[PATCH 5.18 667/879] iommu/mediatek: Add mutex for m4u_group and m4u_dom in data

Greg Kroah-Hartman
2022-06-08T01:53:59Z

From: Yong Wu <yong.wu@mediatek.com>

[ Upstream commit 0e5a3f2e630b28e88e018655548212ef8eb4dfcb ]

Add a mutex to protect the data in the structure mtk_iommu_data,
like ->"m4u_group" ->"m4u_dom". For the internal data, we should
protect it in ourselves driver. Add a mutex for this.
This could be a fix for the multi-groups support.

Fixes: c3045f39244e ("iommu/mediatek: Support for multi domains")
Signed-off-by: Yunfei Wang <yf.wang@mediatek.com>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20220503071427.2285-8-yong.wu@mediatek.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/mtk_iommu.c | 13 +++++++++++--
drivers/iommu/mtk_iommu.h | 2 ++
2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 81b8db450eac..3413cc98e57e 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -464,15 +464,16 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain,
dom->data = data;
}

+ mutex_lock(&data->mutex);
if (!data->m4u_dom) { /* Initialize the M4U HW */
ret = pm_runtime_resume_and_get(m4udev);
if (ret < 0)
- return ret;
+ goto err_unlock;

ret = mtk_iommu_hw_init(data);
if (ret) {
pm_runtime_put(m4udev);
- return ret;
+ goto err_unlock;
}
data->m4u_dom = dom;
writel(dom->cfg.arm_v7s_cfg.ttbr & MMU_PT_ADDR_MASK,
@@ -480,9 +481,14 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain,

pm_runtime_put(m4udev);
}
+ mutex_unlock(&data->mutex);

mtk_iommu_config(data, dev, true, domid);
return 0;
+
+err_unlock:
+ mutex_unlock(&data->mutex);
+ return ret;
}

static void mtk_iommu_detach_device(struct iommu_domain *domain,
@@ -622,6 +628,7 @@ static struct iommu_group *mtk_iommu_device_group(struct device *dev)
if (domid < 0)
return ERR_PTR(domid);

+ mutex_lock(&data->mutex);
group = data->m4u_group[domid];
if (!group) {
group = iommu_group_alloc();
@@ -630,6 +637,7 @@ static struct iommu_group *mtk_iommu_device_group(struct device *dev)
} else {
iommu_group_ref_get(group);
}
+ mutex_unlock(&data->mutex);
return group;
}

@@ -910,6 +918,7 @@ static int mtk_iommu_probe(struct platform_device *pdev)
}

platform_set_drvdata(pdev, data);
+ mutex_init(&data->mutex);

ret = iommu_device_sysfs_add(&data->iommu, dev, NULL,
"mtk-iommu.%pa", &ioaddr);
diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index b742432220c5..5e8da947affc 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h
@@ -80,6 +80,8 @@ struct mtk_iommu_data {

struct dma_iommu_mapping *mapping; /* For mtk_iommu_v1.c */

+ struct mutex mutex; /* Protect m4u_group/m4u_dom above */
+
struct list_head list;
struct mtk_smi_larb_iommu larb_imu[MTK_LARB_NR_MAX];
};
--
2.35.1