On 2018/8/9 18:46, Robin Murphy wrote:

On 06/08/18 13:27, Zhen Lei wrote:

quoted

1. Save the related domain pointer in struct iommu_dma_cookie, make iovad
    capable call domain->ops->flush_iotlb_all to flush TLB.
2. During the iommu domain initialization phase, base on domain->non_strict
    field to check whether non-strict mode is supported or not. If so, call
    init_iova_flush_queue to register iovad->flush_cb callback.
3. All unmap(contains iova-free) APIs will finally invoke __iommu_dma_unmap
    -->iommu_dma_free_iova. If the domain is non-strict, call queue_iova to
    put off iova freeing.

Signed-off-by: Zhen Lei <redacted>
---
  drivers/iommu/dma-iommu.c | 23 +++++++++++++++++++++++
  drivers/iommu/iommu.c     |  1 +
  include/linux/iommu.h     |  1 +
  3 files changed, 25 insertions(+)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index ddcbbdb..213e62a 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c

@@ -55,6 +55,7 @@ struct iommu_dma_cookie {
      };
      struct list_head        msi_page_list;
      spinlock_t            msi_lock;
+    struct iommu_domain        *domain;
  };

  static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie)

@@ -257,6 +258,17 @@ static int iova_reserve_iommu_regions(struct device *dev,
      return ret;
  }

+static void iommu_dma_flush_iotlb_all(struct iova_domain *iovad)
+{
+    struct iommu_dma_cookie *cookie;
+    struct iommu_domain *domain;
+
+    cookie = container_of(iovad, struct iommu_dma_cookie, iovad);
+    domain = cookie->domain;
+
+    domain->ops->flush_iotlb_all(domain);
+}
+
  /**
   * iommu_dma_init_domain - Initialise a DMA mapping domain
   * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie()

@@ -308,6 +320,14 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
      }

      init_iova_domain(iovad, 1UL << order, base_pfn);
+
+    if (domain->non_strict) {
+        BUG_ON(!domain->ops->flush_iotlb_all);
+
+        cookie->domain = domain;

cookie->domain will only be non-NULL if domain->non_strict is true...

quoted

+        init_iova_flush_queue(iovad, iommu_dma_flush_iotlb_all, NULL);
+    }
+
      if (!dev)
          return 0;

@@ -390,6 +410,9 @@ static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie,
      /* The MSI case is only ever cleaning up its most recent allocation */
      if (cookie->type == IOMMU_DMA_MSI_COOKIE)
          cookie->msi_iova -= size;
+    else if (cookie->domain && cookie->domain->non_strict)

...so we don't need to re-check non_strict every time here.

OK, I will change it to a comment.

quoted

+        queue_iova(iovad, iova_pfn(iovad, iova),
+                size >> iova_shift(iovad), 0);
      else
          free_iova_fast(iovad, iova_pfn(iovad, iova),
                  size >> iova_shift(iovad));

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 63b3756..7811fde 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c

@@ -1263,6 +1263,7 @@ static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,

      domain->ops  = bus->iommu_ops;
      domain->type = type;
+    domain->non_strict = 0;
      /* Assume all sizes by default; the driver may override this later */
      domain->pgsize_bitmap  = bus->iommu_ops->pgsize_bitmap;

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 19938ee..0a0fb48 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h

@@ -88,6 +88,7 @@ struct iommu_domain_geometry {

  struct iommu_domain {
      unsigned type;
+    int non_strict;

bool?

OK

Robin.

quoted

      const struct iommu_ops *ops;
      unsigned long pgsize_bitmap;    /* Bitmap of page sizes in use */
      iommu_fault_handler_t handler;
-- 
1.8.3

.

-- 
Thanks!
BestRegards