diff options
Diffstat (limited to 'drivers/md/dm-vdo/indexer/volume-index.c')
| -rw-r--r-- | drivers/md/dm-vdo/indexer/volume-index.c | 1283 |
1 files changed, 1283 insertions, 0 deletions
diff --git a/drivers/md/dm-vdo/indexer/volume-index.c b/drivers/md/dm-vdo/indexer/volume-index.c new file mode 100644 index 0000000000..12f954a0c5 --- /dev/null +++ b/drivers/md/dm-vdo/indexer/volume-index.c @@ -0,0 +1,1283 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2023 Red Hat + */ +#include "volume-index.h" + +#include <linux/bitops.h> +#include <linux/bits.h> +#include <linux/cache.h> +#include <linux/compiler.h> +#include <linux/log2.h> + +#include "errors.h" +#include "logger.h" +#include "memory-alloc.h" +#include "numeric.h" +#include "permassert.h" +#include "thread-utils.h" + +#include "config.h" +#include "geometry.h" +#include "hash-utils.h" +#include "indexer.h" + +/* + * The volume index is a combination of two separate subindexes, one containing sparse hook entries + * (retained for all chapters), and one containing the remaining entries (retained only for the + * dense chapters). If there are no sparse chapters, only the non-hook sub index is used, and it + * will contain all records for all chapters. + * + * The volume index is also divided into zones, with one thread operating on each zone. Each + * incoming request is dispatched to the appropriate thread, and then to the appropriate subindex. + * Each delta list is handled by a single zone. To ensure that the distribution of delta lists to + * zones doesn't underflow (leaving some zone with no delta lists), the minimum number of delta + * lists must be the square of the maximum zone count for both subindexes. + * + * Each subindex zone is a delta index where the payload is a chapter number. The volume index can + * compute the delta list number, address, and zone number from the record name in order to + * dispatch record handling to the correct structures. + * + * Most operations that use all the zones take place either before request processing is allowed, + * or after all requests have been flushed in order to shut down. The only multi-threaded operation + * supported during normal operation is the uds_lookup_volume_index_name() method, used to determine + * whether a new chapter should be loaded into the sparse index cache. This operation only uses the + * sparse hook subindex, and the zone mutexes are used to make this operation safe. + * + * There are three ways of expressing chapter numbers in the volume index: virtual, index, and + * rolling. The interface to the volume index uses virtual chapter numbers, which are 64 bits long. + * Internally the subindex stores only the minimal number of bits necessary by masking away the + * high-order bits. When the index needs to deal with ordering of index chapter numbers, as when + * flushing entries from older chapters, it rolls the index chapter number around so that the + * smallest one in use is mapped to 0. See convert_index_to_virtual() or flush_invalid_entries() + * for an example of this technique. + * + * For efficiency, when older chapter numbers become invalid, the index does not immediately remove + * the invalidated entries. Instead it lazily removes them from a given delta list the next time it + * walks that list during normal operation. Because of this, the index size must be increased + * somewhat to accommodate all the invalid entries that have not yet been removed. For the standard + * index sizes, this requires about 4 chapters of old entries per 1024 chapters of valid entries in + * the index. + */ + +struct sub_index_parameters { + /* The number of bits in address mask */ + u8 address_bits; + /* The number of bits in chapter number */ + u8 chapter_bits; + /* The mean delta */ + u32 mean_delta; + /* The number of delta lists */ + u64 list_count; + /* The number of chapters used */ + u32 chapter_count; + /* The number of bits per chapter */ + size_t chapter_size_in_bits; + /* The number of bytes of delta list memory */ + size_t memory_size; + /* The number of bytes the index should keep free at all times */ + size_t target_free_bytes; +}; + +struct split_config { + /* The hook subindex configuration */ + struct uds_configuration hook_config; + struct index_geometry hook_geometry; + + /* The non-hook subindex configuration */ + struct uds_configuration non_hook_config; + struct index_geometry non_hook_geometry; +}; + +struct chapter_range { + u32 chapter_start; + u32 chapter_count; +}; + +#define MAGIC_SIZE 8 + +static const char