On 2026-01-07 04:18, Jordan Niethe wrote:
A future change will remove device private pages from the physical
address space. This will mean that device private pages no longer have a
pfn.
A MIGRATE_PFN flag will be introduced that distinguishes between mpfns
that contain a pfn vs an offset into device private memory.
Replace usages of pfns and page_to_pfn() to mpfns and
migrate_pfn_to_page() to prepare for handling this distinction. This
will assist in continuing to use the same code paths for both
MEMORY_DEVICE_PRIVATE and MEMORY_DEVICE_COHERENT devices.
Signed-off-by: Jordan Niethe <[email protected]>
---
v2:
- New to series
---
drivers/gpu/drm/amd/amdkfd/kfd_migrate.c | 15 +++++++--------
drivers/gpu/drm/amd/amdkfd/kfd_migrate.h | 2 +-
2 files changed, 8 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
index ca552c34ece2..c493b19268cc 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
@@ -204,17 +204,17 @@ svm_migrate_copy_done(struct amdgpu_device *adev, struct
dma_fence *mfence)
}
unsigned long
-svm_migrate_addr_to_pfn(struct amdgpu_device *adev, unsigned long addr)
+svm_migrate_addr_to_mpfn(struct amdgpu_device *adev, unsigned long addr)
{
- return (addr + adev->kfd.pgmap.range.start) >> PAGE_SHIFT;
+ return migrate_pfn((addr + adev->kfd.pgmap.range.start) >> PAGE_SHIFT);
}
static void
-svm_migrate_get_vram_page(struct svm_range *prange, unsigned long pfn)
+svm_migrate_get_vram_page(struct svm_range *prange, unsigned long mpfn)
{
struct page *page;
- page = pfn_to_page(pfn);
+ page = migrate_pfn_to_page(mpfn);
svm_range_bo_ref(prange->svm_bo);
page->zone_device_data = prange->svm_bo;
zone_device_page_init(page, 0);
@@ -225,7 +225,7 @@ svm_migrate_put_vram_page(struct amdgpu_device *adev,
unsigned long addr)
{
struct page *page;
- page = pfn_to_page(svm_migrate_addr_to_pfn(adev, addr));
+ page = migrate_pfn_to_page(svm_migrate_addr_to_mpfn(adev, addr));
unlock_page(page);
put_page(page);
}
@@ -235,7 +235,7 @@ svm_migrate_addr(struct amdgpu_device *adev, struct page
*page)
{
unsigned long addr;
- addr = page_to_pfn(page) << PAGE_SHIFT;
+ addr = (migrate_pfn_from_page(page) >> MIGRATE_PFN_SHIFT) << PAGE_SHIFT;
return (addr - adev->kfd.pgmap.range.start);
I guess we rely on the fact that for DEVICE_PRIVATE memory,
adev->kfd.pgmap.range.start will be 0 after your patch 11. So we don't
need a special condition here to handle DEVICE_PRIVATE differently.
In general, I like the way you handle mpfns as it keeps all the special
casing out of the drivers.
Regards,
Felix
}
@@ -301,9 +301,8 @@ svm_migrate_copy_to_vram(struct kfd_node *node, struct svm_range *prange,
if (migrate->src[i] & MIGRATE_PFN_MIGRATE) {
dst[i] = cursor.start + (j << PAGE_SHIFT);
- migrate->dst[i] = svm_migrate_addr_to_pfn(adev, dst[i]);
+ migrate->dst[i] = svm_migrate_addr_to_mpfn(adev,
dst[i]);
svm_migrate_get_vram_page(prange, migrate->dst[i]);
- migrate->dst[i] = migrate_pfn(migrate->dst[i]);
mpages++;
}
spage = migrate_pfn_to_page(migrate->src[i]);
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.h
b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.h
index 2b7fd442d29c..a80b72abe1e0 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.h
@@ -48,7 +48,7 @@ int svm_migrate_vram_to_ram(struct svm_range *prange, struct
mm_struct *mm,
uint32_t trigger, struct page *fault_page);
unsigned long
-svm_migrate_addr_to_pfn(struct amdgpu_device *adev, unsigned long addr);
+svm_migrate_addr_to_mpfn(struct amdgpu_device *adev, unsigned long addr);
#endif /* IS_ENABLED(CONFIG_HSA_AMD_SVM) */
