ubuntu-linux-kernel/include/linux/avf/virtchnl.h

/*******************************************************************************
 *
 * Intel Ethernet Controller XL710 Family Linux Virtual Function Driver
 * Copyright(c) 2013 - 2014 Intel 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/>.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * Contact Information:
 * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 ******************************************************************************/

#ifndef _VIRTCHNL_H_
#define _VIRTCHNL_H_

/* Description:
 * This header file describes the VF-PF communication protocol used
 * by the drivers for all devices starting from our 40G product line
 *
 * Admin queue buffer usage:
 * desc->opcode is always aqc_opc_send_msg_to_pf
 * flags, retval, datalen, and data addr are all used normally.
 * The Firmware copies the cookie fields when sending messages between the
 * PF and VF, but uses all other fields internally. Due to this limitation,
 * we must send all messages as "indirect", i.e. using an external buffer.
 *
 * All the VSI indexes are relative to the VF. Each VF can have maximum of
 * three VSIs. All the queue indexes are relative to the VSI.  Each VF can
 * have a maximum of sixteen queues for all of its VSIs.
 *
 * The PF is required to return a status code in v_retval for all messages
 * except RESET_VF, which does not require any response. The return value
 * is of status_code type, defined in the shared type.h.
 *
 * In general, VF driver initialization should roughly follow the order of
 * these opcodes. The VF driver must first validate the API version of the
 * PF driver, then request a reset, then get resources, then configure
 * queues and interrupts. After these operations are complete, the VF
 * driver may start its queues, optionally add MAC and VLAN filters, and
 * process traffic.
 */

/* START GENERIC DEFINES
 * Need to ensure the following enums and defines hold the same meaning and
 * value in current and future projects
 */

/* Error Codes */
enum virtchnl_status_code {
	VIRTCHNL_STATUS_SUCCESS				= 0,
	VIRTCHNL_ERR_PARAM				= -5,
	VIRTCHNL_STATUS_ERR_OPCODE_MISMATCH		= -38,
	VIRTCHNL_STATUS_ERR_CQP_COMPL_ERROR		= -39,
	VIRTCHNL_STATUS_ERR_INVALID_VF_ID		= -40,
	VIRTCHNL_STATUS_NOT_SUPPORTED			= -64,
};

#define VIRTCHNL_LINK_SPEED_100MB_SHIFT		0x1
#define VIRTCHNL_LINK_SPEED_1000MB_SHIFT	0x2
#define VIRTCHNL_LINK_SPEED_10GB_SHIFT		0x3
#define VIRTCHNL_LINK_SPEED_40GB_SHIFT		0x4
#define VIRTCHNL_LINK_SPEED_20GB_SHIFT		0x5
#define VIRTCHNL_LINK_SPEED_25GB_SHIFT		0x6

enum virtchnl_link_speed {
	VIRTCHNL_LINK_SPEED_UNKNOWN	= 0,
	VIRTCHNL_LINK_SPEED_100MB	= BIT(VIRTCHNL_LINK_SPEED_100MB_SHIFT),
	VIRTCHNL_LINK_SPEED_1GB		= BIT(VIRTCHNL_LINK_SPEED_1000MB_SHIFT),
	VIRTCHNL_LINK_SPEED_10GB	= BIT(VIRTCHNL_LINK_SPEED_10GB_SHIFT),
	VIRTCHNL_LINK_SPEED_40GB	= BIT(VIRTCHNL_LINK_SPEED_40GB_SHIFT),
	VIRTCHNL_LINK_SPEED_20GB	= BIT(VIRTCHNL_LINK_SPEED_20GB_SHIFT),
	VIRTCHNL_LINK_SPEED_25GB	= BIT(VIRTCHNL_LINK_SPEED_25GB_SHIFT),
};

/* for hsplit_0 field of Rx HMC context */
/* deprecated with AVF 1.0 */
enum virtchnl_rx_hsplit {
	VIRTCHNL_RX_HSPLIT_NO_SPLIT      = 0,
	VIRTCHNL_RX_HSPLIT_SPLIT_L2      = 1,
	VIRTCHNL_RX_HSPLIT_SPLIT_IP      = 2,
	VIRTCHNL_RX_HSPLIT_SPLIT_TCP_UDP = 4,
	VIRTCHNL_RX_HSPLIT_SPLIT_SCTP    = 8,
};

