* structure we are referencing to use. */
VMS_VSTRUCT = 0x8000,
+ /*
+ * This is a sub-flag for VMS_ARRAY_OF_POINTER. When this flag is set,
+ * VMS_ARRAY_OF_POINTER must also be set. When set, it means array
+ * elements can contain either valid or NULL pointers, vmstate core
+ * will be responsible for synchronizing the pointer status, providing
+ * proper memory allocations on the pointer when it is populated on the
+ * source QEMU. It also means the user of the field must make sure all
+ * the elements in the array are NULL pointers before loading. This
+ * should also work with VMS_ALLOC when the array itself also needs to
+ * be allocated.
+ */
+ VMS_ARRAY_OF_POINTER_AUTO_ALLOC = 0x10000,
+
/* Marker for end of list */
- VMS_END = 0x10000
+ VMS_END = 0x20000,
};
typedef enum {
.offset = vmstate_offset_array(_s, _f, _type*, _n), \
}
+/*
+ * For migrating a dynamically allocated uint{8,32}-indexed array of
+ * pointers to structures (with NULL entries and with auto memory
+ * allocation).
+ *
+ * _type: type of structure pointed to
+ * _vmsd: VMSD for structure _type (when VMS_STRUCT is set)
+ * _info: VMStateInfo for _type (when VMS_STRUCT is not set)
+ * start: size of (_type) pointed to (for auto memory allocation)
+ */
+#define VMSTATE_VARRAY_OF_POINTER_TO_STRUCT_UINT8_ALLOC(\
+ _field, _state, _field_num, _version, _vmsd, _type) { \
+ .name = (stringify(_field)), \
+ .version_id = (_version), \
+ .num_offset = vmstate_offset_value(_state, _field_num, uint8_t), \
+ .vmsd = &(_vmsd), \
+ .size = sizeof(_type), \
+ .flags = VMS_POINTER | VMS_VARRAY_UINT8 | \
+ VMS_ARRAY_OF_POINTER | VMS_STRUCT | \
+ VMS_ARRAY_OF_POINTER_AUTO_ALLOC, \
+ .offset = vmstate_offset_pointer(_state, _field, _type *), \
+}
+
+#define VMSTATE_VARRAY_OF_POINTER_TO_STRUCT_UINT32_ALLOC(\
+ _field, _state, _field_num, _version, _vmsd, _type) { \
+ .name = (stringify(_field)), \
+ .version_id = (_version), \
+ .num_offset = vmstate_offset_value(_state, _field_num, uint32_t), \
+ .vmsd = &(_vmsd), \
+ .size = sizeof(_type), \
+ .flags = VMS_POINTER | VMS_VARRAY_UINT32 | \
+ VMS_ARRAY_OF_POINTER | VMS_STRUCT | \
+ VMS_ARRAY_OF_POINTER_AUTO_ALLOC, \
+ .offset = vmstate_offset_pointer(_state, _field, _type *), \
+}
+
#define VMSTATE_VARRAY_OF_POINTER_UINT32(_field, _state, _field_num, _version, _info, _type) { \
.name = (stringify(_field)), \
.version_id = (_version), \
if (field) {
while (field->name) {
if (field->flags & VMS_ARRAY_OF_POINTER) {
- assert(field->size == 0);
+ if (field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC) {
+ /*
+ * Size must be provided because dest QEMU needs that
+ * info to know what to allocate
+ */
+ assert(field->size || field->size_offset);
+ } else {
+ /*
+ * Otherwise size info isn't useful (because it's
+ * always the size of host pointer), detect accidental
+ * setup of sizes in this case.
+ */
+ assert(field->size == 0 && field->size_offset == 0);
+ }
+ /*
+ * VMS_ARRAY_OF_POINTER must be used only together with one
+ * of VMS_(V)ARRAY* flags.
+ */
+ assert(field->flags & (VMS_ARRAY | VMS_VARRAY_INT32 |
+ VMS_VARRAY_UINT16 | VMS_VARRAY_UINT8 |
+ VMS_VARRAY_UINT32));
}
+
+ if (field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC) {
+ assert(field->flags & VMS_ARRAY_OF_POINTER);
+ }
+
if (field->flags & (VMS_STRUCT | VMS_VSTRUCT)) {
/* Recurse to sub structures */
vmstate_check(field->vmsd);
return true;
}
+ if (byte == VMS_MARKER_PTR_VALID) {
+ /* We need to load the field right after the marker */
+ *load_field = true;
+ return true;
+ }
+
error_setg(errp, "Unexpected ptr marker: %d", byte);
return false;
}
return true;
}
+/*
+ * Try to prepare loading the next element, the object pointer to be put
+ * into @next_elem. When @next_elem is NULL, it means we should skip
+ * loading this element.
+ *
+ * Returns false for errors, in which case *errp will be set, migration
+ * must be aborted.
