[Intel-xe] [PATCH] xe/xe_bo: Reject bo creation of unaligned size

[Zbigniew Kempczyński]

From: Mauro Carvalho Chehab <mauro.chehab at linux.intel.com>

For xe bo creation we request passing size which matches system or
vram minimum page alignment. This way we want to ensure userspace
is aware of region constraints and not aligned allocations will be
rejected returning EINVAL.

Signed-off-by: Mauro Carvalho Chehab <mauro.chehab at linux.intel.com>
Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski at intel.com>
---
 drivers/gpu/drm/xe/xe_bo.c | 23 ++++++++++++++++-------
 include/uapi/drm/xe_drm.h  |  5 ++---
 2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
index 3ab404e33fae..d3972c84bcce 100644
--- a/drivers/gpu/drm/xe/xe_bo.c
+++ b/drivers/gpu/drm/xe/xe_bo.c
@@ -1090,6 +1090,7 @@ struct xe_bo *__xe_bo_create_locked(struct xe_device *xe, struct xe_bo *bo,
 	};
 	struct ttm_placement *placement;
 	uint32_t alignment;
+	size_t aligned_size;
 	int err;
 
 	/* Only kernel objects should set GT */
@@ -1098,22 +1099,30 @@ struct xe_bo *__xe_bo_create_locked(struct xe_device *xe, struct xe_bo *bo,
 	if (XE_WARN_ON(!size))
 		return ERR_PTR(-EINVAL);
 
-	if (!bo) {
-		bo = xe_bo_alloc();
-		if (IS_ERR(bo))
-			return bo;
-	}
-
 	if (flags & (XE_BO_CREATE_VRAM_MASK | XE_BO_CREATE_STOLEN_BIT) &&
 	    !(flags & XE_BO_CREATE_IGNORE_MIN_PAGE_SIZE_BIT) &&
 	    xe->info.vram_flags & XE_VRAM_FLAGS_NEED64K) {
-		size = ALIGN(size, SZ_64K);
+		aligned_size = ALIGN(size, SZ_64K);
+		if (type != ttm_bo_type_device)
+			size = ALIGN(size, SZ_64K);
 		flags |= XE_BO_INTERNAL_64K;
 		alignment = SZ_64K >> PAGE_SHIFT;
+
 	} else {
+		aligned_size = ALIGN(size, SZ_4K);
+		flags &= ~XE_BO_INTERNAL_64K;
 		alignment = SZ_4K >> PAGE_SHIFT;
 	}
 
+	if (type == ttm_bo_type_device && aligned_size != size)
+		return ERR_PTR(-EINVAL);
+
+	if (!bo) {
+		bo = xe_bo_alloc();
+		if (IS_ERR(bo))
+			return bo;
+	}
+
 	bo->gt = gt;
 	bo->size = size;
 	bo->flags = flags;
diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index b0b80aae3ee8..d3e64af7eabb 100644
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -259,9 +259,8 @@ struct drm_xe_gem_create {
 	__u64 extensions;
 
 	/**
-	 * @size: Requested size for the object
-	 *
-	 * The (page-aligned) allocated size for the object will be returned.
+	 * @size: Size of the object to be created, must match region
+	 * (system or vram) minimum alignment.
 	 */
 	__u64 size;
 
-- 
2.34.1