qemu/backends/hostmem.c
Zhang Yi 21d1683690 hostmem: add more information in error messages
When there are multiple memory backends in use, including the object type
and property name in the error message can help users to locate the error.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com>
Message-Id: <97d9193875747d8378c05b9e3b3cb39c1b7d2b4e.1546399191.git.yi.z.zhang@linux.intel.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
[ehabkost: reword commit message]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-01-28 15:52:05 -02:00

504 lines
15 KiB
C

/*
* 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 "qemu/osdep.h"
#include "sysemu/hostmem.h"
#include "hw/boards.h"
#include "qapi/error.h"
#include "qapi/qapi-builtin-visit.h"
#include "qapi/visitor.h"
#include "qemu/config-file.h"
#include "qom/object_interfaces.h"
#include "qemu/mmap-alloc.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
char *
host_memory_backend_get_name(HostMemoryBackend *backend)
{
if (!backend->use_canonical_path) {
return object_get_canonical_path_component(OBJECT(backend));
}
return object_get_canonical_path(OBJECT(backend));
}
static void
host_memory_backend_get_size(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
uint64_t value = backend->size;
visit_type_size(v, name, &value, errp);
}
static void
host_memory_backend_set_size(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
Error *local_err = NULL;
uint64_t value;
if (host_memory_backend_mr_inited(backend)) {
error_setg(&local_err, "cannot change property %s of %s ",
name, object_get_typename(obj));
goto out;
}
visit_type_size(v, name, &value, &local_err);
if (local_err) {
goto out;
}
if (!value) {
error_setg(&local_err,
"property '%s' of %s doesn't take value '%" PRIu64 "'",
name, object_get_typename(obj), value);
goto out;
}
backend->size = value;
out:
error_propagate(errp, local_err);
}
static void
host_memory_backend_get_host_nodes(Object *obj, Visitor *v, const char *name,
void *opaque, 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, name, &host_nodes, errp);
}
static void
host_memory_backend_set_host_nodes(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
#ifdef CONFIG_NUMA
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
uint16List *l, *host_nodes = NULL;
visit_type_uint16List(v, name, &host_nodes, errp);
for (l = host_nodes; l; l = l->next) {
if (l->value >= MAX_NODES) {
error_setg(errp, "Invalid host-nodes value: %d", l->value);
goto out;
}
}
for (l = host_nodes; l; l = l->next) {
bitmap_set(backend->host_nodes, l->value, 1);
}
out:
qapi_free_uint16List(host_nodes);
#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 (!host_memory_backend_mr_inited(backend)) {
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 (!host_memory_backend_mr_inited(backend)) {
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)
{
Error *local_err = NULL;
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
if (backend->force_prealloc) {
if (value) {
error_setg(errp,
"remove -mem-prealloc to use the prealloc property");
return;
}
}
if (!host_memory_backend_mr_inited(backend)) {
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, smp_cpus, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
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;
}
static void host_memory_backend_post_init(Object *obj)
{
object_apply_compat_props(obj);
}
bool host_memory_backend_mr_inited(HostMemoryBackend *backend)
{
/*
* NOTE: We forbid zero-length memory backend, so here zero means
* "we haven't inited the backend memory region yet".
*/
return memory_region_size(&backend->mr) != 0;
}
MemoryRegion *host_memory_backend_get_memory(HostMemoryBackend *backend)
{
return host_memory_backend_mr_inited(backend) ? &backend->mr : NULL;
}
void host_memory_backend_set_mapped(HostMemoryBackend *backend, bool mapped)
{
backend->is_mapped = mapped;
}
bool host_memory_backend_is_mapped(HostMemoryBackend *backend)
{
return backend->is_mapped;
}
#ifdef __linux__
size_t host_memory_backend_pagesize(HostMemoryBackend *memdev)
{
Object *obj = OBJECT(memdev);
char *path = object_property_get_str(obj, "mem-path", NULL);
size_t pagesize = qemu_mempath_getpagesize(path);
g_free(path);
return pagesize;
}
#else
size_t host_memory_backend_pagesize(HostMemoryBackend *memdev)
{
return getpagesize();
}
#endif
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) {
goto out;
}
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_str(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,
smp_cpus, &local_err);
if (local_err) {
goto out;
}
}
}
out:
error_propagate(errp, local_err);
}
static bool
host_memory_backend_can_be_deleted(UserCreatable *uc)
{
if (host_memory_backend_is_mapped(MEMORY_BACKEND(uc))) {
return false;
} else {
return true;
}
}
static bool host_memory_backend_get_share(Object *o, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(o);
return backend->share;
}
static void host_memory_backend_set_share(Object *o, bool value, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(o);
if (host_memory_backend_mr_inited(backend)) {
error_setg(errp, "cannot change property value");
return;
}
backend->share = value;
}
static bool
host_memory_backend_get_use_canonical_path(Object *obj, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
return backend->use_canonical_path;
}
static void
host_memory_backend_set_use_canonical_path(Object *obj, bool value,
Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
backend->use_canonical_path = value;
}
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;
object_class_property_add_bool(oc, "merge",
host_memory_backend_get_merge,
host_memory_backend_set_merge, &error_abort);
object_class_property_set_description(oc, "merge",
"Mark memory as mergeable", &error_abort);
object_class_property_add_bool(oc, "dump",
host_memory_backend_get_dump,
host_memory_backend_set_dump, &error_abort);
object_class_property_set_description(oc, "dump",
"Set to 'off' to exclude from core dump", &error_abort);
object_class_property_add_bool(oc, "prealloc",
host_memory_backend_get_prealloc,
host_memory_backend_set_prealloc, &error_abort);
object_class_property_set_description(oc, "prealloc",
"Preallocate memory", &error_abort);
object_class_property_add(oc, "size", "int",
host_memory_backend_get_size,
host_memory_backend_set_size,
NULL, NULL, &error_abort);
object_class_property_set_description(oc, "size",
"Size of the memory region (ex: 500M)", &error_abort);
object_class_property_add(oc, "host-nodes", "int",
host_memory_backend_get_host_nodes,
host_memory_backend_set_host_nodes,
NULL, NULL, &error_abort);
object_class_property_set_description(oc, "host-nodes",
"Binds memory to the list of NUMA host nodes", &error_abort);
object_class_property_add_enum(oc, "policy", "HostMemPolicy",
&HostMemPolicy_lookup,
host_memory_backend_get_policy,
host_memory_backend_set_policy, &error_abort);
object_class_property_set_description(oc, "policy",
"Set the NUMA policy", &error_abort);
object_class_property_add_bool(oc, "share",
host_memory_backend_get_share, host_memory_backend_set_share,
&error_abort);
object_class_property_set_description(oc, "share",
"Mark the memory as private to QEMU or shared", &error_abort);
object_class_property_add_bool(oc, "x-use-canonical-path-for-ramblock-id",
host_memory_backend_get_use_canonical_path,
host_memory_backend_set_use_canonical_path, &error_abort);
}
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,
.instance_post_init = host_memory_backend_post_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_USER_CREATABLE },
{ }
}
};
static void register_types(void)
{
type_register_static(&host_memory_backend_info);
}
type_init(register_types);