Abstract: A storage device controller coupled to a storage device having a multiple locations for storing data coupled to may receive a WRITE ANYWHERE command including write data but not specifying a location of the storage device where the write data should be stored. The controller responds to the WRITE ANYWHERE command by selecting one or more unused locations of the storage device, and writing the write data in the one or more unused locations of the storage device. After writing the write data to the storage device, the controller may report where the write data is stored to the host. The host may also issue FREE commands to the controller specifying locations of the storage device which should be identified as unused. In response to a received FREE command, the controller may store information in a memory indicating that the location specified by the FREE command is unused.

Abstract: In a method for partitioning SAS storage within a blade server chassis, where the blade server chassis may include one of a plurality (N) of server blades, the same plurality (N) of SAS storage blades or any combination thereof up to a total of N blades, in order for the plurality of SAS storage blades to be securely shared by the plurality of server blades, a pair-based zoning scheme may be implemented whereby if a server blade and a disk blade occupy neighboring slots in the blade server chassis, a pair of the server blade and the disk blade may be set to belong in the same zone. Partitioning of SAS expansion ports within the blade server chassis may be accomplished by providing exclusive access of a single SAS expansion port to a server blade located in an even slot.

Abstract: A storage array interconnection fabric may be configured using multiple independent paths. A storage system including a plurality of communication paths is configured for connecting each node of a plurality of nodes forming an interconnection fabric. Each of the communications paths is an independent communications path. In addition, a first portion of the plurality of nodes is configured to communicate with a plurality of mass storage devices such as disk drives. A second portion of the plurality of nodes may be configured to communicate with a host.

Abstract: A method may involve: receiving an even number of odd-sized packets for transmission over a double data rate link; re-packetizing the even number of odd-sized packets into several even-sized packets; transmitting the even-sized packets over the double data rate link; and de-packetizing the even-sized packets to reform the even number of odd-sized packets. Re-packetizing may involve dividing each of the even number of odd-sized packets into an even-sized portion and a remaining portion. Each even-sized portion may be transferred as one of the even-sized packets. The remaining portions of each of the even number of odd-sized packets may be combined to form another one of even-sized packets. De-packetizing may involve associating each of several portions of one of the even-sized packets with a respective other one of the even-sized packets.

Abstract: Systems and methods for routing messages in an interconnection fabric are provided. The fabric includes a plurality of nodes, each node having, for example, four ports coupled to adjacent nodes in the fabric. A source node initiating a message in the fabric can transmit the message out of one of its four ports. Between a source node and a destination node, there are at least four independent paths which may be taken, depending on the output port from the source node. However, the precise path is not expressly delineated in the message. Instead, the message contains the address of the destination node, the address of the originating node, and a target region for the message. Each intermediate node is configured to receive a message via one of its four ports, and then select an appropriate output port based on the location of the port which received the message combined with the address and target information contained in the message.

Abstract: A storage system comprises a storage array controller and a storage array, which includes multiple storage devices and disk drive controllers. The storage array controller issues scrubbing operation commands to one or more of the disk drive controllers. In response, each disk drive controller that receives a scrubbing operation command reads data from within a data range from at least one of the disk drives, calculates a new checksum for the data, and compares the new checksum to a preexisting checksum for the data. If the new checksum doesn't equal the preexisting checksum, the data within the data range is determined to be erroneous.

Abstract: Various embodiments of systems and methods for performing write cache mirroring may involve accessing different mapped regions within a memory. The memory controller may automatically mirror write requests to another memory. Write requests targeting one mapped region may be verified such that local completion of the write indicates that the mirrored write has also completed. Write requests targeting another mapped region may be unverified. Unverified writes may be verified by performance of a verified write.

Abstract: A storage system comprises a storage array controller and a storage array, which includes multiple disk drives and disk drive controllers. The storage array controller issues scrubbing operation commands to one or more of the disk drive controllers. In response, each disk drive controller that receives a scrubbing operation command reads data from within a data range from at least one of the disk drives, calculates a new checksum for the data, and compares the new checksum to a preexisting checksum for the data. If the new checksum doesn't equal the preexisting checksum, the data within the data range is determined to be erroneous.

Abstract: Various embodiments of systems and methods for implementing a streaming I/O protocol are disclosed. In some embodiments, a method may involve: receiving a packet initiating a streaming write operation, where the packet indicates that the size of the streaming write is larger than the size of the packet; initiating a write access having a size larger than the size of the packet to a storage device; receiving subsequent packets included in the streaming write operation; and writing data received in the subsequent packets to the storage device as part of the write access initiated in response to the earlier packet. In some embodiments, streaming read operations may also be supported.

Abstract: A method may involve: receiving a request to perform a block write to a target device and data associated with the block write; buffering the data associated with the block write prior to completing the block write to the target device; storing an indication identifying a block address range of the block write; receiving a request to perform a read to the target device; and determining whether an address of the read is within the block address range of the block write identified by the indication. In some embodiments, such a method may allow the read to complete ahead of the block write dependent on whether the address of the read is within the block address range of the block write identified by the indication.

