qemu/hw/mem/pc-dimm.c
Xiao Guangrong 2aece63c8a hostmem: detect host backend memory is being used properly
Currently, we use memory_region_is_mapped() to detect if the host
backend memory is being used. This works if the memory is directly
mapped into guest's address space, however, it is not true for
nvdimm as it uses aliased memory region to map the memory. This is
why this bug can happen:
   https://bugzilla.redhat.com/show_bug.cgi?id=1352769

Fix it by introduce a new filed, is_mapped, to HostMemoryBackend,
we set/clear this filed accordingly when the device link/unlink to
host backend memory

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-13 13:30:04 +02:00

468 lines
14 KiB
C

/*
* Dimm device for Memory Hotplug
*
* Copyright ProfitBricks GmbH 2012
* Copyright (C) 2014 Red Hat Inc
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>
*/
#include "qemu/osdep.h"
#include "hw/mem/pc-dimm.h"
#include "qapi/error.h"
#include "qemu/config-file.h"
#include "qapi/visitor.h"
#include "qemu/range.h"
#include "sysemu/numa.h"
#include "sysemu/kvm.h"
#include "trace.h"
#include "hw/virtio/vhost.h"
typedef struct pc_dimms_capacity {
uint64_t size;
Error **errp;
} pc_dimms_capacity;
void pc_dimm_memory_plug(DeviceState *dev, MemoryHotplugState *hpms,
MemoryRegion *mr, uint64_t align, Error **errp)
{
int slot;
MachineState *machine = MACHINE(qdev_get_machine());
PCDIMMDevice *dimm = PC_DIMM(dev);
PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
MemoryRegion *vmstate_mr = ddc->get_vmstate_memory_region(dimm);
Error *local_err = NULL;
uint64_t existing_dimms_capacity = 0;
uint64_t addr;
addr = object_property_get_int(OBJECT(dimm), PC_DIMM_ADDR_PROP, &local_err);
if (local_err) {
goto out;
}
addr = pc_dimm_get_free_addr(hpms->base,
memory_region_size(&hpms->mr),
!addr ? NULL : &addr, align,
memory_region_size(mr), &local_err);
if (local_err) {
goto out;
}
existing_dimms_capacity = pc_existing_dimms_capacity(&local_err);
if (local_err) {
goto out;
}
if (existing_dimms_capacity + memory_region_size(mr) >
machine->maxram_size - machine->ram_size) {
error_setg(&local_err, "not enough space, currently 0x%" PRIx64
" in use of total hot pluggable 0x" RAM_ADDR_FMT,
existing_dimms_capacity,
machine->maxram_size - machine->ram_size);
goto out;
}
object_property_set_int(OBJECT(dev), addr, PC_DIMM_ADDR_PROP, &local_err);
if (local_err) {
goto out;
}
trace_mhp_pc_dimm_assigned_address(addr);
slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP, &local_err);
if (local_err) {
goto out;
}
slot = pc_dimm_get_free_slot(slot == PC_DIMM_UNASSIGNED_SLOT ? NULL : &slot,
machine->ram_slots, &local_err);
if (local_err) {
goto out;
}
object_property_set_int(OBJECT(dev), slot, PC_DIMM_SLOT_PROP, &local_err);
if (local_err) {
goto out;
}
trace_mhp_pc_dimm_assigned_slot(slot);
if (kvm_enabled() && !kvm_has_free_slot(machine)) {
error_setg(&local_err, "hypervisor has no free memory slots left");
goto out;
}
if (!vhost_has_free_slot()) {
error_setg(&local_err, "a used vhost backend has no free"
" memory slots left");
goto out;
}
memory_region_add_subregion(&hpms->mr, addr - hpms->base, mr);
vmstate_register_ram(vmstate_mr, dev);
numa_set_mem_node_id(addr, memory_region_size(mr), dimm->node);
out:
error_propagate(errp, local_err);
}
void pc_dimm_memory_unplug(DeviceState *dev, MemoryHotplugState *hpms,
MemoryRegion *mr)
{
PCDIMMDevice *dimm = PC_DIMM(dev);
PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
MemoryRegion *vmstate_mr = ddc->get_vmstate_memory_region(dimm);
numa_unset_mem_node_id(dimm->addr, memory_region_size(mr), dimm->node);
memory_region_del_subregion(&hpms->mr, mr);
vmstate_unregister_ram(vmstate_mr, dev);
}
static int pc_existing_dimms_capacity_internal(Object *obj, void *opaque)
{
pc_dimms_capacity *cap = opaque;
uint64_t *size = &cap->size;
if (object_dynamic_cast(obj, TYPE_PC_DIMM)) {
DeviceState *dev = DEVICE(obj);
if (dev->realized) {
(*size) += object_property_get_int(obj, PC_DIMM_SIZE_PROP,
cap->errp);
}
