[PATCH 01/15] iommu: Introduce domain_alloc and domain_free iommu_ops

Joerg Roedel
2015-01-26T23:51:55Z

These new call-backs defer the allocation and destruction of
'struct iommu_domain' to the iommu driver. This allows
drivers to embed this struct into their private domain
structures and to get rid of the domain_init and
domain_destroy call-backs when all drivers have been
converted.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/iommu.c | 29 +++++++++++++++++++++--------
include/linux/iommu.h | 5 +++++
2 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index f7718d7..684efc0 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -900,26 +900,34 @@ EXPORT_SYMBOL_GPL(iommu_set_fault_handler);

struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
{
+ const struct iommu_ops *ops;
struct iommu_domain *domain;
- int ret;

if (bus == NULL || bus->iommu_ops == NULL)
return NULL;

- domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+ ops = bus->iommu_ops;
+
+ if (ops->domain_alloc)
+ domain = ops->domain_alloc();
+ else
+ domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+
if (!domain)
return NULL;

domain->ops = bus->iommu_ops;

- ret = domain->ops->domain_init(domain);
- if (ret)
+ if (ops->domain_init && domain->ops->domain_init(domain))
goto out_free;

return domain;

out_free:
- kfree(domain);
+ if (ops->domain_free)
+ ops->domain_free(domain);
+ else
+ kfree(domain);

return NULL;
}
@@ -927,10 +935,15 @@ EXPORT_SYMBOL_GPL(iommu_domain_alloc);

void iommu_domain_free(struct iommu_domain *domain)
{
- if (likely(domain->ops->domain_destroy != NULL))
- domain->ops->domain_destroy(domain);
+ const struct iommu_ops *ops = domain->ops;

- kfree(domain);
+ if (likely(ops->domain_destroy != NULL))
+ ops->domain_destroy(domain);
+
+ if (ops->domain_free)
+ ops->domain_free(domain);
+ else
+ kfree(domain);
}
EXPORT_SYMBOL_GPL(iommu_domain_free);

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 38daa45..69d1d12 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -115,6 +115,11 @@ struct iommu_ops {
bool (*capable)(enum iommu_cap);
int (*domain_init)(struct iommu_domain *domain);
void (*domain_destroy)(struct iommu_domain *domain);
+
+ /* Domain allocation and freeing by the iommu driver */
+ struct iommu_domain *(*domain_alloc)(void);
+ void (*domain_free)(struct iommu_domain *);
+
int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
int (*map)(struct iommu_domain *domain, unsigned long iova,
--
1.8.4.5