On Tue, Apr 02, 2024 at 02:26:17PM +0200, Christoph Hellwig wrote: > On Thu, Mar 28, 2024 at 04:39:01PM -0400, Stefan Hajnoczi wrote: > > In the block device world there are similar concepts to holes: > > - SCSI has Logical Block Provisioning where the "mapped" state would be > > considered data and other states would be considered holes. > > But for SCSI (and ATA and NVMe) unmapped/delallocated/etc blocks do > not have to return zeroes. They could also return some other > initialization pattern pattern. So they are (unfortunately) not a 1:1 > mapping to holes in sparse files. Hi Christoph, There is a 1:1 mapping when when the Logical Block Provisioning Read Zeroes (LBPRZ) field is set to xx1b in the Logical Block Provisioning VPD page. Otherwise SEEK_HOLE/SEEK_DATA has to treat the device as filled with data because it doesn't know where the holes are. Stefan
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