drm/msm: Count how many times iova memory is pinned

Add a reference count to track how many times a particular
chunk of iova memory is pinned (mapped) in the iomu and
add msm_gem_unpin_iova to give up references.

It is important to note that msm_gem_unpin_iova replaces
msm_gem_put_iova because the new implicit behavior
that an assigned iova in a given vma is now valid for the
life of the buffer and what we are really focusing on is
the use of that iova.

For now the unmappings are lazy; once the reference counts
go to zero they *COULD* be unmapped dynamically but that
will require an outside force such as a shrinker or
mm_notifiers.  For now, we're just focusing on getting
the counting right and setting ourselves up to be ready
for the future.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

3 files changed, 3 insertions, 3 deletions

diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_crtc.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_crtc.c
index ef6884f1fc34..8f2359dc87b4 100644
--- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_crtc.c
+++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_crtc.c
@@ -128,7 +128,7 @@ static void unref_cursor_worker(struct drm_flip_work *work, void *val)
 	struct mdp4_kms *mdp4_kms = get_kms(&mdp4_crtc->base);
 	struct msm_kms *kms = &mdp4_kms->base.base;
 
-	msm_gem_put_iova(val, kms->aspace);
+	msm_gem_unpin_iova(val, kms->aspace);
 	drm_gem_object_put_unlocked(val);
 }
 
diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
index 9fd6b9b2dbcb..934a49818ea4 100644
--- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
+++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
@@ -165,7 +165,7 @@ static void mdp4_destroy(struct msm_kms *kms)
 	struct msm_gem_address_space *aspace = kms->aspace;
 
 	if (mdp4_kms->blank_cursor_iova)
-		msm_gem_put_iova(mdp4_kms->blank_cursor_bo, kms->aspace);
+		msm_gem_unpin_iova(mdp4_kms->blank_cursor_bo, kms->aspace);
 	drm_gem_object_put_unlocked(mdp4_kms->blank_cursor_bo);
 
 	if (aspace) {
diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c
index c7cc276575fb..c5fde1a4191a 100644
--- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c
+++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c
@@ -173,7 +173,7 @@ static void unref_cursor_worker(struct drm_flip_work *work, void *val)
 	struct mdp5_kms *mdp5_kms = get_kms(&mdp5_crtc->base);
 	struct msm_kms *kms = &mdp5_kms->base.base;
 
-	msm_gem_put_iova(val, kms->aspace);
+	msm_gem_unpin_iova(val, kms->aspace);
 	drm_gem_object_put_unlocked(val);
 }