diff mbox

[RFC,v5,03/17] iommu: introduce a reserved iova cookie

Message ID 1456856877-4817-4-git-send-email-eric.auger@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

Eric Auger March 1, 2016, 6:27 p.m. UTC
This patch introduces some new fields in the iommu_domain struct,
dedicated to reserved iova management.

In a similar way as DMA mapping IOVA window, we need to store
information related to a reserved IOVA window.

The reserved_iova_cookie will store the reserved iova_domain
handle. An RB tree indexed by physical address is introduced to
store the host physical addresses bound to reserved IOVAs.

Those physical addresses will correspond to MSI frame base
addresses, also referred to as doorbells. Their number should be
quite limited per domain.

Also a mutex is introduced to protect accesses to the iova_domain
and RB tree.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
---
 drivers/iommu/iommu.c | 1 +
 include/linux/iommu.h | 5 +++++
 2 files changed, 6 insertions(+)

Comments

Julien Grall March 3, 2016, 4:26 p.m. UTC | #1
Hi Eric,

On 01/03/16 18:27, Eric Auger wrote:
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index 0e3b009..7b2bb94 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -1072,6 +1072,7 @@ static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
>
>   	domain->ops  = bus->iommu_ops;
>   	domain->type = type;
> +	mutex_init(&domain->reserved_mutex);

For consistency, the RB-tree reserved_binding_list should be initialized 
too:

domain->reserved_binding_list = RB_ROOT;

Cheers,
Eric Auger March 29, 2016, 5:26 p.m. UTC | #2
Hi Julien,
On 03/03/2016 05:26 PM, Julien Grall wrote:
> Hi Eric,
> 
> On 01/03/16 18:27, Eric Auger wrote:
>> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
>> index 0e3b009..7b2bb94 100644
>> --- a/drivers/iommu/iommu.c
>> +++ b/drivers/iommu/iommu.c
>> @@ -1072,6 +1072,7 @@ static struct iommu_domain
>> *__iommu_domain_alloc(struct bus_type *bus,
>>
>>       domain->ops  = bus->iommu_ops;
>>       domain->type = type;
>> +    mutex_init(&domain->reserved_mutex);
> 
> For consistency, the RB-tree reserved_binding_list should be initialized
> too:
> 
> domain->reserved_binding_list = RB_ROOT;
Sure

Thank you

Eric
> 
> Cheers,
>
diff mbox

Patch

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 0e3b009..7b2bb94 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1072,6 +1072,7 @@  static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
 
 	domain->ops  = bus->iommu_ops;
 	domain->type = type;
+	mutex_init(&domain->reserved_mutex);
 
 	return domain;
 }
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index a4fe04a..0189144 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -82,6 +82,11 @@  struct iommu_domain {
 	void *handler_token;
 	struct iommu_domain_geometry geometry;
 	void *iova_cookie;
+	void *reserved_iova_cookie;
+	/* rb tree indexed by PA, for reserved bindings only */
+	struct rb_root reserved_binding_list;
+	/* protects reserved cookie and rbtree manipulation */
+	struct mutex reserved_mutex;
 };
 
 enum iommu_cap {