Nouveau - Feb 2021 - [PATCH 0/3] drm/ttm: constify static vm_operations_structs

Constify a few static vm_operations_struct that are never modified. Their
only usage is to assign their address to the vm_ops field in the
vm_area_struct, which is a pointer to const vm_operations_struct. Make them
const to allow the compiler to put them in read-only memory.

With this series applied, all static struct vm_operations_struct in the
kernel tree are const.

Rikard Falkeborn (3):
  drm/amdgpu/ttm: constify static vm_operations_struct
  drm/radeon/ttm: constify static vm_operations_struct
  drm/nouveau/ttm: constify static vm_operations_struct

 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c   | 2 +-
 drivers/gpu/drm/radeon/radeon_ttm.c     | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

-- 
2.30.0

The only usage of amdgpu_ttm_vm_ops is to assign its address to the
vm_ops field in the vm_area_struct struct. Make it const to allow the
compiler to put it in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn at gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 29cfb0809634..a785acc09f20 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -2002,7 +2002,7 @@ static vm_fault_t amdgpu_ttm_fault(struct vm_fault *vmf)
 	return ret;
 }
 
-static struct vm_operations_struct amdgpu_ttm_vm_ops = {
+static const struct vm_operations_struct amdgpu_ttm_vm_ops = {
 	.fault = amdgpu_ttm_fault,
 	.open = ttm_bo_vm_open,
 	.close = ttm_bo_vm_close,
-- 
2.30.0

The only usage of radeon_ttm_vm_ops is to assign its address to the
vm_ops field in the vm_area_struct struct. Make it const to allow the
compiler to put it in read-only memory

Signed-off-by: Rikard Falkeborn <rikard.falkeborn at gmail.com>
---
 drivers/gpu/drm/radeon/radeon_ttm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c
b/drivers/gpu/drm/radeon/radeon_ttm.c
index c45e919e03c5..5fc8bae401af 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -835,7 +835,7 @@ static vm_fault_t radeon_ttm_fault(struct vm_fault *vmf)
 	return ret;
 }
 
-static struct vm_operations_struct radeon_ttm_vm_ops = {
+static const struct vm_operations_struct radeon_ttm_vm_ops = {
 	.fault = radeon_ttm_fault,
 	.open = ttm_bo_vm_open,
 	.close = ttm_bo_vm_close,
-- 
2.30.0

The only usage of nouveau_ttm_vm_ops is to assign its address to the
vm_ops field in the vm_area_struct struct. Make it const to allow the
compiler to put it in read-only memory

Signed-off-by: Rikard Falkeborn <rikard.falkeborn at gmail.com>
---
 drivers/gpu/drm/nouveau/nouveau_ttm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_ttm.c
b/drivers/gpu/drm/nouveau/nouveau_ttm.c
index 495288182c2d..b81ae90b8449 100644
--- a/drivers/gpu/drm/nouveau/nouveau_ttm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_ttm.c
@@ -154,7 +154,7 @@ static vm_fault_t nouveau_ttm_fault(struct vm_fault *vmf)
 	return ret;
 }
 
-static struct vm_operations_struct nouveau_ttm_vm_ops = {
+static const struct vm_operations_struct nouveau_ttm_vm_ops = {
 	.fault = nouveau_ttm_fault,
 	.open = ttm_bo_vm_open,
 	.close = ttm_bo_vm_close,
-- 
2.30.0

Reviewed-by: Christian K?nig <christian.koenig at amd.com> for the series.

Am 10.02.21 um 00:48 schrieb Rikard Falkeborn:
> Constify a few static vm_operations_struct that are never modified. Their
> only usage is to assign their address to the vm_ops field in the
> vm_area_struct, which is a pointer to const vm_operations_struct. Make them
> const to allow the compiler to put them in read-only memory.
>
> With this series applied, all static struct vm_operations_struct in the
> kernel tree are const.
>
> Rikard Falkeborn (3):
>    drm/amdgpu/ttm: constify static vm_operations_struct
>    drm/radeon/ttm: constify static vm_operations_struct
>    drm/nouveau/ttm: constify static vm_operations_struct
>
>   drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 2 +-
>   drivers/gpu/drm/nouveau/nouveau_ttm.c   | 2 +-
>   drivers/gpu/drm/radeon/radeon_ttm.c     | 2 +-
>   3 files changed, 3 insertions(+), 3 deletions(-)
>