drm/amdgpu: use hmm_pfns instead of array of pages

we dont need to allocate local array of pages to hold
the pages returned by the hmm, instead we could use
the hmm_range structure itself to get to hmm_pfn
and get the required pages directly.

This avoids call to alloc/free quite a lot.

Signed-off-by: Sunil Khatri <sunil.khatri@amd.com>
Suggested-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Acked-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 6 insertions, 24 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index defb511acc5a..744e6ff69814 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -29,6 +29,7 @@
 #include <linux/pagemap.h>
 #include <linux/sync_file.h>
 #include <linux/dma-buf.h>
+#include <linux/hmm.h>
 
 #include <drm/amdgpu_drm.h>
 #include <drm/drm_syncobj.h>
@@ -885,24 +886,12 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 		struct amdgpu_bo *bo = e->bo;
 		int i;
 
-		e->user_pages = kvcalloc(bo->tbo.ttm->num_pages,
-					 sizeof(struct page *),
-					 GFP_KERNEL);
-		if (!e->user_pages) {
-			drm_err(adev_to_drm(p->adev), "kvmalloc_array failure\n");
-			r = -ENOMEM;
-			goto out_free_user_pages;
-		}
-
-		r = amdgpu_ttm_tt_get_user_pages(bo, e->user_pages, &e->range);
-		if (r) {
-			kvfree(e->user_pages);
-			e->user_pages = NULL;
+		r = amdgpu_ttm_tt_get_user_pages(bo, &e->range);
+		if (r)
 			goto out_free_user_pages;
-		}
 
 		for (i = 0; i < bo->tbo.ttm->num_pages; i++) {
-			if (bo->tbo.ttm->pages[i] != e->user_pages[i]) {
+			if (bo->tbo.ttm->pages[i] != hmm_pfn_to_page(e->range->hmm_pfns[i])) {
 				userpage_invalidated = true;
 				break;
 			}
@@ -946,7 +935,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 		}
 
 		if (amdgpu_ttm_tt_is_userptr(e->bo->tbo.ttm) &&
-		    e->user_invalidated && e->user_pages) {
+		    e->user_invalidated) {
 			amdgpu_bo_placement_from_domain(e->bo,
 							AMDGPU_GEM_DOMAIN_CPU);
 			r = ttm_bo_validate(&e->bo->tbo, &e->bo->placement,
@@ -955,11 +944,8 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 				goto out_free_user_pages;
 
 			amdgpu_ttm_tt_set_user_pages(e->bo->tbo.ttm,
-						     e->user_pages);
+						     e->range);
 		}
-
-		kvfree(e->user_pages);
-		e->user_pages = NULL;
 	}
 
 	amdgpu_cs_get_threshold_for_moves(p->adev, &p->bytes_moved_threshold,
@@ -1001,11 +987,7 @@ out_free_user_pages:
 	amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
 		struct amdgpu_bo *bo = e->bo;
 
-		if (!e->user_pages)
-			continue;
 		amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm, e->range);
-		kvfree(e->user_pages);
-		e->user_pages = NULL;
 		e->range = NULL;
 	}
 	mutex_unlock(&p->bo_list->bo_list_mutex);