drm/ttm: move ttm_tt_{add, clear}_mapping into amdgpu

Now that setting page->index shouldn't be needed anymore, we are just
left with setting page->mapping, and here it looks like amdgpu is the
only user, where pointing the page->mapping at the dev_mapping is used
to verify that the pages do indeed belong to the device, if userspace
later tries to touch them.

v2(Christian):
  - Drop the functions altogether and just inline modifying
    the page->mapping

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210927114114.152310-3-matthew.auld@intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 1129e17..60b12bb 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1119,6 +1119,8 @@ static int amdgpu_ttm_tt_populate(struct ttm_device *bdev,
 {
        struct amdgpu_device *adev = amdgpu_ttm_adev(bdev);
        struct amdgpu_ttm_tt *gtt = (void *)ttm;
+       pgoff_t i;
+       int ret;
 
        /* user pages are bound by amdgpu_ttm_tt_pin_userptr() */
        if (gtt->userptr) {
@@ -1131,7 +1133,14 @@ static int amdgpu_ttm_tt_populate(struct ttm_device *bdev,
        if (ttm->page_flags & TTM_PAGE_FLAG_SG)
                return 0;
 
-       return ttm_pool_alloc(&adev->mman.bdev.pool, ttm, ctx);
+       ret = ttm_pool_alloc(&adev->mman.bdev.pool, ttm, ctx);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < ttm->num_pages; ++i)
+               ttm->pages[i]->mapping = bdev->dev_mapping;
+
+       return 0;
 }
 
 /*
@@ -1145,6 +1154,7 @@ static void amdgpu_ttm_tt_unpopulate(struct ttm_device *bdev,
 {
        struct amdgpu_ttm_tt *gtt = (void *)ttm;
        struct amdgpu_device *adev;
+       pgoff_t i;
 
        amdgpu_ttm_backend_unbind(bdev, ttm);
 
@@ -1158,6 +1168,9 @@ static void amdgpu_ttm_tt_unpopulate(struct ttm_device *bdev,
        if (ttm->page_flags & TTM_PAGE_FLAG_SG)
                return;
 
+       for (i = 0; i < ttm->num_pages; ++i)
+               ttm->pages[i]->mapping = NULL;
+
        adev = amdgpu_ttm_adev(bdev);
        return ttm_pool_free(&adev->mman.bdev.pool, ttm);
 }

diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index 1cc04c2..980ecb0 100644 (file)
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -289,17 +289,6 @@ out_err:
        return ret;
 }
 
-static void ttm_tt_add_mapping(struct ttm_device *bdev, struct ttm_tt *ttm)
-{
-       pgoff_t i;
-
-       if (ttm->page_flags & TTM_PAGE_FLAG_SG)
-               return;
-
-       for (i = 0; i < ttm->num_pages; ++i)
-               ttm->pages[i]->mapping = bdev->dev_mapping;
-}
-
 int ttm_tt_populate(struct ttm_device *bdev,
                    struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
 {
@@ -336,7 +325,6 @@ int ttm_tt_populate(struct ttm_device *bdev,
        if (ret)
                goto error;
 
-       ttm_tt_add_mapping(bdev, ttm);
        ttm->page_flags |= TTM_PAGE_FLAG_PRIV_POPULATED;
        if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
                ret = ttm_tt_swapin(ttm);
@@ -359,24 +347,11 @@ error:
 }
 EXPORT_SYMBOL(ttm_tt_populate);
 
-static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
-{
-       pgoff_t i;
-       struct page **page = ttm->pages;
-
-       if (ttm->page_flags & TTM_PAGE_FLAG_SG)
-               return;
-
-       for (i = 0; i < ttm->num_pages; ++i)
-               (*page)->mapping = NULL;
-}
-
 void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
 {
        if (!ttm_tt_is_populated(ttm))
                return;
 
-       ttm_tt_clear_mapping(ttm);
        if (bdev->funcs->ttm_tt_unpopulate)
                bdev->funcs->ttm_tt_unpopulate(bdev, ttm);
        else