[PATCH 2/5] iommu/omap: Permanently keep iommu_dev pointer in arch_data

From: Joerg Roedel
Date: Fri Mar 31 2017 - 08:11:24 EST


From: Joerg Roedel <jroedel@xxxxxxx>

Instead of finding the matching IOMMU for a device using
string comparision functions, keep the pointer to the
iommu_dev in arch_data permanently populated.

Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
drivers/iommu/omap-iommu.c | 56 ++++++++++++++++++++--------------------------
drivers/iommu/omap-iommu.h | 2 +-
2 files changed, 25 insertions(+), 33 deletions(-)

diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index e9c9b08..45df5c8 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -802,33 +802,14 @@ static irqreturn_t iommu_fault_handler(int irq, void *data)
return IRQ_NONE;
}

-static int device_match_by_alias(struct device *dev, void *data)
-{
- struct omap_iommu *obj = to_iommu(dev);
- const char *name = data;
-
- pr_debug("%s: %s %s\n", __func__, obj->name, name);
-
- return strcmp(obj->name, name) == 0;
-}
-
/**
* omap_iommu_attach() - attach iommu device to an iommu domain
- * @name: name of target omap iommu device
+ * @obj: target omap iommu device
* @iopgd: page table
**/
-static struct omap_iommu *omap_iommu_attach(const char *name, u32 *iopgd)
+static int omap_iommu_attach(struct omap_iommu *obj, u32 *iopgd)
{
int err;
- struct device *dev;
- struct omap_iommu *obj;
-
- dev = driver_find_device(&omap_iommu_driver.driver, NULL, (void *)name,
- device_match_by_alias);
- if (!dev)
- return ERR_PTR(-ENODEV);
-
- obj = to_iommu(dev);

spin_lock(&obj->iommu_lock);

@@ -841,11 +822,13 @@ static struct omap_iommu *omap_iommu_attach(const char *name, u32 *iopgd)
spin_unlock(&obj->iommu_lock);

dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
- return obj;
+
+ return 0;

err_enable:
spin_unlock(&obj->iommu_lock);
- return ERR_PTR(err);
+
+ return err;
}

/**
@@ -1061,11 +1044,11 @@ static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
{
struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
- struct omap_iommu *oiommu;
struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
+ struct omap_iommu *oiommu;
int ret = 0;

- if (!arch_data || !arch_data->name) {
+ if (!arch_data || !arch_data->iommu_dev) {
dev_err(dev, "device doesn't have an associated iommu\n");
return -EINVAL;
}
@@ -1079,15 +1062,17 @@ static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
goto out;
}

+ oiommu = arch_data->iommu_dev;
+
/* get a handle to and enable the omap iommu */
- oiommu = omap_iommu_attach(arch_data->name, omap_domain->pgtable);
- if (IS_ERR(oiommu)) {
- ret = PTR_ERR(oiommu);
+ ret = omap_iommu_attach(oiommu, omap_domain->pgtable);
+ if (ret) {
dev_err(dev, "can't get omap iommu: %d\n", ret);
goto out;
}

- omap_domain->iommu_dev = arch_data->iommu_dev = oiommu;
+ arch_data->domain = omap_domain;
+ omap_domain->iommu_dev = oiommu;
omap_domain->dev = dev;
oiommu->domain = domain;

@@ -1112,7 +1097,8 @@ static void _omap_iommu_detach_dev(struct omap_iommu_domain *omap_domain,

omap_iommu_detach(oiommu);

- omap_domain->iommu_dev = arch_data->iommu_dev = NULL;
+ omap_domain->iommu_dev = NULL;
+ arch_data->domain = NULL;
omap_domain->dev = NULL;
oiommu->domain = NULL;
}
@@ -1216,6 +1202,7 @@ static phys_addr_t omap_iommu_iova_to_phys(struct iommu_domain *domain,
static int omap_iommu_add_device(struct device *dev)
{
struct omap_iommu_arch_data *arch_data;
+ struct omap_iommu *iommu;
struct device_node *np;
struct platform_device *pdev;

@@ -1238,13 +1225,19 @@ static int omap_iommu_add_device(struct device *dev)
return -EINVAL;
}

+ iommu = platform_get_drvdata(pdev);
+ if (!iommu) {
+ of_node_put(np);
+ return -EINVAL;
+ }
+
arch_data = kzalloc(sizeof(*arch_data), GFP_KERNEL);
if (!arch_data) {
of_node_put(np);
return -ENOMEM;
}

- arch_data->name = kstrdup(dev_name(&pdev->dev), GFP_KERNEL);
+ arch_data->iommu_dev = iommu;
dev->archdata.iommu = arch_data;

of_node_put(np);
@@ -1259,7 +1252,6 @@ static void omap_iommu_remove_device(struct device *dev)
if (!dev->of_node || !arch_data)
return;

- kfree(arch_data->name);
kfree(arch_data);
}

diff --git a/drivers/iommu/omap-iommu.h b/drivers/iommu/omap-iommu.h
index 3cd414a..05bd279 100644
--- a/drivers/iommu/omap-iommu.h
+++ b/drivers/iommu/omap-iommu.h
@@ -80,8 +80,8 @@ struct omap_iommu {
* utilize omap-specific plumbing anymore.
*/
struct omap_iommu_arch_data {
- const char *name;
struct omap_iommu *iommu_dev;
+ struct omap_iommu_domain *domain;
};

struct cr_regs {
--
1.9.1