/* END GENERIC DEFINES */

/* Opcodes for VF-PF communication. These are placed in the v_opcode field
 * of the virtchnl_msg structure.
 */
enum virtchnl_ops {
/* The PF sends status change events to VFs using
 * the VIRTCHNL_OP_EVENT opcode.
 * VFs send requests to the PF using the other ops.
 * Use of "advanced opcode" features must be negotiated as part of capabilities
 * exchange and are not considered part of base mode feature set.
 */
	VIRTCHNL_OP_UNKNOWN = 0,
	VIRTCHNL_OP_VERSION = 1, /* must ALWAYS be 1 */
	VIRTCHNL_OP_RESET_VF = 2,
	VIRTCHNL_OP_GET_VF_RESOURCES = 3,
	VIRTCHNL_OP_CONFIG_TX_QUEUE = 4,
	VIRTCHNL_OP_CONFIG_RX_QUEUE = 5,
	VIRTCHNL_OP_CONFIG_VSI_QUEUES = 6,
	VIRTCHNL_OP_CONFIG_IRQ_MAP = 7,
	VIRTCHNL_OP_ENABLE_QUEUES = 8,
	VIRTCHNL_OP_DISABLE_QUEUES = 9,
	VIRTCHNL_OP_ADD_ETH_ADDR = 10,
	VIRTCHNL_OP_DEL_ETH_ADDR = 11,
	VIRTCHNL_OP_ADD_VLAN = 12,
	VIRTCHNL_OP_DEL_VLAN = 13,
	VIRTCHNL_OP_CONFIG_PROMISCUOUS_MODE = 14,
	VIRTCHNL_OP_GET_STATS = 15,
	VIRTCHNL_OP_RSVD = 16,
	VIRTCHNL_OP_EVENT = 17, /* must ALWAYS be 17 */
	VIRTCHNL_OP_IWARP = 20, /* advanced opcode */
	VIRTCHNL_OP_CONFIG_IWARP_IRQ_MAP = 21, /* advanced opcode */
	VIRTCHNL_OP_RELEASE_IWARP_IRQ_MAP = 22, /* advanced opcode */
	VIRTCHNL_OP_CONFIG_RSS_KEY = 23,
	VIRTCHNL_OP_CONFIG_RSS_LUT = 24,
	VIRTCHNL_OP_GET_RSS_HENA_CAPS = 25,
	VIRTCHNL_OP_SET_RSS_HENA = 26,
	VIRTCHNL_OP_ENABLE_VLAN_STRIPPING = 27,
	VIRTCHNL_OP_DISABLE_VLAN_STRIPPING = 28,
	VIRTCHNL_OP_REQUEST_QUEUES = 29,
};

/* This macro is used to generate a compilation error if a structure
 * is not exactly the correct length. It gives a divide by zero error if the
 * structure is not of the correct size, otherwise it creates an enum that is
 * never used.
 */
#define VIRTCHNL_CHECK_STRUCT_LEN(n, X) enum virtchnl_static_assert_enum_##X \
	{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }

/* Virtual channel message descriptor. This overlays the admin queue
 * descriptor. All other data is passed in external buffers.
 */

struct virtchnl_msg {
	u8 pad[8];			 /* AQ flags/opcode/len/retval fields */
	enum virtchnl_ops v_opcode; /* avoid confusion with desc->opcode */
	enum virtchnl_status_code v_retval;  /* ditto for desc->retval */
	u32 vfid;			 /* used by PF when sending to VF */
};

VIRTCHNL_CHECK_STRUCT_LEN(20, virtchnl_msg);

/* Message descriptions and data structures.*/

/* VIRTCHNL_OP_VERSION
 * VF posts its version number to the PF. PF responds with its version number
 * in the same format, along with a return code.
 * Reply from PF has its major/minor versions also in param0 and param1.
 * If there is a major version mismatch, then the VF cannot operate.
 * If there is a minor version mismatch, then the VF can operate but should
 * add a warning to the system log.
 *
 * This enum element MUST always be specified as == 1, regardless of other
 * changes in the API. The PF must always respond to this message without
 * error regardless of version mismatch.
 */
#define VIRTCHNL_VERSION_MAJOR		1
#define VIRTCHNL_VERSION_MINOR		1
#define VIRTCHNL_VERSION_MINOR_NO_VF_CAPS	0

struct virtchnl_version_info {
	u32 major;
	u32 minor;
};

