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-rw-r--r--src/backends/hostmem.c374
1 files changed, 374 insertions, 0 deletions
diff --git a/src/backends/hostmem.c b/src/backends/hostmem.c
new file mode 100644
index 0000000..1b4eb45
--- /dev/null
+++ b/src/backends/hostmem.c
@@ -0,0 +1,374 @@
+/*
+ * QEMU Host Memory Backend
+ *
+ * Copyright (C) 2013-2014 Red Hat Inc
+ *
+ * Authors:
+ * Igor Mammedov <imammedo@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#include "sysemu/hostmem.h"
+#include "hw/boards.h"
+#include "qapi/visitor.h"
+#include "qapi-types.h"
+#include "qapi-visit.h"
+#include "qemu/config-file.h"
+#include "qom/object_interfaces.h"
+
+#ifdef CONFIG_NUMA
+#include <numaif.h>
+QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_DEFAULT != MPOL_DEFAULT);
+QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_PREFERRED != MPOL_PREFERRED);
+QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_BIND != MPOL_BIND);
+QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_INTERLEAVE != MPOL_INTERLEAVE);
+#endif
+
+static void
+host_memory_backend_get_size(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+ uint64_t value = backend->size;
+
+ visit_type_size(v, &value, name, errp);
+}
+
+static void
+host_memory_backend_set_size(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+ Error *local_err = NULL;
+ uint64_t value;
+
+ if (memory_region_size(&backend->mr)) {
+ error_setg(&local_err, "cannot change property value");
+ goto out;
+ }
+
+ visit_type_size(v, &value, name, &local_err);
+ if (local_err) {
+ goto out;
+ }
+ if (!value) {
+ error_setg(&local_err, "Property '%s.%s' doesn't take value '%"
+ PRIu64 "'", object_get_typename(obj), name, value);
+ goto out;
+ }
+ backend->size = value;
+out:
+ error_propagate(errp, local_err);
+}
+
+static void
+host_memory_backend_get_host_nodes(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+ uint16List *host_nodes = NULL;
+ uint16List **node = &host_nodes;
+ unsigned long value;
+
+ value = find_first_bit(backend->host_nodes, MAX_NODES);
+ if (value == MAX_NODES) {
+ return;
+ }
+
+ *node = g_malloc0(sizeof(**node));
+ (*node)->value = value;
+ node = &(*node)->next;
+
+ do {
+ value = find_next_bit(backend->host_nodes, MAX_NODES, value + 1);
+ if (value == MAX_NODES) {
+ break;
+ }
+
+ *node = g_malloc0(sizeof(**node));
+ (*node)->value = value;
+ node = &(*node)->next;
+ } while (true);
+
+ visit_type_uint16List(v, &host_nodes, name, errp);
+}
+
+static void
+host_memory_backend_set_host_nodes(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+#ifdef CONFIG_NUMA
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+ uint16List *l = NULL;
+
+ visit_type_uint16List(v, &l, name, errp);
+
+ while (l) {
+ bitmap_set(backend->host_nodes, l->value, 1);
+ l = l->next;
+ }
+#else
+ error_setg(errp, "NUMA node binding are not supported by this QEMU");
+#endif
+}
+
+static int
+host_memory_backend_get_policy(Object *obj, Error **errp G_GNUC_UNUSED)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+ return backend->policy;
+}
+
+static void
+host_memory_backend_set_policy(Object *obj, int policy, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+ backend->policy = policy;
+
+#ifndef CONFIG_NUMA
+ if (policy != HOST_MEM_POLICY_DEFAULT) {
+ error_setg(errp, "NUMA policies are not supported by this QEMU");
+ }
+#endif
+}
+
