System and method for a multi-packet data link layer data transmission

• US 7,512,128 B2
• Filed: 05/09/2003
• Issued: 03/31/2009
• Est. Priority Date: 06/12/2002
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: DiMambro, Francesco R., Masputra, Cahya Adi
• Primary Examiner(s): Rao; Seema S
• Assistant Examiner(s): Chan; Sai-Ming
• Application Number:
  US10/434,810
• Publication Number:
  US 20030231659A1
• Time in Patent Office: 2,153 Days
• Field of Search: 370/473, 370/393, 370/474, 709/250
• US Class Current: 370/393
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/901 using storage descriptor, e.g. read or write pointers
• CPC Class Codes: H04L 49/9042 Separate storage for different parts of the packet, e.g. header and payload
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A kernel data transfer method and system for transmitting multiple packets of data in a single block of data presented by application programs to the kernel'"'"'s network subsystem for processing in accordance with data transfer parameters set by the application program. The multi-packet transmit system includes logic that allows header information of the multiple packets of data to be generated in a single buffer and appended to a second buffer containing the data packets to be transmitted through the network stack. The multi-data transmit system allows a device driver to amortize the input/output memory management related overhead across a number of packets. With some assistance from the network stack, the device driver needs to only perform the necessary IOMMU operations on two contiguous memory blocks representing the header information and the data payload of multiple packets during each transmit call.

Claims

1. A computer network system, comprising:

a processor;

a plurality of network devices;

a device driver;

a transport module to create a single consolidated transport header for multiple data packets;

an operating system kernel comprising a multi-packet transmission system to transmit the multiple data packets in a single transmission cycle to a network device coupled to the computer system in a single system call to a data link layer in said operating system kernel, a data size of each of the multiple data packets is dynamically set according to data transfer parameters of the underlying kernel application program to avoid a breakdown of application data into maximum segment size data packets determined by a TCP module prior to being transmitted through a network subsystem,

wherein, the multi-packet transmission system comprising a contiguous block of a plurality of header information with associated payload data information defines the single consolidated transport header in a single buffer and appended to a second buffer containing the data packets to be transmitted through a network stack.

2. The computer system of claim 1, wherein said multi-packet transmission system comprises an array of packet information logic modules for storing information required to access header and payload information in each packet.

3. The computer system of claim 2, wherein said multi-packet transmission system further comprises a packet stack header logic module.

4. The computer system of claim 3, wherein said multi-packet transmission system further comprises a packet offload logic module for defining device offload types for the multi-packet transmission system.

5. The computer network system of claim 4, wherein said multi-packet transmission system further comprises a layer 2 addressing logic module for transmitting said multiple packet data as layer 2 addressing packets.

6. The computer network system of claim 2, wherein said packet information logic modules comprise header length information for defining space to set aside in main memory from the beginning of a current packet header to the beginning of the current layers header to enable the multi-packet transmission system to traverse a protocol stack in said network system.

7. The computer network system of claim 6, wherein said packet information logic modules further comprise packet tail length information for defining space set aside said main memory, from the end of a current layer header to the end of the space set aside for the current packet header.

8. The computer network system of claim 7, wherein said packet information logic modules further comprise packet header offset information for defining header offset information relative to the base of the header buffer for calculating header input/output address posted to said network device for the current packet to be fetched by said network device and transmitted.

9. The computer network system of claim 8, wherein said packet information logic modules further comprise packet header length information for defining a total length of all headers for a particular packet.

10. The computer network system of claim 9, wherein said packet information logic modules further comprise offload offset information for defining a staffing offset for a list of per packet offloads.

11. The computer network system of claim 4, wherein said packet offload logic modules comprise an offload type for defining a parameter type of an offload a driver and a hardware device is expected to provide to said multi-packet transmission system.