VIRTCHNL_CHECK_STRUCT_LEN(8, virtchnl_version_info);

#define VF_IS_V10(_v) (((_v)->major == 1) && ((_v)->minor == 0))
#define VF_IS_V11(_ver) (((_ver)->major == 1) && ((_ver)->minor == 1))

/* VIRTCHNL_OP_RESET_VF
 * VF sends this request to PF with no parameters
 * PF does NOT respond! VF driver must delay then poll VFGEN_RSTAT register
 * until reset completion is indicated. The admin queue must be reinitialized
 * after this operation.
 *
 * When reset is complete, PF must ensure that all queues in all VSIs associated
 * with the VF are stopped, all queue configurations in the HMC are set to 0,
 * and all MAC and VLAN filters (except the default MAC address) on all VSIs
 * are cleared.
 */

/* VSI types that use VIRTCHNL interface for VF-PF communication. VSI_SRIOV
 * vsi_type should always be 6 for backward compatibility. Add other fields
 * as needed.
 */
enum virtchnl_vsi_type {
	VIRTCHNL_VSI_TYPE_INVALID = 0,
	VIRTCHNL_VSI_SRIOV = 6,
};

/* VIRTCHNL_OP_GET_VF_RESOURCES
 * Version 1.0 VF sends this request to PF with no parameters
 * Version 1.1 VF sends this request to PF with u32 bitmap of its capabilities
 * PF responds with an indirect message containing
 * virtchnl_vf_resource and one or more
 * virtchnl_vsi_resource structures.
 */

struct virtchnl_vsi_resource {
	u16 vsi_id;
	u16 num_queue_pairs;
	enum virtchnl_vsi_type vsi_type;
	u16 qset_handle;
	u8 default_mac_addr[ETH_ALEN];
};

VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_vsi_resource);

/* VF capability flags
 * VIRTCHNL_VF_OFFLOAD_L2 flag is inclusive of base mode L2 offloads including
 * TX/RX Checksum offloading and TSO for non-tunnelled packets.
 */
#define VIRTCHNL_VF_OFFLOAD_L2			0x00000001
#define VIRTCHNL_VF_OFFLOAD_IWARP		0x00000002
#define VIRTCHNL_VF_OFFLOAD_RSVD		0x00000004
#define VIRTCHNL_VF_OFFLOAD_RSS_AQ		0x00000008
#define VIRTCHNL_VF_OFFLOAD_RSS_REG		0x00000010
#define VIRTCHNL_VF_OFFLOAD_WB_ON_ITR		0x00000020
#define VIRTCHNL_VF_OFFLOAD_REQ_QUEUES		0x00000040
#define VIRTCHNL_VF_OFFLOAD_VLAN		0x00010000
#define VIRTCHNL_VF_OFFLOAD_RX_POLLING		0x00020000
#define VIRTCHNL_VF_OFFLOAD_RSS_PCTYPE_V2	0x00040000
#define VIRTCHNL_VF_OFFLOAD_RSS_PF		0X00080000
#define VIRTCHNL_VF_OFFLOAD_ENCAP		0X00100000
#define VIRTCHNL_VF_OFFLOAD_ENCAP_CSUM		0X00200000
#define VIRTCHNL_VF_OFFLOAD_RX_ENCAP_CSUM	0X00400000

#define VF_BASE_MODE_OFFLOADS (VIRTCHNL_VF_OFFLOAD_L2 | \
			       VIRTCHNL_VF_OFFLOAD_VLAN | \
			       VIRTCHNL_VF_OFFLOAD_RSS_PF)

struct virtchnl_vf_resource {
	u16 num_vsis;
	u16 num_queue_pairs;
	u16 max_vectors;
	u16 max_mtu;

	u32 vf_cap_flags;
	u32 rss_key_size;
	u32 rss_lut_size;

	struct virtchnl_vsi_resource vsi_res[1];
};

VIRTCHNL_CHECK_STRUCT_LEN(36, virtchnl_vf_resource);

/* VIRTCHNL_OP_CONFIG_TX_QUEUE
 * VF sends this message to set up parameters for one TX queue.
 * External data buffer contains one instance of virtchnl_txq_info.
 * PF configures requested queue and returns a status code.
 */

