diff options
Diffstat (limited to 'migration/vmstate.c')
| -rw-r--r-- | migration/vmstate.c | 186 |
1 files changed, 180 insertions, 6 deletions
diff --git a/migration/vmstate.c b/migration/vmstate.c index dae5dd63af..e5388f0596 100644 --- a/migration/vmstate.c +++ b/migration/vmstate.c @@ -5,9 +5,10 @@ #include "qemu/bitops.h" #include "qemu/error-report.h" #include "trace.h" +#include "qjson.h" static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd, - void *opaque); + void *opaque, QJSON *vmdesc); static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd, void *opaque); @@ -146,32 +147,181 @@ int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd, return ret; } +static int vmfield_name_num(VMStateField *start, VMStateField *search) +{ + VMStateField *field; + int found = 0; + + for (field = start; field->name; field++) { + if (!strcmp(field->name, search->name)) { + if (field == search) { + return found; + } + found++; + } + } + + return -1; +} + +static bool vmfield_name_is_unique(VMStateField *start, VMStateField *search) +{ + VMStateField *field; + int found = 0; + + for (field = start; field->name; field++) { + if (!strcmp(field->name, search->name)) { + found++; + /* name found more than once, so it's not unique */ + if (found > 1) { + return false; + } + } + } + + return true; +} + +static const char *vmfield_get_type_name(VMStateField *field) +{ + const char *type = "unknown"; + + if (field->flags & VMS_STRUCT) { + type = "struct"; + } else if (field->info->name) { + type = field->info->name; + } + + return type; +} + +static bool vmsd_can_compress(VMStateField *field) +{ + if (field->field_exists) { + /* Dynamically existing fields mess up compression */ + return false; + } + + if (field->flags & VMS_STRUCT) { + VMStateField *sfield = field->vmsd->fields; + while (sfield->name) { + if (!vmsd_can_compress(sfield)) { + /* Child elements can't compress, so can't we */ + return false; + } + sfield++; + } + + if (field->vmsd->subsections) { + /* Subsections may come and go, better don't compress */ + return false; + } + } + + return true; +} + +static void vmsd_desc_field_start(const VMStateDescription *vmsd, QJSON *vmdesc, + VMStateField *field, int i, int max) +{ + char *name, *old_name; + bool is_array = max > 1; + bool can_compress = vmsd_can_compress(field); + + if (!vmdesc) { + return; + } + + name = g_strdup(field->name); + + /* Field name is not unique, need to make it unique */ + if (!vmfield_name_is_unique(vmsd->fields, field)) { + int num = vmfield_name_num(vmsd->fields, field); + old_name = name; + name = g_strdup_printf("%s[%d]", name, num); + g_free(old_name); + } + + json_start_object(vmdesc, NULL); + json_prop_str(vmdesc, "name", name); + if (is_array) { + if (can_compress) { + json_prop_int(vmdesc, "array_len", max); + } else { + json_prop_int(vmdesc, "index", i); + } + } + json_prop_str(vmdesc, "type", vmfield_get_type_name(field)); + + if (field->flags & VMS_STRUCT) { + json_start_object(vmdesc, "struct"); + } + + g_free(name); +} + +static void vmsd_desc_field_end(const VMStateDescription *vmsd, QJSON *vmdesc, + VMStateField *field, size_t size, int i) +{ + if (!vmdesc) { + return; + } + + if (field->flags & VMS_STRUCT) { + /* We printed a struct in between, close its child object */ + json_end_object(vmdesc); + } + + json_prop_int(vmdesc, "size", size); + json_end_object(vmdesc); +} + void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd, - void *opaque) + void *opaque, QJSON *vmdesc) { VMStateField *field = vmsd->fields; if (vmsd->pre_save) { vmsd->pre_save(opaque); } + + if (vmdesc) { + json_prop_str(vmdesc, "vmsd_name", vmsd->name); + json_prop_int(vmdesc, "version", vmsd->version_id); + json_start_array(vmdesc, "fields"); + } + while (field->name) { if (!field->field_exists || field->field_exists(opaque, vmsd->version_id)) { void *base_addr = vmstate_base_addr(opaque, field, false); int i, n_elems = vmstate_n_elems(opaque, field); int size = vmstate_size(opaque, field); + int64_t old_offset, written_bytes; + QJSON *vmdesc_loop = vmdesc; for (i = 0; i < n_elems; i++) { void *addr = base_addr + size * i; + vmsd_desc_field_start(vmsd, vmdesc_loop, field, i, n_elems); + old_offset = qemu_ftell_fast(f); + if (field->flags & VMS_ARRAY_OF_POINTER) { addr = *(void **)addr; } if (field->flags & VMS_STRUCT) { - vmstate_save_state(f, field->vmsd, addr); + vmstate_save_state(f, field->vmsd, addr, vmdesc_loop); } else { field->info->put(f, addr, size); } + + written_bytes = qemu_ftell_fast(f) - old_offset; + vmsd_desc_field_end(vmsd, vmdesc_loop, field, written_bytes, i); + + /* Compressed arrays only care about the first element */ + if (vmdesc_loop && vmsd_can_compress(field)) { + vmdesc_loop = NULL; + } } } else { if (field->flags & VMS_MUST_EXIST) { @@ -182,7 +332,12 @@ void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd, } field++; } - vmstate_subsection_save(f, vmsd, opaque); + + if (vmdesc) { + json_end_array(vmdesc); + } + + vmstate_subsection_save(f, vmsd, opaque, vmdesc); } static const VMStateDescription * @@ -248,24 +403,43 @@ static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd, } static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd, - void *opaque) + void *opaque, QJSON *vmdesc) { const VMStateSubsection *sub = vmsd->subsections; + bool subsection_found = false; while (sub && sub->needed) { if (sub->needed(opaque)) { const VMStateDescription *vmsd = sub->vmsd; uint8_t len; + if (vmdesc) { + /* Only create subsection array when we have any */ + if (!subsection_found) { + json_start_array(vmdesc, "subsections"); + subsection_found = true; + } + + json_start_object(vmdesc, NULL); + } + qemu_put_byte(f, QEMU_VM_SUBSECTION); len = strlen(vmsd->name); qemu_put_byte(f, len); qemu_put_buffer(f, (uint8_t *)vmsd->name, len); qemu_put_be32(f, vmsd->version_id); - vmstate_save_state(f, vmsd, opaque); + vmstate_save_state(f, vmsd, opaque, vmdesc); + + if (vmdesc) { + json_end_object(vmdesc); + } } sub++; } + + if (vmdesc && subsection_found) { + json_end_array(vmdesc); + } } /* bool */ |