From 185c1ca5f1839c743f529a367211c98ad78f3545 Mon Sep 17 00:00:00 2001
From: Matthew Auld <matthew.auld@intel.com>
Date: Mon, 27 Sep 2021 12:41:03 +0100
Subject: drm/ttm: stop setting page->index for the ttm_tt
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Git-commit: 635138f72e80849db3cc39549a462bafbecc896a
Patch-mainline: v5.16-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
In commit:
commit 58aa6622d32af7d2c08d45085f44c54554a16ed7
Author: Thomas Hellstrom <thellstrom@vmware.com>
Date: Fri Jan 3 11:47:23 2014 +0100
drm/ttm: Correctly set page mapping and -index members
we started setting the page->mapping and page->index to point to the
virtual address space, if the pages were faulted with TTM. Apparently
this was needed for core-mm to able to reverse lookup the virtual
address given the struct page, and potentially unmap it from the page
tables. However as pointed out by Thomas, since we are now using
PFN_MAP, instead of say PFN_MIXED, this should no longer be the case.
There was also apparently some usecase in vmwgfx which needed this for
dirty tracking, but that also doesn't appear to be the case anymore, as
pointed out by Thomas.
We still need keep the page->mapping for now, since that is still needed
for different reasons, but we try to address that in the next patch.
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/20210927114114.152310-2-matthew.auld@intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/ttm/ttm_bo_vm.c | 2 --
drivers/gpu/drm/ttm/ttm_tt.c | 4 +---
2 files changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index 5b9b7fd01a69..9a2119fe4bdd 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -346,8 +346,6 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
} else if (unlikely(!page)) {
break;
}
- page->index = drm_vma_node_start(&bo->base.vma_node) +
- page_offset;
pfn = page_to_pfn(page);
}
diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index dae52433beeb..1cc04c224988 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -367,10 +367,8 @@ static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
if (ttm->page_flags & TTM_PAGE_FLAG_SG)
return;
- for (i = 0; i < ttm->num_pages; ++i) {
+ for (i = 0; i < ttm->num_pages; ++i)
(*page)->mapping = NULL;
- (*page++)->index = 0;
- }
}
void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
--
2.38.1