drm/amd/pm: Replace one-element array with flexible-array in struct phm_ppt_v1_clock_...

There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].

Refactor the code according to the use of a flexible-array member in
struct phm_ppt_v1_clock_voltage_dependency_table, instead of a one-element
array, and use the struct_size() helper to calculate the size for the
allocation.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays

Build-tested-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/5f7c433c.TTk9rnA+F58kyDUy%25lkp@intel.com/
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h
index c0193e0..c167083 100644 (file)
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h
@@ -48,7 +48,7 @@ typedef struct phm_ppt_v1_clock_voltage_dependency_record phm_ppt_v1_clock_volta
 
 struct phm_ppt_v1_clock_voltage_dependency_table {
        uint32_t count;                                            /* Number of entries. */
-       phm_ppt_v1_clock_voltage_dependency_record entries[1];     /* Dynamically allocate count entries. */
+       phm_ppt_v1_clock_voltage_dependency_record entries[];      /* Dynamically allocate count entries. */
 };
 
 typedef struct phm_ppt_v1_clock_voltage_dependency_table phm_ppt_v1_clock_voltage_dependency_table;

diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c
index 52188f6..0725531 100644 (file)
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c
@@ -367,7 +367,7 @@ static int get_mclk_voltage_dependency_table(
                ATOM_Tonga_MCLK_Dependency_Table const *mclk_dep_table
                )
 {
-       uint32_t table_size, i;
+       uint32_t i;
        phm_ppt_v1_clock_voltage_dependency_table *mclk_table;
        phm_ppt_v1_clock_voltage_dependency_record *mclk_table_record;
        ATOM_Tonga_MCLK_Dependency_Record *mclk_dep_record;
@@ -375,12 +375,9 @@ static int get_mclk_voltage_dependency_table(
        PP_ASSERT_WITH_CODE((0 != mclk_dep_table->ucNumEntries),
                "Invalid PowerPlay Table!", return -1);
 
-       table_size = sizeof(uint32_t) + sizeof(phm_ppt_v1_clock_voltage_dependency_record)
-               * mclk_dep_table->ucNumEntries;
-
-       mclk_table = kzalloc(table_size, GFP_KERNEL);
-
-       if (NULL == mclk_table)
+       mclk_table = kzalloc(struct_size(mclk_table, entries, mclk_dep_table->ucNumEntries),
+                            GFP_KERNEL);
+       if (!mclk_table)
                return -ENOMEM;
 
        mclk_table->count = (uint32_t)mclk_dep_table->ucNumEntries;
@@ -410,7 +407,7 @@ static int get_sclk_voltage_dependency_table(
                PPTable_Generic_SubTable_Header const  *sclk_dep_table
                )
 {
-       uint32_t table_size, i;
+       uint32_t i;
        phm_ppt_v1_clock_voltage_dependency_table *sclk_table;
        phm_ppt_v1_clock_voltage_dependency_record *sclk_table_record;
 
@@ -422,12 +419,9 @@ static int get_sclk_voltage_dependency_table(
                PP_ASSERT_WITH_CODE((0 != tonga_table->ucNumEntries),
                        "Invalid PowerPlay Table!", return -1);
 
-               table_size = sizeof(uint32_t) + sizeof(phm_ppt_v1_clock_voltage_dependency_record)
-                       * tonga_table->ucNumEntries;
-
-               sclk_table = kzalloc(table_size, GFP_KERNEL);
-
-               if (NULL == sclk_table)
+               sclk_table = kzalloc(struct_size(sclk_table, entries, tonga_table->ucNumEntries),
+                                    GFP_KERNEL);
+               if (!sclk_table)
                        return -ENOMEM;
 
                sclk_table->count = (uint32_t)tonga_table->ucNumEntries;
@@ -454,12 +448,9 @@ static int get_sclk_voltage_dependency_table(
                PP_ASSERT_WITH_CODE((0 != polaris_table->ucNumEntries),
                        "Invalid PowerPlay Table!", return -1);
 
-               table_size = sizeof(uint32_t) + sizeof(phm_ppt_v1_clock_voltage_dependency_record)
-                       * polaris_table->ucNumEntries;
-
-               sclk_table = kzalloc(table_size, GFP_KERNEL);
-
-               if (NULL == sclk_table)
+               sclk_table = kzalloc(struct_size(sclk_table, entries, polaris_table->ucNumEntries),
+                                    GFP_KERNEL);
+               if (!sclk_table)
                        return -ENOMEM;
 
                sclk_table->count = (uint32_t)polaris_table->ucNumEntries;

diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_processpptables.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_processpptables.c
index e655c04..787b23f 100644 (file)
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_processpptables.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_processpptables.c
@@ -571,18 +571,14 @@ static int get_socclk_voltage_dependency_table(
                phm_ppt_v1_clock_voltage_dependency_table **pp_vega10_clk_dep_table,
                const ATOM_Vega10_SOCCLK_Dependency_Table *clk_dep_table)
 {
-       uint32_t table_size, i;
+       uint32_t i;
        phm_ppt_v1_clock_voltage_dependency_table *clk_table;
 