MAGIC_START_5[] = "MI5-0005"; + +struct sub_index_data { + char magic[MAGIC_SIZE]; /* MAGIC_START_5 */ + u64 volume_nonce; + u64 virtual_chapter_low; + u64 virtual_chapter_high; + u32 first_list; + u32 list_count; +}; + +static const char MAGIC_START_6[] = "MI6-0001"; + +struct volume_index_data { + char magic[MAGIC_SIZE]; /* MAGIC_START_6 */ + u32 sparse_sample_rate; +}; + +static inline u32 extract_address(const struct volume_sub_index *sub_index, + const struct uds_record_name *name) +{ + return uds_extract_volume_index_bytes(name) & sub_index->address_mask; +} + +static inline u32 extract_dlist_num(const struct volume_sub_index *sub_index, + const struct uds_record_name *name) +{ + u64 bits = uds_extract_volume_index_bytes(name); + + return (bits >> sub_index->address_bits) % sub_index->list_count; +} + +static inline const struct volume_sub_index_zone * +get_zone_for_record(const struct volume_index_record *record) +{ + return &record->sub_index->zones[record->zone_number]; +} + +static inline u64 convert_index_to_virtual(const struct volume_index_record *record, + u32 index_chapter) +{ + const struct volume_sub_index_zone *volume_index_zone = get_zone_for_record(record); + u32 rolling_chapter = ((index_chapter - volume_index_zone->virtual_chapter_low) & + record->sub_index->chapter_mask); + + return volume_index_zone->virtual_chapter_low + rolling_chapter; +} + +static inline u32 convert_virtual_to_index(const struct volume_sub_index *sub_index, + u64 virtual_chapter) +{ + return virtual_chapter & sub_index->chapter_mask; +} + +static inline bool is_virtual_chapter_indexed(const struct volume_index_record *record, + u64 virtual_chapter) +{ + const struct volume_sub_index_zone *volume_index_zone = get_zone_for_record(record); + + return ((virtual_chapter >= volume_index_zone->virtual_chapter_low) && + (virtual_chapter <= volume_index_zone->virtual_chapter_high)); +} + +static inline bool has_sparse(const struct volume_index *volume_index) +{ + return volume_index->sparse_sample_rate > 0; +} + +bool uds_is_volume_index_sample(const struct volume_index *volume_index, + const struct uds_record_name *name) +{ + if (!has_sparse(volume_index)) + return false; + + return (uds_extract_sampling_bytes(name) % volume_index->sparse_sample_rate) == 0; +} + +static inline const struct volume_sub_index * +get_volume_sub_index(const struct volume_index *volume_index, + const struct uds_record_name *name) +{ + return (uds_is_volume_index_sample(volume_index, name) ? + &volume_index->vi_hook : + &volume_index->vi_non_hook); +} + +static unsigned int get_volume_sub_index_zone(const struct volume_sub_index *sub_index, + const struct uds_record_name *name) +{ + return extract_dlist_num(sub_index, name) / sub_index->delta_index.lists_per_zone; +} + +unsigned int uds_get_volume_index_zone(const struct volume_index *volume_index, + const struct uds_record_name *name) +{ + return get_volume_sub_index_zone(get_volume_sub_index(volume_index, name), name); +} + +#define DELTA_LIST_SIZE 256 + +static int compute_volume_sub_index_parameters(const struct uds_configuration *config, + struct sub_index_parameters *params) +{ + u64 entries_in_volume_index, address_span; + u32 chapters_in_volume_index, invalid_chapters; + u32 rounded_chapters; + u64 delta_list_records; + u32 address_count; + u64 index_size_in_bits; + size_t expected_index_size; + u64 min_delta_lists = MAX_ZONES * MAX_ZONES; + struct index_geometry *geometry = config->geometry; + u64 records_per_chapter = geometry->records_per_chapter; + + params->chapter_count = geometry->chapters_per_volume; + /* + * Make sure that the number of delta list records in the volume index does not change when + * the volume is reduced by one chapter. This preserves the mapping from name to volume + * index delta list. + */ + rounded_chapters = params->chapter_count; + if (uds_is_reduced_index_geometry(geometry)) + rounded_chapters += 1; + delta_list_records = records_per_chapter * rounded_chapters; + address_count = config->volume_index_mean_delta * DELTA_LIST_SIZE; + params->list_count = max(delta_list_records / DELTA_LIST_SIZE, min_delta_lists); + params->address_bits = bits_per(address_count - 1); + params->chapter_bits = bits_per(rounded_chapters - 1); + if ((u32) params->list_count != params->list_count) { + return vdo_log_warning_strerror(UDS_INVALID_ARGUMENT, + "cannot initialize volume index with %llu delta lists", + (unsigned long long) params->list_count); + } + + if (params->address_bits > 31) { + return vdo_log_warning_strerror(UDS_INVALID_ARGUMENT, + "cannot