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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright 2023 Red Hat4 */5 6#include "packer.h"7 8#include <linux/atomic.h>9#include <linux/blkdev.h>10 11#include "logger.h"12#include "memory-alloc.h"13#include "permassert.h"14#include "string-utils.h"15 16#include "admin-state.h"17#include "completion.h"18#include "constants.h"19#include "data-vio.h"20#include "dedupe.h"21#include "encodings.h"22#include "io-submitter.h"23#include "physical-zone.h"24#include "status-codes.h"25#include "vdo.h"26#include "vio.h"27 28static const struct version_number COMPRESSED_BLOCK_1_0 = {29	.major_version = 1,30	.minor_version = 0,31};32 33#define COMPRESSED_BLOCK_1_0_SIZE (4 + 4 + (2 * VDO_MAX_COMPRESSION_SLOTS))34 35/**36 * vdo_get_compressed_block_fragment() - Get a reference to a compressed fragment from a compressed37 *                                       block.38 * @mapping_state [in] The mapping state for the look up.39 * @compressed_block [in] The compressed block that was read from disk.40 * @fragment_offset [out] The offset of the fragment within a compressed block.41 * @fragment_size [out] The size of the fragment.42 *43 * Return: If a valid compressed fragment is found, VDO_SUCCESS; otherwise, VDO_INVALID_FRAGMENT if44 *         the fragment is invalid.45 */46int vdo_get_compressed_block_fragment(enum block_mapping_state mapping_state,47				      struct compressed_block *block,48				      u16 *fragment_offset, u16 *fragment_size)49{50	u16 compressed_size;51	u16 offset = 0;52	unsigned int i;53	u8 slot;54	struct version_number version;55 56	if (!vdo_is_state_compressed(mapping_state))57		return VDO_INVALID_FRAGMENT;58 59	version = vdo_unpack_version_number(block->header.version);60	if (!vdo_are_same_version(version, COMPRESSED_BLOCK_1_0))61		return VDO_INVALID_FRAGMENT;62 63	slot = mapping_state - VDO_MAPPING_STATE_COMPRESSED_BASE;64	if (slot >= VDO_MAX_COMPRESSION_SLOTS)65		return VDO_INVALID_FRAGMENT;66 67	compressed_size = __le16_to_cpu(block->header.sizes[slot]);68	for (i = 0; i < slot; i++) {69		offset += __le16_to_cpu(block->header.sizes[i]);70		if (offset >= VDO_COMPRESSED_BLOCK_DATA_SIZE)71			return VDO_INVALID_FRAGMENT;72	}73 74	if ((offset + compressed_size) > VDO_COMPRESSED_BLOCK_DATA_SIZE)75		return VDO_INVALID_FRAGMENT;76 77	*fragment_offset = offset;78	*fragment_size = compressed_size;79	return VDO_SUCCESS;80}81 82/**83 * assert_on_packer_thread() - Check that we are on the packer thread.84 * @packer: The packer.85 * @caller: The function which is asserting.86 */87static inline void assert_on_packer_thread(struct packer *packer, const char *caller)88{89	VDO_ASSERT_LOG_ONLY((vdo_get_callback_thread_id() == packer->thread_id),90			    "%s() called from packer thread", caller);91}92 93/**94 * insert_in_sorted_list() - Insert a bin to the list.95 * @packer: The packer.96 * @bin: The bin to move to its sorted position.97 *98 * The list is in ascending order of free space. Since all bins are already in the list, this99 * actually moves the bin to the correct position in the list.100 */101static void insert_in_sorted_list(struct packer *packer, struct packer_bin *bin)102{103	struct packer_bin *active_bin;104 105	list_for_each_entry(active_bin, &packer->bins, list)106		if (active_bin->free_space > bin->free_space) {107			list_move_tail(&bin->list, &active_bin->list);108			return;109		}110 111	list_move_tail(&bin->list, &packer->bins);112}113 114/**115 * make_bin() - Allocate a bin and put it into the packer's list.116 * @packer: The packer.117 */118static int __must_check make_bin(struct packer *packer)119{120	struct packer_bin *bin;121	int result;122 123	result = vdo_allocate_extended(struct packer_bin, VDO_MAX_COMPRESSION_SLOTS,124				       