With arch_setup_dma_ops now being called late during device's probe after
the device's IOMMU is probed, the notifier trick required to handle the
early setup of dma_ops before the IOMMU group gets created is not
required. So removing the notifiers here.
Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Tested-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
Acked-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
[rm: clean up even more]
Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---
[*] Rebased the series against linux-next. Please note that there is an
conflict while applying this patch against iommu-next because of the
patch [1] "arm64: dma-mapping: Only swizzle DMA ops for IOMMU_DOMAIN_DMA"
not there
[1] https://www.spinics.net/lists/arm-kernel/msg556209.html
arch/arm64/mm/dma-mapping.c | 142 ++++++--------------------------------------
1 file changed, 18 insertions(+), 124 deletions(-)
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 6e295e8..3653c4c 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -814,34 +814,26 @@ static void __iommu_unmap_sg_attrs(struct device *dev,
.mapping_error = iommu_dma_mapping_error,
};
-/*
- * TODO: Right now __iommu_setup_dma_ops() gets called too early to do
- * everything it needs to - the device is only partially created and the
- * IOMMU driver hasn't seen it yet, so it can't have a group. Thus we
- * need this delayed attachment dance. Once IOMMU probe ordering is sorted
- * to move the arch_setup_dma_ops() call later, all the notifier bits below
- * become unnecessary, and will go away.
- */
-struct iommu_dma_notifier_data {
- struct list_head list;
- struct device *dev;
- const struct iommu_ops *ops;
- u64 dma_base;
- u64 size;
-};
-static LIST_HEAD(iommu_dma_masters);
-static DEFINE_MUTEX(iommu_dma_notifier_lock);
+static int __init __iommu_dma_init(void)
+{
+ return iommu_dma_init();
+}
+arch_initcall(__iommu_dma_init);
-static bool do_iommu_attach(struct device *dev, const struct iommu_ops *ops,
- u64 dma_base, u64 size)
+static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+ const struct iommu_ops *ops)
{
- struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
+ struct iommu_domain *domain;
+
+ if (!ops)
+ return;
/*
- * If the IOMMU driver has the DMA domain support that we require,
- * then the IOMMU core will have already configured a group for this
- * device, and allocated the default domain for that group.
+ * The IOMMU core code allocates the default DMA domain, which the
+ * underlying IOMMU driver needs to support via the dma-iommu layer.
*/
+ domain = iommu_get_domain_for_dev(dev);
+
if (!domain)
goto out_err;
@@ -852,109 +844,11 @@ static bool do_iommu_attach(struct device *dev, const struct iommu_ops *ops,
dev->archdata.dma_ops = &iommu_dma_ops;
}
- return true;
+ return;
+
out_err:
pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n",
- dev_name(dev));
- return false;
-}
-
-static void queue_iommu_attach(struct device *dev, const struct iommu_ops *ops,
- u64 dma_base, u64 size)
-{
- struct iommu_dma_notifier_data *iommudata;
-
- iommudata = kzalloc(sizeof(*iommudata), GFP_KERNEL);
- if (!iommudata)
- return;
-
- iommudata->dev = dev;
- iommudata->ops = ops;
- iommudata->dma_base = dma_base;
- iommudata->size = size;
-
- mutex_lock(&iommu_dma_notifier_lock);
- list_add(&iommudata->list, &iommu_dma_masters);
- mutex_unlock(&iommu_dma_notifier_lock);
-}
-
-static int __iommu_attach_notifier(struct notifier_block *nb,
- unsigned long action, void *data)
-{
- struct iommu_dma_notifier_data *master, *tmp;
-
- if (action != BUS_NOTIFY_BIND_DRIVER)
- return 0;
-
- mutex_lock(&iommu_dma_notifier_lock);
- list_for_each_entry_safe(master, tmp, &iommu_dma_masters, list) {
- if (data == master->dev && do_iommu_attach(master->dev,
- master->ops, master->dma_base, master->size)) {
- list_del(&master->list);
- kfree(master);
- break;
- }
- }
- mutex_unlock(&iommu_dma_notifier_lock);
- return 0;
-}
-
-static int __init register_iommu_dma_ops_notifier(struct bus_type *bus)
-{
- struct notifier_block *nb = kzalloc(sizeof(*nb), GFP_KERNEL);
- int ret;
-
- if (!nb)
- return -ENOMEM;
-
- nb->notifier_call = __iommu_attach_notifier;
-
- ret = bus_register_notifier(bus, nb);
- if (ret) {
- pr_warn("Failed to register DMA domain notifier; IOMMU DMA ops unavailable on bus '%s'\n",
- bus->name);
- kfree(nb);
- }
- return ret;
-}
-
-static int __init __iommu_dma_init(void)
-{
- int ret;
-
- ret = iommu_dma_init();
- if (!ret)
- ret = register_iommu_dma_ops_notifier(&platform_bus_type);
- if (!ret)
- ret = register_iommu_dma_ops_notifier(&amba_bustype);
-#ifdef CONFIG_PCI
- if (!ret)
- ret = register_iommu_dma_ops_notifier(&pci_bus_type);
-#endif
- return ret;
-}
-arch_initcall(__iommu_dma_init);
-
-static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
- const struct iommu_ops *ops)
-{
- struct iommu_group *group;
-
- if (!ops)
- return;
- /*
- * TODO: As a concession to the future, we're ready to handle being
- * called both early and late (i.e. after bus_add_device). Once all
- * the platform bus code is reworked to call us late and the notifier
- * junk above goes away, move the body of do_iommu_attach here.
- */
- group = iommu_group_get(dev);
- if (group) {
- do_iommu_attach(dev, ops, dma_base, size);
- iommu_group_put(group);
- } else {
- queue_iommu_attach(dev, ops, dma_base, size);
- }
+ dev_name(dev));
}
void arch_teardown_dma_ops(struct device *dev)
--
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