[Qemu-devel] [PATCHv2 0/3] qemu: memory notifiers

["Michael S. Tsirkin" <mst@redhat.com>]

This patch against qemu upstream adds notifiers hook which lets backends
get notified on memory changes, and converts kvm to use it.  It survived
light testing. Avi, could you please take a look at this patch?
Thanks!


---
 cpu-common.h |   19 +++++++++++++++++
 exec.c       |   62 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 78 insertions(+), 3 deletions(-)

diff --git a/cpu-common.h b/cpu-common.h
index 6302372..0ec9b72 100644
--- a/cpu-common.h
+++ b/cpu-common.h
@@ -8,6 +8,7 @@
 #endif
 
 #include "bswap.h"
+#include "qemu-queue.h"
 
 /* address in the RAM (different from a physical address) */
 typedef unsigned long ram_addr_t;
@@ -61,6 +62,24 @@ void cpu_physical_memory_unmap(void *buffer, target_phys_addr_t len,
 void *cpu_register_map_client(void *opaque, void (*callback)(void *opaque));
 void cpu_unregister_map_client(void *cookie);
 
+struct CPUPhysMemoryClient;
+typedef struct CPUPhysMemoryClient CPUPhysMemoryClient;
+struct CPUPhysMemoryClient {
+    void (*set_memory)(struct CPUPhysMemoryClient *client,
+                       target_phys_addr_t start_addr,
+                       ram_addr_t size,
+                       ram_addr_t phys_offset);
+    int (*sync_dirty_bitmap)(struct CPUPhysMemoryClient *client,
+                             target_phys_addr_t start_addr,
+                             target_phys_addr_t end_addr);
+    int (*migration_log)(struct CPUPhysMemoryClient *client,
+                         int enable);
+    QLIST_ENTRY(CPUPhysMemoryClient) list;
+};
+
+void cpu_register_phys_memory_client(CPUPhysMemoryClient *);
+void cpu_unregister_phys_memory_client(CPUPhysMemoryClient *);
+
 uint32_t ldub_phys(target_phys_addr_t addr);
 uint32_t lduw_phys(target_phys_addr_t addr);
 uint32_t ldl_phys(target_phys_addr_t addr);
diff --git a/exec.c b/exec.c
index 7b7fb5b..daebde5 100644
--- a/exec.c
+++ b/exec.c
@@ -1880,11 +1880,16 @@ void cpu_physical_memory_reset_dirty(ram_addr_t start, ram_addr_t end,
 
 int cpu_physical_memory_set_dirty_tracking(int enable)
 {
+    int ret;
     in_migration = enable;
     if (kvm_enabled()) {
-        return kvm_set_migration_log(enable);
+        ret = kvm_set_migration_log(enable);
     }
-    return 0;
+    if (ret < 0) {
+        return ret;
+    }
+    ret = cpu_notify_migration_log(!!enable);
+    return ret;
 }
 
 int cpu_physical_memory_get_dirty_tracking(void)
@@ -1897,8 +1902,13 @@ int cpu_physical_sync_dirty_bitmap(target_phys_addr_t start_addr,
 {
     int ret = 0;
 
-    if (kvm_enabled())
+    if (kvm_enabled()) {
         ret = kvm_physical_sync_dirty_bitmap(start_addr, end_addr);
+    }
+    if (ret < 0) {
+        return ret;
+    }
+    ret = cpu_notify_sync_dirty_bitmap(start_addr, end_addr);
     return ret;
 }
 
@@ -2313,6 +2323,8 @@ void cpu_register_physical_memory_offset(target_phys_addr_t start_addr,
     if (kvm_enabled())
         kvm_set_phys_mem(start_addr, size, phys_offset);
 
+    cpu_notify_set_memory(start_addr, size, phys_offset);
+
     if (phys_offset == IO_MEM_UNASSIGNED) {
         region_offset = start_addr;
     }
@@ -3214,6 +3226,50 @@ static void cpu_notify_map_clients(void)
     }
 }
 
+static QLIST_HEAD(memory_client_list, CPUPhysMemoryClient) memory_client_list
+    = QLIST_HEAD_INITIALIZER(memory_client_list);
+
+void cpu_register_phys_memory_client(CPUPhysMemoryClient *client)
+{
+    QLIST_INSERT_HEAD(&memory_client_list, client, list);
+}
+
+void cpu_unregister_phys_memory_client(CPUPhysMemoryClient *client)
+{
+    QLIST_REMOVE(client, list);
+}
+
+static void cpu_notify_set_memory(target_phys_addr_t start_addr,
+				  ram_addr_t size,
+				  ram_addr_t phys_offset)
+{
+    CPUPhysMemoryClient *client;
+    QLIST_FOREACH(client, &memory_client_list, list) {
+        client->set_memory(client, start_addr, size, phys_offset);
+    }
+}
+
+static int cpu_notify_sync_dirty_bitmap(target_phys_addr_t start,
+					target_phys_addr_t end)
+{
+    QLIST_FOREACH(client, &memory_client_list, list) {
+        int r = client->sync_dirty_bitmap(client, start, end);
+        if (r < 0)
+            return r;
+    }
+    return 0;
+}
+
+static int cpu_notify_migration_log(int enable)
+{
+    QLIST_FOREACH(client, &memory_client_list, list) {
+        int r = client->migration_log(client, enable);
+        if (r < 0)
+            return r;
+    }
+    return 0;
+}
+
 /* Map a physical memory region into a host virtual address.
  * May map a subset of the requested range, given by and returned in *plen.
  * May return NULL if resources needed to perform the mapping are exhausted.
-- 
1.6.6.rc1.43.gf55cc



Michael S. Tsirkin (3):
  qemu: memory notifiers
  kvm: move kvm_set_phys_mem around
  kvm: move kvm to use memory notifiers

 cpu-common.h |   19 ++++
 exec.c       |  108 +++++++++++++++++++--
 kvm-all.c    |  310 +++++++++++++++++++++++++++++++--------------------------
 kvm.h        |    8 --
 4 files changed, 287 insertions(+), 158 deletions(-)