Merge "Merge fbe changes from upstream 5.4"

- The bio's encryption context is programmed into a keyslot in the KSM of the

  request queue that the bio is being submitted to (or the crypto API fallback

  KSM if the request queue doesn't have a KSM), and that the ``processing_ksm``

  KSM if the request queue doesn't have a KSM), and that the ``bc_ksm``

  in the ``bi_crypt_context`` is set to this KSM

- That the bio has its own individual reference to the keyslot in this KSM.

  ensuring that the bio has a valid reference to the keyslot when, for e.g., the

  crypto API fallback KSM in blk-crypto performs crypto on the device's behalf.

  The individual references are ensured by increasing the refcount for the

  keyslot in the ``processing_ksm`` when a bio with a programmed encryption

  keyslot in the ``bc_ksm`` when a bio with a programmed encryption

  context is cloned.

  request queue the bio is being submitted to (and if this KSM does not exist,

  then it will program it into blk-crypto's internal KSM for crypto API

  fallback). The KSM that this encryption context was programmed into is stored

  as the ``processing_ksm`` in the bio's ``bi_crypt_context``.

  as the ``bc_ksm`` in the bio's ``bi_crypt_context``.

**Case 2:** blk-crypto is given a bio whose encryption context has already been

programmed into a keyslot in the *crypto API fallback* KSM.

This way, when a device driver is processing a bio, it can be sure that

the bio's encryption context has been programmed into some KSM (either the

device driver's request queue's KSM, or blk-crypto's crypto API fallback KSM).

It then simply needs to check if the bio's processing_ksm is the device's

It then simply needs to check if the bio's ``bc_ksm`` is the device's

request queue's KSM. If so, then it should proceed with IE. If not, it should

simply do nothing with respect to crypto, because some other KSM (perhaps the

blk-crypto crypto API fallback KSM) is handling the en/decryption.

CONFIG_MD=y

CONFIG_BLK_DEV_DM=y

CONFIG_DM_CRYPT=y

CONFIG_DM_DEFAULT_KEY=y

CONFIG_DM_SNAPSHOT=y

CONFIG_DM_UEVENT=y

CONFIG_DM_VERITY=y

CONFIG_MD=y

CONFIG_BLK_DEV_DM=y

CONFIG_DM_CRYPT=y

CONFIG_DM_DEFAULT_KEY=y

CONFIG_DM_SNAPSHOT=y

CONFIG_DM_UEVENT=y

CONFIG_DM_VERITY=y

config BLK_INLINE_ENCRYPTION

	bool "Enable inline encryption support in block layer"

	help

	  Build the blk-crypto subsystem. Enabling this lets the

	  block layer handle encryption, so users can take

	  advantage of inline encryption hardware if present.

config BLK_INLINE_ENCRYPTION_FALLBACK

	bool "Enable crypto API fallback for blk-crypto"

	depends on BLK_INLINE_ENCRYPTION

	select CRYPTO

	select CRYPTO_BLKCIPHER

	help

	  Build the blk-crypto subsystem.

	  Enabling this lets the block layer handle encryption,

	  so users can take advantage of inline encryption

	  hardware if present.

	  Enabling this lets the block layer handle inline encryption

	  by falling back to the kernel crypto API when inline

	  encryption hardware is not present.

menu "Partition Types"