Abstract: Systems and methods are disclosed for data validation for zero copy protocols. In some examples, a server may include hardware, software, or a combination thereof to provide flexibility and data validation for a read request operation of a zero copy protocol. A read request operation can include a validation request frame, a status response frame, or both. In further examples, the validation request frame, the status response frame, or both can be configured by a requesting device to facilitate read data validation. In yet further examples, another device can receive a read request operation with a variably configured validation request frame, status response frame, or both and configure one or more data validation processes based on such.

Abstract: Methods and structure for emulating wide ports at an expander are provided. An exemplary system includes a Serial Attached Small Computer System Interface (SAS) expander. The expander includes a plurality of physical links, and a controller. The controller is able to identify a physical link coupled with a device, to generate a plurality of virtual physical links that are configured as a virtual wide port coupled with the device, and to present the virtual wide port at the expander in place of the physical link.

Abstract: Methods and structure for preemptively terminating Serial Attached Small Computer System Interface connections are provided. One exemplary embodiment includes an expander comprising multiple physical links, switching circuitry able to establish connections between end devices coupled with the expander through the physical links, and a connection manager. The connection manager is able to process an Open Address Frame from an end device, and to determine that the Open Address Frame requests a connection through a physical link that is already servicing an established connection. The connection manager is further able to determine that the Open Address Frame requests a higher priority connection than the established connection, and to direct one of the end devices utilizing the established connection to terminate the established connection based on the higher priority.

Abstract: Systems and methods herein provide for managing devices through a Serial Attached Small Computer System Interface (SAS) expander. The SAS expander includes a processor adapted to detect deadlock conditions in a SAS environment. In one embodiment, the SAS expander is operable to detect an Open Address Frame associated with a connection request from a source device to a destination device. The Open Address Frame includes a source address and a destination address associated with the source device and the destination device, respectively. The expander receives an arbitration in progress status on a partial pathway that is associated with the connection request. The expander is further operable to modify the Open Address Frame to include a deadlock indicator and forward the modified Open Address Frame on the partial pathway. When the modified Open Address Frame is received, the expander initiates pathway recovery upon determination that the deadlock indicator is valid.

Abstract: Methods and structure for emulating wide ports at an expander are provided. An exemplary system includes a Serial Attached Small Computer System Interface (SAS) expander. The expander includes a plurality of physical links, and a controller. The controller is able to identify a physical link coupled with a device, to generate a plurality of virtual physical links that are configured as a virtual wide port coupled with the device, and to present the virtual wide port at the expander in place of the physical link.

Abstract: Methods and apparatus for enabling Fast Context Switching (FCS) operation of an enhanced Serial Attached SCSI (SAS) expander and initiator for switching between one or more concurrently established connections including at least one Serial Advanced Technology Attachment (SATA) target device connection. Features and aspects hereof provide for enhanced logic within a SAS expander and/or initiator to detect the completion of an exchange over a first connection between an initiator device and a SATA target device and to allow switching to another (a second) connection without closing the first connection.

Abstract: Systems and methods herein provide for managing connection requests through a Serial Attached Small Computer System Interface (SAS) expander. In one embodiment, the expander receives a low priority open address frame (OAF) that includes a source address and a destination address. The expander also receives a high priority OAF that includes a source address and a destination address. The high priority OAF requires at least a portion of a partial path acquired by the low priority OAF for which connection request arbitration is in progress. The expander determines whether the high OAF source address matches the low OAF destination address, and in response to a determination that the high OAF source address is different than the low OAF destination address, acquires pathway resources from the low priority OAF and forwards the high priority OAF in accordance with its destination address.

Abstract: Systems and methods herein provide for managing devices through a Serial Attached Small Computer System Interface (SAS) expander. The SAS expander includes a processor adapted to detect deadlock conditions in a SAS environment. In one embodiment, the SAS expander is operable to detect an Open Address Frame associated with a connection request from a source device to a destination device. The Open Address Frame includes a source address and a destination address associated with the source device and the destination device, respectively. The expander receives an arbitration in progress status on a partial pathway that is associated with the connection request. The expander is further operable to modify the Open Address Frame to include a deadlock indicator and forward the modified Open Address Frame on the partial pathway. When the modified Open Address Frame is received, the expander initiates pathway recovery upon determination that the deadlock indicator is valid.

Abstract: Methods and structure for preemptively terminating Serial Attached Small Computer System Interface connections are provided. One exemplary embodiment includes an expander comprising multiple physical links, switching circuitry able to establish connections between end devices coupled with the expander through the physical links, and a connection manager. The connection manager is able to process an Open Address Frame from an end device, and to determine that the Open Address Frame requests a connection through a physical link that is already servicing an established connection. The connection manager is further able to determine that the Open Address Frame requests a higher priority connection than the established connection, and to direct one of the end devices utilizing the established connection to terminate the established connection based on the higher priority.

Abstract: Methods and apparatus for enabling Fast Context Switching (FCS) operation of an enhanced Serial Attached SCSI (SAS) expander and initiator for switching between one or more concurrently established connections including at least one Serial Advanced Technology Attachment (SATA) target device connection. Features and aspects hereof provide for enhanced logic within a SAS expander and/or initiator to detect the completion of an exchange over a first connection between an initiator device and a SATA target device and to allow switching to another (a second) connection without closing the first connection.