/* Tx queue config info */
struct virtchnl_txq_info {
	u16 vsi_id;
	u16 queue_id;
	u16 ring_len;		/* number of descriptors, multiple of 8 */
	u16 headwb_enabled; /* deprecated with AVF 1.0 */
	u64 dma_ring_addr;
	u64 dma_headwb_addr; /* deprecated with AVF 1.0 */
};

VIRTCHNL_CHECK_STRUCT_LEN(24, virtchnl_txq_info);

/* VIRTCHNL_OP_CONFIG_RX_QUEUE
 * VF sends this message to set up parameters for one RX queue.
 * External data buffer contains one instance of virtchnl_rxq_info.
 * PF configures requested queue and returns a status code.
 */

/* Rx queue config info */
struct virtchnl_rxq_info {
	u16 vsi_id;
	u16 queue_id;
	u32 ring_len;		/* number of descriptors, multiple of 32 */
	u16 hdr_size;
	u16 splithdr_enabled; /* deprecated with AVF 1.0 */
	u32 databuffer_size;
	u32 max_pkt_size;
	u32 pad1;
	u64 dma_ring_addr;
	enum virtchnl_rx_hsplit rx_split_pos; /* deprecated with AVF 1.0 */
	u32 pad2;
};

VIRTCHNL_CHECK_STRUCT_LEN(40, virtchnl_rxq_info);

/* VIRTCHNL_OP_CONFIG_VSI_QUEUES
 * VF sends this message to set parameters for all active TX and RX queues
 * associated with the specified VSI.
 * PF configures queues and returns status.
 * If the number of queues specified is greater than the number of queues
 * associated with the VSI, an error is returned and no queues are configured.
 */
struct virtchnl_queue_pair_info {
	/* NOTE: vsi_id and queue_id should be identical for both queues. */
	struct virtchnl_txq_info txq;
	struct virtchnl_rxq_info rxq;
};

VIRTCHNL_CHECK_STRUCT_LEN(64, virtchnl_queue_pair_info);

struct virtchnl_vsi_queue_config_info {
	u16 vsi_id;
	u16 num_queue_pairs;
	u32 pad;
	struct virtchnl_queue_pair_info qpair[1];
};

/* VIRTCHNL_OP_REQUEST_QUEUES
 * VF sends this message to request the PF to allocate additional queues to
 * this VF.  Each VF gets a guaranteed number of queues on init but asking for
 * additional queues must be negotiated.  This is a best effort request as it
 * is possible the PF does not have enough queues left to support the request.
 * If the PF cannot support the number requested it will respond with the
 * maximum number it is able to support.  If the request is successful, PF will
 * then reset the VF to institute required changes.
 */

/* VF resource request */
struct virtchnl_vf_res_request {
	u16 num_queue_pairs;
};

VIRTCHNL_CHECK_STRUCT_LEN(72, virtchnl_vsi_queue_config_info);

/* VIRTCHNL_OP_CONFIG_IRQ_MAP
 * VF uses this message to map vectors to queues.
 * The rxq_map and txq_map fields are bitmaps used to indicate which queues
 * are to be associated with the specified vector.
 * The "other" causes are always mapped to vector 0.
 * PF configures interrupt mapping and returns status.
 */
struct virtchnl_vector_map {
	u16 vsi_id;
	u16 vector_id;
	u16 rxq_map;
	u16 txq_map;
	u16 rxitr_idx;
	u16 txitr_idx;
};

VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_vector_map);

struct virtchnl_irq_map_info {
	u16 num_vectors;
	struct virtchnl_vector_map vecmap[1];
};

VIRTCHNL_CHECK_STRUCT_LEN(14, virtchnl_irq_map_info);

/* VIRTCHNL_OP_ENABLE_QUEUES
 * VIRTCHNL_OP_DISABLE_QUEUES
 * VF sends these message to enable or disable TX/RX queue pairs.
 * The queues fields are bitmaps indicating which queues to act upon.
 * (Currently, we only support 16 queues per VF, but we make the field
 * u32 to allow for expansion.)
 * PF performs requested action and returns status.
 */
struct virtchnl_queue_select {
	u16 vsi_id;
	u16 pad;
	u32 rx_queues;
	u32 tx_queues;
};

VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_queue_select);

/* VIRTCHNL_OP_ADD_ETH_ADDR
 * VF sends this message in order to add one or more unicast or multicast
 * address filters for the specified VSI.
 * PF adds the filters and returns status.
 */

/* VIRTCHNL_OP_DEL_ETH_ADDR
 * VF sends this message in order to remove one or more unicast or multicast
 * filters for the specified VSI.
 * PF removes the filters and returns status.
 */

struct virtchnl_ether_addr {
	u8 addr[ETH_ALEN];
	u8 pad[2];
};

VIRTCHNL_CHECK_STRUCT_LEN(8, virtchnl_ether_addr);

struct virtchnl_ether_addr_list {
	u16 vsi_id;
	u16 num_elements;
	struct virtchnl_ether_addr list[1];
};

VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_ether_addr_list);

/* VIRTCHNL_OP_ADD_VLAN
 * VF sends this message to add one or more VLAN tag filters for receives.
 * PF adds the filters and returns status.
 * If a port VLAN is configured by the PF, this operation will return an
 * error to the VF.
 */

/* VIRTCHNL_OP_DEL_VLAN
 * VF sends this message to remove one or more VLAN tag filters for receives.
 * PF removes the filters and returns status.
 * If a port VLAN is configured by the PF, this operation will return an
 * error to the VF.
 */

struct virtchnl_vlan_filter_list {
	u16 vsi_id;
	u16 num_elements;
	u16 vlan_id[1];
};

VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_vlan_filter_list);

/* VIRTCHNL_OP_CONFIG_PROMISCUOUS_MODE
 * VF sends VSI id and flags.
 * PF returns status code in retval.
 * Note: we assume that broadcast accept mode is always enabled.
 */
struct virtchnl_promisc_info {
	u16 vsi_id;
	u16 flags;
};

VIRTCHNL_CHECK_STRUCT_LEN(4, virtchnl_promisc_info);

#define FLAG_VF_UNICAST_PROMISC	0x00000001
#define FLAG_VF_MULTICAST_PROMISC	0x00000002

/* VIRTCHNL_OP_GET_STATS
 * VF sends this message to request stats for the selected VSI. VF uses
 * the virtchnl_queue_select struct to specify the VSI. The queue_id
 * field is ignored by the PF.
 *
 * PF replies with struct eth_stats in an external buffer.
 */

/* VIRTCHNL_OP_CONFIG_RSS_KEY
 * VIRTCHNL_OP_CONFIG_RSS_LUT
 * VF sends these messages to configure RSS. Only supported if both PF
 * and VF drivers set the VIRTCHNL_VF_OFFLOAD_RSS_PF bit during
 * configuration negotiation. If this is the case, then the RSS fields in
 * the VF resource struct are valid.
 * Both the key and LUT are initialized to 0 by the PF, meaning that
 * RSS is effectively disabled until set up by the VF.
 */
struct virtchnl_rss_key {
	u16 vsi_id;
	u16 key_len;
	u8 key[1];         /* RSS hash key, packed bytes */
};

VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_key);

struct virtchnl_rss_lut {
	u16 vsi_id;
	u16 lut_entries;
	u8 lut[1];        /* RSS lookup table*/
};

VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_lut);

/* VIRTCHNL_OP_GET_RSS_HENA_CAPS
 * VIRTCHNL_OP_SET_RSS_HENA
 * VF sends these messages to get and set the hash filter enable bits for RSS.
 * By default, the PF sets these to all possible traffic types that the
 * hardware supports. The VF can query this value if it wants to change the
 * traffic types that are hashed by the hardware.
 */
struct virtchnl_rss_hena {
	u64 hena;
};

VIRTCHNL_CHECK_STRUCT_LEN(8, virtchnl_rss_hena);

/* VIRTCHNL_OP_EVENT
 * PF sends this message to inform the VF driver of events that may affect it.
 * No direct response is expected from the VF, though it may generate other
 * messages in response to this one.
 */
enum virtchnl_event_codes {
	VIRTCHNL_EVENT_UNKNOWN = 0,
	VIRTCHNL_EVENT_LINK_CHANGE,
	VIRTCHNL_EVENT_RESET_IMPENDING,
	VIRTCHNL_EVENT_PF_DRIVER_CLOSE,
};

