[PATCH] drm/i915: Fix 32-bit build

From: Guenter Roeck
Date: Sun Jul 17 2022 - 12:20:54 EST


Commit aff1e0b09b54 ("drm/i915/ttm: fix sg_table construction") introduces
an additional parameter to i915_rsgt_from_mm_node(). The parameter is used
to calculate segment_pages. This in turn is used in DIV_ROUND_UP() as
divisor. So far segment_pages was a constant and handled without divide
operation. Since it is no longer constant, a divide operation is now
necessary. This results in build errors on 32-bit builds.

x86_64-linux-ld: drivers/gpu/drm/i915/i915_scatterlist.o:
in function `i915_rsgt_from_mm_node':
i915_scatterlist.c:(.text+0x196): undefined reference to `__udivdi3'

Fix the problem by using DIV_ROUND_UP_ULL() instead of DIV_ROUND_UP().

Fixes: aff1e0b09b54 ("drm/i915/ttm: fix sg_table construction")
Cc: Matthew Auld <matthew.auld@xxxxxxxxx>
Cc: Nirmoy Das <nirmoy.das@xxxxxxxxx>
Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
I took a stab at the problem. Please ignore the noise if it has already
been fixed with a different patch.

drivers/gpu/drm/i915/i915_scatterlist.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_scatterlist.c b/drivers/gpu/drm/i915/i915_scatterlist.c
index f63b50b71e10..b81d5658c222 100644
--- a/drivers/gpu/drm/i915/i915_scatterlist.c
+++ b/drivers/gpu/drm/i915/i915_scatterlist.c
@@ -96,7 +96,7 @@ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node,

i915_refct_sgt_init(rsgt, node->size << PAGE_SHIFT);
st = &rsgt->table;
- if (sg_alloc_table(st, DIV_ROUND_UP(node->size, segment_pages),
+ if (sg_alloc_table(st, DIV_ROUND_UP_ULL(node->size, segment_pages),
GFP_KERNEL)) {
i915_refct_sgt_put(rsgt);
return ERR_PTR(-ENOMEM);
--
2.36.2