aboutsummaryrefslogtreecommitdiff
path: root/hw/virtio
diff options
context:
space:
mode:
Diffstat (limited to 'hw/virtio')
-rw-r--r--hw/virtio/trace-events6
-rw-r--r--hw/virtio/vhost-backend.c4
-rw-r--r--hw/virtio/vhost.c8
-rw-r--r--hw/virtio/virtio-iommu.c205
-rw-r--r--hw/virtio/virtio-mem-pci.c7
-rw-r--r--hw/virtio/virtio-mem.c113
6 files changed, 332 insertions, 11 deletions
diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index cf1e59d..2060a14 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -106,6 +106,12 @@ virtio_iommu_put_domain(uint32_t domain_id) "Free domain=%d"
virtio_iommu_translate_out(uint64_t virt_addr, uint64_t phys_addr, uint32_t sid) "0x%"PRIx64" -> 0x%"PRIx64 " for sid=%d"
virtio_iommu_report_fault(uint8_t reason, uint32_t flags, uint32_t endpoint, uint64_t addr) "FAULT reason=%d flags=%d endpoint=%d address =0x%"PRIx64
virtio_iommu_fill_resv_property(uint32_t devid, uint8_t subtype, uint64_t start, uint64_t end) "dev= %d, type=%d start=0x%"PRIx64" end=0x%"PRIx64
+virtio_iommu_notify_map(const char *name, uint64_t virt_start, uint64_t virt_end, uint64_t phys_start, uint32_t flags) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64" phys_start=0x%"PRIx64" flags=%d"
+virtio_iommu_notify_unmap(const char *name, uint64_t virt_start, uint64_t virt_end) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64
+virtio_iommu_remap(const char *name, uint64_t virt_start, uint64_t virt_end, uint64_t phys_start) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64" phys_start=0x%"PRIx64
+virtio_iommu_set_page_size_mask(const char *name, uint64_t old, uint64_t new) "mr=%s old_mask=0x%"PRIx64" new_mask=0x%"PRIx64
+virtio_iommu_notify_flag_add(const char *name) "add notifier to mr %s"
+virtio_iommu_notify_flag_del(const char *name) "del notifier from mr %s"
# virtio-mem.c
virtio_mem_send_response(uint16_t type) "type=%" PRIu16
diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c
index 88c8ecc..222bbcc 100644
--- a/hw/virtio/vhost-backend.c
+++ b/hw/virtio/vhost-backend.c
@@ -257,7 +257,7 @@ static int vhost_kernel_send_device_iotlb_msg(struct vhost_dev *dev,
struct vhost_iotlb_msg *imsg)
{
if (dev->backend_cap & (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) {
- struct vhost_msg_v2 msg;
+ struct vhost_msg_v2 msg = {};
msg.type = VHOST_IOTLB_MSG_V2;
msg.iotlb = *imsg;
@@ -267,7 +267,7 @@ static int vhost_kernel_send_device_iotlb_msg(struct vhost_dev *dev,
return -EFAULT;
}
} else {
- struct vhost_msg msg;
+ struct vhost_msg msg = {};
msg.type = VHOST_IOTLB_MSG;
msg.iotlb = *imsg;
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index f248237..614ccc2 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -1645,15 +1645,17 @@ int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f)
return 0;
}
-int vhost_dev_prepare_inflight(struct vhost_dev *hdev)
+int vhost_dev_prepare_inflight(struct vhost_dev *hdev, VirtIODevice *vdev)
{
int r;
-
+
if (hdev->vhost_ops->vhost_get_inflight_fd == NULL ||
hdev->vhost_ops->vhost_set_inflight_fd == NULL) {
return 0;
}
-
+
+ hdev->vdev = vdev;
+
r = vhost_dev_set_features(hdev, hdev->log_enabled);
if (r < 0) {
VHOST_OPS_DEBUG("vhost_dev_prepare_inflight failed");
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 21ec63b..fc5c75d 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -49,6 +49,7 @@ typedef struct VirtIOIOMMUDomain {