+ */
+static bool vmstate_load_next(QEMUFile *f, const VMStateField *field,
+ void *first_elem, void **next_elem,
+ int size, int i, Error **errp)
+{
+ bool auto_alloc = field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC;
+ void *ptr = first_elem + size * i, **pptr;
+ bool load_field;
+
+ if (!(field->flags & VMS_ARRAY_OF_POINTER)) {
+ /* Simplest case, no pointer involved */
+ *next_elem = ptr;
+ return true;
+ }
+
+ /*
+ * We're loading an array of pointers, switch to use pptr to make it
+ * easier to read later
+ */
+ pptr = (void **)ptr;
+
+ /*
+ * If auto_alloc is on, making sure the user provided an array of NULL
+ * pointers to start with
+ */
+ assert(!auto_alloc || *pptr == NULL);
+
+ /*
+ * When pointer is null, we must expect a ptr marker first. Use cases:
+ *
+ * (1) _AUTO_ALLOC implies a ptr marker will always exist, or,
+ *
+ * (2) the element on destination is NULL, which expects the src to send a
+ * NULL-only marker.
+ *
+ * Here, checking against a NULL pointer will work for both.
+ */
+ if (!*pptr) {
+ if (!vmstate_ptr_marker_load(f, &load_field, errp)) {
+ trace_vmstate_load_field_error(field->name, -EINVAL);
+ return false;
+ }
+
+ /*
+ * If loading is needed, do pre-allocation first (otherwise keeping
+ * *pptr==NULL to imply a skip below)
+ */
+ if (load_field) {
+ /* Only applies when auto_alloc=on on the field */
+ assert(auto_alloc);
+ /*
+ * NOTE: do not use vmstate_size() here, because we need the
+ * object size, not entry size of the array.
+ */
+ *pptr = g_malloc0(field->size);
+ }
+ }
+
+ /* Move the cursor to the next element for loading */
+ *next_elem = *pptr;
+ return true;
+}
+
bool vmstate_load_vmsd(QEMUFile *f, const VMStateDescription *vmsd,
void *opaque, int version_id, Error **errp)
{
}
for (i = 0; i < n_elems; i++) {
- /* If we will process the load of field? */
- bool load_field = true;
- bool ok = true;
- void *curr_elem = first_elem + size * i;
+ void *curr_elem;
+ bool ok;
- if (field->flags & VMS_ARRAY_OF_POINTER) {
- curr_elem = *(void **)curr_elem;
- if (!curr_elem) {
- /* Read the marker instead of VMSD itself */
- if (!vmstate_ptr_marker_load(f, &load_field, errp)) {
- trace_vmstate_load_field_error(field->name,
- -EINVAL);
- return false;
- }
- }
+ ok = vmstate_load_next(f, field, first_elem, &curr_elem,
+ size, i, errp);
+ if (!ok) {
+ return false;
}
- if (load_field) {
- ok = vmstate_load_field(f, curr_elem, size, field, errp);
+ if (!curr_elem) {
+ /* Implies a skip */
+ continue;
}
+ ok = vmstate_load_field(f, curr_elem, size, field, errp);
+
if (ok) {
int ret = qemu_file_get_error(f);
if (ret < 0) {
return false;
}
+ if (field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC) {
+ /*
+ * This may involve two VMSD fields to be saved, one for the
+ * marker to show if the pointer is NULL, followed by the real
+ * vmstate object. To make it simple at least for now, skip
+ * compression for this one.
+ */
+ return false;
+ }
+
if (field->flags & VMS_STRUCT) {
const VMStateField *sfield = field->vmsd->fields;
while (sfield->name) {
int size = vmstate_size(opaque, field);
JSONWriter *vmdesc_loop = vmdesc;
bool is_prev_null = false;
+ /*
+ * When this is enabled, it means we will always push a ptr
+ * marker first for each element saying if it's populated.
+ */
+ bool use_dynamic_array =
+ field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC;
trace_vmstate_save_state_loop(vmsd->name, field->name, n_elems);
if (field->flags & VMS_POINTER) {
}
is_null = !curr_elem && size;
- use_marker_field = is_null;
+ use_marker_field = use_dynamic_array || is_null;
if (use_marker_field) {
- /*
- * If null pointer found (which should only happen in
- * an array of pointers), use null placeholder and do
- * not follow.
- */
inner_field = vmsd_create_ptr_marker_field(field);
} else {
inner_field = field;
goto out;
}
+ /*
+ * If we're using dynamic array and the element is
+ * populated, save the real object right after the marker.
+ */
+ if (use_dynamic_array && curr_elem) {
+ /*
+ * NOTE: do not use vmstate_size() here because we want
+ * to save the real VMSD object now.
+ */
+ ok = vmstate_save_field_with_vmdesc(f, curr_elem,
+ field->size, vmsd,
+ field, vmdesc_loop,
+ i, max_elems, errp);
+
+ if (!ok) {
+ goto out;
+ }
+ }
+
/* Compressed arrays only care about the first element */
if (vmdesc_loop && max_elems > 1) {
vmdesc_loop = NULL;
projects / thirdparty / qemu.git / commitdiff
