[PATCH v2 3/7] drm/xe/migrate: fix batch buffer sizing

[Matthew Auld <matthew.auld@intel.com>]

In xe_migrate_vram() the copy can straddle page boundaries, so the len
might look like a single page, but actually accounting for the offset
within the page we will need to emit more than one PTE. Otherwise in
some cases the batch buffer will be undersized leading to warnings
later.  We already have npages so use that instead.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
---
 drivers/gpu/drm/xe/xe_migrate.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index 7643715f63cc..665ab38b39f1 100644
--- a/drivers/gpu/drm/xe/xe_migrate.c
+++ b/drivers/gpu/drm/xe/xe_migrate.c
@@ -1894,7 +1894,7 @@ static struct dma_fence *xe_migrate_vram(struct xe_migrate *m,
 
 	xe_assert(xe, npages * PAGE_SIZE <= MAX_PREEMPTDISABLE_TRANSFER);
 
-	batch_size += pte_update_cmd_size(len);
+	batch_size += pte_update_cmd_size(npages << PAGE_SHIFT);
 	batch_size += EMIT_COPY_DW;
 
 	bb = xe_bb_new(gt, batch_size, use_usm_batch);
-- 
2.51.0