Abstract: A single field replaceable storage or computer system may include a processor coupled to a peripheral bus by a bridge device. The field replaceable unit (FRU) may also include system memory coupled to the processor and a network interface coupled to the peripheral bus. One or more drive controllers may also be included coupled to the peripheral bus. Additionally, the single field replaceable unit includes an array of disk drives coupled to the one or more drive controllers. The array of disk drives may be configured as one or more RAID logical volumes and exported or presented to client machines as one or more file systems through the network interface. The processor, system memory, network interface, drive controllers, and array of disk drives are all packaged together as a single field replaceable unit. The processor, system memory, network interface, drive controllers, and array of disk drives may be configured not to be individually field serviceable or replaceable.

Abstract: Data integrity errors in a redundant storage array are handled by storing a plurality of data blocks having a horizontal redundant relationship and storing a plurality of checksums, each checksum having a vertical redundant relationship with a corresponding one of the plurality of data blocks. In response to detection of a data integrity error in at least one of the plurality of data blocks, the vertical redundant relationships between each of the checksums in the plurality of checksums and the corresponding data blocks are reviewed and the horizontal redundant relationship between the data block having the data integrity error and the remaining data blocks in the plurality of data blocks is also reviewed. The results of these reviews of the redundant relationships can be used to diagnose and repair the data integrity error.

Abstract: Various embodiments of systems and methods for implementing shared memory regions in a distributed shared memory system may involve implementing several different shared memory regions in each distributed shared memory node. Each node may reflect write access requests targeting those shared memory regions to one or more other nodes, depending on which shared region is targeted (e.g., requests targeting one region may be reflected to a single other node while requests targeting other regions may be reflected to more than one other node). A node's completion of the requested write access locally may be dependent on the completion of the write access in the other nodes, depending on which shared memory region is targeted.

Abstract: Resources may be shared between multiple controllers configured to access those resources by associating a portion of a semaphore shared memory region with each different shared resource. Whenever a local write request to the portion of the semaphore shared memory region is detected by a memory controller, the memory controller may broadcast the write request to other remote memory controllers. The memory controller may delay performing a memory access to a local copy of that portion of the semaphore shared memory region until the other memory controllers have performed the write access to their copy of the semaphore shared memory region. The values stored in the semaphore shared memory region indicate which controller currently has access to the shared resource.

Abstract: Various embodiments of systems and methods for implementing a streaming I/O protocol are disclosed. In some embodiments, a method may involve: receiving a packet initiating a streaming write operation, where the packet indicates that the size of the streaming write is larger than the size of the packet; initiating a write access having a size larger than the size of the packet to a storage device; receiving subsequent packets included in the streaming write operation; and writing data received in the subsequent packets to the storage device as part of the write access initiated in response to the earlier packet. In some embodiments, streaming read operations may also be supported.

Abstract: A system may include mirroring logic, a controller, and first and second devices (e.g., data storage devices). The first and second devices may include multiple registers. The mirroring logic may be configured in a first mode wherein the mirroring logic allows the registers of the first device to be accessed from the controller and prevents the registers of the second device from being accessed from the controller. The mirroring logic may be configured in a second mode wherein the mirroring logic allows the registers of the second device to be accessed from the controller and prevents the registers of the first device from being accessed. The first and second devices may be configured via the mirroring logic such that the first and second devices are selected simultaneously. When selected simultaneously, the first and second devices may carry out a subsequently issued command substantially simultaneously.

Abstract: Each node's memory controller may be configured to send and receive messages on a dedicated memory-to-memory interconnect according to the communication protocol and to responsively perform memory accesses in a local memory. The type of message sent on the interconnect may depend on which memory region is targeted by a memory access request local to the sending node. If certain regions are targeted locally, a memory controller may delay performance of a local memory access until the memory access has been performed remotely. Remote nodes may confirm performance of the remote memory accesses via the memory-to-memory interconnect.

Abstract: A storage device controller configured for coupling to a storage device (e.g., a hard disk drive) having a multiple locations for storing data. The controller is coupled to receive a WRITE ANYWHERE command including write data. Unlike a conventional write command, the WRITE ANYWHERE command does not specify a location of the storage device where the write data is to be stored. The controller responds to the WRITE ANYWHERE command by: (i) selecting one or more unused locations of the storage device, and (ii) writing the write data to the storage device, wherein the writing of the write data includes directing the storage device to store the write data in the one or more unused locations of the storage device. At least a portion of the write data in stored in each of the one or more unused locations. The controller may be coupled to receive the WRITE ANYWHERE command from a host configured to track usage of the locations of the storage device.

Abstract: A method may involve: receiving a request to perform a block write to a target device and data associated with the block write; buffering the data associated with the block write prior to completing the block write to the target device; storing an indication identifying a block address range of the block write; receiving a request to perform a read to the target device; and determining whether an address of the read is within the block address range of the block write identified by the indication. In some embodiments, such a method may allow the read to complete ahead of the block write dependent on whether the address of the read is within the block address range of the block write identified by the indication.

Abstract: A method may involve: receiving an even number of odd-sized packets for transmission over a double data rate link; re-packetizing the even number of odd-sized packets into several even-sized packets; transmitting the even-sized packets over the double data rate link; and de-packetizing the even-sized packets to reform the even number of odd-sized packets. Re-packetizing may involve dividing each of the even number of odd-sized packets into an even-sized portion and a remaining portion. Each even-sized portion may be transferred as one of the even-sized packets. The remaining portions of each of the even number of odd-sized packets may be combined to form another one of even-sized packets. De-packetizing may involve associating each of several portions of one of the even-sized packets with a respective other one of the even-sized packets.