        PP_ASSERT_WITH_CODE(clk_dep_table->ucNumEntries,
                "Invalid PowerPlay Table!", return -1);
 
-       table_size = sizeof(uint32_t) +
-                       sizeof(phm_ppt_v1_clock_voltage_dependency_record) *
-                       clk_dep_table->ucNumEntries;
-
-       clk_table = kzalloc(table_size, GFP_KERNEL);
-
+       clk_table = kzalloc(struct_size(clk_table, entries, clk_dep_table->ucNumEntries),
+                           GFP_KERNEL);
        if (!clk_table)
                return -ENOMEM;
 
@@ -605,18 +601,14 @@ static int get_mclk_voltage_dependency_table(
                phm_ppt_v1_clock_voltage_dependency_table **pp_vega10_mclk_dep_table,
                const ATOM_Vega10_MCLK_Dependency_Table *mclk_dep_table)
 {
-       uint32_t table_size, i;
+       uint32_t i;
        phm_ppt_v1_clock_voltage_dependency_table *mclk_table;
 
        PP_ASSERT_WITH_CODE(mclk_dep_table->ucNumEntries,
                "Invalid PowerPlay Table!", return -1);
 
-       table_size = sizeof(uint32_t) +
-                       sizeof(phm_ppt_v1_clock_voltage_dependency_record) *
-                       mclk_dep_table->ucNumEntries;
-
-       mclk_table = kzalloc(table_size, GFP_KERNEL);
-
+       mclk_table = kzalloc(struct_size(mclk_table, entries, mclk_dep_table->ucNumEntries),
+                           GFP_KERNEL);
        if (!mclk_table)
                return -ENOMEM;
 
@@ -644,7 +636,7 @@ static int get_gfxclk_voltage_dependency_table(
                        **pp_vega10_clk_dep_table,
                const ATOM_Vega10_GFXCLK_Dependency_Table *clk_dep_table)
 {
-       uint32_t table_size, i;
+       uint32_t i;
        struct phm_ppt_v1_clock_voltage_dependency_table
                                *clk_table;
        ATOM_Vega10_GFXCLK_Dependency_Record_V2 *patom_record_v2;
@@ -652,12 +644,8 @@ static int get_gfxclk_voltage_dependency_table(
        PP_ASSERT_WITH_CODE((clk_dep_table->ucNumEntries != 0),
                        "Invalid PowerPlay Table!", return -1);
 
-       table_size = sizeof(uint32_t) +
-                       sizeof(phm_ppt_v1_clock_voltage_dependency_record) *
-                       clk_dep_table->ucNumEntries;
-
-       clk_table = kzalloc(table_size, GFP_KERNEL);
-
+       clk_table = kzalloc(struct_size(clk_table, entries, clk_dep_table->ucNumEntries),
+                           GFP_KERNEL);
        if (!clk_table)
                return -ENOMEM;
 
@@ -711,19 +699,15 @@ static int get_pix_clk_voltage_dependency_table(
                        **pp_vega10_clk_dep_table,
                const  ATOM_Vega10_PIXCLK_Dependency_Table *clk_dep_table)
 {
-       uint32_t table_size, i;
+       uint32_t i;
        struct phm_ppt_v1_clock_voltage_dependency_table
                                *clk_table;
 
        PP_ASSERT_WITH_CODE((clk_dep_table->ucNumEntries != 0),
                        "Invalid PowerPlay Table!", return -1);
 
-       table_size = sizeof(uint32_t) +
-                       sizeof(phm_ppt_v1_clock_voltage_dependency_record) *
-                       clk_dep_table->ucNumEntries;
-
-       clk_table = kzalloc(table_size, GFP_KERNEL);
-
+       clk_table = kzalloc(struct_size(clk_table, entries, clk_dep_table->ucNumEntries),
+                           GFP_KERNEL);
        if (!clk_table)
                return -ENOMEM;
 
@@ -747,7 +731,7 @@ static int get_dcefclk_voltage_dependency_table(
                        **pp_vega10_clk_dep_table,
                const ATOM_Vega10_DCEFCLK_Dependency_Table *clk_dep_table)
 {
-       uint32_t table_size, i;
+       uint32_t i;
        uint8_t num_entries;
        struct phm_ppt_v1_clock_voltage_dependency_table
                                *clk_table;
@@ -775,12 +759,8 @@ static int get_dcefclk_voltage_dependency_table(
                num_entries = clk_dep_table->ucNumEntries;
 
 
-       table_size = sizeof(uint32_t) +
-                       sizeof(phm_ppt_v1_clock_voltage_dependency_record) *
-                       num_entries;
-
-       clk_table = kzalloc(table_size, GFP_KERNEL);
-
+       clk_table = kzalloc(struct_size(clk_table, entries, num_entries),
+                           GFP_KERNEL);
        if (!clk_table)
                return -ENOMEM;