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>

diff --git a/hw/core/numa.c b/hw/core/numa.c
index 134ebc2b7247b6d0dbdd3786f1b358a4eb1639e0..4c58b2348d604dd918377490102f95ef2e28469d 100644 (file)
--- a/hw/core/numa.c
+++ b/hw/core/numa.c
@@ -805,11 +805,12 @@ void query_numa_node_mem(NumaNodeMem node_mem[], MachineState *ms)
 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 @@ void ram_block_notifier_remove(RAMBlockNotifier *n)
     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);
+        }
     }
 }

diff --git a/hw/i386/xen/xen-mapcache.c b/hw/i386/xen/xen-mapcache.c
index e82b7dcdd2e5363e26b99c3bec806c392476634e..bd47c3d672fa488b958353d35af710d3b2c6418b 100644 (file)
--- a/hw/i386/xen/xen-mapcache.c
+++ b/hw/i386/xen/xen-mapcache.c
@@ -169,7 +169,8 @@ static void xen_remap_bucket(MapCacheEntry *entry,
 
     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 @@ static void xen_remap_bucket(MapCacheEntry *entry,
     }
 
     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 @@ static void xen_invalidate_map_cache_entry_unlocked(uint8_t *buffer)
     }
 
     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);

diff --git a/include/exec/ramlist.h b/include/exec/ramlist.h
index 26704aa3b0d75f6c823037fbe2c5b7fedfdd9cbb..ece6497ee24fc4cd7f3914021b8309dcd59d21fa 100644 (file)
--- a/include/exec/ramlist.h
+++ b/include/exec/ramlist.h
@@ -65,15 +65,20 @@ void qemu_mutex_lock_ramlist(void);
 void qemu_mutex_unlock_ramlist(void);
 
 struct RAMBlockNotifier {
-    void (*ram_block_added)(RAMBlockNotifier *n, void *host, size_t size);
-    void (*ram_block_removed)(RAMBlockNotifier *n, void *host, size_t size);
+    void (*ram_block_added)(RAMBlockNotifier *n, void *host, size_t size,
+                            size_t max_size);
+    void (*ram_block_removed)(RAMBlockNotifier *n, void *host, size_t size,
+                              size_t max_size);
+    void (*ram_block_resized)(RAMBlockNotifier *n, void *host, size_t old_size,
+                              size_t new_size);
     QLIST_ENTRY(RAMBlockNotifier) next;
 };
 
 void ram_block_notifier_add(RAMBlockNotifier *n);
 void ram_block_notifier_remove(RAMBlockNotifier *n);
-void ram_block_notify_add(void *host, size_t size);
-void ram_block_notify_remove(void *host, size_t size);
+void ram_block_notify_add(void *host, size_t size, size_t max_size);
+void ram_block_notify_remove(void *host, size_t size, size_t max_size);
+void ram_block_notify_resize(void *host, size_t old_size, size_t new_size);
 
 void ram_block_dump(Monitor *mon);
 

diff --git a/softmmu/physmem.c b/softmmu/physmem.c
index 0a05533ed0e77e48f0445eb6c03f35c6a87a9b31..81ec3b85b9029d7cc035e97db7c9165527df34be 100644 (file)
--- a/softmmu/physmem.c
+++ b/softmmu/physmem.c
@@ -1807,6 +1807,7 @@ static int memory_try_enable_merging(void *addr, size_t len)
  */
 int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp)
 {
+    const ram_addr_t oldsize = block->used_length;
     const ram_addr_t unaligned_size = newsize;
 
     assert(block);
@@ -1843,6 +1844,11 @@ int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp)
         return -EINVAL;
     }
 
+    /* Notify before modifying the ram block and touching the bitmaps. */
+    if (block->host) {
+        ram_block_notify_resize(block->host, oldsize, newsize);
+    }
+
     cpu_physical_memory_clear_dirty_range(block->offset, block->used_length);
     block->used_length = newsize;
     cpu_physical_memory_set_dirty_range(block->offset, block->used_length,
@@ -2010,7 +2016,8 @@ static void ram_block_add(RAMBlock *new_block, Error **errp, bool shared)
             qemu_madvise(new_block->host, new_block->max_length,
                          QEMU_MADV_DONTFORK);
         }
-        ram_block_notify_add(new_block->host, new_block->max_length);
+        ram_block_notify_add(new_block->host, new_block->used_length,
+                             new_block->max_length);
     }
 }
 
@@ -2189,7 +2196,8 @@ void qemu_ram_free(RAMBlock *block)
     }
 
     if (block->host) {
-        ram_block_notify_remove(block->host, block->max_length);
+        ram_block_notify_remove(block->host, block->used_length,
+                                block->max_length);
     }
 
     qemu_mutex_lock_ramlist();

diff --git a/target/i386/hax/hax-mem.c b/target/i386/hax/hax-mem.c
index 35495f5e822fc5111c4e8276e7da058299f27892..8d44edbffdd15526ac5ba082e0f08042ce3480bb 100644 (file)
--- a/target/i386/hax/hax-mem.c
+++ b/target/i386/hax/hax-mem.c
@@ -293,7 +293,8 @@ static MemoryListener hax_memory_listener = {
     .priority = 10,
 };
 
