drm/msm: Small msm_gem_purge() fix

Shoot down any mmap's *first* before put_pages().  Also add a WARN_ON
that the object is locked (to make it clear that this doesn't race with
msm_gem_fault()) and remove a redundant WARN_ON (since is_purgable()
already covers that case).

Fixes: 68209390f116 ("drm/msm: shrinker support")
Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20210405174532.1441497-8-robdclark@gmail.com
Signed-off-by: Rob Clark <robdclark@chromium.org>

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 58051bc..f0cd8b9 100644 (file)
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -729,14 +729,16 @@ void msm_gem_purge(struct drm_gem_object *obj)
        struct drm_device *dev = obj->dev;
        struct msm_gem_object *msm_obj = to_msm_bo(obj);
 
+       GEM_WARN_ON(!msm_gem_is_locked(obj));
        GEM_WARN_ON(!is_purgeable(msm_obj));
-       GEM_WARN_ON(obj->import_attach);
 
        /* Get rid of any iommu mapping(s): */
        put_iova_spaces(obj, true);
 
        msm_gem_vunmap(obj);
 
+       drm_vma_node_unmap(&obj->vma_node, dev->anon_inode->i_mapping);
+
        put_pages(obj);
 
        put_iova_vmas(obj);
@@ -744,7 +746,6 @@ void msm_gem_purge(struct drm_gem_object *obj)
        msm_obj->madv = __MSM_MADV_PURGED;
        update_inactive(msm_obj);
 
-       drm_vma_node_unmap(&obj->vma_node, dev->anon_inode->i_mapping);
        drm_gem_free_mmap_offset(obj);
 
        /* Our goal here is to return as much of the memory as