drm/amd/display: use kvmalloc for dc_state (v2)

It's large and doesn't need contiguous memory.  Fixes
allocation failures in some cases.

v2: kvfree the memory.
Reviewed-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -23,6 +23,7 @@
  */
 
 #include <linux/slab.h>
+#include <linux/mm.h>
 
 #include "dm_services.h"
 
@@ -1171,8 +1172,8 @@ bool dc_post_update_surfaces_to_stream(struct dc *dc)
 
 struct dc_state *dc_create_state(struct dc *dc)
 {
-	struct dc_state *context = kzalloc(sizeof(struct dc_state),
-					   GFP_KERNEL);
+	struct dc_state *context = kvzalloc(sizeof(struct dc_state),
+					    GFP_KERNEL);
 
 	if (!context)
 		return NULL;
@@ -1192,11 +1193,11 @@ struct dc_state *dc_create_state(struct dc *dc)
 struct dc_state *dc_copy_state(struct dc_state *src_ctx)
 {
 	int i, j;
-	struct dc_state *new_ctx = kmemdup(src_ctx,
-			sizeof(struct dc_state), GFP_KERNEL);
+	struct dc_state *new_ctx = kvmalloc(sizeof(struct dc_state), GFP_KERNEL);
 
 	if (!new_ctx)
 		return NULL;
+	memcpy(new_ctx, src_ctx, sizeof(struct dc_state));
 
 	for (i = 0; i < MAX_PIPES; i++) {
 			struct pipe_ctx *cur_pipe = &new_ctx->res_ctx.pipe_ctx[i];
@@ -1230,7 +1231,7 @@ static void dc_state_free(struct kref *kref)
 {
 	struct dc_state *context = container_of(kref, struct dc_state, refcount);
 	dc_resource_state_destruct(context);
-	kfree(context);
+	kvfree(context);
 }
 
 void dc_release_state(struct dc_state *context)