Add a new member "guest_memfd" to memory backends. When it's set
to true, it enables RAM_GUEST_MEMFD in ram_flags, thus private kvm
guest_memfd will be allocated during RAMBlock allocation.
Memory backend's @guest_memfd is wired with @require_guest_memfd
field of MachineState. It avoid looking up the machine in phymem.c.
MachineState::require_guest_memfd is supposed to be set by any VMs
that requires KVM guest memfd as private memory, e.g., TDX VM.
Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
---
Changes in v4:
- rename "require_guest_memfd" to "guest_memfd" in struct
HostMemoryBackend; (David Hildenbrand)
---
backends/hostmem-file.c | 1 +
backends/hostmem-memfd.c | 1 +
backends/hostmem-ram.c | 1 +
backends/hostmem.c | 1 +
hw/core/machine.c | 5 +++++
include/hw/boards.h | 2 ++
include/sysemu/hostmem.h | 1 +
7 files changed, 12 insertions(+)
diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c
index ac3e433cbddb..3c69db794607 100644
--- a/backends/hostmem-file.c
+++ b/backends/hostmem-file.c
@@ -85,6 +85,7 @@ file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
ram_flags |= fb->readonly ? RAM_READONLY_FD : 0;
ram_flags |= fb->rom == ON_OFF_AUTO_ON ? RAM_READONLY : 0;
ram_flags |= backend->reserve ? 0 : RAM_NORESERVE;
+ ram_flags |= backend->guest_memfd ? RAM_GUEST_MEMFD : 0;
ram_flags |= fb->is_pmem ? RAM_PMEM : 0;
ram_flags |= RAM_NAMED_FILE;
return memory_region_init_ram_from_file(&backend->mr, OBJECT(backend), name,
diff --git a/backends/hostmem-memfd.c b/backends/hostmem-memfd.c
index 3923ea9364d5..745ead0034dc 100644
--- a/backends/hostmem-memfd.c
+++ b/backends/hostmem-memfd.c
@@ -55,6 +55,7 @@ memfd_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
name = host_memory_backend_get_name(backend);
ram_flags = backend->share ? RAM_SHARED : 0;
ram_flags |= backend->reserve ? 0 : RAM_NORESERVE;
+ ram_flags |= backend->guest_memfd ? RAM_GUEST_MEMFD : 0;
return memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), name,
backend->size, ram_flags, fd, 0, errp);
}
diff --git a/backends/hostmem-ram.c b/backends/hostmem-ram.c
index d121249f0f45..f7d81af783a5 100644
--- a/backends/hostmem-ram.c
+++ b/backends/hostmem-ram.c
@@ -30,6 +30,7 @@ ram_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
name = host_memory_backend_get_name(backend);
ram_flags = backend->share ? RAM_SHARED : 0;
ram_flags |= backend->reserve ? 0 : RAM_NORESERVE;
+ ram_flags |= backend->guest_memfd ? RAM_GUEST_MEMFD : 0;
return memory_region_init_ram_flags_nomigrate(&backend->mr, OBJECT(backend),
name, backend->size,
ram_flags, errp);
diff --git a/backends/hostmem.c b/backends/hostmem.c
index 81a72ce40b78..eb9682b4a856 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -277,6 +277,7 @@ static void host_memory_backend_init(Object *obj)
/* TODO: convert access to globals to compat properties */
backend->merge = machine_mem_merge(machine);
backend->dump = machine_dump_guest_core(machine);
+ backend->guest_memfd = machine_require_guest_memfd(machine);
backend->reserve = true;
backend->prealloc_threads = machine->smp.cpus;
}
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 9ac5d5389a6c..651a3d463a06 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -1192,6 +1192,11 @@ bool machine_mem_merge(MachineState *machine)
return machine->mem_merge;
}
+bool machine_require_guest_memfd(MachineState *machine)
+{
+ return machine->require_guest_memfd;
+}
+
static char *cpu_slot_to_string(const CPUArchId *cpu)
{
GString *s = g_string_new(NULL);
diff --git a/include/hw/boards.h b/include/hw/boards.h
index bcfde8a84d10..2e6156ae96b8 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -36,6 +36,7 @@ bool machine_usb(MachineState *machine);
int machine_phandle_start(MachineState *machine);
bool machine_dump_guest_core(MachineState *machine);
bool machine_mem_merge(MachineState *machine);
+bool machine_require_guest_memfd(MachineState *machine);
HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine);
void machine_set_cpu_numa_node(MachineState *machine,
const CpuInstanceProperties *props,
@@ -370,6 +371,7 @@ struct MachineState {
char *dt_compatible;
bool dump_guest_core;
bool mem_merge;
+ bool require_guest_memfd;
bool usb;
bool usb_disabled;
char *firmware;
diff --git a/include/sysemu/hostmem.h b/include/sysemu/hostmem.h
index 0e411aaa29e1..04b884bf42a6 100644
--- a/include/sysemu/hostmem.h
+++ b/include/sysemu/hostmem.h
@@ -74,6 +74,7 @@ struct HostMemoryBackend {
uint64_t size;
bool merge, dump, use_canonical_path;
bool prealloc, is_mapped, share, reserve;
+ bool guest_memfd;
uint32_t prealloc_threads;
ThreadContext *prealloc_context;
DECLARE_BITMAP(host_nodes, MAX_NODES + 1);
--
2.34.1
