[PATCH 1/7] iommu/omap: Do bus_set_iommu() only if probe() succeeds

From: Florian Vaussard
Date: Tue Dec 17 2013 - 08:02:57 EST


Currently, bus_set_iommu() is done in omap_iommu_init(). However,
omap_iommu_probe() can fail in a number of ways, leaving the platform
bus with a dangling reference to a non-initialized iommu. Perform
bus_set_iommu() only if omap_iommu_probe() succeed.

Signed-off-by: Florian Vaussard <florian.vaussard@xxxxxxx>
---
drivers/iommu/omap-iommu.c | 207 +++++++++++++++++++++++----------------------
1 file changed, 104 insertions(+), 103 deletions(-)

diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index bcd78a7..ee83bcc 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -930,107 +930,6 @@ static void omap_iommu_detach(struct omap_iommu *obj)
dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
}

-/*
- * OMAP Device MMU(IOMMU) detection
- */
-static int omap_iommu_probe(struct platform_device *pdev)
-{
- int err = -ENODEV;
- int irq;
- struct omap_iommu *obj;
- struct resource *res;
- struct iommu_platform_data *pdata = pdev->dev.platform_data;
-
- obj = kzalloc(sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL);
- if (!obj)
- return -ENOMEM;
-
- obj->nr_tlb_entries = pdata->nr_tlb_entries;
- obj->name = pdata->name;
- obj->dev = &pdev->dev;
- obj->ctx = (void *)obj + sizeof(*obj);
- obj->da_start = pdata->da_start;
- obj->da_end = pdata->da_end;
-
- spin_lock_init(&obj->iommu_lock);
- mutex_init(&obj->mmap_lock);
- spin_lock_init(&obj->page_table_lock);
- INIT_LIST_HEAD(&obj->mmap);
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res) {
- err = -ENODEV;
- goto err_mem;
- }
-
- res = request_mem_region(res->start, resource_size(res),
- dev_name(&pdev->dev));
- if (!res) {
- err = -EIO;
- goto err_mem;
- }
-
- obj->regbase = ioremap(res->start, resource_size(res));
- if (!obj->regbase) {
- err = -ENOMEM;
- goto err_ioremap;
- }
-
- irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- err = -ENODEV;
- goto err_irq;
- }
- err = request_irq(irq, iommu_fault_handler, IRQF_SHARED,
- dev_name(&pdev->dev), obj);
- if (err < 0)
- goto err_irq;
- platform_set_drvdata(pdev, obj);
-
- pm_runtime_irq_safe(obj->dev);
- pm_runtime_enable(obj->dev);
-
- dev_info(&pdev->dev, "%s registered\n", obj->name);
- return 0;
-
-err_irq:
- iounmap(obj->regbase);
-err_ioremap:
- release_mem_region(res->start, resource_size(res));
-err_mem:
- kfree(obj);
- return err;
-}
-
-static int omap_iommu_remove(struct platform_device *pdev)
-{
- int irq;
- struct resource *res;
- struct omap_iommu *obj = platform_get_drvdata(pdev);
-
- iopgtable_clear_entry_all(obj);
-
- irq = platform_get_irq(pdev, 0);
- free_irq(irq, obj);
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(res->start, resource_size(res));
- iounmap(obj->regbase);
-
- pm_runtime_disable(obj->dev);
-
- dev_info(&pdev->dev, "%s removed\n", obj->name);
- kfree(obj);
- return 0;
-}
-
-static struct platform_driver omap_iommu_driver = {
- .probe = omap_iommu_probe,
- .remove = omap_iommu_remove,
- .driver = {
- .name = "omap-iommu",
- },
-};
-
static void iopte_cachep_ctor(void *iopte)
{
clean_dcache_area(iopte, IOPTE_TABLE_SIZE);
@@ -1265,6 +1164,110 @@ static struct iommu_ops omap_iommu_ops = {
.pgsize_bitmap = OMAP_IOMMU_PGSIZES,
};

+/*
+ * OMAP Device MMU(IOMMU) detection
+ */
+static int omap_iommu_probe(struct platform_device *pdev)
+{
+ int err = -ENODEV;
+ int irq;
+ struct omap_iommu *obj;
+ struct resource *res;
+ struct iommu_platform_data *pdata = pdev->dev.platform_data;
+
+ obj = kzalloc(sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL);
+ if (!obj)
+ return -ENOMEM;
+
+ obj->nr_tlb_entries = pdata->nr_tlb_entries;
+ obj->name = pdata->name;
+ obj->dev = &pdev->dev;
+ obj->ctx = (void *)obj + sizeof(*obj);
+ obj->da_start = pdata->da_start;
+ obj->da_end = pdata->da_end;
+
+ spin_lock_init(&obj->iommu_lock);
+ mutex_init(&obj->mmap_lock);
+ spin_lock_init(&obj->page_table_lock);
+ INIT_LIST_HEAD(&obj->mmap);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ err = -ENODEV;
+ goto err_mem;
+ }
+
+ res = request_mem_region(res->start, resource_size(res),
+ dev_name(&pdev->dev));
+ if (!res) {
+ err = -EIO;
+ goto err_mem;
+ }
+
+ obj->regbase = ioremap(res->start, resource_size(res));
+ if (!obj->regbase) {
+ err = -ENOMEM;
+ goto err_ioremap;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ err = -ENODEV;
+ goto err_irq;
+ }
+
+ err = request_irq(irq, iommu_fault_handler, IRQF_SHARED,
+ dev_name(&pdev->dev), obj);
+ if (err < 0)
+ goto err_irq;
+ platform_set_drvdata(pdev, obj);
+
+ bus_set_iommu(&platform_bus_type, &omap_iommu_ops);
+
+ pm_runtime_irq_safe(obj->dev);
+ pm_runtime_enable(obj->dev);
+
+ dev_info(&pdev->dev, "%s registered\n", obj->name);
+ return 0;
+
+err_irq:
+ iounmap(obj->regbase);
+err_ioremap:
+ release_mem_region(res->start, resource_size(res));
+err_mem:
+ kfree(obj);
+ return err;
+}
+
+static int omap_iommu_remove(struct platform_device *pdev)
+{
+ int irq;
+ struct resource *res;
+ struct omap_iommu *obj = platform_get_drvdata(pdev);
+
+ iopgtable_clear_entry_all(obj);
+
+ irq = platform_get_irq(pdev, 0);
+ free_irq(irq, obj);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(res->start, resource_size(res));
+ iounmap(obj->regbase);
+
+ pm_runtime_disable(obj->dev);
+
+ dev_info(&pdev->dev, "%s removed\n", obj->name);
+ kfree(obj);
+ return 0;
+}
+
+static struct platform_driver omap_iommu_driver = {
+ .probe = omap_iommu_probe,
+ .remove = omap_iommu_remove,
+ .driver = {
+ .name = "omap-iommu",
+ },
+};
+
static int __init omap_iommu_init(void)
{
struct kmem_cache *p;
@@ -1277,8 +1280,6 @@ static int __init omap_iommu_init(void)
return -ENOMEM;
iopte_cachep = p;

- bus_set_iommu(&platform_bus_type, &omap_iommu_ops);
-
return platform_driver_register(&omap_iommu_driver);
}
/* must be ready before omap3isp is probed */
--
1.8.1.2

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