# US 8,752,063 B2 · Programming interface for data communications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,752,063 B2 - Document ID: US8752063B2 - Status: Granted - Kind: B2 - Application number: 13/167,311 - Filed: 2011-06-23 - Published: 2012-12-27 - Granted: 2014-06-10 - Earliest claimed: 2011-06-23 - Assignees: Microsoft Corporation - Applicants: Osman N. Ertugay; Keith E. Horton; Joseph Nievelt - Inventors: Osman N. Ertugay; Keith E. Horton; Joseph Nievelt - Web page: https://patentgrep.com/patent/US8752063B2 ## CPC - G06F 9/544: {Buffers; Shared memory; Pipes} - G06F 9/545: {where tasks reside in different layers, e.g. user- and kernel-space} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract In embodiments of a programming interface for data communications, a request queue and a completion queue can be allocated from a user-mode virtual memory buffer that corresponds to an application. The request queue and the completion queue can be pinned to physical memory and then mapped to kernel-mode system addresses so that the request queue and the completion queue can be accessed by a kernel-mode execution thread. A request can be received from an application for the kernel to handle data in the request queue, and a system issued to the kernel for the kernel-mode execution thread to handle the request. The kernel-mode execution thread can then handle additional requests from the application without additional system calls being issued. ## Claims ### Claim 1 A computer-implemented method, comprising: registering a user-mode virtual memory buffer corresponding to an application; issuing a system call to a kernel for a kernel-mode execution thread to handle a request from the application; allocating a completion queue from the user-mode virtual memory buffer and pinning the completion queue to physical memory; mapping the completion queue to a first kernel-mode system address in the kernel, the completion queue configured to receive completion notifications from the kernel mode execution thread via the kernel-mode system address and to enable access to the completion notifications by the application via the user-mode virtual memory buffer; registering a socket configured to provide data requests from the application to the kernel, the registering the socket comprising: allocating a request queue from the user-mode virtual memory buffer and pinning the request queue to the physical memory; mapping the request queue to a second kernel-mode system address, the request queue configured to receive data from the application via the user-mode virtual memory buffer and to enable access to the data by the kernel-mode execution thread via the second kernel-mode system address; identifying the completion queue to the socket; and receiving an additional request from the application for the kernel-mode execution thread to handle additional data in the request queue, the kernel-mode execution thread handling the additional request without an additional system call being issued to the kernel. ### Claim 2 (depends on 1) A computer-implemented method as recited in claim 1, wherein the registering the user-mode virtual memory buffer further comprises sending a registration identifier of the buffer to the application. ### Claim 3 (depends on 2) A computer-implemented method as recited in claim 2, wherein the registering the user-mode virtual memory buffer comprises receiving a request from the application for the kernel to handle the data in the request queue, the request including the registration identifier of the buffer. ### Claim 4 (depends on 3) A computer-implemented method as recited in claim 3, wherein the kernel-mode execution thread is configured to handle the request by retrieving the data from the request queue via the second kernel-mode system address. ### Claim 5 (depends on 3) A computer-implemented method as recited in claim 3, further comprising receiving a completion notification in the completion queue, the completion notification posted in the completion queue by the kernel-mode execution thread via the kernel-mode virtual memory buffer when the request is handled. ### Claim 6 (depends on 5) A computer-implemented method as recited in claim 5, wherein the application is configured for: monitoring the completion queue via the user-mode virtual memory buffer to detect the completion notification posted by the kernel-mode execution thread, the completion notification indicating to the application that the request has been handled by the kernel-mode execution thread; and re-using the request queue for an additional request responsive to detecting the completion notification. ### Claim 7 A computing system, comprising: a memory configured to maintain an application that is executable; a processor to execute a programming interface that is configured to: receive a request from the application for a kernel to handle data in a request queue, the request queue allocated from a user-mode virtual memory buffer corresponding to the application; determine that a kernel-mode execution thread is not assigned to handle the request; and issue a system call to the kernel for a kernel-mode execution thread to handle the request, the kernel-mode execution thread further configured to handle additional requests from the application without the programming interface having to issue additional system calls to the kernel. ### Claim 8 (depends on 7) A computing system as recited in claim 7, wherein prior to receiving the request from the application, the programming interface is further configured to: allocate the request queue and a completion queue from the user-mode virtual memory buffer corresponding to the application; pin the request queue and the completion queue to physical memory; and map the request queue to a first kernel-mode system address and map the completion queue to a second kernel-mode system address to enable the request queue and the completion queue to be accessed by the kernel-mode execution thread. ### Claim 9 (depends on 8) A computing system as recited in claim 8, wherein the kernel-mode execution thread is configured to handle the request from the application by retrieving the data from the request queue via the first kernel-mode system address. ### Claim 10 (depends on 8) A computing system as recited in claim 8, wherein the completion queue is configured to receive a completion notification from the kernel-mode execution thread after the kernel-mode execution thread handles the request. ### Claim 11 (depends on 10) A computing system as recited in claim 10, wherein the application is configured to: monitor the completion queue via the user-mode virtual memory buffer to detect the completion notification posted by the kernel-mode execution thread, the completion notification indicating to the application that the request has been handled by the kernel-mode execution thread; and re-use the request queue for the additional requests responsive to detecting the completion notification. ### Claim 12 (depends on 11) A computing system as recited in claim 11, wherein the application is further configured to re-use the request queue for the additional requests without unpinning the request queue and the completion queue from the physical memory. ### Claim 13 A computing device, comprising: at least a memory and a processor to implement a programming interface, the programming interface configured to: allocate a request queue and a completion queue from a user-mode virtual memory buffer that corresponds to an application; pin the request queue and the completion queue to physical memory; map the request queue and the completion queue to kernel-mode system addresses in a kernel to enable the request queue and the completion queue to be accessed by a kernel-mode execution thread; receive a request from the application for the kernel to handle data in the request queue; issue a system call to the kernel for a kernel-mode execution thread to handle the request, the kernel-mode execution thread further configured to handle additional requests from the application; and receive the additional requests from the application for the kernel-mode execution thread to handle the data in the request queue, the kernel-mode execution thread configured to handle the additional requests without the programming interface issuing additional system calls. ### Claim 14 (depends on 13) A computing device as recited in claim 13, wherein the completion queue is configured to receive a completion notification from the kernel-mode execution thread after the kernel-mode execution thread handles the request. ### Claim 15 (depends on 14) A computing device as recited in claim 14, wherein the application is configured to: monitor the completion queue to detect the completion notification posted by the kernel-mode execution thread, the completion notification indicating to the application that the request has been handled by the kernel-mode execution thread; and re-use the request queue for the additional requests. ### Claim 16 (depends on 15) A computing device as recited in claim 15, wherein the application is further configured to re-use the request queue for the additional requests without unpinning the request queue and the completion queue from the physical memory.