[Qemu-devel] [PATCH 10/11] memory: Add iommu map/unmap notifiers

[David Gibson]

This patch adds a NotifierList to MemoryRegions which represent IOMMUs
allowing other parts of the code to register interest in mappings or
unmappings from the IOMMU.  All IOMMU implementations will need to call
memory_region_notify_iommu() to inform those waiting on the notifier list,
whenever an IOMMU mapping is made or removed.

Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
---
 hw/ppc/spapr_iommu.c  |    8 ++++++++
 include/exec/memory.h |    7 +++++++
 memory.c              |   18 ++++++++++++++++++
 3 files changed, 33 insertions(+)

diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
index 07a6307..6d40485 100644
--- a/hw/ppc/spapr_iommu.c
+++ b/hw/ppc/spapr_iommu.c
@@ -194,6 +194,7 @@ static target_ulong put_tce_emu(sPAPRTCETable *tcet, 
target_ulong ioba,
                                 target_ulong tce)
 {
     sPAPRTCE *tcep;
+    IOMMUTLBEntry entry;
 
     if (ioba >= tcet->window_size) {
         hcall_dprintf("spapr_vio_put_tce on out-of-bounds IOBA 0x"
@@ -204,6 +205,13 @@ static target_ulong put_tce_emu(sPAPRTCETable *tcet, 
target_ulong ioba,
     tcep = tcet->table + (ioba >> SPAPR_TCE_PAGE_SHIFT);
     tcep->tce = tce;
 
+    entry.iova = ioba & ~SPAPR_TCE_PAGE_MASK;
+    entry.translated_addr = tce & ~SPAPR_TCE_PAGE_MASK;
+    entry.addr_mask = SPAPR_TCE_PAGE_MASK;
+    entry.perm[0] = !!(tce & SPAPR_TCE_RO);
+    entry.perm[1] = !!(tce & SPAPR_TCE_WO);
+    memory_region_notify_iommu(&tcet->iommu, entry);
+
     return H_SUCCESS;
 }
 
diff --git a/include/exec/memory.h b/include/exec/memory.h
index cd33439..024b511 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -25,6 +25,7 @@
 #include "exec/iorange.h"
 #include "exec/ioport.h"
 #include "qemu/int128.h"
+#include "qemu/notify.h"
 
 typedef struct MemoryRegionOps MemoryRegionOps;
 typedef struct MemoryRegionPortio MemoryRegionPortio;
@@ -160,6 +161,7 @@ struct MemoryRegion {
     unsigned ioeventfd_nb;
     MemoryRegionIoeventfd *ioeventfds;
     struct AddressSpace *iommu_target_as;
+    NotifierList iommu_notify;
 };
 
 struct MemoryRegionPortio {
@@ -462,6 +464,11 @@ static inline bool memory_region_is_romd(MemoryRegion *mr)
  */
 bool memory_region_is_iommu(MemoryRegion *mr);
 
+void memory_region_notify_iommu(MemoryRegion *mr,
+                                IOMMUTLBEntry entry);
+void memory_region_register_iommu_notifier(MemoryRegion *mr, Notifier *n);
+void memory_region_unregister_iommu_notifier(Notifier *n);
+
 /**
  * memory_region_name: get a memory region's name
  *
diff --git a/memory.c b/memory.c
index c409ee5..b11ca9f 100644
--- a/memory.c
+++ b/memory.c
@@ -1060,6 +1060,7 @@ void memory_region_init_iommu(MemoryRegion *mr,
     mr->terminates = true;  /* then re-forwards */
     mr->destructor = memory_region_destructor_none;
     mr->iommu_target_as = target_as;
+    notifier_list_init(&mr->iommu_notify);
 }
 
 static uint64_t invalid_read(void *opaque, hwaddr addr,
@@ -1175,6 +1176,23 @@ bool memory_region_is_iommu(MemoryRegion *mr)
     return mr->iommu_ops;
 }
 
+void memory_region_register_iommu_notifier(MemoryRegion *mr, Notifier *n)
+{
+    notifier_list_add(&mr->iommu_notify, n);
+}
+
+void memory_region_unregister_iommu_notifier(Notifier *n)
+{
+    notifier_remove(n);
+}
+
+void memory_region_notify_iommu(MemoryRegion *mr,
+                                IOMMUTLBEntry entry)
+{
+    assert(memory_region_is_iommu(mr));
+    notifier_list_notify(&mr->iommu_notify, &entry);
+}
+
 void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client)
 {
     uint8_t mask = 1 << client;
-- 
1.7.10.4