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authorJason Wang <jasowang@redhat.com>2016-12-30 18:09:13 +0800
committerMichael S. Tsirkin <mst@redhat.com>2017-01-10 05:56:58 +0200
commit052c8fa9983f553fdfa0d61034774070dd639c2b (patch)
tree5883498a87ba78e92ec7d11e91cf1d813fab3050 /exec.c
parent2d3fc5816eb629a14f8516bf3c964d7f266870c0 (diff)
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exec: introduce address_space_get_iotlb_entry()
This patch introduces a helper to query the iotlb entry for a possible iova. This will be used by later device IOTLB API to enable the capability for a dataplane (e.g vhost) to query the IOTLB. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Crosthwaite <crosthwaite.peter@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'exec.c')
-rw-r--r--exec.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/exec.c b/exec.c
index 8d4bb0e..47835c1 100644
--- a/exec.c
+++ b/exec.c
@@ -449,6 +449,39 @@ address_space_translate_internal(AddressSpaceDispatch *d, hwaddr addr, hwaddr *x
}
/* Called from RCU critical section */
+IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
+ bool is_write)
+{
+ IOMMUTLBEntry iotlb = {0};
+ MemoryRegionSection *section;
+ MemoryRegion *mr;
+
+ for (;;) {
+ AddressSpaceDispatch *d = atomic_rcu_read(&as->dispatch);
+ section = address_space_lookup_region(d, addr, false);
+ addr = addr - section->offset_within_address_space
+ + section->offset_within_region;
+ mr = section->mr;
+
+ if (!mr->iommu_ops) {
+ break;
+ }
+
+ iotlb = mr->iommu_ops->translate(mr, addr, is_write);
+ if (!(iotlb.perm & (1 << is_write))) {
+ iotlb.target_as = NULL;
+ break;
+ }
+
+ addr = ((iotlb.translated_addr & ~iotlb.addr_mask)
+ | (addr & iotlb.addr_mask));
+ as = iotlb.target_as;
+ }
+
+ return iotlb;
+}
+
+/* Called from RCU critical section */
MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr,
hwaddr *xlat, hwaddr *plen,
bool is_write)