1. A method comprising: receiving, by a deduplication computing system having an in-place-update file system, a data write request to write a block of data from a volatile memory to a non-volatile memory of the deduplication computing system, wherein blocks of data written to a location in non-volatile memory using the in-place-update file system are read and updated from the location; determining, by the deduplication computing system, whether the data write request is to perform an in-place update of an existing block of data in the non-volatile memory; when the data write request is to perform the in-place update of the existing block, the deduplication computing system: converting a type of write operation associated with the request from a requested write operation type to a new data allocation write operation; and processing the new data allocation write operation to write the block of data from the volatile memory to the non-volatile memory using an ordered sequence of file system data journaling and writes to the non-volatile memory comprising: allocating a new block of data in the non-volatile memory and writing the block of data from the volatile memory to the allocated new block, writing one or more entries to a file system journal of the in-place-update file system indicating one or more updates to deduplication metadata and an index node that occur as a result of the data write request were completed as an in-place update, wherein the one or more entries written to the journal enable data inconsistency correction in the non-volatile memory using the one or more entries in the event of an unclean shutdown of the deduplication computing system, and after the one or more entries are written to the file system journal, writing updated metadata and an updated inode to the non-volatile memory of the in-place-update file system to refer to the allocated new block of data.