From: Bean Huo <beanhuo@micron.com>

Move struct rpmb_frame and RPMB operation constants from MMC block
driver to include/linux/rpmb.h for reuse across different RPMB
implementations (UFS, NVMe, etc.).

Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/mmc/core/block.c | 42 ----------------------------------------
 include/linux/rpmb.h     | 42 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 42 deletions(-)

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index b32eefcca4b7..bd5f6fcb03af 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -79,48 +79,6 @@ MODULE_ALIAS("mmc:block");
 #define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16)
 #define MMC_EXTRACT_VALUE_FROM_ARG(x) ((x & 0x0000FF00) >> 8)
 
-/**
- * struct rpmb_frame - rpmb frame as defined by eMMC 5.1 (JESD84-B51)
- *
- * @stuff        : stuff bytes
- * @key_mac      : The authentication key or the message authentication
- *                 code (MAC) depending on the request/response type.
- *                 The MAC will be delivered in the last (or the only)
- *                 block of data.
- * @data         : Data to be written or read by signed access.
- * @nonce        : Random number generated by the host for the requests
- *                 and copied to the response by the RPMB engine.
- * @write_counter: Counter value for the total amount of the successful
- *                 authenticated data write requests made by the host.
- * @addr         : Address of the data to be programmed to or read
- *                 from the RPMB. Address is the serial number of
- *                 the accessed block (half sector 256B).
- * @block_count  : Number of blocks (half sectors, 256B) requested to be
- *                 read/programmed.
- * @result       : Includes information about the status of the write counter
- *                 (valid, expired) and result of the access made to the RPMB.
- * @req_resp     : Defines the type of request and response to/from the memory.
- *
- * The stuff bytes and big-endian properties are modeled to fit to the spec.
- */
-struct rpmb_frame {
-	u8     stuff[196];
-	u8     key_mac[32];
-	u8     data[256];
-	u8     nonce[16];
-	__be32 write_counter;
-	__be16 addr;
-	__be16 block_count;
-	__be16 result;
-	__be16 req_resp;
-} __packed;
-
-#define RPMB_PROGRAM_KEY       0x1    /* Program RPMB Authentication Key */
-#define RPMB_GET_WRITE_COUNTER 0x2    /* Read RPMB write counter */
-#define RPMB_WRITE_DATA        0x3    /* Write data to RPMB partition */
-#define RPMB_READ_DATA         0x4    /* Read data from RPMB partition */
-#define RPMB_RESULT_READ       0x5    /* Read result request  (Internal) */
-
 #define RPMB_FRAME_SIZE        sizeof(struct rpmb_frame)
 #define CHECK_SIZE_NEQ(val) ((val) != sizeof(struct rpmb_frame))
 #define CHECK_SIZE_ALIGNED(val) IS_ALIGNED((val), sizeof(struct rpmb_frame))
diff --git a/include/linux/rpmb.h b/include/linux/rpmb.h
index cccda73eea4d..25b69ecf5392 100644
--- a/include/linux/rpmb.h
+++ b/include/linux/rpmb.h
@@ -61,6 +61,48 @@ struct rpmb_dev {
 
 #define to_rpmb_dev(x)		container_of((x), struct rpmb_dev, dev)
 
+/**
+ * struct rpmb_frame - RPMB frame structure for authenticated access
+ *
+ * @stuff        : stuff bytes
+ * @key_mac      : The authentication key or the message authentication
+ *                 code (MAC) depending on the request/response type.
+ *                 The MAC will be delivered in the last (or the only)
+ *                 block of data.
+ * @data         : Data to be written or read by signed access.
+ * @nonce        : Random number generated by the host for the requests
+ *                 and copied to the response by the RPMB engine.
+ * @write_counter: Counter value for the total amount of the successful
+ *                 authenticated data write requests made by the host.
+ * @addr         : Address of the data to be programmed to or read
+ *                 from the RPMB. Address is the serial number of
+ *                 the accessed block (half sector 256B).
+ * @block_count  : Number of blocks (half sectors, 256B) requested to be
+ *                 read/programmed.
+ * @result       : Includes information about the status of the write counter
+ *                 (valid, expired) and result of the access made to the RPMB.
+ * @req_resp     : Defines the type of request and response to/from the memory.
+ *
+ * The stuff bytes and big-endian properties are modeled to fit to the spec.
+ */
+struct rpmb_frame {
+	u8     stuff[196];
+	u8     key_mac[32];
+	u8     data[256];
+	u8     nonce[16];
+	__be32 write_counter;
+	__be16 addr;
+	__be16 block_count;
+	__be16 result;
+	__be16 req_resp;
+} __packed;
+
+#define RPMB_PROGRAM_KEY       0x1    /* Program RPMB Authentication Key */
+#define RPMB_GET_WRITE_COUNTER 0x2    /* Read RPMB write counter */
+#define RPMB_WRITE_DATA        0x3    /* Write data to RPMB partition */
+#define RPMB_READ_DATA         0x4    /* Read data from RPMB partition */
+#define RPMB_RESULT_READ       0x5    /* Read result request  (Internal) */
+
 #if IS_ENABLED(CONFIG_RPMB)
 struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev);
 void rpmb_dev_put(struct rpmb_dev *rdev);
-- 
2.34.1

On 9/15/25 2:46 PM, Bean Huo wrote:
> + * @stuff        : stuff bytes

The above sounds vague to me ...

> +struct rpmb_frame {
> +	u8     stuff[196];
> +	u8     key_mac[32];
> +	u8     data[256];
> +	u8     nonce[16];
> +	__be32 write_counter;
> +	__be16 addr;
> +	__be16 block_count;
> +	__be16 result;
> +	__be16 req_resp;
> +} __packed;

Applying __packed to a data structure in its entirety is a bad practice
because it prevents the compiler from generating optimal code for
accessing multi-byte members on architectures that do not support
unaligned accesses. Please only apply __packed to the members that need
it and consider checking the size of the data structure with
static_assert().

Thanks,

Bart.