drm/i915/gem: Suppress oom warning in favour of ENOMEM to userspace

We report object allocation failures to userspace with ENOMEM
so add __GFP_NOWARN to remove superfluous oom warnings.

Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/4936
Cc: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240626143318.11600-1-nirmoy.das@intel.com

drivers/gpu/drm/i915/i915_scatterlist.c

@@ -90,7 +90,7 @@ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node,
 
 	GEM_BUG_ON(!max_segment);
 
-	rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL);
+	rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL | __GFP_NOWARN);
 	if (!rsgt)
 		return ERR_PTR(-ENOMEM);
 
@@ -104,7 +104,7 @@ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node,
 	}
 
 	if (sg_alloc_table(st, DIV_ROUND_UP_ULL(node->size, segment_pages),
-			   GFP_KERNEL)) {
+			   GFP_KERNEL | __GFP_NOWARN)) {
 		i915_refct_sgt_put(rsgt);
 		return ERR_PTR(-ENOMEM);
 	}
@@ -178,7 +178,7 @@ struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res,
 	GEM_BUG_ON(list_empty(blocks));
 	GEM_BUG_ON(!max_segment);
 
-	rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL);
+	rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL | __GFP_NOWARN);
 	if (!rsgt)
 		return ERR_PTR(-ENOMEM);
 
@@ -190,7 +190,7 @@ struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res,
 		return ERR_PTR(-E2BIG);
 	}
 
-	if (sg_alloc_table(st, PFN_UP(res->size), GFP_KERNEL)) {
+	if (sg_alloc_table(st, PFN_UP(res->size), GFP_KERNEL | __GFP_NOWARN)) {
 		i915_refct_sgt_put(rsgt);
 		return ERR_PTR(-ENOMEM);
 	}