drm/amdkfd: HMM migrate vram to ram

If CPU page fault happens, HMM pgmap_ops callback migrate_to_ram start
migrate memory from vram to ram in steps:

1. migrate_vma_pages get vram pages, and notify HMM to invalidate the
pages, HMM interval notifier callback evict process queues
2. Allocate system memory pages
3. Use svm copy memory to migrate data from vram to ram
4. migrate_vma_pages copy pages structure from vram pages to ram pages
5. Return VM_FAULT_SIGBUS if migration failed, to notify application
6. migrate_vma_finalize put vram pages, page_free callback free vram
pages and vram nodes
7. Restore work wait for migration is finished, then update GPU page
table mapping to system memory, and resume process queues

Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
index 34214a44b099..37cfa1689c4f 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
@@ -142,11 +142,21 @@ void svm_range_list_fini(struct kfd_process *p);
 int svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
 	      uint64_t size, uint32_t nattrs,
 	      struct kfd_ioctl_svm_attribute *attrs);
+struct svm_range *svm_range_from_addr(struct svm_range_list *svms,
+				      unsigned long addr,
+				      struct svm_range **parent);
 struct amdgpu_device *svm_range_get_adev_by_id(struct svm_range *prange,
 					       uint32_t id);
 int svm_range_vram_node_new(struct amdgpu_device *adev,
 			    struct svm_range *prange, bool clear);
 void svm_range_vram_node_free(struct svm_range *prange);
+int svm_range_split_by_granularity(struct kfd_process *p, struct mm_struct *mm,
+			       unsigned long addr, struct svm_range *parent,
+			       struct svm_range *prange);
+void svm_range_add_list_work(struct svm_range_list *svms,
+			     struct svm_range *prange, struct mm_struct *mm,
+			     enum svm_work_list_ops op);
+void schedule_deferred_list_work(struct svm_range_list *svms);
 void svm_range_dma_unmap(struct device *dev, dma_addr_t *dma_addr,
 			 unsigned long offset, unsigned long npages);
 void svm_range_free_dma_mappings(struct svm_range *prange);