Hi,
On 04/20/2016 07:05 PM, Robin Murphy wrote:
> On 19/04/16 17:56, Eric Auger wrote:
>> Now reserved bindings can exist, destroy them when destroying
>> the reserved iova domain. iommu_map is not supposed to be atomic,
>> hence the extra complexity in the locking.
>>
>> Signed-off-by: Eric Auger <eric.au...@linaro.org>
>>
>> ---
>> v6 -> v7:
>> - remove [PATCH v6 7/7] dma-reserved-iommu: iommu_unmap_reserved and
>> destroy the bindings in iommu_free_reserved_iova_domain
>>
>> v5 -> v6:
>> - use spin_lock instead of mutex
>>
>> v3 -> v4:
>> - previously "iommu/arm-smmu: relinquish reserved resources on
>> domain deletion"
>> ---
>> drivers/iommu/dma-reserved-iommu.c | 34
>> ++++++++++++++++++++++++++++------
>> 1 file changed, 28 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/iommu/dma-reserved-iommu.c
>> b/drivers/iommu/dma-reserved-iommu.c
>> index 426d339..2522235 100644
>> --- a/drivers/iommu/dma-reserved-iommu.c
>> +++ b/drivers/iommu/dma-reserved-iommu.c
>> @@ -157,14 +157,36 @@ void iommu_free_reserved_iova_domain(struct
>> iommu_domain *domain)
>> unsigned long flags;
>> int ret = 0;
>>
>> - spin_lock_irqsave(&domain->reserved_lock, flags);
>> -
>> - rid = (struct reserved_iova_domain *)domain->reserved_iova_cookie;
>> - if (!rid) {
>> - ret = -EINVAL;
>> - goto unlock;
>> + while (1) {
>> + struct iommu_reserved_binding *b;
>> + struct rb_node *node;
>> + dma_addr_t iova;
>> + size_t size;
>> +
>> + spin_lock_irqsave(&domain->reserved_lock, flags);
>> +
>> + rid = (struct reserved_iova_domain *)
>> + domain->reserved_iova_cookie;
>
> Same comment about casting as before.
OK
>
>> + if (!rid) {
>> + ret = -EINVAL;
>> + goto unlock;
>> + }
>> +
>> + node = rb_first(&domain->reserved_binding_list);
>> + if (!node)
>> + break;
>> + b = rb_entry(node, struct iommu_reserved_binding, node);
>> +
>> + iova = b->iova;
>> + size = b->size;
>> +
>> + while (!kref_put(&b->kref, reserved_binding_release))
>> + ;
>
> Since you're freeing the thing anyway, why not just call the function
> directly?
makes sense indeed.
Thanks
Eric
>
>> + spin_unlock_irqrestore(&domain->reserved_lock, flags);
>> + iommu_unmap(domain, iova, size);
>> }
>>
>> + domain->reserved_binding_list = RB_ROOT;
>> domain->reserved_iova_cookie = NULL;
>> unlock:
>> spin_unlock_irqrestore(&domain->reserved_lock, flags);
>>
>
