Replace the embedded `struct acpm_ops` inside `struct acpm_handle` with a pointer to a `const struct acpm_ops`.
Previously, the operations structure was embedded directly within the handle and populated dynamically at runtime via `acpm_setup_ops()`. This resulted in mutable function pointers and unnecessary per-instance memory overhead. By defining `exynos_acpm_driver_ops` statically as a `const` structure, the function pointers are now safely housed in the read-only `.rodata` section. This improves security by preventing function pointer overwrites, saves memory, and slightly reduces initialization overhead in `acpm_probe()`. Consequently, update all consumer drivers (clk, mfd) to access the operations via the new pointer indirection (`->ops->`). Finally, fix the previously empty kernel-doc description for the ops member to reflect its new pointer nature. Signed-off-by: Tudor Ambarus <[email protected]> --- drivers/clk/samsung/clk-acpm.c | 8 ++--- drivers/firmware/samsung/exynos-acpm.c | 36 ++++++++++------------ drivers/mfd/sec-acpm.c | 6 ++-- .../linux/firmware/samsung/exynos-acpm-protocol.h | 4 +-- 4 files changed, 25 insertions(+), 29 deletions(-) diff --git a/drivers/clk/samsung/clk-acpm.c b/drivers/clk/samsung/clk-acpm.c index 93667777094c..953ca8d5720a 100644 --- a/drivers/clk/samsung/clk-acpm.c +++ b/drivers/clk/samsung/clk-acpm.c @@ -68,8 +68,8 @@ static unsigned long acpm_clk_recalc_rate(struct clk_hw *hw, { struct acpm_clk *clk = to_acpm_clk(hw); - return clk->handle->ops.dvfs.get_rate(clk->handle, clk->mbox_chan_id, - clk->id); + return clk->handle->ops->dvfs.get_rate(clk->handle, clk->mbox_chan_id, + clk->id); } static int acpm_clk_determine_rate(struct clk_hw *hw, @@ -89,8 +89,8 @@ static int acpm_clk_set_rate(struct clk_hw *hw, unsigned long rate, { struct acpm_clk *clk = to_acpm_clk(hw); - return clk->handle->ops.dvfs.set_rate(clk->handle, clk->mbox_chan_id, - clk->id, rate); + return clk->handle->ops->dvfs.set_rate(clk->handle, clk->mbox_chan_id, + clk->id, rate); } static const struct clk_ops acpm_clk_ops = { diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c index a2cd54ee4589..38f40fb67ea7 100644 --- a/drivers/firmware/samsung/exynos-acpm.c +++ b/drivers/firmware/samsung/exynos-acpm.c @@ -621,30 +621,26 @@ static int acpm_channels_init(struct acpm_info *acpm) return 0; } -/** - * acpm_setup_ops() - setup the operations structures. - * @acpm: pointer to the driver data. - */ -static void acpm_setup_ops(struct acpm_info *acpm) -{ - struct acpm_dvfs_ops *dvfs_ops = &acpm->handle.ops.dvfs; - struct acpm_pmic_ops *pmic_ops = &acpm->handle.ops.pmic; - - dvfs_ops->set_rate = acpm_dvfs_set_rate; - dvfs_ops->get_rate = acpm_dvfs_get_rate; - - pmic_ops->read_reg = acpm_pmic_read_reg; - pmic_ops->bulk_read = acpm_pmic_bulk_read; - pmic_ops->write_reg = acpm_pmic_write_reg; - pmic_ops->bulk_write = acpm_pmic_bulk_write; - pmic_ops->update_reg = acpm_pmic_update_reg; -} - static void acpm_clk_pdev_unregister(void *data) { platform_device_unregister(data); } +static const struct acpm_ops exynos_acpm_driver_ops = { + .dvfs = { + .set_rate = acpm_dvfs_set_rate, + .get_rate = acpm_dvfs_get_rate, + }, + + .pmic = { + .read_reg = acpm_pmic_read_reg, + .bulk_read = acpm_pmic_bulk_read, + .write_reg = acpm_pmic_write_reg, + .bulk_write = acpm_pmic_bulk_write, + .update_reg = acpm_pmic_update_reg, + }, +}; + static int acpm_probe(struct platform_device *pdev) { const struct acpm_match_data *match_data; @@ -689,7 +685,7 @@ static int acpm_probe(struct platform_device *pdev) if (ret) return dev_err_probe(dev, ret, "Failed to add mbox free action.\n"); - acpm_setup_ops(acpm); + acpm->handle.ops = &exynos_acpm_driver_ops; platform_set_drvdata(pdev, acpm); diff --git a/drivers/mfd/sec-acpm.c b/drivers/mfd/sec-acpm.c index 9e15b260b8df..3397d13d3b7f 100644 --- a/drivers/mfd/sec-acpm.c +++ b/drivers/mfd/sec-acpm.c @@ -391,7 +391,7 @@ static int sec_pmic_acpm_bus_write(void *context, const void *data, { struct sec_pmic_acpm_bus_context *ctx = context; struct acpm_handle *acpm = ctx->shared->acpm; - const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic; + const struct acpm_pmic_ops *pmic_ops = &acpm->ops->pmic; size_t val_count = count - BITS_TO_BYTES(ACPM_ADDR_BITS); const u8 *d = data; const u8 *vals = &d[BITS_TO_BYTES(ACPM_ADDR_BITS)]; @@ -411,7 +411,7 @@ static int sec_pmic_acpm_bus_read(void *context, const void *reg_buf, size_t reg { struct sec_pmic_acpm_bus_context *ctx = context; struct acpm_handle *acpm = ctx->shared->acpm; - const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic; + const struct acpm_pmic_ops *pmic_ops = &acpm->ops->pmic; const u8 *r = reg_buf; u8 reg; @@ -430,7 +430,7 @@ static int sec_pmic_acpm_bus_reg_update_bits(void *context, unsigned int reg, un { struct sec_pmic_acpm_bus_context *ctx = context; struct acpm_handle *acpm = ctx->shared->acpm; - const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic; + const struct acpm_pmic_ops *pmic_ops = &acpm->ops->pmic; return pmic_ops->update_reg(acpm, ctx->shared->acpm_chan_id, ctx->type, reg & 0xff, ctx->shared->speedy_channel, val, mask); diff --git a/include/linux/firmware/samsung/exynos-acpm-protocol.h b/include/linux/firmware/samsung/exynos-acpm-protocol.h index b206efa62be6..fbf1829b33db 100644 --- a/include/linux/firmware/samsung/exynos-acpm-protocol.h +++ b/include/linux/firmware/samsung/exynos-acpm-protocol.h @@ -42,10 +42,10 @@ struct acpm_ops { /** * struct acpm_handle - Reference to an initialized protocol instance - * @ops: + * @ops: pointer to the constant ACPM protocol operations. */ struct acpm_handle { - struct acpm_ops ops; + const struct acpm_ops *ops; }; struct device; -- 2.54.0.545.g6539524ca2-goog
