[Intel-xe] [PATCH] drm/xe: Fix splat during error dump

[Francois Dugast]

Allow xe_bo_addr without lock to print debug information, such
as from xe_analyze_vm.

Signed-off-by: Francois Dugast <francois.dugast at intel.com>
---
 drivers/gpu/drm/xe/xe_bo.c | 19 +++++++++++++++----
 drivers/gpu/drm/xe/xe_bo.h |  2 ++
 drivers/gpu/drm/xe/xe_vm.c |  2 +-
 3 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
index 3ab404e33fae..c82e995df779 100644
--- a/drivers/gpu/drm/xe/xe_bo.c
+++ b/drivers/gpu/drm/xe/xe_bo.c
@@ -1545,15 +1545,18 @@ bool xe_bo_is_xe_bo(struct ttm_buffer_object *bo)
 	return false;
 }
 
-dma_addr_t xe_bo_addr(struct xe_bo *bo, u64 offset,
+/*
+ * Resolve a BO address. There is no assert to check if the proper lock is held
+ * so it should only be used in cases where it is not fatal to get the wrong
+ * address, such as printing debug information, but not in cases where memory is
+ * written based on this result.
+ */
+dma_addr_t __xe_bo_addr(struct xe_bo *bo, u64 offset,
 		      size_t page_size, bool *is_vram)
 {
 	struct xe_res_cursor cur;
 	u64 page;
 
-	if (!READ_ONCE(bo->ttm.pin_count))
-		xe_bo_assert_held(bo);
-
 	XE_BUG_ON(page_size > PAGE_SIZE);
 	page = offset >> PAGE_SHIFT;
 	offset &= (PAGE_SIZE - 1);
@@ -1575,6 +1578,14 @@ dma_addr_t xe_bo_addr(struct xe_bo *bo, u64 offset,
 	}
 }
 
+dma_addr_t xe_bo_addr(struct xe_bo *bo, u64 offset,
+		      size_t page_size, bool *is_vram)
+{
+	if (!READ_ONCE(bo->ttm.pin_count))
+		xe_bo_assert_held(bo);
+	return __xe_bo_addr(bo, offset, page_size, is_vram);
+}
+
 int xe_bo_vmap(struct xe_bo *bo)
 {
 	void *virtual;
diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h
index 8354d05ccdf3..7e111332c35a 100644
--- a/drivers/gpu/drm/xe/xe_bo.h
+++ b/drivers/gpu/drm/xe/xe_bo.h
@@ -199,6 +199,8 @@ static inline void xe_bo_unpin_map_no_vm(struct xe_bo *bo)
 }
 
 bool xe_bo_is_xe_bo(struct ttm_buffer_object *bo);
+dma_addr_t __xe_bo_addr(struct xe_bo *bo, u64 offset,
+		      size_t page_size, bool *is_vram);
 dma_addr_t xe_bo_addr(struct xe_bo *bo, u64 offset,
 		      size_t page_size, bool *is_vram);
 
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index 272f0f7f24fe..91576cec000d 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -3397,7 +3397,7 @@ int xe_analyze_vm(struct drm_printer *p, struct xe_vm *vm, int gt_id)
 					&cur);
 			addr = xe_res_dma(&cur);
 		} else {
-			addr = xe_bo_addr(vma->bo, 0, XE_PAGE_SIZE, &is_vram);
+			addr = __xe_bo_addr(vma->bo, 0, XE_PAGE_SIZE, &is_vram);
 		}
 		drm_printf(p, " [%016llx-%016llx] S:0x%016llx A:%016llx %s\n",
 			   vma->start, vma->end, vma->end - vma->start + 1ull,
-- 
2.25.1