firmware: samsung: acpm: Annotate rx_data->cmd with __counted_by_ptr

Rename the `n_cmd` member of `struct acpm_rx_data` to `cmdcnt` to
maintain consistent nomenclature across the driver (aligning with
`txcnt`, `rxcnt`, and transfer helpers).

With the member renamed, annotate the dynamically allocated `cmd`
pointer with the `__counted_by_ptr(cmdcnt)` macro to improve runtime
bounds checking.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Link: https://patch.msgid.link/20260515-acpm-tmu-helpers-v2-2-8ca011d5a965@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index ec0929882b74e26912c8f505386a54b11cd5ba4c..69bb1008d1c0ffa33d9d1f832858b3e7e5e62070 100644 (file)
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -104,14 +104,14 @@ struct acpm_queue {
  * struct acpm_rx_data - RX queue data.
  *
  * @cmd:       pointer to where the data shall be saved.
- * @n_cmd:     number of 32-bit commands.
+ * @cmdcnt:    allocated capacity of the @cmd buffer in 32-bit words.
  * @rxcnt:     expected length of the response in 32-bit words.
  * @completed: flag indicating if the firmware response has been fully
  *             processed.
  */
 struct acpm_rx_data {
-       u32 *cmd;
-       size_t n_cmd;
+       u32 *cmd __counted_by_ptr(cmdcnt);
+       size_t cmdcnt;
        size_t rxcnt;
        bool completed;
 };
@@ -428,7 +428,7 @@ static int acpm_prepare_xfer(struct acpm_chan *achan,
        /* Clear data for upcoming responses */
        rx_data = &achan->rx_data[bit];
        rx_data->completed = false;
-       memset(rx_data->cmd, 0, sizeof(*rx_data->cmd) * rx_data->n_cmd);
+       memset(rx_data->cmd, 0, sizeof(*rx_data->cmd) * rx_data->cmdcnt);
        /* zero means no response expected */
        rx_data->rxcnt = xfer->rxcnt;
 
@@ -580,19 +580,19 @@ static int acpm_achan_alloc_cmds(struct acpm_chan *achan)
 {
        struct device *dev = achan->acpm->dev;
        struct acpm_rx_data *rx_data;
-       size_t cmd_size, n_cmd;
+       size_t cmd_size, cmdcnt;
        int i;
 
        if (achan->mlen == 0)
                return 0;
 
        cmd_size = sizeof(*(achan->rx_data[0].cmd));
-       n_cmd = DIV_ROUND_UP_ULL(achan->mlen, cmd_size);
+       cmdcnt = DIV_ROUND_UP_ULL(achan->mlen, cmd_size);
 
        for (i = 0; i < ACPM_SEQNUM_MAX; i++) {
                rx_data = &achan->rx_data[i];
-               rx_data->n_cmd = n_cmd;
-               rx_data->cmd = devm_kcalloc(dev, n_cmd, cmd_size, GFP_KERNEL);
+               rx_data->cmdcnt = cmdcnt;
+               rx_data->cmd = devm_kcalloc(dev, cmdcnt, cmd_size, GFP_KERNEL);
                if (!rx_data->cmd)
                        return -ENOMEM;
        }