Commit 47443222 authored Jun 16, 2016 by Shrikrishna Khare Committed by David S. Miller Jun 16, 2016

vmxnet3: introduce command to register memory region



In vmxnet3 version 3, the emulation added support for the vmxnet3 driver
to communicate information about the memory regions the driver will use
for rx/tx buffers. The driver can also indicate which rx/tx queue the
memory region is applicable for. If this information is communicated
to the emulation, the emulation will always keep these memory regions
mapped, thereby avoiding the mapping/unmapping overhead for every packet.

Currently, Linux vmxnet3 driver does not leverage this capability. The
feasibility of using this approach for the Linux vmxnet3 driver will be
investigated independently and if possible, will be part of a different
patch. This patch only exposes the emulation capability to the driver
(vmxnet3_defs.h is identical between the driver and the emulation).

Signed-off-by: Guolin Yang <gyang@vmware.com>
Signed-off-by: Shrikrishna Khare <skhare@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 4edef40e

drivers/net/vmxnet3/vmxnet3_defs.h

+17 −0

Original line number	Diff line number	Diff line
		@@ -81,6 +81,7 @@ enum {
		VMXNET3_CMD_RESERVED2,
		VMXNET3_CMD_RESERVED3,
		VMXNET3_CMD_SET_COALESCE,
		VMXNET3_CMD_REGISTER_MEMREGS,

		VMXNET3_CMD_FIRST_GET = 0xF00D0000,
		VMXNET3_CMD_GET_QUEUE_STATUS = VMXNET3_CMD_FIRST_GET,
		@@ -668,6 +669,22 @@ struct Vmxnet3_CoalesceScheme {
		} coalPara;
		};

		struct Vmxnet3_MemoryRegion {
		__le64 startPA;
		__le32 length;
		__le16 txQueueBits;
		__le16 rxQueueBits;
		};

		#define MAX_MEMORY_REGION_PER_QUEUE 16
		#define MAX_MEMORY_REGION_PER_DEVICE 256

		struct Vmxnet3_MemRegs {
		__le16 numRegs;
		__le16 pad[3];
		struct Vmxnet3_MemoryRegion memRegs[1];
		};

		/* If the command data <= 16 bytes, use the shared memory directly.
		* otherwise, use variable length configuration descriptor.
		*/