diff options
Diffstat (limited to 'drivers/md/dm-vdo/repair.c')
| -rw-r--r-- | drivers/md/dm-vdo/repair.c | 1756 |
1 files changed, 1756 insertions, 0 deletions
diff --git a/drivers/md/dm-vdo/repair.c b/drivers/md/dm-vdo/repair.c new file mode 100644 index 0000000000..defc9359f1 --- /dev/null +++ b/drivers/md/dm-vdo/repair.c @@ -0,0 +1,1756 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2023 Red Hat + */ + +#include "repair.h" + +#include <linux/min_heap.h> +#include <linux/minmax.h> + +#include "logger.h" +#include "memory-alloc.h" +#include "permassert.h" + +#include "block-map.h" +#include "completion.h" +#include "constants.h" +#include "encodings.h" +#include "int-map.h" +#include "io-submitter.h" +#include "recovery-journal.h" +#include "slab-depot.h" +#include "types.h" +#include "vdo.h" +#include "wait-queue.h" + +/* + * An explicitly numbered block mapping. Numbering the mappings allows them to be sorted by logical + * block number during repair while still preserving the relative order of journal entries with + * the same logical block number. + */ +struct numbered_block_mapping { + struct block_map_slot block_map_slot; + struct block_map_entry block_map_entry; + /* A serial number to use during replay */ + u32 number; +} __packed; + +/* + * The absolute position of an entry in the recovery journal, including the sector number and the + * entry number within the sector. + */ +struct recovery_point { + /* Block sequence number */ + sequence_number_t sequence_number; + /* Sector number */ + u8 sector_count; + /* Entry number */ + journal_entry_count_t entry_count; + /* Whether or not the increment portion of the current entry has been applied */ + bool increment_applied; +}; + +struct repair_completion { + /* The completion header */ + struct vdo_completion completion; + + /* A buffer to hold the data read off disk */ + char *journal_data; + + /* For loading the journal */ + data_vio_count_t vio_count; + data_vio_count_t vios_complete; + struct vio *vios; + + /* The number of entries to be applied to the block map */ + size_t block_map_entry_count; + /* The sequence number of the first valid block for block map recovery */ + sequence_number_t block_map_head; + /* The sequence number of the first valid block for slab journal replay */ + sequence_number_t slab_journal_head; + /* The sequence number of the last valid block of the journal (if known) */ + sequence_number_t tail; + /* + * The highest sequence number of the journal. During recovery (vs read-only rebuild), not + * the same as the tail, since the tail ignores blocks after the first hole. + */ + sequence_number_t highest_tail; + + /* The number of logical blocks currently known to be in use */ + block_count_t logical_blocks_used; + /* The number of block map data blocks known to be allocated */ + block_count_t block_map_data_blocks; + + /* These fields are for playing the journal into the block map */ + /* The entry data for the block map recovery */ + struct numbered_block_mapping *entries; + /* The number of entries in the entry array */ + size_t entry_count; + /* number of pending (non-ready) requests*/ + page_count_t outstanding; + /* number of page completions */ + page_count_t page_count; + bool launching; + /* + * a heap wrapping journal_entries. It re-orders and sorts journal entries in ascending LBN + * order, then original journal order. This permits efficient iteration over the journal + * entries in order. + */ + struct min_heap replay_heap; + /* Fields tracking progress through the journal entries. */ + struct numbered_block_mapping *current_entry; + struct numbered_block_mapping *current_unfetched_entry; + /* Current requested page's PBN */ + physical_block_number_t pbn; + + /* These fields are only used during recovery. */ + /* A location just beyond the last valid entry of the journal */ + struct recovery_point tail_recovery_point; + /* The location of the next recovery journal entry to apply */ + struct recovery_point next_recovery_point; + /* The journal point to give to the next synthesized decref */ + struct journal_point next_journal_point; + /* The number of entries played into slab journals */ + size_t entries_added_to_slab_journals; + + /* These fields are only used during read-only rebuild */ + page_count_t page_to_fetch; + /* the number of leaf pages in the block map */ + page_count_t leaf_pages; + /* the last slot of the block map */ + struct block_map_slot last_slot; + + /* + * The page completions used for playing the journal into the block map, and, during + * read-only rebuild, for rebuilding the reference counts from the block map. + */ + struct vdo_page_completion page_completions[]; +}; + +/* + * This is a min_heap callback function that orders numbered_block_mappings using the + * 'block_map_slot' field as the primary key and the mapping 'number' field as the secondary key. + * Using the mapping number preserves the journal order of entries for the same slot, allowing us + * to sort by slot while still ensuring we replay all entries with the same slot in the exact order + * as they appeared in the journal. + */ +static bool mapping_is_less_than(const void *item1, const void *item2) +{ + const struct numbered_block_mapping *mapping1 = + (const struct numbered_block_mapping *) item1; + const struct numbered_block_mapping *mapping2 = + (const struct numbered_block_mapping *) item2; + + if (mapping1->block_map_slot.pbn != mapping2->block_map_slot.pbn) + return mapping1->block_map_slot.pbn < mapping2->block_map_slot.pbn; + + if (mapping1->block_map_slot.slot != mapping2->block_map_slot.slot) + return mapping1->block_map_slot.slot < mapping2->block_map_slot.slot; + + if (mapping1->number != mapping2->number) + return mapping1->number < mapping2->number; + + return 0; +} + +static void swap_mappings(void *item1, void *item2) +{ + struct numbered_block_mapping *mapping1 = item1; + struct numbered_block_mapping *mapping2 = item2; + + swap(*mapping1, *mapping2); +} + +static const struct min_heap_callbacks repair_min_heap = { + .elem_size = sizeof(struct numbered_block_mapping), + .less = mapping_is_less_than, + .swp = swap_mappings, +}; + +static struct numbered_block_mapping *sort_next_heap_element(struct repair_completion *repair) +{ + struct min_heap *heap = &repair->replay_heap; + struct numbered_block_mapping *last; + + if (heap->nr == 0) + return NULL; + + /* + * Swap the next heap element with the last one on the heap, popping it off the heap, + * restore the heap invariant, and return a pointer to the popped element. + */ + last = &repair->entries[--heap->nr]; + swap_mappings(heap->data, last); + min_heapify(heap, 0, &repair_min_heap); + return last; +} + +/** + * as_repair_completion() - Convert a generic completion to a repair_completion. + * @completion: The completion to convert. + * + * Return: The repair_completion. + */ +static inline struct repair_completion * __must_check +as_repair_completion(struct vdo_completion *completion) +{ + vdo_assert_completion_type(completion, VDO_REPAIR_COMPLETION); + return container_of(completion, struct repair_completion, completion); +} + +static void prepare_repair_completion(struct repair_completion *repair, + vdo_action_fn callback, enum vdo_zone_type zone_type) +{ + struct vdo_completion *completion = &repair->completion; + const struct thread_config *thread_config = &completion->vdo->thread_config; + thread_id_t thread_id; + + /* All blockmap access is done on single thread, so use logical zone 0. */ + thread_id = ((zone_type == VDO_ZONE_TYPE_LOGICAL) ? + thread_config->logical_threads[0] : + thread_config->admin_thread); + vdo_reset_completion(completion); + vdo_set_completion_callback(completion, callback, thread_id); +} + +static void launch_repair_completion(struct repair_completion *repair, + vdo_action_fn callback, enum vdo_zone_type zone_type) +{ + prepare_repair_completion(repair, callback, zone_type); + vdo_launch_completion(&repair->completion); +} + +static void uninitialize_vios(struct repair_completion *repair) +{ + while (repair->vio_count > 0) + free_vio_components(&repair->vios[--repair->vio_count]); + + vdo_free(vdo_forget(repair->vios)); +} + +static void free_repair_completion(struct repair_completion *repair) +{ + if (repair == NULL) + return; + + /* + * We do this here because this function is the only common bottleneck for all clean up + * paths. + */ + repair->completion.vdo->block_map->zones[0].page_cache.rebuilding = false; + + uninitialize_vios(repair); + vdo_free(vdo_forget(repair->journal_data)); + vdo_free(vdo_forget(repair->entries)); + vdo_free(repair); +} + +static void finish_repair(struct vdo_completion *completion) +{ + struct vdo_completion *parent = completion->parent; + struct vdo *vdo = completion->vdo; + struct repair_completion *repair = as_repair_completion(completion); + + vdo_assert_on_admin_thread(vdo, __func__); + + if (vdo->load_state != VDO_REBUILD_FOR_UPGRADE) + vdo->states.vdo.complete_recoveries++; + + vdo_initialize_recovery_journal_post_repair(vdo->recovery_journal, + vdo->states.vdo.complete_recoveries, + repair->highest_tail, + repair->logical_blocks_used, + repair->block_map_data_blocks); + free_repair_completion(vdo_forget(repair)); + + if (vdo_state_requires_read_only_rebuild(vdo->load_state)) { + vdo_log_info("Read-only rebuild complete"); + vdo_launch_completion(parent); + return; + } + + /* FIXME: shouldn't this say either "recovery" or "repair"? */ + vdo_log_info("Rebuild complete"); + + /* + * Now that we've freed the repair completion and its vast array of journal entries, we + * can allocate refcounts. + */ + vdo_continue_completion(parent, vdo_allocate_reference_counters(vdo->depot)); +} + +/** + * abort_repair() - Handle a repair error. + * @completion: The repair completion. + */ +static void abort_repair(struct vdo_completion *completion) +{ + struct vdo_completion *parent = completion->parent; + int result = completion->result; + struct repair_completion *repair = as_repair_completion(completion); + + if (vdo_state_requires_read_only_rebuild(completion->vdo->load_state)) + vdo_log_info("Read-only rebuild aborted"); + else + vdo_log_warning("Recovery aborted"); + + free_repair_completion(vdo_forget(repair)); + vdo_continue_completion(parent, result); +} + +/** + * abort_on_error() - Abort a repair if there is an error. + * @result: The result to check. + * @repair: The repair completion. + * + * Return: true if the result was an error. + */ +static bool __must_check abort_on_error(int result, struct repair_completion *repair) +{ + if (result == VDO_SUCCESS) + return false; + + vdo_fail_completion(&repair->completion, result); + return true; +} + +/** + * drain_slab_depot() - Flush out all dirty refcounts blocks now that they have been rebuilt or + * recovered. + */ +static void drain_slab_depot(struct vdo_completion *completion) +{ + struct vdo *vdo = completion->vdo; + struct repair_completion *repair = as_repair_completion(completion); + const struct admin_state_code *operation; + + vdo_assert_on_admin_thread(vdo, __func__); + + prepare_repair_completion(repair, finish_repair, VDO_ZONE_TYPE_ADMIN); + if (vdo_state_requires_read_only_rebuild(vdo->load_state)) { + vdo_log_info("Saving rebuilt state"); + operation = VDO_ADMIN_STATE_REBUILDING; + } else { + vdo_log_info("Replayed %zu journal entries into slab journals", + repair->entries_added_to_slab_journals); + operation = VDO_ADMIN_STATE_RECOVERING; + } + + vdo_drain_slab_depot(vdo->depot, operation, completion); +} + +/** + * flush_block_map_updates() - Flush the block map now that all the reference counts are rebuilt. + * @completion: The repair completion. + * + * This callback is registered in finish_if_done(). + */ +static void flush_block_map_updates(struct vdo_completion *completion) +{ + vdo_assert_on_admin_thread(completion->vdo, __func__); + + vdo_log_info("Flushing block map changes"); + prepare_repair_completion(as_repair_completion(completion), drain_slab_depot, + VDO_ZONE_TYPE_ADMIN); + vdo_drain_block_map(completion->vdo->block_map, VDO_ADMIN_STATE_RECOVERING, + completion); +} + +static bool fetch_page(struct repair_completion *repair, + struct vdo_completion *completion); + +/** + * handle_page_load_error() - Handle an error loading a page. + * @completion: The vdo_page_completion. + */ +static void handle_page_load_error(struct vdo_completion *completion) +{ + struct repair_completion *repair = completion->parent; + + repair->outstanding--; + vdo_set_completion_result(&repair->completion, completion->result); + vdo_release_page_completion(completion); + fetch_page(repair, completion); +} + +/** + * unmap_entry() - Unmap an invalid entry and indicate that its page must be written out. + * @page: The page containing the entries + * @completion: The page_completion for writing the page + * @slot: The slot to unmap + */ +static void unmap_entry(struct block_map_page *page, struct vdo_completion *completion, + slot_number_t slot) +{ + page->entries[slot] = UNMAPPED_BLOCK_MAP_ENTRY; + vdo_request_page_write(completion); +} + +/** + * remove_out_of_bounds_entries() - Unmap entries which outside the logical space. + * @page: The page containing the entries + * @completion: The page_completion for writing the page + * @start: The first slot to check + */ +static void remove_out_of_bounds_entries(struct block_map_page *page, + struct vdo_completion *completion, + slot_number_t start) +{ + slot_number_t slot; + + for (slot = start; slot < VDO_BLOCK_MAP_ENTRIES_PER_PAGE; slot++) { + struct data_location mapping = vdo_unpack_block_map_entry(&page->entries[slot]); + + if (vdo_is_mapped_location(&mapping)) + unmap_entry(page, completion, slot); + } +} + +/** + * process_slot() - Update the reference counts for a single entry. + * @page: The page containing the entries + * @completion: The page_completion for writing the page + * @slot: The slot to check + * + * Return: true if the entry was a valid mapping + */ +static bool process_slot(struct block_map_page *page, struct vdo_completion *completion, + slot_number_t slot) +{ + struct slab_depot *depot = completion->vdo->depot; + int result; + struct data_location mapping = vdo_unpack_block_map_entry(&page->entries[slot]); + + if (!vdo_is_valid_location(&mapping)) { + /* This entry is invalid, so remove it from the page. */ + unmap_entry(page, completion, slot); + return false; + } + + if (!vdo_is_mapped_location(&mapping)) + return false; + + + if (mapping.pbn == VDO_ZERO_BLOCK) + return true; + + if (!vdo_is_physical_data_block(depot, mapping.pbn)) { + /* + * This is a nonsense mapping. Remove it from the map so we're at least consistent + * and mark the page dirty. + */ + unmap_entry(page, completion, slot); + return false; + } + + result = vdo_adjust_reference_count_for_rebuild(depot, mapping.pbn, + VDO_JOURNAL_DATA_REMAPPING); + if (result == VDO_SUCCESS) + return true; + + vdo_log_error_strerror(result, + "Could not adjust reference count for PBN %llu, slot %u mapped to PBN %llu", + (unsigned long long) vdo_get_block_map_page_pbn(page), + slot, (unsigned long long) mapping.pbn); + unmap_entry(page, completion, slot); + return false; +} + +/** + * rebuild_reference_counts_from_page() - Rebuild reference counts from a block map page. + * @repair: The repair completion. + * @completion: The page completion holding the page. + */ +static void rebuild_reference_counts_from_page(struct repair_completion *repair, + struct vdo_completion *completion) +{ + slot_number_t slot, last_slot; + struct block_map_page *page; + int result; + + result = vdo_get_cached_page(completion, &page); + if (result != VDO_SUCCESS) { + vdo_set_completion_result(&repair->completion, result); + return; + } + + if (!page->header.initialized) + return; + + /* Remove any bogus entries which exist beyond the end of the logical space. */ + if (vdo_get_block_map_page_pbn(page) == repair->last_slot.pbn) { + last_slot = repair->last_slot.slot; + remove_out_of_bounds_entries(page, completion, last_slot); + } else { + last_slot = VDO_BLOCK_MAP_ENTRIES_PER_PAGE; + } + + /* Inform the slab depot of all entries on this page. */ + for (slot = 0; slot < last_slot; slot++) { + if (process_slot(page, completion, slot)) + repair->logical_blocks_used++; + } +} + +/** + * page_loaded() - Process a page which has just been loaded. + * @completion: The vdo_page_completion for the fetched page. + * + * This callback is registered by fetch_page(). + */ +static void page_loaded(struct vdo_completion *completion) +{ + struct repair_completion *repair = completion->parent; + + repair->outstanding--; + rebuild_reference_counts_from_page(repair, completion); + vdo_release_page_completion(completion); + + /* Advance progress to the next page, and fetch the next page we haven't yet requested. */ + fetch_page(repair, completion); +} + +static physical_block_number_t get_pbn_to_fetch(struct repair_completion *repair, + struct block_map *block_map) +{ + physical_block_number_t pbn = VDO_ZERO_BLOCK; + + if (repair->completion.result != VDO_SUCCESS) + return VDO_ZERO_BLOCK; + + while ((pbn == VDO_ZERO_BLOCK) && (repair->page_to_fetch < repair->leaf_pages)) + pbn = vdo_find_block_map_page_pbn(block_map, repair->page_to_fetch++); + + if (vdo_is_physical_data_block(repair->completion.vdo->depot, pbn)) + return pbn; + + vdo_set_completion_result(&repair->completion, VDO_BAD_MAPPING); + return VDO_ZERO_BLOCK; +} + +/** + * fetch_page() - Fetch a page from the block map. + * @repair: The repair_completion. + * @completion: The page completion to use. + * + * Return true if the rebuild is complete + */ +static bool fetch_page(struct repair_completion *repair, + struct vdo_completion *completion) +{ + struct vdo_page_completion *page_completion = (struct vdo_page_completion *) completion; + struct block_map *block_map = repair->completion.vdo->block_map; + physical_block_number_t pbn = get_pbn_to_fetch(repair, block_map); + + if (pbn != VDO_ZERO_BLOCK) { + repair->outstanding++; + /* + * We must set the requeue flag here to ensure that we don't blow the stack if all + * the requested pages are already in the cache or get load errors. + */ + vdo_get_page(page_completion, &block_map->zones[0], pbn, true, repair, + page_loaded, handle_page_load_error, true); + } + + if (repair->outstanding > 0) + return false; + + launch_repair_completion(repair, flush_block_map_updates, VDO_ZONE_TYPE_ADMIN); + return true; +} + +/** + * rebuild_from_leaves() - Rebuild reference counts from the leaf block map pages. + * @completion: The repair completion. + * + * Rebuilds reference counts from the leaf block map pages now that reference counts have been + * rebuilt from the interior tree pages (which have been loaded in the process). This callback is + * registered in rebuild_reference_counts(). + */ +static void rebuild_from_leaves(struct vdo_completion *completion) +{ + page_count_t i; + struct repair_completion *repair = as_repair_completion(completion); + struct block_map *map = completion->vdo->block_map; + + repair->logical_blocks_used = 0; + + /* + * The PBN calculation doesn't work until the tree pages have been loaded, so we can't set + * this value at the start of repair. + */ + repair->leaf_pages = vdo_compute_block_map_page_count(map->entry_count); + repair->last_slot = (struct block_map_slot) { + .slot = map->entry_count % VDO_BLOCK_MAP_ENTRIES_PER_PAGE, + .pbn = vdo_find_block_map_page_pbn(map, repair->leaf_pages - 1), + }; + if (repair->last_slot.slot == 0) + repair->last_slot.slot = VDO_BLOCK_MAP_ENTRIES_PER_PAGE; + + for (i = 0; i < repair->page_count; i++) { + if (fetch_page(repair, &repair->page_completions[i].completion)) { + /* + * The rebuild has already moved on, so it isn't safe nor is there a need + * to launch any more fetches. + */ + return; + } + } +} + +/** + * process_entry() - Process a single entry from the block map tree. + * @pbn: A pbn which holds a block map tree page. + * @completion: The parent completion of the traversal. + * + * Implements vdo_entry_callback_fn. + * + * Return: VDO_SUCCESS or an error. + */ +static int process_entry(physical_block_number_t pbn, struct vdo_completion *completion) +{ + struct repair_completion *repair = as_repair_completion(completion); + struct slab_depot *depot = completion->vdo->depot; + int result; + + if ((pbn == VDO_ZERO_BLOCK) || !vdo_is_physical_data_block(depot, pbn)) { + return vdo_log_error_strerror(VDO_BAD_CONFIGURATION, + "PBN %llu out of range", + (unsigned long long) pbn); + } + + result = vdo_adjust_reference_count_for_rebuild(depot, pbn, + VDO_JOURNAL_BLOCK_MAP_REMAPPING); + if (result != VDO_SUCCESS) { + return vdo_log_error_strerror(result, + "Could not adjust reference count for block map tree PBN %llu", + (unsigned long long) pbn); + } + + repair->block_map_data_blocks++; + return VDO_SUCCESS; +} + +static void rebuild_reference_counts(struct vdo_completion *completion) +{ + struct repair_completion *repair = as_repair_completion(completion); + struct vdo *vdo = completion->vdo; + struct vdo_page_cache *cache = &vdo->block_map->zones[0].page_cache; + + /* We must allocate ref_counts before we can rebuild them. */ + if (abort_on_error(vdo_allocate_reference_counters(vdo->depot), repair)) + return; + + /* + * Completion chaining from page cache hits can lead to stack overflow during the rebuild, + * so clear out the cache before this rebuild phase. + */ + if (abort_on_error(vdo_invalidate_page_cache(cache), repair)) + return; + + prepare_repair_completion(repair, rebuild_from_leaves, VDO_ZONE_TYPE_LOGICAL); + vdo_traverse_forest(vdo->block_map, process_entry, completion); +} + +/** + * increment_recovery_point() - Move the given recovery point forward by one entry. + */ +static void increment_recovery_point(struct