struct vio *, __func__, &bin);125	if (result != VDO_SUCCESS)126		return result;127 128	bin->free_space = VDO_COMPRESSED_BLOCK_DATA_SIZE;129	INIT_LIST_HEAD(&bin->list);130	list_add_tail(&bin->list, &packer->bins);131	return VDO_SUCCESS;132}133 134/**135 * vdo_make_packer() - Make a new block packer.136 *137 * @vdo: The vdo to which this packer belongs.138 * @bin_count: The number of partial bins to keep in memory.139 * @packer_ptr: A pointer to hold the new packer.140 *141 * Return: VDO_SUCCESS or an error142 */143int vdo_make_packer(struct vdo *vdo, block_count_t bin_count, struct packer **packer_ptr)144{145	struct packer *packer;146	block_count_t i;147	int result;148 149	result = vdo_allocate(1, struct packer, __func__, &packer);150	if (result != VDO_SUCCESS)151		return result;152 153	packer->thread_id = vdo->thread_config.packer_thread;154	packer->size = bin_count;155	INIT_LIST_HEAD(&packer->bins);156	vdo_set_admin_state_code(&packer->state, VDO_ADMIN_STATE_NORMAL_OPERATION);157 158	for (i = 0; i < bin_count; i++) {159		result = make_bin(packer);160		if (result != VDO_SUCCESS) {161			vdo_free_packer(packer);162			return result;163		}164	}165 166	/*167	 * The canceled bin can hold up to half the number of user vios. Every canceled vio in the168	 * bin must have a canceler for which it is waiting, and any canceler will only have169	 * canceled one lock holder at a time.170	 */171	result = vdo_allocate_extended(struct packer_bin, MAXIMUM_VDO_USER_VIOS / 2,172				       struct vio *, __func__, &packer->canceled_bin);173	if (result != VDO_SUCCESS) {174		vdo_free_packer(packer);175		return result;176	}177 178	result = vdo_make_default_thread(vdo, packer->thread_id);179	if (result != VDO_SUCCESS) {180		vdo_free_packer(packer);181		return result;182	}183 184	*packer_ptr = packer;185	return VDO_SUCCESS;186}187 188/**189 * vdo_free_packer() - Free a block packer.190 * @packer: The packer to free.191 */192void vdo_free_packer(struct packer *packer)193{194	struct packer_bin *bin, *tmp;195 196	if (packer == NULL)197		return;198 199	list_for_each_entry_safe(bin, tmp, &packer->bins, list) {200		list_del_init(&bin->list);201		vdo_free(bin);202	}203 204	vdo_free(vdo_forget(packer->canceled_bin));205	vdo_free(packer);206}207 208/**209 * get_packer_from_data_vio() - Get the packer from a data_vio.210 * @data_vio: The data_vio.211 *212 * Return: The packer from the VDO to which the data_vio belongs.213 */214static inline struct packer *get_packer_from_data_vio(struct data_vio *data_vio)215{216	return vdo_from_data_vio(data_vio)->packer;217}218 219/**220 * vdo_get_packer_statistics() - Get the current statistics from the packer.221 * @packer: The packer to query.222 *223 * Return: a copy of the current statistics for the packer.224 */225struct packer_statistics vdo_get_packer_statistics(const struct packer *packer)226{227	const struct packer_statistics *stats = &packer->statistics;228 229	return (struct packer_statistics) {230		.compressed_fragments_written = READ_ONCE(stats->compressed_fragments_written),231		.compressed_blocks_written = READ_ONCE(stats->compressed_blocks_written),232		.compressed_fragments_in_packer = READ_ONCE(stats->compressed_fragments_in_packer),233	};234}235 236/**237 * abort_packing() - Abort packing a data_vio.238 * @data_vio: The data_vio to abort.239 */240static void abort_packing(struct data_vio *data_vio)241{242	struct packer *packer = get_packer_from_data_vio(data_vio);243 244	WRITE_ONCE(packer->statistics.compressed_fragments_in_packer,245		   packer->statistics.compressed_fragments_in_packer - 1);246 247	write_data_vio(data_vio);248}249 250/**251 * release_compressed_write_waiter() - Update a data_vio for which a successful compressed