1. Patchew
  2. QEMU
  3. [Qemu-devel] [PATCH v2 0/7] VT-d: PT (passthrough) mode support and misc fixes
  4. View patch

[Qemu-devel] [PATCH v2 2/7] memory: remove the last param in memory_region_iommu_replay()

Peter Xu posted 7 patches 8 years, 9 months ago
There is a newer version of this series
[Qemu-devel] [PATCH v2 2/7] memory: remove the last param in memory_region_iommu_replay()
Posted by Peter Xu 8 years, 9 months ago 
We were always passing in that one as "false" to assume that's an read
operation, and we also assume that IOMMU translation would always have
that read permission. A better permission would be IOMMU_NONE since the
replay is after all not a real read operation, but just a page table
rebuilding process.

CC: David Gibson <david@gibson.dropbear.id.au>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 hw/vfio/common.c      | 2 +-
 include/exec/memory.h | 5 +----
 memory.c              | 8 +++-----
 3 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 6b33b9f..d008a4b 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -488,7 +488,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
         QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
 
         memory_region_register_iommu_notifier(giommu->iommu, &giommu->n);
-        memory_region_iommu_replay(giommu->iommu, &giommu->n, false);
+        memory_region_iommu_replay(giommu->iommu, &giommu->n);
 
         return;
     }
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 9047bf3..8721d53 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -731,11 +731,8 @@ void memory_region_register_iommu_notifier(MemoryRegion *mr,
  *
  * @mr: the memory region to observe
  * @n: the notifier to which to replay iommu mappings
- * @is_write: Whether to treat the replay as a translate "write"
- *     through the iommu
  */
-void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n,
-                                bool is_write);
+void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n);
 
 /**
  * memory_region_iommu_replay_all: replay existing IOMMU translations
diff --git a/memory.c b/memory.c
index 47dc107..6b2fdb7 100644
--- a/memory.c
+++ b/memory.c
@@ -1620,12 +1620,10 @@ uint64_t memory_region_iommu_get_min_page_size(MemoryRegion *mr)
     return TARGET_PAGE_SIZE;
 }
 
-void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n,
-                                bool is_write)
+void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n)
 {
     hwaddr addr, granularity;
     IOMMUTLBEntry iotlb;
-    IOMMUAccessFlags flag = is_write ? IOMMU_WO : IOMMU_RO;
 
     /* If the IOMMU has its own replay callback, override */
     if (mr->iommu_ops->replay) {
@@ -1636,7 +1634,7 @@ void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n,
     granularity = memory_region_iommu_get_min_page_size(mr);
 
     for (addr = 0; addr < memory_region_size(mr); addr += granularity) {
-        iotlb = mr->iommu_ops->translate(mr, addr, flag);
+        iotlb = mr->iommu_ops->translate(mr, addr, IOMMU_NONE);
         if (iotlb.perm != IOMMU_NONE) {
             n->notify(n, &iotlb);
         }
@@ -1654,7 +1652,7 @@ void memory_region_iommu_replay_all(MemoryRegion *mr)
     IOMMUNotifier *notifier;
 
     IOMMU_NOTIFIER_FOREACH(notifier, mr) {
-        memory_region_iommu_replay(mr, notifier, false);
+        memory_region_iommu_replay(mr, notifier);
     }
 }
 
-- 
2.7.4
Re: [Qemu-devel] [PATCH v2 2/7] memory: remove the last param in memory_region_iommu_replay()
Posted by David Gibson 8 years, 9 months ago 
On Mon, Apr 17, 2017 at 07:32:05PM +0800, Peter Xu wrote:
> We were always passing in that one as "false" to assume that's an read
> operation, and we also assume that IOMMU translation would always have
> that read permission. A better permission would be IOMMU_NONE since the
> replay is after all not a real read operation, but just a page table
> rebuilding process.
> 
> CC: David Gibson <david@gibson.dropbear.id.au>
> CC: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  hw/vfio/common.c      | 2 +-
>  include/exec/memory.h | 5 +----
>  memory.c              | 8 +++-----
>  3 files changed, 5 insertions(+), 10 deletions(-)
> 
> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
> index 6b33b9f..d008a4b 100644
> --- a/hw/vfio/common.c
> +++ b/hw/vfio/common.c
> @@ -488,7 +488,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
>          QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
>  
>          memory_region_register_iommu_notifier(giommu->iommu, &giommu->n);
> -        memory_region_iommu_replay(giommu->iommu, &giommu->n, false);
> +        memory_region_iommu_replay(giommu->iommu, &giommu->n);
>  
>          return;
>      }
> diff --git a/include/exec/memory.h b/include/exec/memory.h
> index 9047bf3..8721d53 100644
> --- a/include/exec/memory.h
> +++ b/include/exec/memory.h
> @@ -731,11 +731,8 @@ void memory_region_register_iommu_notifier(MemoryRegion *mr,
>   *
>   * @mr: the memory region to observe
>   * @n: the notifier to which to replay iommu mappings
> - * @is_write: Whether to treat the replay as a translate "write"
> - *     through the iommu
>   */
> -void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n,
> -                                bool is_write);
> +void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n);
>  
>  /**
>   * memory_region_iommu_replay_all: replay existing IOMMU translations
> diff --git a/memory.c b/memory.c
> index 47dc107..6b2fdb7 100644
> --- a/memory.c
> +++ b/memory.c
> @@ -1620,12 +1620,10 @@ uint64_t memory_region_iommu_get_min_page_size(MemoryRegion *mr)
>      return TARGET_PAGE_SIZE;
>  }
>  
> -void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n,
> -                                bool is_write)
> +void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n)
>  {
>      hwaddr addr, granularity;
>      IOMMUTLBEntry iotlb;
> -    IOMMUAccessFlags flag = is_write ? IOMMU_WO : IOMMU_RO;
>  
>      /* If the IOMMU has its own replay callback, override */
>      if (mr->iommu_ops->replay) {
> @@ -1636,7 +1634,7 @@ void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n,
>      granularity = memory_region_iommu_get_min_page_size(mr);
>  
>      for (addr = 0; addr < memory_region_size(mr); addr += granularity) {
> -        iotlb = mr->iommu_ops->translate(mr, addr, flag);
> +        iotlb = mr->iommu_ops->translate(mr, addr, IOMMU_NONE);
>          if (iotlb.perm != IOMMU_NONE) {
>              n->notify(n, &iotlb);
>          }
> @@ -1654,7 +1652,7 @@ void memory_region_iommu_replay_all(MemoryRegion *mr)
>      IOMMUNotifier *notifier;
>  
>      IOMMU_NOTIFIER_FOREACH(notifier, mr) {
> -        memory_region_iommu_replay(mr, notifier, false);
> +        memory_region_iommu_replay(mr, notifier);
>      }
>  }
>  

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

Patchew 2.1-devel-b67e4c2

© 2016 - 2026 Red Hat, Inc.