recovery_point *point) +{ + if (++point->entry_count < RECOVERY_JOURNAL_ENTRIES_PER_SECTOR) + return; + + point->entry_count = 0; + if (point->sector_count < (VDO_SECTORS_PER_BLOCK - 1)) { + point->sector_count++; + return; + } + + point->sequence_number++; + point->sector_count = 1; +} + +/** + * advance_points() - Advance the current recovery and journal points. + * @repair: The repair_completion whose points are to be advanced. + * @entries_per_block: The number of entries in a recovery journal block. + */ +static void advance_points(struct repair_completion *repair, + journal_entry_count_t entries_per_block) +{ + if (!repair->next_recovery_point.increment_applied) { + repair->next_recovery_point.increment_applied = true; + return; + } + + increment_recovery_point(&repair->next_recovery_point); + vdo_advance_journal_point(&repair->next_journal_point, entries_per_block); + repair->next_recovery_point.increment_applied = false; +} + +/** + * before_recovery_point() - Check whether the first point precedes the second point. + * @first: The first recovery point. + * @second: The second recovery point. + * + * Return: true if the first point precedes the second point. + */ +static bool __must_check before_recovery_point(const struct recovery_point *first, + const struct recovery_point *second) +{ + if (first->sequence_number < second->sequence_number) + return true; + + if (first->sequence_number > second->sequence_number) + return false; + + if (first->sector_count < second->sector_count) + return true; + + return ((first->sector_count == second->sector_count) && + (first->entry_count < second->entry_count)); +} + +static struct packed_journal_sector * __must_check get_sector(struct recovery_journal *journal, + char *journal_data, + sequence_number_t sequence, + u8 sector_number) +{ + off_t offset; + + offset = ((vdo_get_recovery_journal_block_number(journal, sequence) * VDO_BLOCK_SIZE) + + (VDO_SECTOR_SIZE * sector_number)); + return (struct packed_journal_sector *) (journal_data + offset); +} + +/** + * get_entry() - Unpack the recovery journal entry associated with the given recovery point. + * @repair: The repair completion. + * @point: The recovery point. + * + * Return: The unpacked contents of the matching recovery journal entry. + */ +static struct recovery_journal_entry get_entry(const struct repair_completion *repair, + const struct recovery_point *point) +{ + struct packed_journal_sector *sector; + + sector = get_sector(repair->completion.vdo->recovery_journal, + repair->journal_data, point->sequence_number, + point->sector_count); + return vdo_unpack_recovery_journal_entry(§or->entries[point->entry_count]); +} + +/** + * validate_recovery_journal_entry() - Validate a recovery journal entry. + * @vdo: The vdo. + * @entry: The entry to validate. + * + * Return: VDO_SUCCESS or an error. + */ +static int validate_recovery_journal_entry(const struct vdo *vdo, + const struct recovery_journal_entry *entry) +{ + if ((entry->slot.pbn >= vdo->states.vdo.config.physical_blocks) || + (entry->slot.slot >= VDO_BLOCK_MAP_ENTRIES_PER_PAGE) || + !vdo_is_valid_location(&entry->mapping) || + !vdo_is_valid_location(&entry->unmapping) || + !vdo_is_physical_data_block(vdo->depot, entry->mapping.pbn) || + !vdo_is_physical_data_block(vdo->depot, entry->unmapping.pbn)) { + return vdo_log_error_strerror(VDO_CORRUPT_JOURNAL, + "Invalid entry: %s (%llu, %u) from %llu to %llu is not within bounds", + vdo_get_journal_operation_name(entry->operation), + (unsigned long long) entry->slot.pbn, + entry->slot.slot, + (unsigned long long) entry->unmapping.pbn, + (unsigned long long) entry->mapping.pbn); + } + + if ((entry->operation == VDO_JOURNAL_BLOCK_MAP_REMAPPING) && + (vdo_is_state_compressed(entry->mapping.state) || + (entry->mapping.pbn == VDO_ZERO_BLOCK) || + (entry->unmapping.state != VDO_MAPPING_STATE_UNMAPPED) || + (entry->unmapping.pbn != VDO_ZERO_BLOCK))) { + return vdo_log_error_strerror(VDO_CORRUPT_JOURNAL, + "Invalid entry: %s (%llu, %u) from %llu to %llu is not a valid tree mapping", + vdo_get_journal_operation_name(entry->operation), + (unsigned long long) entry->slot.pbn, + entry->slot.slot, + (unsigned long long) entry->unmapping.pbn, + (unsigned long long) entry->mapping.pbn); + } + + return VDO_SUCCESS; +} + +/** + * add_slab_journal_entries() - Replay recovery journal entries into the slab journals of the + * allocator currently being recovered. + * @completion: The allocator completion. + * + * Waits for slab journal tailblock space when necessary. This method is its own callback. + */ +static void add_slab_journal_entries(struct vdo_completion *completion) +{ + struct recovery_point *recovery_point; + struct repair_completion *repair = completion->parent; + struct vdo *vdo = completion->vdo; + struct recovery_journal *journal = vdo->recovery_journal; + struct block_allocator *allocator = vdo_as_block_allocator(completion); + + /* Get ready in case we need to enqueue again. */ + vdo_prepare_completion(completion, add_slab_journal_entries, + vdo_notify_slab_journals_are_recovered, + completion->callback_thread_id, repair); + for (recovery_point = &repair->next_recovery_point; + before_recovery_point(recovery_point, &repair->tail_recovery_point); + advance_points(repair, journal->entries_per_block)) { + int result; + physical_block_number_t pbn; + struct vdo_slab *slab; + struct recovery_journal_entry entry = get_entry(repair, recovery_point); + bool increment = !repair->next_recovery_point.increment_applied; + + if (increment) { + result = validate_recovery_journal_entry(vdo, &entry); + if (result != VDO_SUCCESS) { + vdo_enter_read_only_mode(vdo, result); + vdo_fail_completion(completion, result); + return; + } + + pbn = entry.mapping.pbn; + } else { + pbn = entry.unmapping.pbn; + } + + if (pbn == VDO_ZERO_BLOCK) + continue; + + slab = vdo_get_slab(vdo->depot, pbn); + if (slab->allocator != allocator) + continue; + + if (!vdo_attempt_replay_into_slab(slab, pbn, entry.operation, increment, + &repair->next_journal_point, + completion)) + return; + + repair->entries_added_to_slab_journals++; + } + + vdo_notify_slab_journals_are_recovered(completion); +} + +/** + * vdo_replay_into_slab_journals() - Replay recovery journal entries in the slab journals of slabs + * owned by a given block_allocator. + * @allocator: The allocator whose slab journals are to be recovered. + * @context: The slab depot load context supplied by a recovery when it loads the depot. + */ +void vdo_replay_into_slab_journals(struct block_allocator *allocator, void *context) +{ + struct vdo_completion *completion = &allocator->completion; + struct repair_completion *repair = context; + struct vdo *vdo = completion->vdo; + + vdo_assert_on_physical_zone_thread(vdo, allocator->zone_number, __func__); + if (repair->entry_count == 0) { + /* there's nothing to replay */ + repair->logical_blocks_used = vdo->recovery_journal->logical_blocks_used; + repair->block_map_data_blocks = vdo->recovery_journal->block_map_data_blocks; + vdo_notify_slab_journals_are_recovered(completion); + return; + } + + repair->next_recovery_point = (struct recovery_point) { + .sequence_number = repair->slab_journal_head, + .sector_count = 1, + .entry_count = 