typedef struct VirtIOIOMMUEndpoint {
uint32_t id;
VirtIOIOMMUDomain *domain;
+ IOMMUMemoryRegion *iommu_mr;
QLIST_ENTRY(VirtIOIOMMUEndpoint) next;
} VirtIOIOMMUEndpoint;
@@ -101,7 +102,7 @@ static IOMMUMemoryRegion *virtio_iommu_mr(VirtIOIOMMU *s, uint32_t sid)
bus_n = PCI_BUS_NUM(sid);
iommu_pci_bus = iommu_find_iommu_pcibus(s, bus_n);
if (iommu_pci_bus) {
- devfn = sid & PCI_DEVFN_MAX;
+ devfn = sid & (PCI_DEVFN_MAX - 1);
dev = iommu_pci_bus->pbdev[devfn];
if (dev) {
return &dev->iommu_mr;
@@ -124,11 +125,84 @@ static gint interval_cmp(gconstpointer a, gconstpointer b, gpointer user_data)
}
}
+static void virtio_iommu_notify_map(IOMMUMemoryRegion *mr, hwaddr virt_start,
+ hwaddr virt_end, hwaddr paddr,
+ uint32_t flags)
+{
+ IOMMUTLBEntry entry;
+ IOMMUAccessFlags perm = IOMMU_ACCESS_FLAG(flags & VIRTIO_IOMMU_MAP_F_READ,
+ flags & VIRTIO_IOMMU_MAP_F_WRITE);
+
+ if (!(mr->iommu_notify_flags & IOMMU_NOTIFIER_MAP) ||
+ (flags & VIRTIO_IOMMU_MAP_F_MMIO) || !perm) {
+ return;
+ }
+
+ trace_virtio_iommu_notify_map(mr->parent_obj.name, virt_start, virt_end,
+ paddr, perm);
+
+ entry.target_as = &address_space_memory;
+ entry.addr_mask = virt_end - virt_start;
+ entry.iova = virt_start;
+ entry.perm = perm;
+ entry.translated_addr = paddr;
+
+ memory_region_notify_iommu(mr, 0, entry);
+}
+
+static void virtio_iommu_notify_unmap(IOMMUMemoryRegion *mr, hwaddr virt_start,
+ hwaddr virt_end)
+{
+ IOMMUTLBEntry entry;
+
+ if (!(mr->iommu_notify_flags & IOMMU_NOTIFIER_UNMAP)) {
+ return;
+ }
+
+ trace_virtio_iommu_notify_unmap(mr->parent_obj.name, virt_start, virt_end);
+
+ entry.target_as = &address_space_memory;
+ entry.addr_mask = virt_end - virt_start;
+ entry.iova = virt_start;
+ entry.perm = IOMMU_NONE;
+ entry.translated_addr = 0;
+
+ memory_region_notify_iommu(mr, 0, entry);
+}
+
+static gboolean virtio_iommu_notify_unmap_cb(gpointer key, gpointer value,
+ gpointer data)
+{
+ VirtIOIOMMUInterval *interval = (VirtIOIOMMUInterval *) key;
+ IOMMUMemoryRegion *mr = (IOMMUMemoryRegion *) data;
+
+ virtio_iommu_notify_unmap(mr, interval->low, interval->high);
+
+ return false;
+}
+
+static gboolean virtio_iommu_notify_map_cb(gpointer key, gpointer value,
+ gpointer data)
+{
+ VirtIOIOMMUMapping *mapping = (VirtIOIOMMUMapping *) value;
+ VirtIOIOMMUInterval *interval = (VirtIOIOMMUInterval *) key;
+ IOMMUMemoryRegion *mr = (IOMMUMemoryRegion *) data;
+
+ virtio_iommu_notify_map(mr, interval->low, interval->high,
+ mapping->phys_addr, mapping->flags);
+
+ return false;
+}
+
static void virtio_iommu_detach_endpoint_from_domain(VirtIOIOMMUEndpoint *ep)
{
+ VirtIOIOMMUDomain *domain = ep->domain;
+
if (!ep->domain) {
return;
}
+ g_tree_foreach(domain->mappings, virtio_iommu_notify_unmap_cb,
+ ep->iommu_mr);
QLIST_REMOVE(ep, next);
ep->domain = NULL;
}
@@ -137,16 +211,19 @@ static VirtIOIOMMUEndpoint *virtio_iommu_get_endpoint(VirtIOIOMMU *s,
uint32_t ep_id)
{
VirtIOIOMMUEndpoint *ep;
+ IOMMUMemoryRegion *mr;
ep = g_tree_lookup(s->endpoints, GUINT_TO_POINTER(ep_id));
if (ep) {
return ep;
}
- if (!virtio_iommu_mr(s, ep_id)) {
+ mr = virtio_iommu_mr(s, ep_id);
+ if (!mr) {
return NULL;
}
ep = g_malloc0(sizeof(*ep));
ep->id = ep_id;
+ ep->iommu_mr = mr;
trace_virtio_iommu_get_endpoint(ep_id);
g_tree_insert(s->endpoints, GUINT_TO_POINTER(ep_id), ep);
return ep;
