diff options
| -rw-r--r-- | migration/savevm.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/migration/savevm.c b/migration/savevm.c index a831ec2d67..cfcbbd00d3 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -265,6 +265,7 @@ typedef struct SaveState { bool skip_configuration; uint32_t len; const char *name; + uint32_t target_page_bits; } SaveState; static SaveState savevm_state = { @@ -286,6 +287,19 @@ static void configuration_pre_save(void *opaque) state->len = strlen(current_name); state->name = current_name; + state->target_page_bits = TARGET_PAGE_BITS; +} + +static int configuration_pre_load(void *opaque) +{ + SaveState *state = opaque; + + /* If there is no target-page-bits subsection it means the source + * predates the variable-target-page-bits support and is using the + * minimum possible value for this CPU. + */ + state->target_page_bits = TARGET_PAGE_BITS_MIN; + return 0; } static int configuration_post_load(void *opaque, int version_id) @@ -298,12 +312,43 @@ static int configuration_post_load(void *opaque, int version_id) (int) state->len, state->name, current_name); return -EINVAL; } + + if (state->target_page_bits != TARGET_PAGE_BITS) { + error_report("Received TARGET_PAGE_BITS is %d but local is %d", + state->target_page_bits, TARGET_PAGE_BITS); + return -EINVAL; + } + return 0; } +/* The target-page-bits subsection is present only if the + * target page size is not the same as the default (ie the + * minimum page size for a variable-page-size guest CPU). + * If it is present then it contains the actual target page + * bits for the machine, and migration will fail if the + * two ends don't agree about it. + */ +static bool vmstate_target_page_bits_needed(void *opaque) +{ + return TARGET_PAGE_BITS > TARGET_PAGE_BITS_MIN; +} + +static const VMStateDescription vmstate_target_page_bits = { + .name = "configuration/target-page-bits", + .version_id = 1, + .minimum_version_id = 1, + .needed = vmstate_target_page_bits_needed, + .fields = (VMStateField[]) { + VMSTATE_UINT32(target_page_bits, SaveState), + VMSTATE_END_OF_LIST() + } +}; + static const VMStateDescription vmstate_configuration = { .name = "configuration", .version_id = 1, + .pre_load = configuration_pre_load, .post_load = configuration_post_load, .pre_save = configuration_pre_save, .fields = (VMStateField[]) { @@ -311,6 +356,10 @@ static const VMStateDescription vmstate_configuration = { VMSTATE_VBUFFER_ALLOC_UINT32(name, SaveState, 0, NULL, 0, len), VMSTATE_END_OF_LIST() }, + .subsections = (const VMStateDescription*[]) { + &vmstate_target_page_bits, + NULL + } }; static void dump_vmstate_vmsd(FILE *out_file, |