US 11,860,947 B2
Deleted data restoration
Michael J. Koester, Hollister, CA (US); Kevin L Miner, Lake City, FL (US); Raymond E. Garcia, San Jose, CA (US); and Richard A. Schaeffer, Antioch, CA (US)
Assigned to INTERNATIONAL BUSINESS MACHINES CORPORATION, Armonk, NY (US)
Filed by International Business Machines Corporation, Armonk, NY (US)
Filed on Jan. 31, 2019, as Appl. No. 16/264,586.
Prior Publication US 2020/0250050 A1, Aug. 6, 2020
Int. Cl. G06F 16/903 (2019.01); G06F 16/16 (2019.01)
CPC G06F 16/90335 (2019.01) [G06F 16/164 (2019.01)] 17 Claims
OG exemplary drawing
 
1. A method, comprising operations of a processor in a host of a computing system having a host and a storage system, the operations comprising:
receiving a search request to identify data of a data unit of a file deleted from the storage system by erasure of location identifying metadata associated with the deleted data unit wherein erased identifying metadata no longer resides in storage space of the storage system, wherein data of the deleted data unit still resides in storage space of the storage system and wherein the search request includes specified search parameters;
in response to the search request, scanning data subunits of storage space including unallocated storage space of the storage system to identify storage space locations of scanned storage space meeting specified search parameters of the search request and containing data of the deleted data unit of the file; and
restoring erased location identifying metadata associated with identified storage space locations to undelete the data unit so that restored location identifying metadata remaps identified storage space locations to the data unit of the storage system wherein the restoring erased identifying metadata includes rebuilding erased location identifying metadata as a function of identified storage space locations to provide rebuilt location identifying metadata identifying a storage space location containing data of undeleted identified storage space records of the data unit of the file;
wherein erased metadata includes erased pointers which prior to erasure, identified a storage space location containing data of the deleted data unit, and wherein the restoring identifying metadata includes rebuilding erased pointers as a function of identified storage space locations to provide rebuilt pointers identifying a storage space location containing data of undeleted identified storage space records.