@@ -268,6 +345,10 @@ static int virtio_iommu_attach(VirtIOIOMMU *s,
ep->domain = domain;
+ /* Replay domain mappings on the associated memory region */
+ g_tree_foreach(domain->mappings, virtio_iommu_notify_map_cb,
+ ep->iommu_mr);
+
return VIRTIO_IOMMU_S_OK;
}
@@ -311,6 +392,7 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
VirtIOIOMMUDomain *domain;
VirtIOIOMMUInterval *interval;
VirtIOIOMMUMapping *mapping;
+ VirtIOIOMMUEndpoint *ep;
if (flags & ~VIRTIO_IOMMU_MAP_F_MASK) {
return VIRTIO_IOMMU_S_INVAL;
@@ -340,6 +422,11 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
g_tree_insert(domain->mappings, interval, mapping);
+ QLIST_FOREACH(ep, &domain->endpoint_list, next) {
+ virtio_iommu_notify_map(ep->iommu_mr, virt_start, virt_end, phys_start,
+ flags);
+ }
+
return VIRTIO_IOMMU_S_OK;
}
@@ -352,6 +439,7 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
VirtIOIOMMUMapping *iter_val;
VirtIOIOMMUInterval interval, *iter_key;
VirtIOIOMMUDomain *domain;
+ VirtIOIOMMUEndpoint *ep;
int ret = VIRTIO_IOMMU_S_OK;
trace_virtio_iommu_unmap(domain_id, virt_start, virt_end);
@@ -369,6 +457,10 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
uint64_t current_high = iter_key->high;
if (interval.low <= current_low && interval.high >= current_high) {
+ QLIST_FOREACH(ep, &domain->endpoint_list, next) {
+ virtio_iommu_notify_unmap(ep->iommu_mr, current_low,
+ current_high);
+ }
g_tree_remove(domain->mappings, iter_key);
trace_virtio_iommu_unmap_done(domain_id, current_low, current_high);
} else {
@@ -755,6 +847,107 @@ static gint int_cmp(gconstpointer a, gconstpointer b, gpointer user_data)
return (ua > ub) - (ua < ub);
}
+static gboolean virtio_iommu_remap(gpointer key, gpointer value, gpointer data)
+{
+ VirtIOIOMMUMapping *mapping = (VirtIOIOMMUMapping *) value;
+ VirtIOIOMMUInterval *interval = (VirtIOIOMMUInterval *) key;
+ IOMMUMemoryRegion *mr = (IOMMUMemoryRegion *) data;
+
+ trace_virtio_iommu_remap(mr->parent_obj.name, interval->low, interval->high,
+ mapping->phys_addr);
+ virtio_iommu_notify_map(mr, interval->low, interval->high,
+ mapping->phys_addr, mapping->flags);
+ return false;
+}
+
+static void virtio_iommu_replay(IOMMUMemoryRegion *mr, IOMMUNotifier *n)
+{
+ IOMMUDevice *sdev = container_of(mr, IOMMUDevice, iommu_mr);
+ VirtIOIOMMU *s = sdev->viommu;
+ uint32_t sid;
+ VirtIOIOMMUEndpoint *ep;
+
+ sid = virtio_iommu_get_bdf(sdev);
+
+ qemu_mutex_lock(&s->mutex);
+
+ if (!s->endpoints) {
+ goto unlock;
+ }
+
+ ep = g_tree_lookup(s->endpoints, GUINT_TO_POINTER(sid));
+ if (!ep || !ep->domain) {
+ goto unlock;
+ }
+
+ g_tree_foreach(ep->domain->mappings, virtio_iommu_remap, mr);
+
+unlock:
+ qemu_mutex_unlock(&s->mutex);
+}
+
+static int virtio_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu_mr,
+ IOMMUNotifierFlag old,
+ IOMMUNotifierFlag new,
+ Error **errp)
+{
+ if (old == IOMMU_NOTIFIER_NONE) {
+ trace_virtio_iommu_notify_flag_add(iommu_mr->parent_obj.name);
+ } else if (new == IOMMU_NOTIFIER_NONE) {
+ trace_virtio_iommu_notify_flag_del(iommu_mr->parent_obj.name);
+ }
+ return 0;
+}
+
+/*
+ * The default mask (TARGET_PAGE_MASK) is the smallest supported guest granule,
+ * for example 0xfffffffffffff000. When an assigned device has page size
+ * restrictions due to the hardware IOMMU configuration, apply this restriction
+ * to the mask.
