Patent · US Expired

Reduced-overhead DMA

US6813652B2 · kind B2 · utility

29Cited by
12References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 19, 2004
Grant dateNov 2, 2004
Priority date
Expiry dateApr 19, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F13/28
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A plurality of direct memory access data transfers are accomplished to transfer data from a host to an adaptor. For each transfer, an indication of locations of at least one group of storage locations associated with the host available to hold the data to be transferred to the host is provided from the host to the adaptor. An indication of the provided indication is maintained, for that transfer, by the host. Based on the indication of locations provided from the host to the adaptor, data is transferred to the at least one group of storage locations from the adaptor. An indication is provided from the adaptor to the host that the data transferring step has been completed with respect to the at least one group of storage locations. The host determines the locations corresponding to the at least one group of storage locations based on the indications maintained by the host and retrieving the data from the at least one group of storage locations based on the determination. A similar method is provided to transfer data from the adaptor to the host. Broadly speaking, the host and adaptor retain state information between DMA data transfers. As a result, absolute values of overhead items …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.