Inline Encryption hardware allows software to specify an encryption context
(an encryption key, crypto algorithm, data unit num, data unit size, etc.)
along with a data transfer request to a storage device, and the inline
encryption hardware will use that context to en/decrypt the data. The
inline encryption hardware is part of the storage device, and it
conceptually sits on the data path between system memory and the storage
device.
Inline Encryption hardware implementations often function around the
concept of "keyslots". These implementations often have a limited number
of "keyslots", each of which can hold an encryption context (we say that
an encryption context can be "programmed" into a keyslot). Requests made
to the storage device may have a keyslot associated with them, and the
inline encryption hardware will en/decrypt the data in the requests using
the encryption context programmed into that associated keyslot. As
keyslots are limited, and programming keys may be expensive in many
implementations, and multiple requests may use exactly the same encryption
contexts, we introduce a Keyslot Manager to efficiently manage keyslots.
The keyslot manager also functions as the interface that upper layers will
use to program keys into inline encryption hardware. For more information
on the Keyslot Manager, refer to documentation found in
block/keyslot-manager.c and linux/keyslot-manager.h.
Bug: 137270441
Test: tested as series; see I26aac0ac7845a9064f28bb1421eb2522828a6dec
Change-Id: I9a2dc72d61d5a3c64af379a97dd46155b41193eb
Signed-off-by: Satya Tangirala <satyat@google.com>
Link: https://patchwork.kernel.org/patch/11214713/