if (cap->errp && *cap->errp) {
return 1;
}
}
object_child_foreach(obj, pc_existing_dimms_capacity_internal, opaque);
return 0;
}
uint64_t pc_existing_dimms_capacity(Error **errp)
{
pc_dimms_capacity cap;
cap.size = 0;
cap.errp = errp;
pc_existing_dimms_capacity_internal(qdev_get_machine(), &cap);
return cap.size;
}
int qmp_pc_dimm_device_list(Object *obj, void *opaque)
{
MemoryDeviceInfoList ***prev = opaque;
if (object_dynamic_cast(obj, TYPE_PC_DIMM)) {
DeviceState *dev = DEVICE(obj);
if (dev->realized) {
MemoryDeviceInfoList *elem = g_new0(MemoryDeviceInfoList, 1);
MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1);
PCDIMMDeviceInfo *di = g_new0(PCDIMMDeviceInfo, 1);
DeviceClass *dc = DEVICE_GET_CLASS(obj);
PCDIMMDevice *dimm = PC_DIMM(obj);
if (dev->id) {
di->has_id = true;
di->id = g_strdup(dev->id);
}
di->hotplugged = dev->hotplugged;
di->hotpluggable = dc->hotpluggable;
di->addr = dimm->addr;
di->slot = dimm->slot;
di->node = dimm->node;
di->size = object_property_get_int(OBJECT(dimm), PC_DIMM_SIZE_PROP,
NULL);
di->memdev = object_get_canonical_path(OBJECT(dimm->hostmem));
info->u.dimm.data = di;
elem->value = info;
elem->next = NULL;
**prev = elem;
*prev = &elem->next;
}
}
object_child_foreach(obj, qmp_pc_dimm_device_list, opaque);
return 0;
}
static int pc_dimm_slot2bitmap(Object *obj, void *opaque)
{
unsigned long *bitmap = opaque;
if (object_dynamic_cast(obj, TYPE_PC_DIMM)) {
DeviceState *dev = DEVICE(obj);
if (dev->realized) { /* count only realized DIMMs */
PCDIMMDevice *d = PC_DIMM(obj);
set_bit(d->slot, bitmap);
}
}
object_child_foreach(obj, pc_dimm_slot2bitmap, opaque);
return 0;
}
int pc_dimm_get_free_slot(const int *hint, int max_slots, Error **errp)
{
unsigned long *bitmap = bitmap_new(max_slots);
int slot = 0;
object_child_foreach(qdev_get_machine(), pc_dimm_slot2bitmap, bitmap);
/* check if requested slot is not occupied */
if (hint) {
if (*hint >= max_slots) {
error_setg(errp, "invalid slot# %d, should be less than %d",
*hint, max_slots);
} else if (!test_bit(*hint, bitmap)) {
slot = *hint;
} else {
error_setg(errp, "slot %d is busy", *hint);
}
goto out;
}
/* search for free slot */
slot = find_first_zero_bit(bitmap, max_slots);
if (slot == max_slots) {
error_setg(errp, "no free slots available");
}
out:
g_free(bitmap);
return slot;
}
static gint pc_dimm_addr_sort(gconstpointer a, gconstpointer b)
{
PCDIMMDevice *x = PC_DIMM(a);
PCDIMMDevice *y = PC_DIMM(b);
Int128 diff = int128_sub(int128_make64(x->addr), int128_make64(y->addr));
if (int128_lt(diff, int128_zero())) {
return -1;
} else if (int128_gt(diff, int128_zero())) {
return 1;
}
return 0;
}
static int pc_dimm_built_list(Object *obj, void *opaque)
{
GSList **list = opaque;
if (object_dynamic_cast(obj, TYPE_PC_DIMM)) {
DeviceState *dev = DEVICE(obj);
if (dev->realized) { /* only realized DIMMs matter */
*list = g_slist_insert_sorted(*list, dev, pc_dimm_addr_sort);
}
}
object_child_foreach(obj, pc_dimm_built_list, opaque);
return 0;
}
uint64_t pc_dimm_get_free_addr(uint64_t address_space_start,
uint64_t address_space_size,
uint64_t *hint, uint64_t align, uint64_t size,
Error **errp)
{
GSList *list = NULL, *item;
uint64_t new_addr, ret = 0;
uint64_t address_space_end = address_space_start + address_space_size;
g_assert(QEMU_ALIGN_UP(address_space_start, align) == address_space_start);
if (!address_space_size) {
error_setg(errp, "memory hotplug is not enabled, "
"please add maxmem option");
goto out;
}
if (hint && QEMU_ALIGN_UP(*hint, align) != *hint) {
error_setg(errp, "address must be aligned to 0x%" PRIx64 " bytes",
align);
goto out;
}
if (QEMU_ALIGN_UP(size, align) != size) {
error_setg(errp, "backend memory size must be multiple of 0x%"
PRIx64, align);
goto out;
}
assert(address_space_end > address_space_start);
object_child_foreach(qdev_get_machine(), pc_dimm_built_list, &list);
if (hint) {
new_addr = *hint;
} else {
new_addr = address_space_start;
}
/* find address range that will fit new DIMM */
for (item = list; item; item = g_slist_next(item)) {