write252 *                                     has completed and send it on its way.253 254 * @data_vio: The data_vio to release.255 * @allocation: The allocation to which the compressed block was written.256 */257static void release_compressed_write_waiter(struct data_vio *data_vio,258					    struct allocation *allocation)259{260	data_vio->new_mapped = (struct zoned_pbn) {261		.pbn = allocation->pbn,262		.zone = allocation->zone,263		.state = data_vio->compression.slot + VDO_MAPPING_STATE_COMPRESSED_BASE,264	};265 266	vdo_share_compressed_write_lock(data_vio, allocation->lock);267	update_metadata_for_data_vio_write(data_vio, allocation->lock);268}269 270/**271 * finish_compressed_write() - Finish a compressed block write.272 * @completion: The compressed write completion.273 *274 * This callback is registered in continue_after_allocation().275 */276static void finish_compressed_write(struct vdo_completion *completion)277{278	struct data_vio *agent = as_data_vio(completion);279	struct data_vio *client, *next;280 281	assert_data_vio_in_allocated_zone(agent);282 283	/*284	 * Process all the non-agent waiters first to ensure that the pbn lock can not be released285	 * until all of them have had a chance to journal their increfs.286	 */287	for (client = agent->compression.next_in_batch; client != NULL; client = next) {288		next = client->compression.next_in_batch;289		release_compressed_write_waiter(client, &agent->allocation);290	}291 292	completion->error_handler = handle_data_vio_error;293	release_compressed_write_waiter(agent, &agent->allocation);294}295 296static void handle_compressed_write_error(struct vdo_completion *completion)297{298	struct data_vio *agent = as_data_vio(completion);299	struct allocation *allocation = &agent->allocation;300	struct data_vio *client, *next;301 302	if (vdo_requeue_completion_if_needed(completion, allocation->zone->thread_id))303		return;304 305	update_vio_error_stats(as_vio(completion),306			       "Completing compressed write vio for physical block %llu with error",307			       (unsigned long long) allocation->pbn);308 309	for (client = agent->compression.next_in_batch; client != NULL; client = next) {310		next = client->compression.next_in_batch;311		write_data_vio(client);312	}313 314	/* Now that we've released the batch from the packer, forget the error and continue on. */315	vdo_reset_completion(completion);316	completion->error_handler = handle_data_vio_error;317	write_data_vio(agent);318}319 320/**321 * add_to_bin() - Put a data_vio in a specific packer_bin in which it will definitely fit.322 * @bin: The bin in which to put the data_vio.323 * @data_vio: The data_vio to add.324 */325static void add_to_bin(struct packer_bin *bin, struct data_vio *data_vio)326{327	data_vio->compression.bin = bin;328	data_vio->compression.slot = bin->slots_used;329	bin->incoming[bin->slots_used++] = data_vio;330}331 332/**333 * remove_from_bin() - Get the next data_vio whose compression has not been canceled from a bin.334 * @packer: The packer.335 * @bin: The bin from which to get a data_vio.336 *337 * Any canceled data_vios will be moved to the canceled bin.338 * Return: An uncanceled data_vio from the bin or NULL if there are none.339 */340static struct data_vio *remove_from_bin(struct packer *packer, struct packer_bin *bin)341{342	while (bin->slots_used > 0) {343		struct data_vio *data_vio = bin->incoming[--bin->slots_used];344 345		if (!advance_data_vio_compression_stage(data_vio).may_not_compress) {346			data_vio->compression.bin = NULL;347			return data_vio;348		}349 350		add_to_bin(packer->canceled_bin, data_vio);351	}352 353	/* The bin is now empty. */354	bin->free_space = VDO_COMPRESSED_BLOCK_DATA_SIZE;355	return NULL;356}357 358/**359 * initialize_compressed_block() - Initialize a compressed block.360 * @block: The compressed block to initialize.361 * @size: The size of the agent's fragment.362 *363 * This method initializes the compressed block in the compressed write agent. Because the364 * compressor already put the agent's compressed fragment at the start of the compressed block's365 * data field, it needn't be copied. So all we need do is initialize the header and set the size of366 * the agent's fragment.367 */368static void initialize_compressed_block(struct compressed_block *block, u16 size)369{370	/*371	 * Make sure the block layout isn't accidentally changed by changing the length of the372	 * block header.373	 */374	BUILD_BUG_ON(sizeof(struct compressed_block_header) != COMPRESSED_BLOCK_1_0_SIZE);375 376	block->header.version = vdo_pack_version_number(COMPRESSED_BLOCK_1_0);377	block->header.sizes[0] = __cpu_to_le16(size);378}379 380/**381 * pack_fragment() - Pack a data_vio's fragment into the compressed block in which it is already382 *                   known to fit.383 * @compression: The agent's compression_state to pack in to.384 * @data_vio: The data_vio to pack.385 * @offset: The offset into the compressed block at which to pack the fragment.386 * @compressed_block: The compressed block which will be written out when batch is fully packed.387 *388 * Return: The new amount of space used.389 */390static block_size_t __must_check pack_fragment(struct compression_state *compression,391					       struct data_vio *data_vio,392					       block_size_t offset, slot_number_t slot,393					       struct compressed_block *block)394{395	struct compression_state *to_pack = &data_vio->compression;396	char *fragment = to_pack->block->data;397 398	to_pack->next_in_batch = compression->next_in_batch;399	compression->next_in_batch = data_vio;400	to_pack->slot = slot;401	block->header.sizes[slot] = __cpu_to_le16(to_pack->size);402	memcpy(&block->data[offset], fragment, to_pack->size);403	return (offset + to_pack->size);404}405 406/**407 * compressed_write_end_io() - The bio_end_io for a compressed block write.408 * @bio: The bio for the compressed write.409 */410static void compressed_write_end_io(struct bio *bio)411{412	struct data_vio *data_vio = vio_as_data_vio(bio->bi_private);413 414	vdo_count_completed_bios(bio);415	set_data_vio_allocated_zone_callback(data_vio, finish_compressed_write);416	continue_data_vio_with_error(data_vio, blk_status_to_errno(bio->bi_status));417}418 419/**420 * write_bin() - Write out a bin.421 * @packer: The packer.422 * @bin: The bin to write.423 */424static void write_bin(struct packer *packer, struct packer_bin *bin)425{426	int result;427	block_size_t offset;428	slot_number_t slot = 1;429	struct compression_state *compression;430	struct compressed_block *block;431	struct data_vio *agent = remove_from_bin(packer, bin);432	struct data_vio *client;433	struct packer_statistics *stats;434 435	if (agent == NULL)436		return;437 438	compression = &agent->compression;439	compression->slot = 0;440	block = compression->block;441	initialize_compressed_block(block, compression->size);442	offset = compression->size;443 444	while ((client = remove_from_bin(packer, bin)) != NULL)445		offset = pack_fragment(compression, client, offset, slot++, block);446 447	/*448	 * If the batch contains only a single vio, then we save nothing by saving the compressed449	 * form. Continue processing the single vio in the batch.450	 */451	if (slot == 1) {452		abort_packing(agent);453		return;454	}455 456	if (slot < VDO_MAX_COMPRESSION_SLOTS) {457		/* Clear out the sizes of the unused slots */458		memset(&block->header.sizes[slot], 0,459		       (VDO_MAX_COMPRESSION_SLOTS - slot) * sizeof(__le16));460	}461 462	