dm vdo: save the formatted metadata to disk

Add vdo_save_super_block() and vdo_save_geometry_block() to perform
asynchronous writes of the super block and geometry block respectively.
Add vdo_clear_layout() to zero the UDS index's first block, the block
map partition, and the recovery journal partition.

These operations are driven by new phases in the pre-load state machine
(PRE_LOAD_PHASE_FORMAT_*), ensuring that disk writes happen during
pre-resume rather than during dmsetup create.

Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Reviewed-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
This commit is contained in:
Bruce Johnston 2026-03-24 14:06:52 -04:00 committed by Mikulas Patocka
parent defce4e039
commit fc1d438267
3 changed files with 147 additions and 20 deletions

View File

@ -61,6 +61,11 @@ enum admin_phases {
LOAD_PHASE_DRAIN_JOURNAL,
LOAD_PHASE_WAIT_FOR_READ_ONLY,
PRE_LOAD_PHASE_START,
PRE_LOAD_PHASE_FORMAT_START,
PRE_LOAD_PHASE_FORMAT_SUPER,
PRE_LOAD_PHASE_FORMAT_GEOMETRY,
PRE_LOAD_PHASE_FORMAT_END,
PRE_LOAD_PHASE_LOAD_SUPER,
PRE_LOAD_PHASE_LOAD_COMPONENTS,
PRE_LOAD_PHASE_END,
PREPARE_GROW_PHYSICAL_PHASE_START,
@ -110,6 +115,11 @@ static const char * const ADMIN_PHASE_NAMES[] = {
"LOAD_PHASE_DRAIN_JOURNAL",
"LOAD_PHASE_WAIT_FOR_READ_ONLY",
"PRE_LOAD_PHASE_START",
"PRE_LOAD_PHASE_FORMAT_START",
"PRE_LOAD_PHASE_FORMAT_SUPER",
"PRE_LOAD_PHASE_FORMAT_GEOMETRY",
"PRE_LOAD_PHASE_FORMAT_END",
"PRE_LOAD_PHASE_LOAD_SUPER",
"PRE_LOAD_PHASE_LOAD_COMPONENTS",
"PRE_LOAD_PHASE_END",
"PREPARE_GROW_PHYSICAL_PHASE_START",
@ -1487,7 +1497,33 @@ static void pre_load_callback(struct vdo_completion *completion)
vdo_continue_completion(completion, result);
return;
}
if (vdo->needs_formatting)
vdo->admin.phase = PRE_LOAD_PHASE_FORMAT_START;
else
vdo->admin.phase = PRE_LOAD_PHASE_LOAD_SUPER;
vdo_continue_completion(completion, VDO_SUCCESS);
return;
case PRE_LOAD_PHASE_FORMAT_START:
vdo_continue_completion(completion, vdo_clear_layout(vdo));
return;
case PRE_LOAD_PHASE_FORMAT_SUPER:
vdo_save_super_block(vdo, completion);
return;
case PRE_LOAD_PHASE_FORMAT_GEOMETRY:
vdo_save_geometry_block(vdo, completion);
return;
case PRE_LOAD_PHASE_FORMAT_END:
/* cleanup layout before load adds to it */
vdo_uninitialize_layout(&vdo->states.layout);
vdo_continue_completion(completion, VDO_SUCCESS);
return;
case PRE_LOAD_PHASE_LOAD_SUPER:
vdo_load_super_block(vdo, completion);
return;

