Abstract: Aspects of the subject matter described herein relate to checkpoints for a file system. In aspects, updates to the file system are organized into checkpoint buckets. When a checkpoint is desired, subsequent updates are directed to another checkpoint bucket. After global tables have been updated for updates in the current checkpoint bucket, a logical copy of the global tables is created. This logical copy is stored as part of the checkpoint data. To assist in recovery, a checkpoint manager may wait until all updates of the current checkpoint bucket have been written to storage before writing final checkpoint data to storage. This final checkpoint data may refer to the logical copy of the global tables and include a validation code to verify that the checkpoint data is correct.

Abstract: Aspects of the subject matter described herein relate to checkpoints for a file system. In aspects, updates to the file system are organized into checkpoint buckets. When a checkpoint is desired, subsequent updates are directed to another checkpoint bucket. After global tables have been updated for updates in the current checkpoint bucket, a logical copy of the global tables is created. This logical copy is stored as part of the checkpoint data. To assist in recovery, a checkpoint manager may wait until all updates of the current checkpoint bucket have been written to storage before writing final checkpoint data to storage. This final checkpoint data may refer to the logical copy of the global tables and include a validation code to verify that the checkpoint data is correct.

Abstract: The present invention extends to methods, systems, and computer program products for licensing protected content to application sets. Embodiments of the invention permit a local machine to increase its participation in authorizing access to protected content. For example, an operating system within an appropriate computing environment is permitted to determine if an application is authorized to access protected content. Thus, the application is relieved from having to store a publishing license. Further, authorization decisions are partially distributed, easing the resource burden on a protection server. Accordingly, embodiments of the invention can facilitate more robust and efficient authorization decisions when access to protected content is requested.

Abstract: A method and a processing device are provided for sequentially aggregating data to a write log included in a volume of a random-access medium. When data of a received write request is determined to be suitable for sequentially aggregating to a write log, the data may be written to the write log and a remapping tree, for mapping originally intended destinations on the random-access medium to one or more corresponding entries in the write log, may be maintained and updated. At time periods, a checkpoint may be written to the write log. The checkpoint may include information describing entries of the write log. One or more of the checkpoints may be used to recover the write log, at least partially, after a dirty shutdown. Entries of the write log may be drained to respective originally intended destinations upon an occurrence of one of a number of conditions.

Abstract: A method and a processing device are provided for sequentially aggregating data to a write log included in a volume of a random-access medium. When data of a received write request is determined to be suitable for sequentially aggregating to a write log, the data may be written to the write log and a remapping tree, for mapping originally intended destinations on the random-access medium to one or more corresponding entries in the write log, may be maintained and updated. At time periods, a checkpoint may be written to the write log. The checkpoint may include information describing entries of the write log. One or more of the checkpoints may be used to recover the write log, at least partially, after a dirty shutdown. Entries of the write log may be drained to respective originally intended destinations upon an occurrence of one of a number of conditions.

Abstract: Aspects of the subject matter described herein relate to storage allocation. In aspects, a hierarchical data structure is used to track allocation data for storage managed by a file system. The hierarchical data structure may have multiple levels with each level having data regarding a different granularity of storage. Portions of the hierarchical data structure may be locked independently of other portions of the hierarchical data structure. The hierarchical data structure may indicate that one or more portions of storage are for exclusive use by a directory. Extra space may be reserved in allocated space in anticipation of subsequent operations. Allocation requestors may obtain storage allocation from regions associated with different levels of the hierarchical data structure.

Abstract: Aspects of the subject matter described herein relate to error detection for files. In aspects, before allowing updates to a clean file, a flag marking the file as dirty is written to non-volatile storage. Thereafter, the file may be updated as long as desired. Periodically or at some other time, the file may be marked as clean after all outstanding updates to the file and error codes associated with the file are written to storage. While waiting for outstanding updates and error codes to be written to storage, if additional requests to update the file are received, the file may be marked as dirty again prior to allowing the additional requests to update the file. The request to write a clean flag regarding the file may be done lazily.

Abstract: Aspects of the subject matter described herein relate to checkpoints for a file system. In aspects, updates to the file system are organized into checkpoint buckets. When a checkpoint is desired, subsequent updates are directed to another checkpoint bucket. After global tables have been updated for updates in the current checkpoint bucket, a logical copy of the global tables is created. This logical copy is stored as part of the checkpoint data. To assist in recovery, a checkpoint manager may wait until all updates of the current checkpoint bucket have been written to storage before writing final checkpoint data to storage. This final checkpoint data may refer to the logical copy of the global tables and include a validation code to verify that the checkpoint data is correct.

Abstract: A transactional logging service is provided to user-mode and kernel-mode log clients by utilizing a marshalling area to buffer a set of log records that a log client assembles into a log stream. Disk I/O (input/output) functionality is then separately brokered using a kernel-mode address space for a single dedicated physical log, or virtual logs multiplexed to a single log, which is written to stable storage that contains log records from across all of the log streams. Physical log writes are handled by a shared log flush queue and physical log reads are provided by a file system cache that underlies the service. A multi-level cache hierarchy is utilized when a log client needs to access a log record. A series of caches are queried in order of increasing latency until the targeted log record is located. The target log record is only read from disk in the event that it missed at each cache in the hierarchy.

Abstract: A processing device and a machine-implemented method may be provided for sequentially aggregating, or writing, data to a log included in a data store. The log may store multiple log entries. Each of the log entries may include an entry metadata portion, describing a respective log entry, and an entry payload data portion. The entry metadata portion may include a log sequence number, corresponding to a log entry at a particular position in the log. A library of log-related processes may be provided, along with an application program interface to permit a calling application program to call any of the log related processes. The log-related processes may be called during a boot mode, a user mode, and a kernel mode.