PCDIMMDevice *dimm = item->data;
uint64_t dimm_size = object_property_get_int(OBJECT(dimm),
PC_DIMM_SIZE_PROP,
errp);
if (errp && *errp) {
goto out;
}
if (ranges_overlap(dimm->addr, dimm_size, new_addr, size)) {
if (hint) {
DeviceState *d = DEVICE(dimm);
error_setg(errp, "address range conflicts with '%s'", d->id);
goto out;
}
new_addr = QEMU_ALIGN_UP(dimm->addr + dimm_size, align);
}
}
ret = new_addr;
if (new_addr < address_space_start) {
error_setg(errp, "can't add memory [0x%" PRIx64 ":0x%" PRIx64
"] at 0x%" PRIx64, new_addr, size, address_space_start);
} else if ((new_addr + size) > address_space_end) {
error_setg(errp, "can't add memory [0x%" PRIx64 ":0x%" PRIx64
"] beyond 0x%" PRIx64, new_addr, size, address_space_end);
}
out:
g_slist_free(list);
return ret;
}
static Property pc_dimm_properties[] = {
DEFINE_PROP_UINT64(PC_DIMM_ADDR_PROP, PCDIMMDevice, addr, 0),
DEFINE_PROP_UINT32(PC_DIMM_NODE_PROP, PCDIMMDevice, node, 0),
DEFINE_PROP_INT32(PC_DIMM_SLOT_PROP, PCDIMMDevice, slot,
PC_DIMM_UNASSIGNED_SLOT),
DEFINE_PROP_END_OF_LIST(),
};
static void pc_dimm_get_size(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
int64_t value;
MemoryRegion *mr;
PCDIMMDevice *dimm = PC_DIMM(obj);
PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(obj);
mr = ddc->get_memory_region(dimm);
value = memory_region_size(mr);
visit_type_int(v, name, &value, errp);
}
static void pc_dimm_check_memdev_is_busy(Object *obj, const char *name,
Object *val, Error **errp)
{
Error *local_err = NULL;
if (host_memory_backend_is_mapped(MEMORY_BACKEND(val))) {
char *path = object_get_canonical_path_component(val);
error_setg(&local_err, "can't use already busy memdev: %s", path);
g_free(path);
} else {
qdev_prop_allow_set_link_before_realize(obj, name, val, &local_err);
}
error_propagate(errp, local_err);
}
static void pc_dimm_init(Object *obj)
{
PCDIMMDevice *dimm = PC_DIMM(obj);
object_property_add(obj, PC_DIMM_SIZE_PROP, "int", pc_dimm_get_size,
NULL, NULL, NULL, &error_abort);
object_property_add_link(obj, PC_DIMM_MEMDEV_PROP, TYPE_MEMORY_BACKEND,
(Object **)&dimm->hostmem,
pc_dimm_check_memdev_is_busy,
OBJ_PROP_LINK_UNREF_ON_RELEASE,
&error_abort);
}
static void pc_dimm_realize(DeviceState *dev, Error **errp)
{
PCDIMMDevice *dimm = PC_DIMM(dev);
PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
if (!dimm->hostmem) {
error_setg(errp, "'" PC_DIMM_MEMDEV_PROP "' property is not set");
return;
}
if (((nb_numa_nodes > 0) && (dimm->node >= nb_numa_nodes)) ||
(!nb_numa_nodes && dimm->node)) {
error_setg(errp, "'DIMM property " PC_DIMM_NODE_PROP " has value %"
PRIu32 "' which exceeds the number of numa nodes: %d",
dimm->node, nb_numa_nodes ? nb_numa_nodes : 1);
return;
}
if (ddc->realize) {
ddc->realize(dimm, errp);
}
host_memory_backend_set_mapped(dimm->hostmem, true);
}
static void pc_dimm_unrealize(DeviceState *dev, Error **errp)
{
PCDIMMDevice *dimm = PC_DIMM(dev);
host_memory_backend_set_mapped(dimm->hostmem, false);
}
static MemoryRegion *pc_dimm_get_memory_region(PCDIMMDevice *dimm)
{
return host_memory_backend_get_memory(dimm->hostmem, &error_abort);
}
static MemoryRegion *pc_dimm_get_vmstate_memory_region(PCDIMMDevice *dimm)
{
return host_memory_backend_get_memory(dimm->hostmem, &error_abort);
}
static void pc_dimm_class_init(ObjectClass *oc, void *data)
{
DeviceClass *dc = DEVICE_CLASS(oc);
PCDIMMDeviceClass *ddc = PC_DIMM_CLASS(oc);
dc->realize = pc_dimm_realize;
dc->unrealize = pc_dimm_unrealize;
dc->props = pc_dimm_properties;
dc->desc = "DIMM memory module";
ddc->get_memory_region = pc_dimm_get_memory_region;
ddc->get_vmstate_memory_region = pc_dimm_get_vmstate_memory_region;
}
static TypeInfo pc_dimm_info = {
.name = TYPE_PC_DIMM,
.parent = TYPE_DEVICE,
.instance_size = sizeof(PCDIMMDevice),
.instance_init = pc_dimm_init,
.class_init = pc_dimm_class_init,
.class_size = sizeof(PCDIMMDeviceClass),
};
static void pc_dimm_register_types(void)
{
type_register_static(&pc_dimm_info);
}
type_init(pc_dimm_register_types)