#define PF_EVENT_SEVERITY_INFO		0
#define PF_EVENT_SEVERITY_CERTAIN_DOOM	255

struct virtchnl_pf_event {
	enum virtchnl_event_codes event;
	union {
		struct {
			enum virtchnl_link_speed link_speed;
			bool link_status;
		} link_event;
	} event_data;

	int severity;
};

VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_pf_event);

/* VIRTCHNL_OP_CONFIG_IWARP_IRQ_MAP
 * VF uses this message to request PF to map IWARP vectors to IWARP queues.
 * The request for this originates from the VF IWARP driver through
 * a client interface between VF LAN and VF IWARP driver.
 * A vector could have an AEQ and CEQ attached to it although
 * there is a single AEQ per VF IWARP instance in which case
 * most vectors will have an INVALID_IDX for aeq and valid idx for ceq.
 * There will never be a case where there will be multiple CEQs attached
 * to a single vector.
 * PF configures interrupt mapping and returns status.
 */

struct virtchnl_iwarp_qv_info {
	u32 v_idx; /* msix_vector */
	u16 ceq_idx;
	u16 aeq_idx;
	u8 itr_idx;
};

VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);

struct virtchnl_iwarp_qvlist_info {
	u32 num_vectors;
	struct virtchnl_iwarp_qv_info qv_info[1];
};

VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_iwarp_qvlist_info);

/* VF reset states - these are written into the RSTAT register:
 * VFGEN_RSTAT on the VF
 * When the PF initiates a reset, it writes 0
 * When the reset is complete, it writes 1
 * When the PF detects that the VF has recovered, it writes 2
 * VF checks this register periodically to determine if a reset has occurred,
 * then polls it to know when the reset is complete.
 * If either the PF or VF reads the register while the hardware
 * is in a reset state, it will return DEADBEEF, which, when masked
 * will result in 3.
 */
enum virtchnl_vfr_states {
	VIRTCHNL_VFR_INPROGRESS = 0,
	VIRTCHNL_VFR_COMPLETED,
	VIRTCHNL_VFR_VFACTIVE,
};

/**
 * virtchnl_vc_validate_vf_msg
 * @ver: Virtchnl version info
 * @v_opcode: Opcode for the message
 * @msg: pointer to the msg buffer
 * @msglen: msg length
 *
 * validate msg format against struct for each opcode
 */
static inline int
virtchnl_vc_validate_vf_msg(struct virtchnl_version_info *ver, u32 v_opcode,
			    u8 *msg, u16 msglen)
{
	bool err_msg_format = false;
	int valid_len = 0;

