Merge patch series "Basic inline encryption support for ufs-exynos"

Eric Biggers <ebiggers@kernel.org> says:

Add support for Flash Memory Protector (FMP), which is the inline
encryption hardware on Exynos and Exynos-based SoCs.

Specifically, add support for the "traditional FMP mode" that works on
many Exynos-based SoCs including gs101.  This is the mode that uses
"software keys" and is compatible with the upstream kernel's existing
inline encryption framework in the block and filesystem layers.  I
plan to add support for the wrapped key support on gs101 at a later
time.

Tested on gs101 (specifically Pixel 6) by running the 'encrypt' group
of xfstests on a filesystem mounted with the 'inlinecrypt' mount
option.

This patchset applies to v6.10-rc6, and it has no prerequisites that
aren't already upstream.

Link: https://lore.kernel.org/r/20240708235330.103590-1-ebiggers@kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/drivers/ufs/core/ufshcd-crypto.h b/drivers/ufs/core/ufshcd-crypto.h
index be8596f20ba2..89bb97c14c15 100644
--- a/drivers/ufs/core/ufshcd-crypto.h
+++ b/drivers/ufs/core/ufshcd-crypto.h
@@ -37,6 +37,33 @@ ufshcd_prepare_req_desc_hdr_crypto(struct ufshcd_lrb *lrbp,
 	h->dunu = cpu_to_le32(upper_32_bits(lrbp->data_unit_num));
 }
 
+static inline int ufshcd_crypto_fill_prdt(struct ufs_hba *hba,
+					  struct ufshcd_lrb *lrbp)
+{
+	struct scsi_cmnd *cmd = lrbp->cmd;
+	const struct bio_crypt_ctx *crypt_ctx = scsi_cmd_to_rq(cmd)->crypt_ctx;
+
+	if (crypt_ctx && hba->vops && hba->vops->fill_crypto_prdt)
+		return hba->vops->fill_crypto_prdt(hba, crypt_ctx,
+						   lrbp->ucd_prdt_ptr,
+						   scsi_sg_count(cmd));
+	return 0;
+}
+
+static inline void ufshcd_crypto_clear_prdt(struct ufs_hba *hba,
+					    struct ufshcd_lrb *lrbp)
+{
+	if (!(hba->quirks & UFSHCD_QUIRK_KEYS_IN_PRDT))
+		return;
+
+	if (!(scsi_cmd_to_rq(lrbp->cmd)->crypt_ctx))
+		return;
+
+	/* Zeroize the PRDT because it can contain cryptographic keys. */
+	memzero_explicit(lrbp->ucd_prdt_ptr,
+			 ufshcd_sg_entry_size(hba) * scsi_sg_count(lrbp->cmd));
+}
+
 bool ufshcd_crypto_enable(struct ufs_hba *hba);
 
 int ufshcd_hba_init_crypto_capabilities(struct ufs_hba *hba);
@@ -54,6 +81,15 @@ static inline void
 ufshcd_prepare_req_desc_hdr_crypto(struct ufshcd_lrb *lrbp,
 				   struct request_desc_header *h) { }
 
+static inline int ufshcd_crypto_fill_prdt(struct ufs_hba *hba,
+					  struct ufshcd_lrb *lrbp)
+{
+	return 0;
+}
+
+static inline void ufshcd_crypto_clear_prdt(struct ufs_hba *hba,
+					    struct ufshcd_lrb *lrbp) { }
+
 static inline bool ufshcd_crypto_enable(struct ufs_hba *hba)
 {
 	return false;