-static void hax_ram_block_added(RAMBlockNotifier *n, void *host, size_t size)
+static void hax_ram_block_added(RAMBlockNotifier *n, void *host, size_t size,
+                                size_t max_size)
 {
     /*
      * We must register each RAM block with the HAXM kernel module, or
@@ -304,7 +305,7 @@ static void hax_ram_block_added(RAMBlockNotifier *n, void *host, size_t size)
      * host physical pages for the RAM block as part of this registration
      * process, hence the name hax_populate_ram().
      */
-    if (hax_populate_ram((uint64_t)(uintptr_t)host, size) < 0) {
+    if (hax_populate_ram((uint64_t)(uintptr_t)host, max_size) < 0) {
         fprintf(stderr, "HAX failed to populate RAM\n");
         abort();
     }

diff --git a/target/i386/sev.c b/target/i386/sev.c
index 9a43be11cb39a5076ff7272e1a8dfed953b19636..41f7800b5f75b7549ea24b7dc8ab78ea18652fc7 100644 (file)
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -180,7 +180,8 @@ sev_set_guest_state(SevGuestState *sev, SevState new_state)
 }
 
 static void
-sev_ram_block_added(RAMBlockNotifier *n, void *host, size_t size)
+sev_ram_block_added(RAMBlockNotifier *n, void *host, size_t size,
+                    size_t max_size)
 {
     int r;
     struct kvm_enc_region range;
@@ -197,19 +198,20 @@ sev_ram_block_added(RAMBlockNotifier *n, void *host, size_t size)
     }
 
     range.addr = (__u64)(unsigned long)host;
-    range.size = size;
+    range.size = max_size;
 
-    trace_kvm_memcrypt_register_region(host, size);
+    trace_kvm_memcrypt_register_region(host, max_size);
     r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_REG_REGION, &range);
     if (r) {
         error_report("%s: failed to register region (%p+%#zx) error '%s'",
-                     __func__, host, size, strerror(errno));
+                     __func__, host, max_size, strerror(errno));
         exit(1);
     }
 }
 
 static void
-sev_ram_block_removed(RAMBlockNotifier *n, void *host, size_t size)
+sev_ram_block_removed(RAMBlockNotifier *n, void *host, size_t size,
+                      size_t max_size)
 {
     int r;
     struct kvm_enc_region range;
@@ -226,13 +228,13 @@ sev_ram_block_removed(RAMBlockNotifier *n, void *host, size_t size)
     }
 
     range.addr = (__u64)(unsigned long)host;
-    range.size = size;
+    range.size = max_size;
 
-    trace_kvm_memcrypt_unregister_region(host, size);
+    trace_kvm_memcrypt_unregister_region(host, max_size);
     r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_UNREG_REGION, &range);
     if (r) {
         error_report("%s: failed to unregister region (%p+%#zx)",
-                     __func__, host, size);
+                     __func__, host, max_size);
     }
 }
 

diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
index 92b956579732845c3698f1fcd958fb79c6863aa6..911115b86e637f7c0f31a29860c4642b68c57594 100644 (file)
--- a/util/vfio-helpers.c
+++ b/util/vfio-helpers.c
@@ -459,26 +459,26 @@ fail_container:
     return ret;
 }
 
-static void qemu_vfio_ram_block_added(RAMBlockNotifier *n,
-                                      void *host, size_t size)
+static void qemu_vfio_ram_block_added(RAMBlockNotifier *n, void *host,
+                                      size_t size, size_t max_size)
 {
     QEMUVFIOState *s = container_of(n, QEMUVFIOState, ram_notifier);
     int ret;
 
-    trace_qemu_vfio_ram_block_added(s, host, size);
-    ret = qemu_vfio_dma_map(s, host, size, false, NULL);
+    trace_qemu_vfio_ram_block_added(s, host, max_size);
+    ret = qemu_vfio_dma_map(s, host, max_size, false, NULL);
     if (ret) {
-        error_report("qemu_vfio_dma_map(%p, %zu) failed: %s", host, size,
+        error_report("qemu_vfio_dma_map(%p, %zu) failed: %s", host, max_size,
                      strerror(-ret));
     }
 }
 
-static void qemu_vfio_ram_block_removed(RAMBlockNotifier *n,
-                                        void *host, size_t size)
+static void qemu_vfio_ram_block_removed(RAMBlockNotifier *n, void *host,
+                                        size_t size, size_t max_size)
 {
     QEMUVFIOState *s = container_of(n, QEMUVFIOState, ram_notifier);
     if (host) {
-        trace_qemu_vfio_ram_block_removed(s, host, size);
+        trace_qemu_vfio_ram_block_removed(s, host, max_size);
         qemu_vfio_dma_unmap(s, host);
     }
 }