0, + }; + + repair->next_journal_point = (struct journal_point) { + .sequence_number = repair->slab_journal_head, + .entry_count = 0, + }; + + vdo_log_info("Replaying entries into slab journals for zone %u", + allocator->zone_number); + completion->parent = repair; + add_slab_journal_entries(completion); +} + +static void load_slab_depot(struct vdo_completion *completion) +{ + struct repair_completion *repair = as_repair_completion(completion); + const struct admin_state_code *operation; + + vdo_assert_on_admin_thread(completion->vdo, __func__); + + if (vdo_state_requires_read_only_rebuild(completion->vdo->load_state)) { + prepare_repair_completion(repair, rebuild_reference_counts, + VDO_ZONE_TYPE_LOGICAL); + operation = VDO_ADMIN_STATE_LOADING_FOR_REBUILD; + } else { + prepare_repair_completion(repair, drain_slab_depot, VDO_ZONE_TYPE_ADMIN); + operation = VDO_ADMIN_STATE_LOADING_FOR_RECOVERY; + } + + vdo_load_slab_depot(completion->vdo->depot, operation, completion, repair); +} + +static void flush_block_map(struct vdo_completion *completion) +{ + struct repair_completion *repair = as_repair_completion(completion); + const struct admin_state_code *operation; + + vdo_assert_on_admin_thread(completion->vdo, __func__); + + vdo_log_info("Flushing block map changes"); + prepare_repair_completion(repair, load_slab_depot, VDO_ZONE_TYPE_ADMIN); + operation = (vdo_state_requires_read_only_rebuild(completion->vdo->load_state) ? + VDO_ADMIN_STATE_REBUILDING : + VDO_ADMIN_STATE_RECOVERING); + vdo_drain_block_map(completion->vdo->block_map, operation, completion); +} + +static bool finish_if_done(struct repair_completion *repair) +{ + /* Pages are still being launched or there is still work to do */ + if (repair->launching || (repair->outstanding > 0)) + return false; + + if (repair->completion.result != VDO_SUCCESS) { + page_count_t i; + + for (i = 0; i < repair->page_count; i++) { + struct vdo_page_completion *page_completion = + &repair->page_completions[i]; + + if (page_completion->ready) + vdo_release_page_completion(&page_completion->completion); + } + + vdo_launch_completion(&repair->completion); + return true; + } + + if (repair->current_entry >= repair->entries) + return false; + + launch_repair_completion(repair, flush_block_map, VDO_ZONE_TYPE_ADMIN); + return true; +} + +static void abort_block_map_recovery(struct repair_completion *repair, int result) +{ + vdo_set_completion_result(&repair->completion, result); + finish_if_done(repair); +} + +/** + * find_entry_starting_next_page() - Find the first journal entry after a given entry which is not + * on the same block map page. + * @current_entry: The entry to search from. + * @needs_sort: Whether sorting is needed to proceed. + * + * Return: Pointer to the first later journal entry on a different block map page, or a pointer to + * just before the journal entries if no subsequent entry is on a different block map page. + */ +static struct numbered_block_mapping * +find_entry_starting_next_page(struct repair_completion *repair, + struct numbered_block_mapping *current_entry, bool needs_sort) +{ + size_t current_page; + + /* If current_entry is invalid, return immediately. */ + if (current_entry < repair->entries) + return current_entry; + + current_page = current_entry->block_map_slot.pbn; + + /* Decrement current_entry until it's out of bounds or on a different page. */ + while ((current_entry >= repair->entries) && + (current_entry->block_map_slot.pbn == current_page)) { + if (needs_sort) { + struct numbered_block_mapping *just_sorted_entry = + sort_next_heap_element(repair); + VDO_ASSERT_LOG_ONLY(just_sorted_entry < current_entry, + "heap is returning elements in an unexpected order"); + } + + current_entry--; + } + + return current_entry; +} + +/* + * Apply a range of journal entries [starting_entry, ending_entry) journal + * entries to a block map page. + */ +static void apply_journal_entries_to_page(struct block_map_page *page, + struct numbered_block_mapping *starting_entry, + struct numbered_block_mapping *ending_entry) +{ + struct numbered_block_mapping *current_entry = starting_entry; + + while (current_entry != ending_entry) { + page->entries[current_entry->block_map_slot.slot] = current_entry->block_map_entry; + current_entry--; + } +} + +static void recover_ready_pages(struct repair_completion *repair, + struct vdo_completion *completion); + +static void block_map_page_loaded(struct vdo_completion *completion) +{ + struct repair_completion *repair = as_repair_completion(completion->parent); + + repair->outstanding--; + if (!repair->launching) + recover_ready_pages(repair, completion); +} + +static void handle_block_map_page_load_error(struct vdo_completion *completion) +{ + struct repair_completion *repair = as_repair_completion(completion->parent); + + repair->outstanding--; + abort_block_map_recovery(repair, completion->result); +} + +static void fetch_block_map_page(struct repair_completion *repair, + struct vdo_completion *completion) +{ + physical_block_number_t pbn; + + if (repair->current_unfetched_entry < repair->entries) + /* Nothing left to fetch. */ + return; + + /* Fetch the next page we haven't yet requested. */ + pbn = repair->current_unfetched_entry->block_map_slot.pbn; + repair->current_unfetched_entry = + find_entry_starting_next_page(repair, repair->current_unfetched_entry, + true); + repair->outstanding++; + vdo_get_page(((struct vdo_page_completion *) completion), + &repair->completion.vdo->block_map->zones[0], pbn, true, + &repair->completion, block_map_page_loaded, + handle_block_map_page_load_error, false); +} + +static struct vdo_page_completion *get_next_page_completion(struct repair_completion *repair, + struct vdo_page_completion *completion) +{ + completion++; + if (completion == (&repair->page_completions[repair->page_count])) + completion = &repair->page_completions[0]; + return completion; +} + +static void recover_ready_pages(struct repair_completion *repair, + struct vdo_completion *completion) +{ + struct vdo_page_completion *page_completion = (struct vdo_page_completion *) completion; + + if (finish_if_done(repair)) + return; + + if (repair->pbn != page_completion->pbn) + return; + + while (page_completion->ready) { + struct numbered_block_mapping *start_of_next_page; + struct block_map_page *page; + int result; + + result = vdo_get_cached_page(completion, &page); + if (result != VDO_SUCCESS) { + abort_block_map_recovery(repair, result); + return; + } + + start_of_next_page = + find_entry_starting_next_page(repair, repair->current_entry, + false); + apply_journal_entries_to_page(page, repair->current_entry, + start_of_next_page); + repair->current_entry = start_of_next_page; + vdo_request_page_write(completion); + vdo_release_page_completion(completion); + + if (finish_if_done(repair)) + return; + + repair->pbn = repair->current_entry->block_map_slot.pbn; + fetch_block_map_page(repair, completion); + page_completion = get_next_page_completion(repair, page_completion); + completion = &page_completion->completion; + } +} + +static void recover_block_map(struct vdo_completion *completion) +{ + struct repair_completion *repair = as_repair_completion(completion); + struct vdo *vdo = completion->vdo; + struct numbered_block_mapping *first_sorted_entry; + page_count_t i; + + vdo_assert_on_logical_zone_thread(vdo, 0, __func__); + + /* Suppress block map errors. */ + vdo->block_map->zones[0].page_cache.rebuilding = + vdo_state_requires_read_only_rebuild(vdo->load_state); + + if (repair->block_map_entry_count == 0) { + vdo_log_info("Replaying 0 recovery entries into block map"); + vdo_free(vdo_forget(repair->journal_data)); + launch_repair_completion(repair, load_slab_depot, VDO_ZONE_TYPE_ADMIN); + return; + } + + /* + * Organize the journal entries into a binary heap so we can iterate over them in sorted + * order incrementally, avoiding an expensive sort call. + */ + repair->replay_heap = (struct min_heap) { + .data = repair->entries, + .nr = repair->block_map_entry_count, + .size = repair->block_map_entry_count, + }; + min_heapify_all(&repair->replay_heap, &repair_min_heap); + + vdo_log_info("Replaying %zu recovery entries into block map", + repair->block_map_entry_count); + + repair->current_entry = &repair->entries[repair->block_map_entry_count - 1]; + first_sorted_entry = sort_next_heap_element(repair); + VDO_ASSERT_LOG_ONLY(first_sorted_entry == repair->current_entry, + "heap is returning elements in an unexpected order"); + + /* Prevent any page from being processed until all pages have been launched. */ + repair->launching = true; + repair->pbn = repair->current_entry->block_map_slot.pbn; + repair->current_unfetched_entry = repair->current_entry; + for (i = 0; i < repair->page_count; i++) { + if (repair->current_unfetched_entry < repair->entries) + break; + + fetch_block_map_page(repair, &repair->page_completions[i].completion); + } + repair->launching = false; + + /* Process any ready pages. */ + recover_ready_pages(repair, &repair->page_completions[0].completion); +} + +/** + * get_recovery_journal_block_header() - Get the block header for a block at a position in the + * journal data and unpack it. + * @journal: The recovery journal. + * @data: The recovery journal data. + * @sequence: The sequence number. + * + * Return: The unpacked header. + */ +static struct recovery_block_header __must_check +get_recovery_journal_block_header(struct recovery_journal *journal, char *data, + sequence_number_t sequence) +{ + physical_block_number_t pbn = + vdo_get_recovery_journal_block_number(journal, sequence); + char *header = &data[pbn * VDO_BLOCK_SIZE]; + + return vdo_unpack_recovery_block_header((struct packed_journal_header *) header); +} + +/** + * is_valid_recovery_journal_block() - Determine whether the given header describes a valid block + * for the given journal. + * @journal: The journal to use. + * @header: The unpacked block header to check. + * @old_ok: Whether an old format header is valid. + * + * A block is not valid if it is unformatted, or if it is older than the last successful recovery + * or reformat. + * + * Return: True if the header is valid. + */ +static bool __must_check is_valid_recovery_journal_block(const struct recovery_journal *journal, + const struct recovery_block_header *header, + bool old_ok) +{ + if ((header->nonce != journal->nonce) || + (header->recovery_count != journal->recovery_count)) + return false; + + if (header->metadata_type == VDO_METADATA_RECOVERY_JOURNAL_2) + return (header->entry_count <= journal->entries_per_block); + + return (old_ok && + (header->metadata_type == VDO_METADATA_RECOVERY_JOURNAL) && + (header->entry_count <= RECOVERY_JOURNAL_1_ENTRIES_PER_BLOCK)); +} + +/** + * is_exact_recovery_journal_block() - Determine whether the given header describes the exact block + * indicated. + * @journal: The journal to use. + * @header: The unpacked block header to check. + * @sequence: The expected sequence number. + * @type: The expected metadata type. + * + * Return: True if the block matches. + */ +static bool __must_check is_exact_recovery_journal_block(const struct recovery_journal *journal, + const struct recovery_block_header *header, + sequence_number_t sequence, + enum vdo_metadata_type type) +{ + return ((header->metadata_type == type) && + (header->sequence_number == sequence) && + (is_valid_recovery_journal_block(journal, header, true))); +} + +/** + * find_recovery_journal_head_and_tail() - Find the tail and head of the journal. + * + * Return: True if there were valid journal blocks. + */ +static bool find_recovery_journal_head_and_tail(struct repair_completion *repair) +{ + struct recovery_journal *journal = repair->completion.vdo->recovery_journal; + bool found_entries = false; + physical_block_number_t i; + + /* + * Ensure that we don't replay old entries since we know the tail recorded in the super + * block must be a lower bound. Not doing so can result in extra data loss by setting the + * tail too early. + */ + repair->highest_tail = journal->tail; + for (i = 0; i < journal->size; i++) { + struct recovery_block_header header = + get_recovery_journal_block_header(journal, repair->journal_data, i); + + if (!is_valid_recovery_journal_block(journal, &header, true)) { + /* This block is old or incorrectly formatted */ + continue; + } + + if (vdo_get_recovery_journal_block_number(journal, header.sequence_number) != i) { + /* This block is in the wrong location */ + continue; + } + + if (header.sequence_number >= repair->highest_tail) { + found_entries = true; + repair->highest_tail = header.sequence_number; + } + + if (!found_entries) + continue; + + if (header.block_map_head > repair->block_map_head) + repair->block_map_head = header.block_map_head; + + if (header.slab_journal_head > repair->slab_journal_head) + repair->slab_journal_head = header.slab_journal_head; + } + + return found_entries; +} + +/** + * unpack_entry() - Unpack a recovery journal entry in either format. + * @vdo: The vdo. + * @packed: The entry to unpack. + * @format: The expected format of the entry. + * @entry: The unpacked entry. + * + * Return: true if the entry should be applied.3 + */ +static bool unpack_entry(struct vdo *vdo, char *packed, enum vdo_metadata_type format, + struct recovery_journal_entry *entry) +{ + if (format == VDO_METADATA_RECOVERY_JOURNAL_2) { + struct packed_recovery_journal_entry *packed_entry = + (struct packed_recovery_journal_entry *) packed; + + *entry = vdo_unpack_recovery_journal_entry(packed_entry); + } else { + physical_block_number_t low32, high4; + + struct packed_recovery_journal_entry_1 *packed_entry = + (struct packed_recovery_journal_entry_1 *) packed; + + if (packed_entry->operation == VDO_JOURNAL_DATA_INCREMENT) + entry->operation = VDO_JOURNAL_DATA_REMAPPING; + else if (packed_entry->operation == VDO_JOURNAL_BLOCK_MAP_INCREMENT) + entry->operation = VDO_JOURNAL_BLOCK_MAP_REMAPPING; + else + return false; + + low32 = __le32_to_cpu(packed_entry->pbn_low_word); + high4 = packed_entry->pbn_high_nibble; + entry->slot = (struct block_map_slot) { + .pbn = ((high4 << 32) | low32), + .slot = (packed_entry->slot_low | (packed_entry->slot_high << 6)), + }; + entry->mapping = vdo_unpack_block_map_entry(&packed_entry->block_map_entry); + entry->unmapping = (struct data_location) { + .pbn = VDO_ZERO_BLOCK, + .state = VDO_MAPPING_STATE_UNMAPPED, + }; + } + + return (validate_recovery_journal_entry(vdo, entry) == VDO_SUCCESS); +} + +/** + * append_sector_entries() - Append