From: Dmitry Osipenko <digetx@gmail.com>
Date: Fri, 4 May 2018 02:47:19 +0300
Subject: drm/tegra: dc: Balance IOMMU group refcounting
Git-commit: 6f75b16b2683eb7c86ce2c8d150bf3fa759103b9
Patch-mainline: v4.18-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166
Remove unneeded iommu_group_get() and add missing iommu_group_put(),
correcting IOMMU group refcount. This is a minor correction / cleanup that
doesn't really fix anything because Tegra's IOMMU driver are built-in and
hence groups refcounting can't hold IOMMU driver from unloading.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/gpu/drm/tegra/dc.c | 31 +++++++++++++++----------------
drivers/gpu/drm/tegra/dc.h | 2 +-
2 files changed, 16 insertions(+), 17 deletions(-)
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -1826,7 +1826,6 @@ static irqreturn_t tegra_dc_irq(int irq,
static int tegra_dc_init(struct host1x_client *client)
{
struct drm_device *drm = dev_get_drvdata(client->parent);
- struct iommu_group *group = iommu_group_get(client->dev);
unsigned long flags = HOST1X_SYNCPT_CLIENT_MANAGED;
struct tegra_dc *dc = host1x_client_to_dc(client);
struct tegra_drm *tegra = drm->dev_private;
@@ -1838,20 +1837,21 @@ static int tegra_dc_init(struct host1x_c
if (!dc->syncpt)
dev_warn(dc->dev, "failed to allocate syncpoint\n");
- if (group && tegra->domain) {
- if (group != tegra->group) {
- err = iommu_attach_group(tegra->domain, group);
+ if (tegra->domain) {
+ dc->group = iommu_group_get(client->dev);
+
+ if (dc->group && dc->group != tegra->group) {
+ err = iommu_attach_group(tegra->domain, dc->group);
if (err < 0) {
dev_err(dc->dev,
"failed to attach to domain: %d\n",
err);
+ iommu_group_put(dc->group);
return err;
}
- tegra->group = group;
+ tegra->group = dc->group;
}
-
- dc->domain = tegra->domain;
}
if (dc->soc->wgrps)
@@ -1916,13 +1916,13 @@ cleanup:
if (!IS_ERR(primary))
drm_plane_cleanup(primary);
- if (group && dc->domain) {
- if (group == tegra->group) {
- iommu_detach_group(dc->domain, group);
+ if (dc->group) {
+ if (dc->group == tegra->group) {
+ iommu_detach_group(tegra->domain, dc->group);
tegra->group = NULL;
}
- dc->domain = NULL;
+ iommu_group_put(dc->group);
}
return err;
@@ -1931,7 +1931,6 @@ cleanup:
static int tegra_dc_exit(struct host1x_client *client)
{
struct drm_device *drm = dev_get_drvdata(client->parent);
- struct iommu_group *group = iommu_group_get(client->dev);
struct tegra_dc *dc = host1x_client_to_dc(client);
struct tegra_drm *tegra = drm->dev_private;
int err;
@@ -1944,13 +1943,13 @@ static int tegra_dc_exit(struct host1x_c
return err;
}
- if (group && dc->domain) {
- if (group == tegra->group) {
- iommu_detach_group(dc->domain, group);
+ if (dc->group) {
+ if (dc->group == tegra->group) {
+ iommu_detach_group(tegra->domain, dc->group);
tegra->group = NULL;
}
- dc->domain = NULL;
+ iommu_group_put(dc->group);
}
host1x_syncpt_free(dc->syncpt);
--- a/drivers/gpu/drm/tegra/dc.h
+++ b/drivers/gpu/drm/tegra/dc.h
@@ -92,7 +92,7 @@ struct tegra_dc {
const struct tegra_dc_soc_info *soc;
- struct iommu_domain *domain;
+ struct iommu_group *group;
};
static inline struct tegra_dc *