+static bool host_memory_backend_get_merge(Object *obj, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+
+ return backend->merge;
+}
+
+static void host_memory_backend_set_merge(Object *obj, bool value, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+
+ if (!memory_region_size(&backend->mr)) {
+ backend->merge = value;
+ return;
+ }
+
+ if (value != backend->merge) {
+ void *ptr = memory_region_get_ram_ptr(&backend->mr);
+ uint64_t sz = memory_region_size(&backend->mr);
+
+ qemu_madvise(ptr, sz,
+ value ? QEMU_MADV_MERGEABLE : QEMU_MADV_UNMERGEABLE);
+ backend->merge = value;
+ }
+}
+
+static bool host_memory_backend_get_dump(Object *obj, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+
+ return backend->dump;
+}
+
+static void host_memory_backend_set_dump(Object *obj, bool value, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+
+ if (!memory_region_size(&backend->mr)) {
+ backend->dump = value;
+ return;
+ }
+
+ if (value != backend->dump) {
+ void *ptr = memory_region_get_ram_ptr(&backend->mr);
+ uint64_t sz = memory_region_size(&backend->mr);
+
+ qemu_madvise(ptr, sz,
+ value ? QEMU_MADV_DODUMP : QEMU_MADV_DONTDUMP);
+ backend->dump = value;
+ }
+}
+
+static bool host_memory_backend_get_prealloc(Object *obj, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+
+ return backend->prealloc || backend->force_prealloc;
+}
+
+static void host_memory_backend_set_prealloc(Object *obj, bool value,
+ Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+
+ if (backend->force_prealloc) {
+ if (value) {
+ error_setg(errp,
+ "remove -mem-prealloc to use the prealloc property");
+ return;
+ }
+ }
+
+ if (!memory_region_size(&backend->mr)) {
+ backend->prealloc = value;
+ return;
+ }
+
+ if (value && !backend->prealloc) {
+ int fd = memory_region_get_fd(&backend->mr);
+ void *ptr = memory_region_get_ram_ptr(&backend->mr);
+ uint64_t sz = memory_region_size(&backend->mr);
+
+ os_mem_prealloc(fd, ptr, sz);
+ backend->prealloc = true;
+ }
+}
+
+static void host_memory_backend_init(Object *obj)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+ MachineState *machine = MACHINE(qdev_get_machine());
+
+ backend->merge = machine_mem_merge(machine);
+ backend->dump = machine_dump_guest_core(machine);
+ backend->prealloc = mem_prealloc;
+
+ object_property_add_bool(obj, "merge",
+ host_memory_backend_get_merge,
+ host_memory_backend_set_merge, NULL);
+ object_property_add_bool(obj, "dump",
+ host_memory_backend_get_dump,
+ host_memory_backend_set_dump, NULL);
+ object_property_add_bool(obj, "prealloc",
+ host_memory_backend_get_prealloc,
+ host_memory_backend_set_prealloc, NULL);
+ object_property_add(obj, "size", "int",
+ host_memory_backend_get_size,
+ host_memory_backend_set_size, NULL, NULL, NULL);
+ object_property_add(obj, "host-nodes", "int",
+ host_memory_backend_get_host_nodes,
+ host_memory_backend_set_host_nodes, NULL, NULL, NULL);
+ object_property_add_enum(obj, "policy", "HostMemPolicy",
+ HostMemPolicy_lookup,
+ host_memory_backend_get_policy,
+ host_memory_backend_set_policy, NULL);
+}
+
+MemoryRegion *
+host_memory_backend_get_memory(HostMemoryBackend *backend, Error **errp)
+{
+ return memory_region_size(&backend->mr) ? &backend->mr : NULL;
+}
+
+static void
+host_memory_backend_memory_complete(UserCreatable *uc, Error **errp)
+{
+ HostMemoryBackend *backend = MEMORY_BACKEND(uc);
