From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: [PATCH v1 1/5] drm/tegra: dc: Balance IOMMU group refcounting Date: Fri, 4 May 2018 02:47:19 +0300 Message-ID: <20180503234723.4368-2-digetx@gmail.com> References: <20180503234723.4368-1-digetx@gmail.com> Return-path: In-Reply-To: <20180503234723.4368-1-digetx@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Thierry Reding Cc: dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-tegra@vger.kernel.org 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 --- drivers/gpu/drm/tegra/dc.c | 35 +++++++++++++++++------------------ drivers/gpu/drm/tegra/dc.h | 2 +- drivers/gpu/drm/tegra/drm.h | 2 +- 3 files changed, 19 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c index d7a0f62c6e2e..9fc34c6a7218 100644 --- a/drivers/gpu/drm/tegra/dc.c +++ b/drivers/gpu/drm/tegra/dc.c @@ -1927,7 +1927,6 @@ static irqreturn_t tegra_dc_irq(int irq, void *data) 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; @@ -1939,20 +1938,21 @@ static int tegra_dc_init(struct host1x_client *client) 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->dc_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->dc_group = dc->group; } - - dc->domain = tegra->domain; } if (dc->soc->wgrps) @@ -2017,13 +2017,13 @@ static int tegra_dc_init(struct host1x_client *client) if (!IS_ERR(primary)) drm_plane_cleanup(primary); - if (group && dc->domain) { - if (group == tegra->group) { - iommu_detach_group(dc->domain, group); - tegra->group = NULL; + if (dc->group) { + if (dc->group && dc->group == tegra->dc_group) { + iommu_detach_group(tegra->domain, dc->group); + tegra->dc_group = NULL; } - dc->domain = NULL; + iommu_group_put(dc->group); } return err; @@ -2032,7 +2032,6 @@ static int tegra_dc_init(struct host1x_client *client) 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; @@ -2045,13 +2044,13 @@ static int tegra_dc_exit(struct host1x_client *client) return err; } - if (group && dc->domain) { - if (group == tegra->group) { - iommu_detach_group(dc->domain, group); - tegra->group = NULL; + if (dc->group) { + if (dc->group && dc->group == tegra->dc_group) { + iommu_detach_group(tegra->domain, dc->group); + tegra->dc_group = NULL; } - dc->domain = NULL; + iommu_group_put(dc->group); } host1x_syncpt_free(dc->syncpt); diff --git a/drivers/gpu/drm/tegra/dc.h b/drivers/gpu/drm/tegra/dc.h index ca5cac6bf8ea..5ca4e07333bb 100644 --- a/drivers/gpu/drm/tegra/dc.h +++ b/drivers/gpu/drm/tegra/dc.h @@ -94,7 +94,7 @@ struct tegra_dc { const struct tegra_dc_soc_info *soc; - struct iommu_domain *domain; + struct iommu_group *group; }; static inline struct tegra_dc * diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h index 4f41aaec8530..7777640a6911 100644 --- a/drivers/gpu/drm/tegra/drm.h +++ b/drivers/gpu/drm/tegra/drm.h @@ -46,7 +46,7 @@ struct tegra_drm { struct drm_device *drm; struct iommu_domain *domain; - struct iommu_group *group; + struct iommu_group *dc_group; struct mutex mm_lock; struct drm_mm mm; -- 2.17.0