Peripheral device that DMAS the same data to different locations in a computer

• US 20080263171A1
• Filed: 04/19/2007
• Published: 10/23/2008
• Est. Priority Date: 04/19/2007
• Status: Abandoned Application

• Current Assignee: Alacritech, Inc.
• Original Assignee: Alacritech, Inc.
• Inventors: Philbrick, Clive M., Craft, Peter K.
• Application Number:
  US11/788,719
• Publication Number:
  US 20080263171A1
• Time in Patent Office: Days
• US Class Current: 709/212
• CPC Class Codes: G06F 13/28 using burst mode transfer, e.g. direct memory access DMA, cycle steal G06F13/32 takes precedence
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]

Abstract

A method is disclosed comprising: receiving,.by a network interface, data and a corresponding header; storing, by the network interface, the data in a first memory buffer of a computer that is coupled to the network interface; and storing, by the network interface, the data in a second memory buffer of the computer. For example, the network interface can first store the data in a part of the computer memory that is accessible by a device driver for the network interface. If the application provides to the driver a pointer to a location in memory for storing the data, the driver can pass this pointer to the network interface, which can write the data directly to that location without copying by the CPU. If, however, the application does not provide a pointer, the data controlled by the driver can be copied by the CPU into the application'"'"'s memory space.

Claims

1. A method comprising:

receiving, by a network interface, data and a corresponding header;

storing, by the network interface, the data in a first memory buffer of a computer that is operably coupled to the network interface; and

storing, by the network interface, the data in a second memory buffer of the computer.

2. The method of claim 1, wherein the data is part of a message containing related data, further comprising:

copying, by the computer, the related data from the first memory buffer to the second memory buffer.

3. The method of claim 2, further comprising:

providing, to the network interface, a byte count corresponding to the related data that has been copied to the second memory buffer; and

discarding the related data from the network interface in response to receiving the byte count.

4. The method of claim 2, further comprising:

providing, to the network interface, a sequence number corresponding to the related data that has been copied to the second memory buffer; and

discarding the related data from the network interface in response to receiving the sequence number.

5. The method of claim 1, further comprising:

processing the header by the computer, after the storing of the data in the first memory buffer and before the storing of the data in the second memory buffer.

6. The method of claim 1, further comprising:

maintaining, at the network interface, a copy of the data after the storing of the data in the first memory buffer; and

accessing the copy for the storing of the data in the second memory buffer.

7. The method of claim 1, wherein the network interface copies the data from the first memory buffer to the second memory buffer.

8. The method of claim 1, further comprising:

copying, by the network interface, the data in the first memory buffer, for the storing of the data in the second memory buffer.

9. The method of claim 1, wherein the data in the first memory buffer is controlled by a device driver running on the processor, and the data in the second memory buffer is controlled by an application running on the processor.

10. The method of claim 1, wherein the header includes Transmission Control Protocol (TCP) information.

11. The method of claim 1, wherein the network interface includes a direct memory access (DMA) engine that performs the storing.

12. The method of claim 1, further comprising:

discarding the data in the first memory buffer of the memory, in response to the storing, by the network interface, the data in a second memory buffer of the computer.

13. A method comprising:

receiving, by a network interface that is operably coupled to a computer having a processor and a memory, a message including a plurality of packets;

storing, by the network interface, first data from a first of the packets in a first location of the memory; and

storing, by the network interface, the first data in a second location of the memory.

14. The method of claim 13, further comprising:

copying, by the computer, second data from a second of the packets to the second location.

15. The method of claim 14, further comprising:

providing, to the network interface, a sequence number corresponding to the second data that has been copied to the second location; and

discarding the second data from the network interface in response to receiving the sequence number.

16. The method of claim 13, further comprising:

processing, by the processor, a header corresponding to the first data, including obtaining a pointer to the second location in the memory.

17. The method of claim 13, further comprising:

discarding the first data in the first location of the memory, in response to receiving a signal that the first data has been saved in the second location in memory.

18. The method of claim 13, further comprising:

maintaining, at the network interface, a copy of the first data after the storing of the first data in the first location.

19. The method of claim 13, further comprising:

storing, in a register, an indication of a control block corresponding to the message and a byte count corresponding to message data that has been consumed by an application running on the processor.

20. The method of claim 13, further comprising:

storing, in a register, an indication of a control block corresponding to the message and a sequence number corresponding to message data that has been consumed by an application running on the processor.

21. The method of claim 13, wherein data in the first location is controlled by a device driver running on the processor, and data in the second location is controlled by an application running on the processor.

22. The method of claim 13, wherein the header includes Transmission Control Protocol (TCP) information.

23. The method of claim 13, wherein the network interface includes a direct memory access (DMA) engine that performs the storing.

24. An apparatus comprising:

a computer having a processor and a memory; and

a peripheral device that is operably coupled to the computer, the peripheral device adapted to store a block of data in two different locations of the memory.

25. The apparatus of claim 24, wherein the peripheral device contains a direct memory access (DMA) unit that accesses the memory to store the block of data in the two different locations of the memory.

26. The apparatus of claim 24, further comprising a register adapted to store an indication of a control block corresponding to the message and a byte count corresponding to message data that has been consumed by an application.

27. The apparatus of claim 24, further comprising a register adapted to store an indication of a control block corresponding to the message and a sequence number corresponding to message data that has been consumed by an application.

28. The apparatus of claim 24, further comprising:

an application running on the computer and receiving a message; and

a register adapted to store an indication of a control block corresponding to the message and a byte count corresponding to message data that has been consumed by the application.

29. The apparatus of claim 24, further comprising:

an application running on the computer and receiving a message; and

a register adapted to store an indication of a control block corresponding to the message and a sequence number corresponding to message data that has been consumed by the application.

30. An apparatus comprising:

a computer having a processor and a memory that holds the same data in two different locations; and

a peripheral device that is operably coupled to the computer, the peripheral device adapted to access the memory and having a device memory that holds a copy of the data that is stored in two different locations.