an array of recovery journal entries from a journal block + * sector to the array of numbered mappings in the repair completion, + * numbering each entry in the order they are appended. + * @repair: The repair completion. + * @entries: The entries in the sector. + * @format: The format of the sector. + * @entry_count: The number of entries to append. + */ +static void append_sector_entries(struct repair_completion *repair, char *entries, + enum vdo_metadata_type format, + journal_entry_count_t entry_count) +{ + journal_entry_count_t i; + struct vdo *vdo = repair->completion.vdo; + off_t increment = ((format == VDO_METADATA_RECOVERY_JOURNAL_2) + ? sizeof(struct packed_recovery_journal_entry) + : sizeof(struct packed_recovery_journal_entry_1)); + + for (i = 0; i < entry_count; i++, entries += increment) { + struct recovery_journal_entry entry; + + if (!unpack_entry(vdo, entries, format, &entry)) + /* When recovering from read-only mode, ignore damaged entries. */ + continue; + + repair->entries[repair->block_map_entry_count] = + (struct numbered_block_mapping) { + .block_map_slot = entry.slot, + .block_map_entry = vdo_pack_block_map_entry(entry.mapping.pbn, + entry.mapping.state), + .number = repair->block_map_entry_count, + }; + repair->block_map_entry_count++; + } +} + +static journal_entry_count_t entries_per_sector(enum vdo_metadata_type format, + u8 sector_number) +{ + if (format == VDO_METADATA_RECOVERY_JOURNAL_2) + return RECOVERY_JOURNAL_ENTRIES_PER_SECTOR; + + return ((sector_number == (VDO_SECTORS_PER_BLOCK - 1)) + ? RECOVERY_JOURNAL_1_ENTRIES_IN_LAST_SECTOR + : RECOVERY_JOURNAL_1_ENTRIES_PER_SECTOR); +} + +static void extract_entries_from_block(struct repair_completion *repair, + struct recovery_journal *journal, + sequence_number_t sequence, + enum vdo_metadata_type format, + journal_entry_count_t entries) +{ + sector_count_t i; + struct recovery_block_header header = + get_recovery_journal_block_header(journal, repair->journal_data, + sequence); + + if (!is_exact_recovery_journal_block(journal, &header, sequence, format)) { + /* This block is invalid, so skip it. */ + return; + } + + entries = min(entries, header.entry_count); + for (i = 1; i < VDO_SECTORS_PER_BLOCK; i++) { + struct packed_journal_sector *sector = + get_sector(journal, repair->journal_data, sequence, i); + journal_entry_count_t sector_entries = + min(entries, entries_per_sector(format, i)); + + if (vdo_is_valid_recovery_journal_sector(&header, sector, i)) { + /* Only extract as many as the block header calls for. */ + append_sector_entries(repair, (char *) sector->entries, format, + min_t(journal_entry_count_t, + sector->entry_count, + sector_entries)); + } + + /* + * Even if the sector wasn't full, count it as full when counting up to the + * entry count the block header claims. + */ + entries -= sector_entries; + } +} + +static int parse_journal_for_rebuild(struct repair_completion *repair) +{ + int result; + sequence_number_t i; + block_count_t count; + enum vdo_metadata_type format; + struct vdo *vdo = repair->completion.vdo; + struct recovery_journal *journal = vdo->recovery_journal; + journal_entry_count_t entries_per_block = journal->entries_per_block; + + format = get_recovery_journal_block_header(journal, repair->journal_data, + repair->highest_tail).metadata_type; + if (format == VDO_METADATA_RECOVERY_JOURNAL) + entries_per_block = RECOVERY_JOURNAL_1_ENTRIES_PER_BLOCK; + + /* + * Allocate an array of numbered_block_mapping structures large enough to transcribe every + * packed_recovery_journal_entry from every valid journal block. + */ + count = ((repair->highest_tail - repair->block_map_head + 1) * entries_per_block); + result = vdo_allocate(count, struct numbered_block_mapping, __func__, + &repair->entries); + if (result != VDO_SUCCESS) + return result; + + for (i = repair->block_map_head; i <= repair->highest_tail; i++) + extract_entries_from_block(repair, journal, i, format, entries_per_block); + + return VDO_SUCCESS; +} + +static int validate_heads(struct repair_completion *repair) +{ + /* Both reap heads must be behind the tail. */ + if ((repair->block_map_head <= repair->tail) && + (repair->slab_journal_head <= repair->tail)) + return VDO_SUCCESS; + + + return vdo_log_error_strerror(VDO_CORRUPT_JOURNAL, + "Journal tail too early. block map head: %llu, slab journal head: %llu, tail: %llu", + (unsigned long long) repair->block_map_head, + (unsigned long long) repair->slab_journal_head, + (unsigned long long) repair->tail); +} + +/** + * extract_new_mappings() - Find all valid new mappings to be applied to the block map. + * + * The mappings are extracted from the journal and stored in a sortable array so that all of the + * mappings to be applied to a given block map page can be done in a single page fetch. + */ +static int extract_new_mappings(struct repair_completion *repair) +{ + int result; + struct vdo *vdo = repair->completion.vdo; + struct recovery_point recovery_point = { + .sequence_number = repair->block_map_head, + .sector_count = 1, + .entry_count = 0, + }; + + /* + * Allocate an array of numbered_block_mapping structs just large enough to transcribe + * every packed_recovery_journal_entry from every valid journal block. + */ + result = vdo_allocate(repair->entry_count, struct numbered_block_mapping, + __func__, &repair->entries); + if (result != VDO_SUCCESS) + return result; + + for (; before_recovery_point(&recovery_point, &repair->tail_recovery_point); + increment_recovery_point(&recovery_point)) { + struct recovery_journal_entry entry = get_entry(repair, &recovery_point); + + result = validate_recovery_journal_entry(vdo, &entry); + if (result != VDO_SUCCESS) { + vdo_enter_read_only_mode(vdo, result); + return result; + } + + repair->entries[repair->block_map_entry_count] = + (struct numbered_block_mapping) { + .block_map_slot = entry.slot, + .block_map_entry = vdo_pack_block_map_entry(entry.mapping.pbn, + entry.mapping.state), + .number = repair->block_map_entry_count, + }; + repair->block_map_entry_count++; + } + + result = VDO_ASSERT((repair->block_map_entry_count <= repair->entry_count), + "approximate entry count is an upper bound"); + if (result != VDO_SUCCESS) + vdo_enter_read_only_mode(vdo, result); + + return result; +} + +/** + * compute_usages() - Compute the lbns in use and block map data blocks counts from the tail of + * the journal. + */ +static noinline int compute_usages(struct repair_completion *repair) +{ + /* + * This function is declared noinline to avoid a spurious valgrind error regarding the + * following structure being uninitialized. + */ + struct recovery_point recovery_point = { + .sequence_number = repair->tail, + .sector_count = 1, + .entry_count = 0, + }; + + struct vdo *vdo = repair->completion.vdo; + struct recovery_journal *journal = vdo->recovery_journal; + struct recovery_block_header header = + get_recovery_journal_block_header(journal, repair->journal_data, + repair->tail); + + repair->logical_blocks_used = header.logical_blocks_used; + repair->block_map_data_blocks = header.block_map_data_blocks; + + for (; before_recovery_point(&recovery_point, &repair->tail_recovery_point); + increment_recovery_point(&recovery_point)) { + struct recovery_journal_entry entry = get_entry(repair, &recovery_point); + int result; + + result = validate_recovery_journal_entry(vdo, &entry); + if (result != VDO_SUCCESS) { + vdo_enter_read_only_mode(vdo, result); + return result; + } + + if (entry.operation == VDO_JOURNAL_BLOCK_MAP_REMAPPING) { + repair->block_map_data_blocks++; + continue; + } + + if (vdo_is_mapped_location(&entry.mapping)) + repair->logical_blocks_used++; + + if (vdo_is_mapped_location(&entry.unmapping)) + repair->logical_blocks_used--; + } + + return VDO_SUCCESS; +} + +static int parse_journal_for_recovery(struct repair_completion *repair) +{ + int result; + sequence_number_t i, head; + bool found_entries = false; + struct recovery_journal *journal = repair->completion.vdo->recovery_journal; + + head = min(repair->block_map_head, repair->slab_journal_head); + for (i = head; i <= repair->highest_tail; i++) { + struct recovery_block_header header; + journal_entry_count_t block_entries; + u8 j; + + repair->tail = i; + repair->tail_recovery_point = (struct recovery_point) { + .sequence_number = i, + .sector_count = 0, + .entry_count = 0, + }; + + header = get_recovery_journal_block_header(journal, repair->journal_data, i); + if (header.metadata_type == VDO_METADATA_RECOVERY_JOURNAL) { + /* This is an old format block, so we need to upgrade */ + vdo_log_error_strerror(VDO_UNSUPPORTED_VERSION, + "Recovery journal is in the old format, a read-only rebuild is required."); + vdo_enter_read_only_mode(repair->completion.vdo, + VDO_UNSUPPORTED_VERSION); + return VDO_UNSUPPORTED_VERSION; + } + + if (!is_exact_recovery_journal_block(journal, &header, i, + VDO_METADATA_RECOVERY_JOURNAL_2)) { + /* A bad block header was found so this must be the end of the journal. */ + break; + } + + block_entries = header.entry_count; + + /* Examine each sector in turn to determine the last valid sector. */ + for (j = 1; j < VDO_SECTORS_PER_BLOCK; j++) { + struct packed_journal_sector *sector = + get_sector(journal, repair->journal_data, i, j); + journal_entry_count_t sector_entries = + min_t(journal_entry_count_t, sector->entry_count, + block_entries); + + /* A bad sector means that this block was torn. */ + if (!vdo_is_valid_recovery_journal_sector(&header, sector, j)) + break; + + if (sector_entries > 0) { + found_entries = true; + repair->tail_recovery_point.sector_count++; + repair->tail_recovery_point.entry_count = sector_entries; + block_entries -= sector_entries; + repair->entry_count += sector_entries; + } + + /* If this sector is short, the later sectors can't matter. */ + if ((sector_entries < RECOVERY_JOURNAL_ENTRIES_PER_SECTOR) || + (block_entries == 0)) + break; + } + + /* If this block was not filled, or if it tore, no later block can matter. */ + if ((header.entry_count != journal->entries_per_block) || (block_entries > 0)) + break; + } + + if (!found_entries) + return validate_heads(repair); + + /* Set the tail to the last valid tail block, if there is one. */ + if (repair->tail_recovery_point.sector_count == 0) + repair->tail--; + + result = validate_heads(repair); + if (result != VDO_SUCCESS) + return result; + + vdo_log_info("Highest-numbered recovery journal block has sequence number %llu, and the highest-numbered usable block is %llu", + (unsigned long long) repair->highest_tail, + (unsigned long long) repair->tail); + + result = extract_new_mappings(repair); + if (result != VDO_SUCCESS) + return result; + + return compute_usages(repair); +} + +static int parse_journal(struct repair_completion *repair) +{ + if (!find_recovery_journal_head_and_tail(repair)) + return VDO_SUCCESS; + + return (vdo_state_requires_read_only_rebuild(repair->completion.vdo->load_state) ? + parse_journal_for_rebuild(repair) : + parse_journal_for_recovery(repair)); +} + +static void finish_journal_load(struct vdo_completion *completion) +{ + struct repair_completion *repair = completion->parent; + + if (++repair->vios_complete != repair->vio_count) + return; + + vdo_log_info("Finished reading recovery journal"); + uninitialize_vios(repair); + prepare_repair_completion(repair, recover_block_map, VDO_ZONE_TYPE_LOGICAL); + vdo_continue_completion(&repair->completion, parse_journal(repair)); +} + +static void handle_journal_load_error(struct vdo_completion *completion) +{ + struct repair_completion *repair = completion->parent; + + /* Preserve the error */ + vdo_set_completion_result(&repair->completion, completion->result); + vio_record_metadata_io_error(as_vio(completion)); + completion->callback(completion); +} + +static void read_journal_endio(struct bio *bio) +{ + struct vio *vio = bio->bi_private; + struct vdo *vdo = vio->completion.vdo; + + continue_vio_after_io(vio, finish_journal_load, vdo->thread_config.admin_thread); +} + +/** + * vdo_repair() - Load the recovery journal and then recover or rebuild a vdo. + * @parent: The completion to notify when the operation is complete + */ +void vdo_repair(struct vdo_completion *parent) +{ + int result; + char *ptr; + struct repair_completion *repair; + struct vdo *vdo = parent->vdo; + struct recovery_journal *journal = vdo->recovery_journal; + physical_block_number_t pbn = journal->origin; + block_count_t remaining = journal->size; + block_count_t vio_count = DIV_ROUND_UP(remaining, MAX_BLOCKS_PER_VIO); + page_count_t page_count = min_t(page_count_t, + vdo->device_config->cache_size >> 1, + MAXIMUM_SIMULTANEOUS_VDO_BLOCK_MAP_RESTORATION_READS); + + vdo_assert_on_admin_thread(vdo, __func__); + + if (vdo->load_state == VDO_FORCE_REBUILD) { + vdo_log_warning("Rebuilding reference counts to clear read-only mode"); + vdo->states.vdo.read_only_recoveries++; + } else if (vdo->load_state == VDO_REBUILD_FOR_UPGRADE) { + vdo_log_warning("Rebuilding reference counts for upgrade"); + } else { + vdo_log_warning("Device was dirty, rebuilding reference counts"); + } + + result = vdo_allocate_extended(struct repair_completion, page_count, + struct vdo_page_completion, __func__, + &repair); + if (result != VDO_SUCCESS) { + vdo_fail_completion(parent, result); + return; + } + + vdo_initialize_completion(&repair->completion, vdo, VDO_REPAIR_COMPLETION); + repair->completion.error_handler = abort_repair; + repair->completion.parent = parent; + prepare_repair_completion(repair, finish_repair, VDO_ZONE_TYPE_ADMIN); + repair->page_count = page_count; + + result = vdo_allocate(remaining * VDO_BLOCK_SIZE, char, __func__, + &repair->journal_data); + if (abort_on_error(result, repair)) + return; + + result = vdo_allocate(vio_count, struct vio, __func__, &repair->vios); + if (abort_on_error(result, repair)) + return; + + ptr = repair->journal_data; + for (repair->vio_count = 0; repair->vio_count < vio_count; repair->vio_count++) { + block_count_t blocks = min_t(block_count_t, remaining, + MAX_BLOCKS_PER_VIO); + + result = allocate_vio_components(vdo, VIO_TYPE_RECOVERY_JOURNAL, + VIO_PRIORITY_METADATA, + repair, blocks, ptr, + &repair->vios[repair->vio_count]); + if (abort_on_error(result, repair)) + return; + + ptr += (blocks * VDO_BLOCK_SIZE); + remaining -= blocks; + } + + for (vio_count = 0; vio_count < repair->vio_count; + vio_count++, pbn += MAX_BLOCKS_PER_VIO) { + vdo_submit_metadata_vio(&repair->vios[vio_count], pbn, read_journal_endio, + handle_journal_load_error, REQ_OP_READ); + } +} |