File system adapter for hardware implementation or acceleration of file system functions

#The present invention relates to operating system functions and hardware implementation or acceleration of such functions.

#Operating systems in computers enable the computers to communicate with external resources. The operating system typically handles direct control of items associated with computer usage including keyboard, display, disk storage, network facilities, printers, modems, etc. The operating system in a computer is typically designed to cause the central processing unit (“CPU”) to perform tasks including the managing of local and network file systems, memory, peripheral device drivers, and processes including application processes. Placing responsibility for all of these functions on the CPU imposes significant processing burdens on it, particularly when the operating system is sophisticated, as, for example, in the case of Windows NT (available from Microsoft Corporation, Redmond, Wash.), Unix (available from many sources, including from SCO Software, Santa Cruz, Calif., and, in a version called “Linux” from Red Hat Software, Cambridge, Mass.), and NetWare (available from Novell, Provo, Utah). The more the burden is placed on the CPU to run processes other than those associated with applications, the less CPU time is available to run applications with the result that performance of the applications may be degraded. In addition, the throughput of devices external to the CPU is subject to the limitations imposed by the CPU when the operating system places responsibility for managing these devices on the CPU. Furthermore, reliability of the overall software-hardware system, including the CPU, running the operating system, in association with the devices, will depend, among other things, on the operating system. Owing to the inherent complexity of the operating system, unforeseen conditions may arise which may undermine stability of the overall software-hardware system.

#In one aspect of the invention, there is provided apparatus for handling service requests over a network, wherein the network utilizes a protocol. The apparatus includes a network subsystem (a) for receiving, via a network receive interface, service requests using the network protocol and forwarding such requests to a service output and (b) for receiving, via a service input, data to satisfy network requests and transmitting, via a network transmit interface, such data using the network protocol. The apparatus also includes a service subsystem having (a) a service request receive interface coupled to the service output of the network subsystem and (b) a service request transmit interface coupled to the service input of the network subsystem for delivering data to the network subsystem satisfying the network service requests. In this aspect, a first data path runs in a first direction from the network receive interface through the network subsystem via the service output to the service subsystem and a second data path runs in a second direction from the service subsystem into the network subsystem at the service input and through the network subsystem to the network transmit interface. The network subsystem and the service subsystem may be implemented on a single circuit board or on separate circuit boards. The protocol may include IP.

#The foregoing features of the invention will be more readily understood by reference to the following detailed description, taken with reference to the accompanying drawings, in which:

#FIG. 1 is a schematic representation of an embodiment of the present invention configured to provide network services, such as a file server or a web server;

#FIG. 2 is a block diagram of the embodiment illustrated in FIG. 1;

#For the purpose of the present description and the accompanying claims, the following terms shall have the indicated meanings unless the context otherwise requires:

#A “hardware-implemented subsystem” means a subsystem wherein major subsystem functions are performed in dedicated hardware that operates outside the immediate control of a software program. Note that such a subsystem may interact with a processor that is under software control, but the subsystem itself is not immediately controlled by software. “Major” functions are the ones most frequently used.

#A “hardware-accelerated subsystem” means one wherein major subsystem functions are carried out using a dedicated processor and dedicated memory, and, additionally (or alternatively), special purpose hardware; that is, the dedicated processor and memory are distinct from any central processor unit (CPU) and memory associated with the CPU.