commit 8f44304c76036ac8544468c9306c5b30d1fdd201
author David Hildenbrand <david@redhat.com> Thu Apr 29 13:27:00 2021 +0200
committer Dr. David Alan Gilbert <dgilbert@redhat.com> Thu May 13 18:21:13 2021 +0100
tree f7243f9d71405efcf1f6288a83d88d3dbe92c674
parent 082851a3af1450fa714e9a0a3ca7cb4b9dbd8855

numa: Teach ram block notifiers about resizeable ram blocks

Ram block notifiers are currently not aware of resizes. To properly
handle resizes during migration, we want to teach ram block notifiers about
resizeable ram.

Introduce the basic infrastructure but keep using max_size in the
existing notifiers. Supply the max_size when adding and removing ram
blocks. Also, notify on resizes.

Acked-by: Paul Durrant <paul@xen.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: xen-devel@lists.xenproject.org
Cc: haxm-team@intel.com
Cc: Paul Durrant <paul@xen.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Wenchao Wang <wenchao.wang@intel.com>
Cc: Colin Xu <colin.xu@intel.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-3-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

hw/core/numa.c

diff --git a/hw/core/numa.c b/hw/core/numa.c
index 134ebc2..4c58b23 100644
--- a/hw/core/numa.c
+++ b/hw/core/numa.c
@@ -805,11 +805,12 @@
 static int ram_block_notify_add_single(RAMBlock *rb, void *opaque)
 {
     const ram_addr_t max_size = qemu_ram_get_max_length(rb);
+    const ram_addr_t size = qemu_ram_get_used_length(rb);
     void *host = qemu_ram_get_host_addr(rb);
     RAMBlockNotifier *notifier = opaque;
 
     if (host) {
-        notifier->ram_block_added(notifier, host, max_size);
+        notifier->ram_block_added(notifier, host, size, max_size);
     }
     return 0;
 }
@@ -826,20 +827,31 @@
     QLIST_REMOVE(n, next);
 }
 
-void ram_block_notify_add(void *host, size_t size)
+void ram_block_notify_add(void *host, size_t size, size_t max_size)
 {
     RAMBlockNotifier *notifier;
 
     QLIST_FOREACH(notifier, &ram_list.ramblock_notifiers, next) {
-        notifier->ram_block_added(notifier, host, size);
+        notifier->ram_block_added(notifier, host, size, max_size);
     }
 }
 
-void ram_block_notify_remove(void *host, size_t size)
+void ram_block_notify_remove(void *host, size_t size, size_t max_size)
 {
     RAMBlockNotifier *notifier;
 
     QLIST_FOREACH(notifier, &ram_list.ramblock_notifiers, next) {
-        notifier->ram_block_removed(notifier, host, size);
+        notifier->ram_block_removed(notifier, host, size, max_size);
+    }
+}
+
+void ram_block_notify_resize(void *host, size_t old_size, size_t new_size)
+{
+    RAMBlockNotifier *notifier;
+
+    QLIST_FOREACH(notifier, &ram_list.ramblock_notifiers, next) {
+        if (notifier->ram_block_resized) {
+            notifier->ram_block_resized(notifier, host, old_size, new_size);
+        }
     }
 }

hw/i386/xen/xen-mapcache.c

diff --git a/hw/i386/xen/xen-mapcache.c b/hw/i386/xen/xen-mapcache.c
index e82b7dc..bd47c3d 100644
--- a/hw/i386/xen/xen-mapcache.c
+++ b/hw/i386/xen/xen-mapcache.c
@@ -169,7 +169,8 @@
 
     if (entry->vaddr_base != NULL) {
         if (!(entry->flags & XEN_MAPCACHE_ENTRY_DUMMY)) {
-            ram_block_notify_remove(entry->vaddr_base, entry->size);
+            ram_block_notify_remove(entry->vaddr_base, entry->size,
+                                    entry->size);
         }
 
         /*
@@ -224,7 +225,7 @@
     }
 
     if (!(entry->flags & XEN_MAPCACHE_ENTRY_DUMMY)) {
-        ram_block_notify_add(vaddr_base, size);
+        ram_block_notify_add(vaddr_base, size, size);
     }
 
     entry->vaddr_base = vaddr_base;
@@ -465,7 +466,7 @@
     }
 
     pentry->next = entry->next;
-    ram_block_notify_remove(entry->vaddr_base, entry->size);
+    ram_block_notify_remove(entry->vaddr_base, entry->size, entry->size);
     if (munmap(entry->vaddr_base, entry->size) != 0) {
         perror("unmap fails");
         exit(-1);