	/* Validate message length. */
	switch (v_opcode) {
	case VIRTCHNL_OP_VERSION:
		valid_len = sizeof(struct virtchnl_version_info);
		break;
	case VIRTCHNL_OP_RESET_VF:
		break;
	case VIRTCHNL_OP_GET_VF_RESOURCES:
		if (VF_IS_V11(ver))
			valid_len = sizeof(u32);
		break;
	case VIRTCHNL_OP_CONFIG_TX_QUEUE:
		valid_len = sizeof(struct virtchnl_txq_info);
		break;
	case VIRTCHNL_OP_CONFIG_RX_QUEUE:
		valid_len = sizeof(struct virtchnl_rxq_info);
		break;
	case VIRTCHNL_OP_CONFIG_VSI_QUEUES:
		valid_len = sizeof(struct virtchnl_vsi_queue_config_info);
		if (msglen >= valid_len) {
			struct virtchnl_vsi_queue_config_info *vqc =
			    (struct virtchnl_vsi_queue_config_info *)msg;
			valid_len += (vqc->num_queue_pairs *
				      sizeof(struct
					     virtchnl_queue_pair_info));
			if (vqc->num_queue_pairs == 0)
				err_msg_format = true;
		}
		break;
	case VIRTCHNL_OP_CONFIG_IRQ_MAP:
		valid_len = sizeof(struct virtchnl_irq_map_info);
		if (msglen >= valid_len) {
			struct virtchnl_irq_map_info *vimi =
			    (struct virtchnl_irq_map_info *)msg;
			valid_len += (vimi->num_vectors *
				      sizeof(struct virtchnl_vector_map));
			if (vimi->num_vectors == 0)
				err_msg_format = true;
		}
		break;
	case VIRTCHNL_OP_ENABLE_QUEUES:
	case VIRTCHNL_OP_DISABLE_QUEUES:
		valid_len = sizeof(struct virtchnl_queue_select);
		break;
	case VIRTCHNL_OP_ADD_ETH_ADDR:
	case VIRTCHNL_OP_DEL_ETH_ADDR:
		valid_len = sizeof(struct virtchnl_ether_addr_list);
		if (msglen >= valid_len) {
			struct virtchnl_ether_addr_list *veal =
			    (struct virtchnl_ether_addr_list *)msg;
			valid_len += veal->num_elements *
			    sizeof(struct virtchnl_ether_addr);
			if (veal->num_elements == 0)
				err_msg_format = true;
		}
		break;
	case VIRTCHNL_OP_ADD_VLAN:
	case VIRTCHNL_OP_DEL_VLAN:
		valid_len = sizeof(struct virtchnl_vlan_filter_list);
		if (msglen >= valid_len) {
			struct virtchnl_vlan_filter_list *vfl =
			    (struct virtchnl_vlan_filter_list *)msg;
			valid_len += vfl->num_elements * sizeof(u16);
			if (vfl->num_elements == 0)
				err_msg_format = true;
		}
		break;
	case VIRTCHNL_OP_CONFIG_PROMISCUOUS_MODE:
		valid_len = sizeof(struct virtchnl_promisc_info);
		break;
	case VIRTCHNL_OP_GET_STATS:
		valid_len = sizeof(struct virtchnl_queue_select);
		break;
	case VIRTCHNL_OP_IWARP:
		/* These messages are opaque to us and will be validated in
		 * the RDMA client code. We just need to check for nonzero
		 * length. The firmware will enforce max length restrictions.
		 */
		if (msglen)
			valid_len = msglen;
		else
			err_msg_format = true;
		break;
	case VIRTCHNL_OP_RELEASE_IWARP_IRQ_MAP:
		break;
	case VIRTCHNL_OP_CONFIG_IWARP_IRQ_MAP:
		valid_len = sizeof(struct virtchnl_iwarp_qvlist_info);
		if (msglen >= valid_len) {
			struct virtchnl_iwarp_qvlist_info *qv =
				(struct virtchnl_iwarp_qvlist_info *)msg;
			if (qv->num_vectors == 0) {
				err_msg_format = true;
				break;
			}
			valid_len += ((qv->num_vectors - 1) *
				sizeof(struct virtchnl_iwarp_qv_info));
		}
		break;
	case VIRTCHNL_OP_CONFIG_RSS_KEY:
		valid_len = sizeof(struct virtchnl_rss_key);
		if (msglen >= valid_len) {
			struct virtchnl_rss_key *vrk =
				(struct virtchnl_rss_key *)msg;
			valid_len += vrk->key_len - 1;
		}
		break;
	case VIRTCHNL_OP_CONFIG_RSS_LUT:
		valid_len = sizeof(struct virtchnl_rss_lut);
		if (msglen >= valid_len) {
			struct virtchnl_rss_lut *vrl =
				(struct virtchnl_rss_lut *)msg;
			valid_len += vrl->lut_entries - 1;
		}
		break;
	case VIRTCHNL_OP_GET_RSS_HENA_CAPS:
		break;
	case VIRTCHNL_OP_SET_RSS_HENA:
		valid_len = sizeof(struct virtchnl_rss_hena);
		break;
	case VIRTCHNL_OP_ENABLE_VLAN_STRIPPING:
	case VIRTCHNL_OP_DISABLE_VLAN_STRIPPING:
		break;
	case VIRTCHNL_OP_REQUEST_QUEUES:
		valid_len = sizeof(struct virtchnl_vf_res_request);
		break;
	/* These are always errors coming from the VF. */
	case VIRTCHNL_OP_EVENT:
	case VIRTCHNL_OP_UNKNOWN:
	default:
		return VIRTCHNL_ERR_PARAM;
	}
	/* few more checks */
	if ((valid_len != msglen) || (err_msg_format))
		return VIRTCHNL_STATUS_ERR_OPCODE_MISMATCH;

	return 0;
}
#endif /* _VIRTCHNL_H_ */