mmc: core: Improve RPMB frame handling code

Introduce RPMB_FRAME_SIZE, CHECK_SIZE_NEQ(), and CHECK_SIZE_ALIGNED()
macros to replace repetitive sizeof(struct rpmb_frame) checks in
mmc_route_rpmb_frames().

Signed-off-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Avri Altman <avri.altman@sandisk.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index e14820cde252918816f25e35cc6b77eaeb99fd81..a74e75df93b061d55e9e9a0c01e8ea76b155b2a1 100644 (file)
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -121,6 +121,10 @@ struct rpmb_frame {
 #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))
+
 static DEFINE_MUTEX(block_mutex);
 
 /*
@@ -2858,12 +2862,12 @@ static void set_idata(struct mmc_blk_ioc_data *idata, u32 opcode,
         * The size of an RPMB frame must match what's expected by the
         * hardware.
         */
-       BUILD_BUG_ON(sizeof(struct rpmb_frame) != 512);
+       static_assert(!CHECK_SIZE_NEQ(512), "RPMB frame size must be 512 bytes");
 
        idata->ic.opcode = opcode;
        idata->ic.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
        idata->ic.write_flag = write_flag;
-       idata->ic.blksz = sizeof(struct rpmb_frame);
+       idata->ic.blksz = RPMB_FRAME_SIZE;
        idata->ic.blocks = buf_bytes /  idata->ic.blksz;
        idata->buf = buf;
        idata->buf_bytes = buf_bytes;
@@ -2887,32 +2891,28 @@ static int mmc_route_rpmb_frames(struct device *dev, u8 *req,
        if (IS_ERR(md->queue.card))
                return PTR_ERR(md->queue.card);
 
-       if (req_len < sizeof(*frm))
+       if (req_len < RPMB_FRAME_SIZE)
                return -EINVAL;
 
        req_type = be16_to_cpu(frm->req_resp);
        switch (req_type) {
        case RPMB_PROGRAM_KEY:
-               if (req_len != sizeof(struct rpmb_frame) ||
-                   resp_len != sizeof(struct rpmb_frame))
+               if (CHECK_SIZE_NEQ(req_len) || CHECK_SIZE_NEQ(resp_len))
                        return -EINVAL;
                write = true;
                break;
        case RPMB_GET_WRITE_COUNTER:
-               if (req_len != sizeof(struct rpmb_frame) ||
-                   resp_len != sizeof(struct rpmb_frame))
+               if (CHECK_SIZE_NEQ(req_len) || CHECK_SIZE_NEQ(resp_len))
                        return -EINVAL;
                write = false;
                break;
        case RPMB_WRITE_DATA:
-               if (req_len % sizeof(struct rpmb_frame) ||
-                   resp_len != sizeof(struct rpmb_frame))
+               if (!CHECK_SIZE_ALIGNED(req_len) || CHECK_SIZE_NEQ(resp_len))
                        return -EINVAL;
                write = true;
                break;
        case RPMB_READ_DATA:
-               if (req_len != sizeof(struct rpmb_frame) ||
-                   resp_len % sizeof(struct rpmb_frame))
+               if (CHECK_SIZE_NEQ(req_len) || !CHECK_SIZE_ALIGNED(resp_len))
                        return -EINVAL;
                write = false;
                break;
@@ -2920,10 +2920,8 @@ static int mmc_route_rpmb_frames(struct device *dev, u8 *req,
                return -EINVAL;
        }
 
-       if (write)
-               cmd_count = 3;
-       else
-               cmd_count = 2;
+       /* Write operations require 3 commands, read operations require 2 */
+       cmd_count = write ? 3 : 2;
 
        idata = alloc_idata(rpmb, cmd_count);
        if (!idata)
@@ -2937,7 +2935,7 @@ static int mmc_route_rpmb_frames(struct device *dev, u8 *req,
                          1 | MMC_CMD23_ARG_REL_WR, req, req_len);
 
                /* Send result request frame */
-               memset(resp_frm, 0, sizeof(*resp_frm));
+               memset(resp_frm, 0, RPMB_FRAME_SIZE);
                resp_frm->req_resp = cpu_to_be16(RPMB_RESULT_READ);
                set_idata(idata[1], MMC_WRITE_MULTIPLE_BLOCK, 1, resp,
                          resp_len);