+ */
+static int virtio_iommu_set_page_size_mask(IOMMUMemoryRegion *mr,
+ uint64_t new_mask,
+ Error **errp)
+{
+ IOMMUDevice *sdev = container_of(mr, IOMMUDevice, iommu_mr);
+ VirtIOIOMMU *s = sdev->viommu;
+ uint64_t cur_mask = s->config.page_size_mask;
+
+ trace_virtio_iommu_set_page_size_mask(mr->parent_obj.name, cur_mask,
+ new_mask);
+
+ if ((cur_mask & new_mask) == 0) {
+ error_setg(errp, "virtio-iommu page mask 0x%"PRIx64
+ " is incompatible with mask 0x%"PRIx64, cur_mask, new_mask);
+ return -1;
+ }
+
+ /*
+ * After the machine is finalized, we can't change the mask anymore. If by
+ * chance the hotplugged device supports the same granule, we can still
+ * accept it. Having a different masks is possible but the guest will use
+ * sub-optimal block sizes, so warn about it.
+ */
+ if (qdev_hotplug) {
+ int new_granule = ctz64(new_mask);
+ int cur_granule = ctz64(cur_mask);
+
+ if (new_granule != cur_granule) {
+ error_setg(errp, "virtio-iommu page mask 0x%"PRIx64
+ " is incompatible with mask 0x%"PRIx64, cur_mask,
+ new_mask);
+ return -1;
+ } else if (new_mask != cur_mask) {
+ warn_report("virtio-iommu page mask 0x%"PRIx64
+ " does not match 0x%"PRIx64, cur_mask, new_mask);
+ }
+ return 0;
+ }
+
+ s->config.page_size_mask &= new_mask;
+ return 0;
+}
+
static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
{
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
@@ -910,9 +1103,14 @@ static gboolean reconstruct_endpoints(gpointer key, gpointer value,
VirtIOIOMMU *s = (VirtIOIOMMU *)data;
VirtIOIOMMUDomain *d = (VirtIOIOMMUDomain *)value;
VirtIOIOMMUEndpoint *iter;
+ IOMMUMemoryRegion *mr;
QLIST_FOREACH(iter, &d->endpoint_list, next) {
+ mr = virtio_iommu_mr(s, iter->id);
+ assert(mr);
+
iter->domain = d;
+ iter->iommu_mr = mr;
g_tree_insert(s->endpoints, GUINT_TO_POINTER(iter->id), iter);
}
return false; /* continue the domain traversal */
@@ -979,6 +1177,9 @@ static void virtio_iommu_memory_region_class_init(ObjectClass *klass,
IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_CLASS(klass);
imrc->translate = virtio_iommu_translate;
+ imrc->replay = virtio_iommu_replay;
+ imrc->notify_flag_changed = virtio_iommu_notify_flag_changed;
+ imrc->iommu_set_page_size_mask = virtio_iommu_set_page_size_mask;
}
static const TypeInfo virtio_iommu_info = {
diff --git a/hw/virtio/virtio-mem-pci.c b/hw/virtio/virtio-mem-pci.c
index 913f4a3..fa5395c 100644
--- a/hw/virtio/virtio-mem-pci.c
+++ b/hw/virtio/virtio-mem-pci.c
@@ -76,6 +76,12 @@ static void virtio_mem_pci_fill_device_info(const MemoryDeviceState *md,
info->type = MEMORY_DEVICE_INFO_KIND_VIRTIO_MEM;
}
+static uint64_t virtio_mem_pci_get_min_alignment(const MemoryDeviceState *md)
