_UNINITIALIZED;
+		goto cleanup;
+	}
+
+
+	t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+
+	if (t == 0) {
+		ret = -ETIMEDOUT;
+		goto cleanup;
+	}
+
+	init_complete = &request->response_msg.msg.init_complete;
+	status = init_complete->status;
+	if (status == RNDIS_STATUS_SUCCESS) {
+		dev->state = RNDIS_DEV_INITIALIZED;
+		nvdev->max_pkt = init_complete->max_pkt_per_msg;
+		nvdev->pkt_align = 1 << init_complete->pkt_alignment_factor;
+		ret = 0;
+	} else {
+		dev->state = RNDIS_DEV_UNINITIALIZED;
+		ret = -EINVAL;
+	}
+
+cleanup:
+	if (request)
+		put_rndis_request(dev, request);
+
+	return ret;
+}
+
+static void rndis_filter_halt_device(struct rndis_device *dev)
+{
+	struct rndis_request *request;
+	struct rndis_halt_request *halt;
+	struct netvsc_device *nvdev = dev->net_dev;
+	struct hv_device *hdev = nvdev->dev;
+	ulong flags;
+
+	/* Attempt to do a rndis device halt */
+	request = get_rndis_request(dev, RNDIS_MSG_HALT,
+				RNDIS_MESSAGE_SIZE(struct rndis_halt_request));
+	if (!request)
+		goto cleanup;
+
+	/* Setup the rndis set */
+	halt = &request->request_msg.msg.halt_req;
+	halt->req_id = atomic_inc_return(&dev->new_req_id);
+
+	/* Ignore return since this msg is optional. */
+	rndis_filter_send_request(dev, request);
+
+	dev->state = RNDIS_DEV_UNINITIALIZED;
+
+cleanup:
+	spin_lock_irqsave(&hdev->channel->inbound_lock, flags);
+	nvdev->destroy = true;
+	spin_unlock_irqrestore(&hdev->channel->inbound_lock, flags);
+
+	/* Wait for all send completions */
+	wait_event(nvdev->wait_drain,
+		atomic_read(&nvdev->num_outstanding_sends) == 0);
+
+	if (request)
+		put_rndis_request(dev, request);
+	return;
+}
+
+static int rndis_filter_open_device(struct rndis_device *dev)
+{
+	int ret;
+
+	if (dev->state != RNDIS_DEV_INITIALIZED)
+		return 0;
+
+	ret = rndis_filter_set_packet_filter(dev,
+					 NDIS_PACKET_TYPE_BROADCAST |
+					 NDIS_PACKET_TYPE_ALL_MULTICAST |
+					 NDIS_PACKET_TYPE_DIRECTED);
+	if (ret == 0)
+		dev->state = RNDIS_DEV_DATAINITIALIZED;
+
+	return ret;
+}
+
+static int rndis_filter_close_device(struct rndis_device *dev)
+{
+	int ret;
+
+	if (dev->state != RNDIS_DEV_DATAINITIALIZED)
+		return 0;
+
+	ret = rndis_filter_set_packet_filter(dev, 0);
+	if (ret == -ENODEV)
+		ret = 0;
+
+	if (ret == 0)
+		dev->state = RNDIS_DEV_INITIALIZED;
+
+	return ret;
+}
+
+static void netvsc_sc_open(struct vmbus_channel *new_sc)
+{
+	struct netvsc_device *nvscdev;
+	u16 chn_index = new_sc->offermsg.offer.sub_channel_index;
+	int ret;
+
+	nvscdev = hv_get_drvdata(new_sc->primary_channel->device_obj);
+
+	if (chn_index >= nvscdev->num_chn)
+		return;
+
+	set_per_channel_state(new_sc, nvscdev->sub_cb_buf + (chn_index - 1) *
+			      NETVSC_PACKET_SIZE);
+
+	ret = vmbus_open(new_sc, nvscdev->ring_size * PAGE_SIZE,
+			 nvscdev->ring_size * PAGE_SIZE, NULL, 0,
+			 netvsc_channel_cb, new_sc);
+
+	if (ret == 0)
+		nvscdev->chn_table[chn_index] = new_sc;
+}
+
+int rndis_filter_device_add(struct hv_device *dev,
+				  void *additional_info)
+{
+	int ret;
+	struct netvsc_device *net_device;
+	struct rndis_device *rndis_device;
+	struct netvsc_device_info *device_info = additional_info;
+	struct ndis_offload_params offloads;
+	struct nvsp_message *init_packet;
+	unsigned long t;
+	struct ndis_recv_scale_cap rsscap;
+	u32 rsscap_size = sizeof(struct ndis_recv_scale_cap);
+	u32 mtu, size;
+
+	rndis_device = get_rndis_device();
+	if (!rndis_device)
+		return -ENODEV;
+
+	/*
+	 * Let the inner driver handle this first to create the netvsc channel
+	 * NOTE! Once the channel is created, we may get a receive callback
+	 * (RndisFilterOnReceive()) before this call is completed
+	 */
+	ret = netvsc_device_add(dev, additional_info);
+	if (ret != 0) {
+		kfree(rndis_device);
+		return ret;
+	}
+
+
+	/* Initialize the rndis device */
+	net_device = hv_get_drvdata(dev);
+	net_device->max_chn = 1;
+	net_device->num_chn = 1;
+
+	net_device->extension = rndis_device;
+	rndis_device->net_dev = net_device;
+
+	/* Send the rndis initialization message */
+	ret = rndis_filter_init_device(rndis_device);
+	if (ret != 0) {
+		rndis_filter_device_remove(dev);
+		return ret;
+	}
+
+	/* Get the MTU from the host */
+	size = sizeof(u32);
+	ret = rndis_filter_query_device(rndis_device,
+					RNDIS_OID_GEN_MAXIMUM_FRAME_SIZE,
+					&mtu, &size);
+	if (ret == 0 && size == sizeof(u32))
+		net_device->ndev->mtu = mtu;
+
+	/* Get the mac address */
+	ret = rndis_filter_query_device_mac(rndis_device);
+	if (ret != 0) {
+		rndis_filter_device_remove(dev);
+		return ret;
+	}
+
+	memcpy(device_info->mac_adr, rndis_device->hw_mac_adr, ETH_ALEN);
+
+	/* Turn on the offloads; the host supports all of the relevant
+	 * offloads.