agent->vio.completion.error_handler = handle_compressed_write_error;463	if (vdo_is_read_only(vdo_from_data_vio(agent))) {464		continue_data_vio_with_error(agent, VDO_READ_ONLY);465		return;466	}467 468	result = vio_reset_bio(&agent->vio, (char *) block, compressed_write_end_io,469			       REQ_OP_WRITE, agent->allocation.pbn);470	if (result != VDO_SUCCESS) {471		continue_data_vio_with_error(agent, result);472		return;473	}474 475	/*476	 * Once the compressed write is submitted, the fragments are no longer in the packer, so477	 * update stats now.478	 */479	stats = &packer->statistics;480	WRITE_ONCE(stats->compressed_fragments_in_packer,481		   (stats->compressed_fragments_in_packer - slot));482	WRITE_ONCE(stats->compressed_fragments_written,483		   (stats->compressed_fragments_written + slot));484	WRITE_ONCE(stats->compressed_blocks_written,485		   stats->compressed_blocks_written + 1);486 487	vdo_submit_data_vio(agent);488}489 490/**491 * add_data_vio_to_packer_bin() - Add a data_vio to a bin's incoming queue492 * @packer: The packer.493 * @bin: The bin to which to add the data_vio.494 * @data_vio: The data_vio to add to the bin's queue.495 *496 * Adds a data_vio to a bin's incoming queue, handles logical space change, and calls physical497 * space processor.498 */499static void add_data_vio_to_packer_bin(struct packer *packer, struct packer_bin *bin,500				       struct data_vio *data_vio)501{502	/* If the selected bin doesn't have room, start a new batch to make room. */503	if (bin->free_space < data_vio->compression.size)504		write_bin(packer, bin);505 506	add_to_bin(bin, data_vio);507	bin->free_space -= data_vio->compression.size;508 509	/* If we happen to exactly fill the bin, start a new batch. */510	if ((bin->slots_used == VDO_MAX_COMPRESSION_SLOTS) ||511	    (bin->free_space == 0))512		write_bin(packer, bin);513 514	/* Now that we've finished changing the free space, restore the sort order. */515	insert_in_sorted_list(packer, bin);516}517 518/**519 * select_bin() - Select the bin that should be used to pack the compressed data in a data_vio with520 *                other data_vios.521 * @packer: The packer.522 * @data_vio: The data_vio.523 */524static struct packer_bin * __must_check select_bin(struct packer *packer,525						   struct data_vio *data_vio)526{527	/*528	 * First best fit: select the bin with the least free space that has enough room for the529	 * compressed data in the data_vio.530	 */531	struct packer_bin *bin, *fullest_bin;532 533	list_for_each_entry(bin, &packer->bins, list) {534		if (bin->free_space >= data_vio->compression.size)535			return bin;536	}537 538	/*539	 * None of the bins have enough space for the data_vio. We're not allowed to create new540	 * bins, so we have to overflow one of the existing bins. It's pretty intuitive to select541	 * the fullest bin, since that "wastes" the least amount of free space in the compressed542	 * block. But if the space currently used in the fullest bin is smaller than the compressed543	 * size of the incoming block, it seems wrong to force that bin to write when giving up on544	 * compressing the incoming data_vio would likewise "waste" the least amount of free space.545	 */546	fullest_bin = list_first_entry(&packer->bins, struct packer_bin, list);547	if (data_vio->compression.size >=548	    (VDO_COMPRESSED_BLOCK_DATA_SIZE - fullest_bin->free_space))549		return NULL;550 551	/*552	 * The fullest bin doesn't have room, but writing it out and starting a new batch with the553	 * incoming data_vio will increase the packer's free space.554	 */555	return fullest_bin;556}557 558/**559 * vdo_attempt_packing() - Attempt to rewrite the data in this data_vio as part of a compressed560 *                         block.561 * @data_vio: The data_vio to pack.562 */563void vdo_attempt_packing(struct data_vio *data_vio)564{565	int result;566	struct packer_bin *bin;567	struct data_vio_compression_status status = get_data_vio_compression_status(data_vio);568	struct packer *packer = get_packer_from_data_vio(data_vio);569 570	assert_on_packer_thread(packer, __func__);571 572	result = VDO_ASSERT((status.stage == DATA_VIO_COMPRESSING),573			    "attempt to pack data_vio not ready for packing, stage: %u",574			    status.stage);575	if (result != VDO_SUCCESS)576		return;577 578	/*579	 * Increment whether or not this data_vio will be packed or not since abort_packing()580	 * always decrements the counter.581	 */582	WRITE_ONCE(packer->statistics.compressed_fragments_in_packer,583		   packer->statistics.compressed_fragments_in_packer + 1);584 585	/*586	 * If packing of this data_vio is disallowed for administrative reasons, give up before587	 * making any state changes.588	 */589	if (!vdo_is_state_normal(&packer->state) ||590	    (data_vio->flush_generation < packer->flush_generation)) {591		abort_packing(data_vio);592		return;593	}594 595	/*596	 * The advance_data_vio_compression_stage() check here verifies that the data_vio is597	 * allowed to be compressed (if it has already been canceled, we'll fall out here). Once598	 * the data_vio is in the DATA_VIO_PACKING state, it must be guaranteed to be put in a bin599	 * before any more requests can be processed by the packer thread. Otherwise, a canceling600	 * data_vio could attempt to remove the canceled data_vio from the packer and fail to601	 * rendezvous with it. Thus, we must call select_bin() first to ensure that we will602	 * actually add the data_vio to a bin before advancing to the DATA_VIO_PACKING stage.603	 */604	bin = select_bin(packer, data_vio);605	if ((bin == NULL) ||606	    (advance_data_vio_compression_stage(data_vio).stage != DATA_VIO_PACKING)) {607		abort_packing(data_vio);608		return;609	}610 611	add_data_vio_to_packer_bin(packer, bin, data_vio);612}613 614/**615 * check_for_drain_complete() - Check whether the packer has drained.616 * @packer: The packer.617 */618static void check_for_drain_complete(struct packer *packer)619{620	if (vdo_is_state_draining(&packer->state) && (packer->canceled_bin->slots_used == 0))621		vdo_finish_draining(&packer->state);622}623 624/**625 * write_all_non_empty_bins() - Write out all non-empty bins on behalf of a flush or suspend.626 * @packer: The packer being flushed.627 */628static void write_all_non_empty_bins(struct packer *packer)629{630	struct packer_bin *bin;631 632	list_for_each_entry(bin, &packer->bins, list)633		write_bin(packer, bin);634		/*635		 * We don't need to re-sort the bin here since this loop will make every bin have636		 * the same amount of free space, so every ordering is sorted.637		 */638 639	check_for_drain_complete(packer);640}641 642/**643 * vdo_flush_packer() - Request that the packer flush asynchronously.644 * @packer: The packer to flush.645 *646 * All bins with at least two compressed data blocks will be written out, and any solitary pending647 * VIOs will be released from the packer. While flushing is in progress, any VIOs submitted to648 * vdo_attempt_packing() will be continued immediately without attempting to pack them.649 */650void vdo_flush_packer(struct packer *packer)651{652	assert_on_packer_thread(packer, __func__);653	if (vdo_is_state_normal(&packer->state))654		write_all_non_empty_bins(packer);655}656 657/**658 * vdo_remove_lock_holder_from_packer() - Remove a lock holder from the packer.659 * @completion: The data_vio which needs a lock held by a data_vio in the packer. The data_vio's660 *              compression.lock_holder field will point to the data_vio to remove.661 */662void vdo_remove_lock_holder_from_packer(struct vdo_completion *completion)663{664	struct data_vio *data_vio = as_data_vio(completion);665	struct packer *packer = get_packer_from_data_vio(data_vio);666	struct data_vio *lock_holder;667	struct packer_bin *bin;668	slot_number_t slot;669 670	assert_data_vio_in_packer_zone(data_vio);671 672	lock_holder = vdo_forget(data_vio->compression.lock_holder);673	bin = lock_holder->compression.bin;674	VDO_ASSERT_LOG_ONLY((bin != NULL), "data_vio in packer has a bin");675 676	slot = lock_holder->compression.slot;677	bin->slots_used--;678	if (slot < bin->slots_used) {679		bin->incoming[slot] = bin->incoming[bin->slots_used];680		bin->incoming[slot]->compression.slot = slot;681	}682 683	lock_holder->compression.bin = NULL;684	lock_holder->compression.slot = 0;685 686	if (bin != packer->canceled_bin) {687		bin->free_space += lock_holder->compression.size;688		insert_in_sorted_list(packer, bin);689	}690 691	abort_packing(lock_holder);692	check_for_drain_complete(packer);693}694 695/**696 * vdo_increment_packer_flush_generation() - Increment the flush generation in the packer.697 * @packer: The packer.698 *699 * This will also cause the packer to flush so that any VIOs from previous generations will exit700 * the packer.701 */702void vdo_increment_packer_flush_generation(struct packer *packer)703{704	assert_on_packer_thread(packer, __func__);705	packer->flush_generation++;706	vdo_flush_packer(packer);707}708 709/**710 * initiate_drain() - Initiate a drain.711 *712 * Implements vdo_admin_initiator_fn.713 */714static void initiate_drain(struct admin_state *state)715{716	struct packer *packer = container_of(state, struct packer, state);717 718	write_all_non_empty_bins(packer);719}720 721/**722 * vdo_drain_packer() - Drain the packer by preventing any more VIOs from entering the packer and723 *                      then flushing.724 * @packer: The packer to drain.725 * @completion: The completion to finish when the packer has drained.726 */727void vdo_drain_packer(struct packer *packer, struct vdo_completion *completion)728{729	assert_on_packer_thread(packer, __func__);730	vdo_start_draining(&packer->state, VDO_ADMIN_STATE_SUSPENDING, completion,731			   initiate_drain);732}733 734/**735 * vdo_resume_packer() - Resume a packer which has been suspended.736 * @packer: The packer to resume.737 * @parent: The completion to finish when the packer has resumed.738 */739void vdo_resume_packer(struct packer *packer, struct vdo_completion *parent)740{741	assert_on_packer_thread(packer, __func__);742	vdo_continue_completion(parent, vdo_resume_if_quiescent(&packer->state));743}744 745static void dump_packer_bin(const struct packer_bin *bin, bool canceled)746{747	if (bin->slots_used == 0)748		/* Don't dump empty bins. */749		return;750 751	vdo_log_info("	  %sBin slots_used=%u free_space=%zu",752		     (canceled ? "Canceled" : ""), bin->slots_used, bin->free_space);753 754	/*755	 * FIXME: dump vios in bin->incoming? The vios should have been dumped from the vio pool.756	 * Maybe just dump their addresses so it's clear they're here?757	 */758}759 760/**761 * vdo_dump_packer() - Dump the packer.762 * @packer: The packer.763 *764 * Context: dumps in a thread-unsafe fashion.765 */766void vdo_dump_packer(const struct packer *packer)767{768	struct packer_bin *bin;769 770	vdo_log_info("packer");771	vdo_log_info("	flushGeneration=%llu state %s  packer_bin_count=%llu",772		     (unsigned long long) packer->flush_generation,773		     vdo_get_admin_state_code(&packer->state)->name,774		     (unsigned long long) packer->size);775 776	list_for_each_entry(bin, &packer->bins, list)777		dump_packer_bin(bin, false);778 779	dump_packer_bin(packer->canceled_bin, true);780}781