+{
+ return object_property_get_uint(OBJECT(md), VIRTIO_MEM_BLOCK_SIZE_PROP,
+ &error_abort);
+}
+
static void virtio_mem_pci_size_change_notify(Notifier *notifier, void *data)
{
VirtIOMEMPCI *pci_mem = container_of(notifier, VirtIOMEMPCI,
@@ -110,6 +116,7 @@ static void virtio_mem_pci_class_init(ObjectClass *klass, void *data)
mdc->get_plugged_size = virtio_mem_pci_get_plugged_size;
mdc->get_memory_region = virtio_mem_pci_get_memory_region;
mdc->fill_device_info = virtio_mem_pci_fill_device_info;
+ mdc->get_min_alignment = virtio_mem_pci_get_min_alignment;
}
static void virtio_mem_pci_instance_init(Object *obj)
diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c
index 7c8ca9f..655824f 100644
--- a/hw/virtio/virtio-mem.c
+++ b/hw/virtio/virtio-mem.c
@@ -33,10 +33,83 @@
#include "trace.h"
/*
- * Use QEMU_VMALLOC_ALIGN, so no THP will have to be split when unplugging
- * memory (e.g., 2MB on x86_64).
+ * Let's not allow blocks smaller than 1 MiB, for example, to keep the tracking
+ * bitmap small.
*/
-#define VIRTIO_MEM_MIN_BLOCK_SIZE ((uint32_t)QEMU_VMALLOC_ALIGN)
+#define VIRTIO_MEM_MIN_BLOCK_SIZE ((uint32_t)(1 * MiB))
+
+#if defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) || \
+ defined(__powerpc64__)
+#define VIRTIO_MEM_DEFAULT_THP_SIZE ((uint32_t)(2 * MiB))
+#else
+ /* fallback to 1 MiB (e.g., the THP size on s390x) */
+#define VIRTIO_MEM_DEFAULT_THP_SIZE VIRTIO_MEM_MIN_BLOCK_SIZE
+#endif
+
+/*
+ * We want to have a reasonable default block size such that
+ * 1. We avoid splitting THPs when unplugging memory, which degrades
+ * performance.
+ * 2. We avoid placing THPs for plugged blocks that also cover unplugged
+ * blocks.
+ *
+ * The actual THP size might differ between Linux kernels, so we try to probe
+ * it. In the future (if we ever run into issues regarding 2.), we might want
+ * to disable THP in case we fail to properly probe the THP size, or if the
+ * block size is configured smaller than the THP size.
+ */
+static uint32_t thp_size;
+
+#define HPAGE_PMD_SIZE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size"
+static uint32_t virtio_mem_thp_size(void)
+{
+ gchar *content = NULL;
+ const char *endptr;
+ uint64_t tmp;
+
+ if (thp_size) {
+ return thp_size;
+ }
+
+ /*
+ * Try to probe the actual THP size, fallback to (sane but eventually
+ * incorrect) default sizes.
+ */
+ if (g_file_get_contents(HPAGE_PMD_SIZE_PATH, &content, NULL, NULL) &&
+ !qemu_strtou64(content, &endptr, 0, &tmp) &&
+ (!endptr || *endptr == '\n')) {
+ /*
+ * Sanity-check the value, if it's too big (e.g., aarch64 with 64k base
+ * pages) or weird, fallback to something smaller.