+	 */
+	memset(&offloads, 0, sizeof(struct ndis_offload_params));
+	/* A value of zero means "no change"; now turn on what we
+	 * want.
+	 */
+	offloads.ip_v4_csum = NDIS_OFFLOAD_PARAMETERS_TX_RX_ENABLED;
+	offloads.tcp_ip_v4_csum = NDIS_OFFLOAD_PARAMETERS_TX_RX_ENABLED;
+	offloads.udp_ip_v4_csum = NDIS_OFFLOAD_PARAMETERS_TX_RX_ENABLED;
+	offloads.tcp_ip_v6_csum = NDIS_OFFLOAD_PARAMETERS_TX_RX_ENABLED;
+	offloads.udp_ip_v6_csum = NDIS_OFFLOAD_PARAMETERS_TX_RX_ENABLED;
+	offloads.lso_v2_ipv4 = NDIS_OFFLOAD_PARAMETERS_LSOV2_ENABLED;
+
+
+	ret = rndis_filter_set_offload_params(dev, &offloads);
+	if (ret)
+		goto err_dev_remv;
+
+	rndis_filter_query_device_link_status(rndis_device);
+
+	device_info->link_state = rndis_device->link_state;
+
+	dev_info(&dev->device, "Device MAC %pM link state %s\n",
+		 rndis_device->hw_mac_adr,
+		 device_info->link_state ? "down" : "up");
+
+	if (net_device->nvsp_version < NVSP_PROTOCOL_VERSION_5)
+		return 0;
+
+	/* vRSS setup */
+	memset(&rsscap, 0, rsscap_size);
+	ret = rndis_filter_query_device(rndis_device,
+					OID_GEN_RECEIVE_SCALE_CAPABILITIES,
+					&rsscap, &rsscap_size);
+	if (ret || rsscap.num_recv_que < 2)
+		goto out;
+
+	net_device->max_chn = rsscap.num_recv_que;
+	net_device->num_chn = (num_online_cpus() < rsscap.num_recv_que) ?
+			       num_online_cpus() : rsscap.num_recv_que;
+	if (net_device->num_chn == 1)
+		goto out;
+
+	net_device->sub_cb_buf = vzalloc((net_device->num_chn - 1) *
+					 NETVSC_PACKET_SIZE);
+	if (!net_device->sub_cb_buf) {
+		net_device->num_chn = 1;
+		dev_info(&dev->device, "No memory for subchannels.\n");
+		goto out;
+	}
+
+	vmbus_set_sc_create_callback(dev->channel, netvsc_sc_open);
+
+	init_packet = &net_device->channel_init_pkt;
+	memset(init_packet, 0, sizeof(struct nvsp_message));
+	init_packet->hdr.msg_type = NVSP_MSG5_TYPE_SUBCHANNEL;
+	init_packet->msg.v5_msg.subchn_req.op = NVSP_SUBCHANNEL_ALLOCATE;
+	init_packet->msg.v5_msg.subchn_req.num_subchannels =
+						net_device->num_chn - 1;
+	ret = vmbus_sendpacket(dev->channel, init_packet,
+			       sizeof(struct nvsp_message),
+			       (unsigned long)init_packet,
+			       VM_PKT_DATA_INBAND,
+			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+	if (ret)
+		goto out;
+	t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
+	if (t == 0) {
+		ret = -ETIMEDOUT;
+		goto out;
+	}
+	if (init_packet->msg.v5_msg.subchn_comp.status !=
+	    NVSP_STAT_SUCCESS) {
+		ret = -ENODEV;
+		goto out;
+	}
+	net_device->num_chn = 1 +
+		init_packet->msg.v5_msg.subchn_comp.num_subchannels;
+
+	ret = rndis_filter_set_rss_param(rndis_device, net_device->num_chn);
+
+out:
+	if (ret) {
+		net_device->max_chn = 1;
+		net_device->num_chn = 1;
+	}
+	return 0; /* return 0 because primary channel can be used alone */
+
+err_dev_remv:
+	rndis_filter_device_remove(dev);
+	return ret;
+}
+
+void rndis_filter_device_remove(struct hv_device *dev)
+{
+	struct netvsc_device *net_dev = hv_get_drvdata(dev);
+	struct rndis_device *rndis_dev = net_dev->extension;
+
+	/* Halt and release the rndis device */
+	rndis_filter_halt_device(rndis_dev);
+
+	kfree(rndis_dev);
+	net_dev->extension = NULL;
+
+	netvsc_device_remove(dev);
+}
+
+
+int rndis_filter_open(struct hv_device *dev)
+{
+	struct netvsc_device *net_device = hv_get_drvdata(dev);
+
+	if (!net_device)
+		return -EINVAL;
+
+	return rndis_filter_open_device(net_device->extension);
+}
+
+int rndis_filter_close(struct hv_device *dev)
+{
+	struct netvsc_device *nvdev = hv_get_drvdata(dev);
+
+	if (!nvdev)
+		return -EINVAL;
+
+	return rndis_filter_close_device(nvdev->extension);
+}