Abstract: A method and a processing device are provided for sequentially aggregating data to a write log included in a volume of a random-access medium. When data of a received write request is determined to be suitable for sequentially aggregating to a write log, the data may be written to the write log and a remapping tree, for mapping originally intended destinations on the random-access medium to one or more corresponding entries in the write log, may be maintained and updated. At time periods, a checkpoint may be written to the write log. The checkpoint may include information describing entries of the write log. One or more of the checkpoints may be used to recover the write log, at least partially, after a dirty shutdown. Entries of the write log may be drained to respective originally intended destinations upon an occurrence of one of a number of conditions.

Abstract: Aspects of the subject matter described herein relate to maintaining consistency in a storage system. In aspects, one or more objects may be updated in the context of a transaction. In conjunction with updating the objects, logical copies of the objects may be obtained and modified. A request to write the updated logical copies is sent to a storage controller. The logical copies do not overwrite the original copies. In conjunction with sending the request, a data structure is provided for the storage controller to store on the disk. The data structure indicates the one or more objects that were supposed to be written to disk and may include verification data to indicate the content that was supposed to be written to disk. During recovery, this data structure may be used to determine whether all of the object(s) were correctly written to disk.

Abstract: A method and a processing device are provided for sequentially aggregating data to a write log included in a volume of a random-access medium. When data of a received write request is determined to be suitable for sequentially aggregating to a write log, the data may be written to the write log and a remapping tree, for mapping originally intended destinations on the random-access medium to one or more corresponding entries in the write log, may be maintained and updated. At time periods, a checkpoint may be written to the write log. The checkpoint may include information describing entries of the write log. One or more of the checkpoints may be used to recover the write log, at least partially, after a dirty shutdown. Entries of the write log may be drained to respective originally intended destinations upon an occurrence of one of a number of conditions.

Abstract: For each of one or more existing nodes in a file system, pending notifications of updates that have been performed on the node can be identified and sent to one or more other nodes. The file system can be opened for use, and one or more other nodes can be updated in response to the pending notifications while the file system is open for use. For example, this may be done in an operation for recovering from a crash of the file system. Also, a process for dealing with stale data in container nodes in a file system can include processing access requests according to a stale data scheme.

Abstract: In response to a request to a file system to perform a requested update, a lock of a first node in a file system can be acquired, and an update of the first node can be performed while the lock of the first node is held. Also in response to the request, a lock of a second node can be acquired, and an update of the second node, which reflects the update of the first node, can be performed while the lock of the second node is held. The update of the first node can be independent of acquiring the lock of the second node. A file system can allow a pair of update operations to be performed in parallel where both operations include updating the same container node. Additionally, while a file system is running, new namespace types can be defined, and the file system can be extended to manage nodes within the new namespace types.

Abstract: A method and a processing device are provided for sequentially aggregating data to a write log included in a volume of a random-access medium. When data of a received write request is determined to be suitable for sequentially aggregating to a write log, the data may be written to the write log and a remapping tree, for mapping originally intended destinations on the random-access medium to one or more corresponding entries in the write log, may be maintained and updated. At time periods, a checkpoint may be written to the write log. The checkpoint may include information describing entries of the write log. One or more of the checkpoints may be used to recover the write log, at least partially, after a dirty shutdown. Entries of the write log may be drained to respective originally intended destinations upon an occurrence of one of a number of conditions.

Abstract: A processing device and a machine-implemented method may be provided for sequentially aggregating, or writing, data to a log included in a data store. The log may store multiple log entries. Each of the log entries may include an entry metadata portion, describing a respective log entry, and an entry payload data portion. The entry metadata portion may include a log sequence number, corresponding to a log entry at a particular position in the log. A library of log-related processes may be provided, along with an application program interface to permit a calling application program to call any of the log related processes. The log-related processes may be called during a boot mode, a user mode, and a kernel mode.

Abstract: Common block storage infrastructure techniques are described in which files are created through interaction with a file system to reserve extents in a volume on behalf of volume storage drivers, which may form a driver stack that resides logically on top of the volume. The files protect the reserved extents within the volume for use by the volume storage drivers, such as to store metadata related to operations performed by the drivers. When reserved extents are created, a location of the reserved extents is communicated through the driver stack to a corresponding volume storage driver. Volume storage drivers may also be configured to discover their corresponding reserved extents and communicate these to upper-level drivers and components. Accordingly, when a volume storage driver manipulates data in the volume, it may do so with awareness of the reserved extents of the other volume storage drivers.

Abstract: The present invention extends to methods, systems, and computer program products for licensing protected content to application sets. Embodiments of the invention permit a local machine to increase its participation in authorizing access to protected content. For example, an operating system within an appropriate computing environment is permitted to determine if an application is authorized to access protected content. Thus, the application is relieved from having to store a publishing license. Further, authorization decisions are partially distributed, easing the resource burden on a protection server. Accordingly, embodiments of the invention can facilitate more robust and efficient authorization decisions when access to protected content is requested.

Abstract: Kernel objects for implementing a transaction have a security descriptor applied thereto. The kernel objects include, at least, a transaction object, a resource management object, and an enlistment object. The security descriptor, otherwise known as an access control list, identifies at least one user, an operation to be performed on the kernel object to which the security descriptor is applied, and a right indicating that the identified user is permitted or prohibited to perform the operation.