12. An operating system kernel in a computer network, comprising:

a network subsystem;

a plurality of network devices;

a transport module to create a single consolidated transport header for multiple data packets in a multi-packet data block and for processing the multi-packet data block in a single transport cycle; and

a network module to compute checksums the multi-packet data block;

a multi-packet transmission module comprising a contiguous block of a plurality of header information with associated payload data information for transmitting said multi-packet data block as a single data transmission block in a single system call from said operating system kernel to a requesting one of said plurality of network devices, a data size of each of the multiple data packets is dynamically set according to data transfer parameters of the underlying kernel application program to avoid a breakdown of application data into maximum segment size data packets determined by a TCP module, prior to being transmitted through a network subsystem, wherein the multi-packet transmission module causes the single consolidated transport header information of data packets to be generated in a single buffer and appended to a second buffer containing the data packets to be transmitted through a network stack.

13. The operating system kernel of claim 12, wherein said multi-packet transmission module further comprises a packet offload logic module for defining device offload types for the multi-packet transmission system.

14. The operating system kernel of claim 13, wherein said multi-packet transmission module further comprises header length information for defining space to set aside in main memory from the beginning of a current packet header to the beginning of the current layers header to enable the multi-packet transmission system to traverse a protocol stack in said network system.

15. The operating system kernel of claim 14, wherein said packet information logic module further comprises packet tail length information for defining a space set aside in said main memory from the end of a current layer header to the end of the space set aside for the current packet header.

16. The operating system kernel of claim 15, wherein said packet information logic module further comprises packet header offset information for defining header offset information relative to the base of the header buffer for calculating header input/output address posted to said network device for the current packet to be fetched by said network device and transmitted.

17. The operating system kernel of claim 16, wherein said packet information logic module further comprises packet header length information for defining a total length of all headers for a particular packet.

18. The operating system kernel of claim 17, wherein said packet information logic module further comprises offload offset information for defining a staffing offset for a list of per packet offloads.

19. The operating system kernel of claim 18, wherein said packet offload logic module comprises an offload type for defining the parameter type of an offload that a driver and a hardware device is expected to provide to said multi-packet transmission system.

20. A computer implemented multi-data request transmission system comprising:

data request primitive structure logic comprising information for transmitting header and payload information associated with a multi-packet data transmission request into layer 2 addressing packets, the information for transmitting header and payload include a packet header offset information for defining header offset information relative to the base of a header buffer for calculating header input/output address, and pointers to each of a plurality of data packets in the payload;

payload data logic for providing payload data information associated with each packet in said multi-packet data transmission request; and

packet header information logic for providing header information associated with each of said multi-packet data transmission requests, the header information includes a contiguous block of a plurality of header information with associated payload data information and a header length information for defining space to set aside in main memory from a beginning of current packet header to a beginning of a header of current layer to enable the multi-packet transmission system to traverse a protocol stack in the network system.

21. A system as described in claim 20 wherein said multi-data request transmission system further comprises a data buffer for storing a plurality of packets of data transmitted in a single transmission cycle to said network devices.

22. A system as described in claim 21 wherein said data is a kernel data structure of a computer operating system.

23. A system as described in claim 22 wherein application programs in said computer system are aware of said data buffer for said data structure.

24. A method of transmitting multiple packets in a computer system network to a network device in a single call to a data link layer in said computer network, the method comprising:

allocating a master block for a data payload to create a payload page that includes a plurality of payload data;

allocating header information and associated block data, the header information includes a contiguous block of a plurality of header information for the plurality of payload data and a header offset information relative to a base of a header buffer for calculating header input/output address;

generating header-payload pairs by linking said header information to a payload data, wherein the header information includes pointers to each of the plurality of payloads;

allocating a multi-data transmit descriptor and an associating memory block;

generating a contiguous data block corresponding to said multiple packets; and

transmitting said multi-packet data block to said device driver.

25. The method of claim 24, wherein said transmitting said multi-packet data block comprises generating duplicate network protocol stack messages to said network device.

26. The method of claim 25, wherein said transmitting said multi-packet data block further comprises locking down said header and payload information for a direct memory access in said computer network.

27. The method of claim 26, wherein said transmitting said multi-packet data block further comprises updating said network protocol stack with said header-payload pairs until said multi-data request is completely transmitted.