[PATCH] drm/amdgpu: fix building without CONFIG_HMM_MIRROR

From: Arnd Bergmann
Date: Mon Jul 08 2019 - 09:51:47 EST

'struct hmm_mirror' is not defined without the Kconfig option set,
so we cannot include it within another struct:

In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:72:
drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mn.h:69:20: error: field has incomplete type 'struct hmm_mirror'
struct hmm_mirror mirror;
drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mn.h:69:9: note: forward declaration of 'struct hmm_mirror'
struct hmm_mirror mirror;

Add the #ifdef around it that is also used for all functions operating
on it.

Fixes: 7590f6d211ec ("drm/amdgpu: Prepare for hmm_range_register API change")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
index 281fd9fef662..b8ed68943625 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
@@ -65,8 +65,10 @@ struct amdgpu_mn {
struct rw_semaphore lock;
struct rb_root_cached objects;

/* HMM mirror */
struct hmm_mirror mirror;

#if defined(CONFIG_HMM_MIRROR)