2022-10-20 08:52:07

by Deming Wang

Subject: [PATCH] drm/amdkfd: use vma_lookup() instead of find_vma()

Using vma_lookup() verifies the start address is contained in the found
vma. This results in easier to read the code.

Signed-off-by: Deming Wang <[email protected]>
---
drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index 64fdf63093a0..0100812478b2 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -1586,8 +1586,8 @@ static int svm_range_validate_and_map(struct mm_struct *mm,
unsigned long npages;
bool readonly;

- vma = find_vma(mm, addr);
- if (!vma || addr < vma->vm_start) {
+ vma = vma_lookup(mm, addr);
+ if (!vma) {
r = -EFAULT;
goto unreserve_out;
}
@@ -2542,8 +2542,8 @@ svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
struct interval_tree_node *node;
unsigned long start_limit, end_limit;

- vma = find_vma(p->mm, addr << PAGE_SHIFT);
- if (!vma || (addr << PAGE_SHIFT) < vma->vm_start) {
+ vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
+ if (!vma) {
pr_debug("VMA does not exist in address [0x%llx]\n", addr);
return -EFAULT;
}
@@ -2871,8 +2871,8 @@ svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
/* __do_munmap removed VMA, return success as we are handling stale
* retry fault.
*/
- vma = find_vma(mm, addr << PAGE_SHIFT);
- if (!vma || (addr << PAGE_SHIFT) < vma->vm_start) {
+ vma = vma_lookup(mm, addr << PAGE_SHIFT);
+ if (!vma) {
pr_debug("address 0x%llx VMA is removed\n", addr);
r = 0;
goto out_unlock_range;
@@ -3152,9 +3152,8 @@ svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
start <<= PAGE_SHIFT;
end = start + (size << PAGE_SHIFT);
do {
- vma = find_vma(p->mm, start);
- if (!vma || start < vma->vm_start ||
- (vma->vm_flags & device_vma))
+ vma = vma_lookup(p->mm, start);
+ if (!vma || (vma->vm_flags & device_vma))
return -EFAULT;
start = min(end, vma->vm_end);
} while (start < end);
--
2.27.0

2022-10-20 17:11:09

by Felix Kuehling

Subject: Re: [PATCH] drm/amdkfd: use vma_lookup() instead of find_vma()

Am 2022-10-20 um 04:20 schrieb Deming Wang:
> Using vma_lookup() verifies the start address is contained in the found
> vma. This results in easier to read the code.
>
> Signed-off-by: Deming Wang <[email protected]>

Thank you. This patch is

Reviewed-by: Felix Kuehling <[email protected]>

I squashed it with your earlier patch in kfd_migrate.c and submitted it
to our amd-staging-drm-next branch.

Regards,
  Felix


> ---
> drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 17 ++++++++---------
> 1 file changed, 8 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> index 64fdf63093a0..0100812478b2 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> @@ -1586,8 +1586,8 @@ static int svm_range_validate_and_map(struct mm_struct *mm,
> unsigned long npages;
> bool readonly;
>
> - vma = find_vma(mm, addr);
> - if (!vma || addr < vma->vm_start) {
> + vma = vma_lookup(mm, addr);
> + if (!vma) {
> r = -EFAULT;
> goto unreserve_out;
> }
> @@ -2542,8 +2542,8 @@ svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
> struct interval_tree_node *node;
> unsigned long start_limit, end_limit;
>
> - vma = find_vma(p->mm, addr << PAGE_SHIFT);
> - if (!vma || (addr << PAGE_SHIFT) < vma->vm_start) {
> + vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
> + if (!vma) {
> pr_debug("VMA does not exist in address [0x%llx]\n", addr);
> return -EFAULT;
> }
> @@ -2871,8 +2871,8 @@ svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
> /* __do_munmap removed VMA, return success as we are handling stale
> * retry fault.
> */
> - vma = find_vma(mm, addr << PAGE_SHIFT);
> - if (!vma || (addr << PAGE_SHIFT) < vma->vm_start) {
> + vma = vma_lookup(mm, addr << PAGE_SHIFT);
> + if (!vma) {
> pr_debug("address 0x%llx VMA is removed\n", addr);
> r = 0;
> goto out_unlock_range;
> @@ -3152,9 +3152,8 @@ svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
> start <<= PAGE_SHIFT;
> end = start + (size << PAGE_SHIFT);
> do {
> - vma = find_vma(p->mm, start);
> - if (!vma || start < vma->vm_start ||
> - (vma->vm_flags & device_vma))
> + vma = vma_lookup(p->mm, start);
> + if (!vma || (vma->vm_flags & device_vma))
> return -EFAULT;
> start = min(end, vma->vm_end);
> } while (start < end);