View File

@ -491,6 +491,8 @@ static int __must_check vdo_format(struct vdo *vdo, char **error_ptr)
return result;
}
vdo->needs_formatting = true;
return VDO_SUCCESS;
}
@ -951,24 +953,101 @@ static void record_vdo(struct vdo *vdo)
vdo->states.layout = vdo->layout;
}
static int __must_check clear_partition(struct vdo *vdo, enum partition_id id)
{
struct partition *partition;
int result;
result = vdo_get_partition(&vdo->states.layout, id, &partition);
if (result != VDO_SUCCESS)
return result;
return blkdev_issue_zeroout(vdo_get_backing_device(vdo),
partition->offset * VDO_SECTORS_PER_BLOCK,
partition->count * VDO_SECTORS_PER_BLOCK,
GFP_NOWAIT, 0);
}
int vdo_clear_layout(struct vdo *vdo)
{
int result;
/* Zero out the uds index's first block. */
result = blkdev_issue_zeroout(vdo_get_backing_device(vdo),
VDO_SECTORS_PER_BLOCK,
VDO_SECTORS_PER_BLOCK,
GFP_NOWAIT, 0);
if (result != VDO_SUCCESS)
return result;
result = clear_partition(vdo, VDO_BLOCK_MAP_PARTITION);
if (result != VDO_SUCCESS)
return result;
return clear_partition(vdo, VDO_RECOVERY_JOURNAL_PARTITION);
}
/**
* continue_super_block_parent() - Continue the parent of a super block save operation.
* @completion: The super block vio.
* continue_parent() - Continue the parent of a save operation.
* @completion: The completion to continue.
*
* This callback is registered in vdo_save_components().
*/
static void continue_super_block_parent(struct vdo_completion *completion)
static void continue_parent(struct vdo_completion *completion)
{
vdo_continue_completion(vdo_forget(completion->parent), completion->result);
}
static void handle_write_endio(struct bio *bio)
{
struct vio *vio = bio->bi_private;
struct vdo_completion *parent = vio->completion.parent;
continue_vio_after_io(vio, continue_parent,
parent->callback_thread_id);
}
/**
* handle_save_error() - Log a super block save error.
* handle_geometry_block_save_error() - Log a geometry block save error.
* @completion: The super block vio.
*
* This error handler is registered in vdo_save_geometry_block().
*/
static void handle_geometry_block_save_error(struct vdo_completion *completion)
{
struct vdo_geometry_block *geometry_block =
container_of(as_vio(completion), struct vdo_geometry_block, vio);
vio_record_metadata_io_error(&geometry_block->vio);
vdo_log_error_strerror(completion->result, "geometry block save failed");
completion->callback(completion);
}
/**
* vdo_save_geometry_block() - Encode the vdo and save the geometry block asynchronously.
* @vdo: The vdo whose state is being saved.
* @parent: The completion to notify when the save is complete.
*/
void vdo_save_geometry_block(struct vdo *vdo, struct vdo_completion *parent)
{
struct vdo_geometry_block *geometry_block = &vdo->geometry_block;
vdo_encode_volume_geometry(geometry_block->buffer, &vdo->geometry,
VDO_DEFAULT_GEOMETRY_BLOCK_VERSION);
geometry_block->vio.completion.parent = parent;
geometry_block->vio.completion.callback_thread_id = parent->callback_thread_id;
vdo_submit_metadata_vio(&geometry_block->vio,
VDO_GEOMETRY_BLOCK_LOCATION,
handle_write_endio, handle_geometry_block_save_error,
REQ_OP_WRITE | REQ_PREFLUSH | REQ_FUA);
}
/**
* handle_super_block_save_error() - Log a super block save error.
* @completion: The super block vio.
*
* This error handler is registered in vdo_save_components().
*/
static void handle_save_error(struct vdo_completion *completion)
static void handle_super_block_save_error(struct vdo_completion *completion)
{
struct vdo_super_block *super_block =
container_of(as_vio(completion), struct vdo_super_block, vio);
@ -987,17 +1066,27 @@ static void handle_save_error(struct vdo_completion *completion)
completion->callback(completion);
}
static void super_block_write_endio(struct bio *bio)
/**
* vdo_save_super_block() - Save the component states to the super block asynchronously.
* @vdo: The vdo whose state is being saved.
* @parent: The completion to notify when the save is complete.
*/
void vdo_save_super_block(struct vdo *vdo, struct vdo_completion *parent)
{
struct vio *vio = bio->bi_private;
struct vdo_completion *parent = vio->completion.parent;
struct vdo_super_block *super_block = &vdo->super_block;
continue_vio_after_io(vio, continue_super_block_parent,
parent->callback_thread_id);
vdo_encode_super_block(super_block->buffer, &vdo->states);
super_block->vio.completion.parent = parent;
super_block->vio.completion.callback_thread_id = parent->callback_thread_id;
vdo_submit_metadata_vio(&super_block->vio,
vdo_get_data_region_start(vdo->geometry),
handle_write_endio, handle_super_block_save_error,
REQ_OP_WRITE | REQ_PREFLUSH | REQ_FUA);
}
/**
* vdo_save_components() - Encode the vdo and save the super block asynchronously.
* vdo_save_components() - Copy the current state of the VDO to the states struct and save
* it to the super block asynchronously.
* @vdo: The vdo whose state is being saved.
* @parent: The completion to notify when the save is complete.
*/
@ -1016,14 +1105,7 @@ void vdo_save_components(struct vdo *vdo, struct vdo_completion *parent)
}
record_vdo(vdo);
vdo_encode_super_block(super_block->buffer, &vdo->states);
super_block->vio.completion.parent = parent;
super_block->vio.completion.callback_thread_id = parent->callback_thread_id;
vdo_submit_metadata_vio(&super_block->vio,
vdo_get_data_region_start(vdo->geometry),
super_block_write_endio, handle_save_error,
REQ_OP_WRITE | REQ_PREFLUSH | REQ_FUA);
vdo_save_super_block(vdo, parent);
}
/**

View File

@ -246,6 +246,7 @@ struct vdo {
const struct admin_state_code *suspend_type;
bool allocations_allowed;
bool dump_on_shutdown;
bool needs_formatting;
atomic_t processing_message;
/*
@ -314,6 +315,10 @@ int __must_check vdo_make(unsigned int instance, struct device_config *config,
void vdo_destroy(struct vdo *vdo);
int __must_check vdo_format_components(struct vdo *vdo);
void vdo_format_super_block(struct vdo *vdo, struct vdo_completion *parent);
void vdo_load_super_block(struct vdo *vdo, struct vdo_completion *parent);
struct block_device * __must_check vdo_get_backing_device(const struct vdo *vdo);
@ -336,6 +341,10 @@ enum vdo_state __must_check vdo_get_state(const struct vdo *vdo);
void vdo_set_state(struct vdo *vdo, enum vdo_state state);
int vdo_clear_layout(struct vdo *vdo);
void vdo_save_geometry_block(struct vdo *vdo, struct vdo_completion *parent);
void vdo_save_super_block(struct vdo *vdo, struct vdo_completion *parent);
void vdo_save_components(struct vdo *vdo, struct vdo_completion *parent);
int vdo_register_read_only_listener(struct vdo *vdo, void *listener,