+ HostMemoryBackendClass *bc = MEMORY_BACKEND_GET_CLASS(uc);
+ Error *local_err = NULL;
+ void *ptr;
+ uint64_t sz;
+
+ if (bc->alloc) {
+ bc->alloc(backend, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ ptr = memory_region_get_ram_ptr(&backend->mr);
+ sz = memory_region_size(&backend->mr);
+
+ if (backend->merge) {
+ qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE);
+ }
+ if (!backend->dump) {
+ qemu_madvise(ptr, sz, QEMU_MADV_DONTDUMP);
+ }
+#ifdef CONFIG_NUMA
+ unsigned long lastbit = find_last_bit(backend->host_nodes, MAX_NODES);
+ /* lastbit == MAX_NODES means maxnode = 0 */
+ unsigned long maxnode = (lastbit + 1) % (MAX_NODES + 1);
+ /* ensure policy won't be ignored in case memory is preallocated
+ * before mbind(). note: MPOL_MF_STRICT is ignored on hugepages so
+ * this doesn't catch hugepage case. */
+ unsigned flags = MPOL_MF_STRICT | MPOL_MF_MOVE;
+
+ /* check for invalid host-nodes and policies and give more verbose
+ * error messages than mbind(). */
+ if (maxnode && backend->policy == MPOL_DEFAULT) {
+ error_setg(errp, "host-nodes must be empty for policy default,"
+ " or you should explicitly specify a policy other"
+ " than default");
+ return;
+ } else if (maxnode == 0 && backend->policy != MPOL_DEFAULT) {
+ error_setg(errp, "host-nodes must be set for policy %s",
+ HostMemPolicy_lookup[backend->policy]);
+ return;
+ }
+
+ /* We can have up to MAX_NODES nodes, but we need to pass maxnode+1
+ * as argument to mbind() due to an old Linux bug (feature?) which
+ * cuts off the last specified node. This means backend->host_nodes
+ * must have MAX_NODES+1 bits available.
+ */
+ assert(sizeof(backend->host_nodes) >=
+ BITS_TO_LONGS(MAX_NODES + 1) * sizeof(unsigned long));
+ assert(maxnode <= MAX_NODES);
+ if (mbind(ptr, sz, backend->policy,
+ maxnode ? backend->host_nodes : NULL, maxnode + 1, flags)) {
+ if (backend->policy != MPOL_DEFAULT || errno != ENOSYS) {
+ error_setg_errno(errp, errno,
+ "cannot bind memory to host NUMA nodes");
+ return;
+ }
+ }
+#endif
+ /* Preallocate memory after the NUMA policy has been instantiated.
+ * This is necessary to guarantee memory is allocated with
+ * specified NUMA policy in place.
+ */
+ if (backend->prealloc) {
+ os_mem_prealloc(memory_region_get_fd(&backend->mr), ptr, sz);
+ }
+ }
+}
+
+static bool
+host_memory_backend_can_be_deleted(UserCreatable *uc, Error **errp)
+{
+ MemoryRegion *mr;
+
+ mr = host_memory_backend_get_memory(MEMORY_BACKEND(uc), errp);
+ if (memory_region_is_mapped(mr)) {
+ return false;
+ } else {
+ return true;
+ }
+}
+
+static void
+host_memory_backend_class_init(ObjectClass *oc, void *data)
+{
+ UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
+
+ ucc->complete = host_memory_backend_memory_complete;
+ ucc->can_be_deleted = host_memory_backend_can_be_deleted;
+}
+
+static const TypeInfo host_memory_backend_info = {
+ .name = TYPE_MEMORY_BACKEND,
+ .parent = TYPE_OBJECT,
+ .abstract = true,
+ .class_size = sizeof(HostMemoryBackendClass),
+ .class_init = host_memory_backend_class_init,
+ .instance_size = sizeof(HostMemoryBackend),
+ .instance_init = host_memory_backend_init,
+ .interfaces = (InterfaceInfo[]) {
+ { TYPE_USER_CREATABLE },
+ { }
+ }
+};
+
+static void register_types(void)
+{
+ type_register_static(&host_memory_backend_info);
+}
+
+type_init(register_types);
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