[PATCH v2 3/3] drm/xe: Use ttm_bo_access in xe_vm_snapshot_capture_delayed

[Matthew Brost <matthew.brost@xxxxxxxxx>]

Non-contiguous mapping of BO in VRAM doesn't work, use ttm_bo_access
instead.

v2:
 - Fix error handling

Fixes: 0eb2a18a8fad ("drm/xe: Implement VM snapshot support for BO's and userptr")
Suggested-by: Matthew Auld <matthew.auld@xxxxxxxxx>
Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
---
 drivers/gpu/drm/xe/xe_vm.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index c99380271de6..0f760fd69d44 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -3303,7 +3303,6 @@ void xe_vm_snapshot_capture_delayed(struct xe_vm_snapshot *snap)
 
 	for (int i = 0; i < snap->num_snaps; i++) {
 		struct xe_bo *bo = snap->snap[i].bo;
-		struct iosys_map src;
 		int err;
 
 		if (IS_ERR(snap->snap[i].data))
@@ -3316,16 +3315,12 @@ void xe_vm_snapshot_capture_delayed(struct xe_vm_snapshot *snap)
 		}
 
 		if (bo) {
-			xe_bo_lock(bo, false);
-			err = ttm_bo_vmap(&bo->ttm, &src);
-			if (!err) {
-				xe_map_memcpy_from(xe_bo_device(bo),
-						   snap->snap[i].data,
-						   &src, snap->snap[i].bo_ofs,
-						   snap->snap[i].len);
-				ttm_bo_vunmap(&bo->ttm, &src);
-			}
-			xe_bo_unlock(bo);
+			err = ttm_bo_access(&bo->ttm, snap->snap[i].bo_ofs,
+					    snap->snap[i].data, snap->snap[i].len, 0);
+			if (!(err < 0) && err != snap->snap[i].len)
+				err = -EIO;
+			else if (!(err < 0))
+				err = 0;
 		} else {
 			void __user *userptr = (void __user *)(size_t)snap->snap[i].bo_ofs;
 
@@ -3375,6 +3370,7 @@ void xe_vm_snapshot_print(struct xe_vm_snapshot *snap, struct drm_printer *p)
 			u32 *val = snap->snap[i].data + j;
 			char dumped[ASCII85_BUFSZ];
 
+			printk("%s:%d: j=%d", __func__, __LINE__, (int)j);
 			drm_puts(p, ascii85_encode(*val, dumped));
 		}
 
-- 
2.34.1