+ */
+ if (!tmp || !is_power_of_2(tmp) || tmp > 16 * MiB) {
+ warn_report("Read unsupported THP size: %" PRIx64, tmp);
+ } else {
+ thp_size = tmp;
+ }
+ }
+
+ if (!thp_size) {
+ thp_size = VIRTIO_MEM_DEFAULT_THP_SIZE;
+ warn_report("Could not detect THP size, falling back to %" PRIx64
+ " MiB.", thp_size / MiB);
+ }
+
+ g_free(content);
+ return thp_size;
+}
+
+static uint64_t virtio_mem_default_block_size(RAMBlock *rb)
+{
+ const uint64_t page_size = qemu_ram_pagesize(rb);
+
+ /* We can have hugetlbfs with a page size smaller than the THP size. */
+ if (page_size == qemu_real_host_page_size) {
+ return MAX(page_size, virtio_mem_thp_size());
+ }
+ return MAX(page_size, VIRTIO_MEM_MIN_BLOCK_SIZE);
+}
+
/*
* Size the usable region bigger than the requested size if possible. Esp.
* Linux guests will only add (aligned) memory blocks in case they fully
@@ -227,6 +300,9 @@ static void virtio_mem_resize_usable_region(VirtIOMEM *vmem,
uint64_t newsize = MIN(memory_region_size(&vmem->memdev->mr),
requested_size + VIRTIO_MEM_USABLE_EXTENT);
+ /* The usable region size always has to be multiples of the block size. */
+ newsize = QEMU_ALIGN_UP(newsize, vmem->block_size);
+
if (!requested_size) {
newsize = 0;
}
@@ -440,15 +516,33 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp)
rb = vmem->memdev->mr.ram_block;
page_size = qemu_ram_pagesize(rb);
+ /*
+ * If the block size wasn't configured by the user, use a sane default. This
+ * allows using hugetlbfs backends of any page size without manual
+ * intervention.
+ */
+ if (!vmem->block_size) {
+ vmem->block_size = virtio_mem_default_block_size(rb);
+ }
+
if (vmem->block_size < page_size) {
error_setg(errp, "'%s' property has to be at least the page size (0x%"
PRIx64 ")", VIRTIO_MEM_BLOCK_SIZE_PROP, page_size);
return;
+ } else if (vmem->block_size < virtio_mem_default_block_size(rb)) {
+ warn_report("'%s' property is smaller than the default block size (%"
+ PRIx64 " MiB)", VIRTIO_MEM_BLOCK_SIZE_PROP,
+ virtio_mem_default_block_size(rb) / MiB);
} else if (!QEMU_IS_ALIGNED(vmem->requested_size, vmem->block_size)) {
error_setg(errp, "'%s' property has to be multiples of '%s' (0x%" PRIx64
")", VIRTIO_MEM_REQUESTED_SIZE_PROP,
VIRTIO_MEM_BLOCK_SIZE_PROP, vmem->block_size);
return;
+ } else if (!QEMU_IS_ALIGNED(vmem->addr, vmem->block_size)) {
+ error_setg(errp, "'%s' property has to be multiples of '%s' (0x%" PRIx64
+ ")", VIRTIO_MEM_ADDR_PROP, VIRTIO_MEM_BLOCK_SIZE_PROP,
+ vmem->block_size);
+ return;
} else if (!QEMU_IS_ALIGNED(memory_region_size(&vmem->memdev->mr),
vmem->block_size)) {
error_setg(errp, "'%s' property memdev size has to be multiples of"
@@ -734,6 +828,18 @@ static void virtio_mem_get_block_size(Object *obj, Visitor *v, const char *name,
const VirtIOMEM *vmem = VIRTIO_MEM(obj);
uint64_t value = vmem->block_size;
+ /*
+ * If not configured by the user (and we're not realized yet), use the
+ * default block size we would use with the current memory backend.
+ */
+ if (!value) {
+ if (vmem->memdev && memory_region_is_ram(&vmem->memdev->mr)) {
+ value = virtio_mem_default_block_size(vmem->memdev->mr.ram_block);
+ } else {
+ value = virtio_mem_thp_size();
+ }
+ }
+
visit_type_size(v, name, &value, errp);
}
@@ -813,7 +919,6 @@ static void virtio_mem_instance_init(Object *obj)
{
VirtIOMEM *vmem = VIRTIO_MEM(obj);
- vmem->block_size = VIRTIO_MEM_MIN_BLOCK_SIZE;
notifier_list_init(&vmem->size_change_notifiers);
vmem->precopy_notifier.notify = virtio_mem_precopy_notify;