initialize volume index with %u address bits", + params->address_bits); + } + + /* + * The probability that a given delta list is not touched during the writing of an entire + * chapter is: + * + * double p_not_touched = pow((double) (params->list_count - 1) / params->list_count, + * records_per_chapter); + * + * For the standard index sizes, about 78% of the delta lists are not touched, and + * therefore contain old index entries that have not been eliminated by the lazy LRU + * processing. Then the number of old index entries that accumulate over the entire index, + * in terms of full chapters worth of entries, is: + * + * double invalid_chapters = p_not_touched / (1.0 - p_not_touched); + * + * For the standard index sizes, the index needs about 3.5 chapters of space for the old + * entries in a 1024 chapter index, so round this up to use 4 chapters per 1024 chapters in + * the index. + */ + invalid_chapters = max(rounded_chapters / 256, 2U); + chapters_in_volume_index = rounded_chapters + invalid_chapters; + entries_in_volume_index = records_per_chapter * chapters_in_volume_index; + + address_span = params->list_count << params->address_bits; + params->mean_delta = address_span / entries_in_volume_index; + + /* + * Compute the expected size of a full index, then set the total memory to be 6% larger + * than that expected size. This number should be large enough that there are not many + * rebalances when the index is full. + */ + params->chapter_size_in_bits = uds_compute_delta_index_size(records_per_chapter, + params->mean_delta, + params->chapter_bits); + index_size_in_bits = params->chapter_size_in_bits * chapters_in_volume_index; + expected_index_size = index_size_in_bits / BITS_PER_BYTE; + params->memory_size = expected_index_size * 106 / 100; + + params->target_free_bytes = expected_index_size / 20; + return UDS_SUCCESS; +} + +static void uninitialize_volume_sub_index(struct volume_sub_index *sub_index) +{ + vdo_free(vdo_forget(sub_index->flush_chapters)); + vdo_free(vdo_forget(sub_index->zones)); + uds_uninitialize_delta_index(&sub_index->delta_index); +} + +void uds_free_volume_index(struct volume_index *volume_index) +{ + if (volume_index == NULL) + return; + + if (volume_index->zones != NULL) + vdo_free(vdo_forget(volume_index->zones)); + + uninitialize_volume_sub_index(&volume_index->vi_non_hook); + uninitialize_volume_sub_index(&volume_index->vi_hook); + vdo_free(volume_index); +} + + +static int compute_volume_sub_index_save_bytes(const struct uds_configuration *config, + size_t *bytes) +{ + struct sub_index_parameters params = { .address_bits = 0 }; + int result; + + result = compute_volume_sub_index_parameters(config, ¶ms); + if (result != UDS_SUCCESS) + return result; + + *bytes = (sizeof(struct sub_index_data) + params.list_count * sizeof(u64) + + uds_compute_delta_index_save_bytes(params.list_count, + params.memory_size)); + return UDS_SUCCESS; +} + +/* This function is only useful if the configuration includes sparse chapters. */ +static void split_configuration(const struct uds_configuration *config, + struct split_config *split) +{ + u64 sample_rate, sample_records; + u64 dense_chapters, sparse_chapters; + + /* Start with copies of the base configuration. */ + split->hook_config = *config; + split->hook_geometry = *config->geometry; + split->hook_config.geometry = &split->hook_geometry; + split->non_hook_config = *config; + split->non_hook_geometry = *config->geometry; + split->non_hook_config.geometry = &split->non_hook_geometry; + + sample_rate = config->sparse_sample_rate; + sparse_chapters = config->geometry->sparse_chapters_per_volume; + dense_chapters = config->geometry->chapters_per_volume - sparse_chapters; + sample_records = config->geometry->records_per_chapter / sample_rate; + + /* Adjust the number of records indexed for each chapter. */ + split->hook_geometry.records_per_chapter = sample_records; + split->non_hook_geometry.records_per_chapter -= sample_records; + + /* Adjust the number of chapters indexed. */ + split->hook_geometry.sparse_chapters_per_volume = 0; + split->non_hook_geometry.sparse_chapters_per_volume = 0; + split->non_hook_geometry.chapters_per_volume = dense_chapters; +} + +static int compute_volume_index_save_bytes(const struct uds_configuration *config, + size_t *bytes) +{ + size_t hook_bytes, non_hook_bytes; + struct split_config split; + int result; + + if (!uds_is_sparse_index_geometry(config->geometry)) + return compute_volume_sub_index_save_bytes(config, bytes); + + split_configuration(config, &split); + result = compute_volume_sub_index_save_bytes(&split.hook_config, &hook_bytes); + if (result != UDS_SUCCESS) + return result; + + result = compute_volume_sub_index_save_bytes(&split.non_hook_config, + &non_hook_bytes); + if (result != UDS_SUCCESS) + return result; + + *bytes = sizeof(struct volume_index_data) + hook_bytes + non_hook_bytes; + return UDS_SUCCESS; +} + +int uds_compute_volume_index_save_blocks(const struct uds_configuration *config, + size_t block_size, u64 *block_count) +{ + size_t bytes; + int result; + + result = compute_volume_index_save_bytes(config, &bytes); + if (result != UDS_SUCCESS) + return result; + + bytes += sizeof(struct delta_list_save_info); + *block_count = DIV_ROUND_UP(bytes, block_size) + MAX_ZONES; + return UDS_SUCCESS; +} + +/* Flush invalid entries while walking the delta list. */ +static inline int flush_invalid_entries(struct volume_index_record *record, + struct chapter_range *flush_range, + u32 *next_chapter_to_invalidate) +{ + int result; + + result = uds_next_delta_index_entry(&record->delta_entry); + if (result != UDS_SUCCESS) + return result; + + while (!record->delta_entry.at_end) { + u32 index_chapter = uds_get_delta_entry_value(&record->delta_entry); + u32 relative_chapter = ((index_chapter - flush_range->chapter_start) & + record->sub_index->chapter_mask); + + if (likely(relative_chapter >= flush_range->chapter_count)) { + if (relative_chapter < *next_chapter_to_invalidate) + *next_chapter_to_invalidate = relative_chapter; + break; + } + + result = uds_remove_delta_index_entry(&record->delta_entry); + if (result != UDS_SUCCESS) + return result; + } + + return UDS_SUCCESS; +} + +/* Find the matching record, or the list offset where the record would go. */ +static int get_volume_index_entry(struct volume_index_record *record, u32 list_number, + u32 key, struct chapter_range *flush_range) +{ + struct volume_index_record other_record; + const struct volume_sub_index *sub_index = record->sub_index; + u32 next_chapter_to_invalidate = sub_index->chapter_mask; + int result; + + result = uds_start_delta_index_search(&sub_index->delta_index, list_number, 0, + &record->delta_entry); + if (result != UDS_SUCCESS) + return result; + + do { + result = flush_invalid_entries(record, flush_range, + &next_chapter_to_invalidate); + if (result != UDS_SUCCESS) + return result; + } while (!record->delta_entry.at_end && (key > record->delta_entry.key)); + + result = uds_remember_delta_index_offset(&record->delta_entry); + if (result != UDS_SUCCESS) + return result; + + /* Check any collision records for a more precise match. */ + other_record = *record; + if (!other_record.delta_entry.at_end && (key == other_record.delta_entry.key)) { + for (;;) { + u8 collision_name[UDS_RECORD_NAME_SIZE]; + + result = flush_invalid_entries(&other_record, flush_range, + &next_chapter_to_invalidate); + if (result != UDS_SUCCESS) + return result; + + if (other_record.delta_entry.at_end || + !other_record.delta_entry.is_collision) + break; + + result = uds_get_delta_entry_collision(&other_record.delta_entry, + collision_name); + if (result != UDS_SUCCESS) + return result; + + if (memcmp(collision_name, record->name, UDS_RECORD_NAME_SIZE) == 0) { + *record = other_record; + break; + } + } + } + while (!other_record.delta_entry.at_end) { + result = flush_invalid_entries(&other_record, flush_range, + &next_chapter_to_invalidate); + if (result != UDS_SUCCESS) + return result; + } + next_chapter_to_invalidate += flush_range->chapter_start; + next_chapter_to_invalidate &= sub_index->chapter_mask; + flush_range->chapter_start = next_chapter_to_invalidate; + flush_range->chapter_count = 0; + return UDS_SUCCESS; +} + +static int get_volume_sub_index_record(struct volume_sub_index *sub_index, + const struct uds_record_name *name, + struct volume_index_record *record) +{ + int result; + const struct volume_sub_index_zone *volume_index_zone; + u32 address = extract_address(sub_index, name); + u32 delta_list_number = extract_dlist_num(sub_index, name); + u64 flush_chapter = sub_index->flush_chapters[delta_list_number]; + + record->sub_index = sub_index; + record->mutex = NULL; + record->name = name; + record->zone_number = delta_list_number / sub_index->delta_index.lists_per_zone; + volume_index_zone = get_zone_for_record(record); + + if (flush_chapter < volume_index_zone->virtual_chapter_low) { + struct chapter_range range; + u64 flush_count = volume_index_zone->virtual_chapter_low - flush_chapter; + + range.chapter_start = convert_virtual_to_index(sub_index, flush_chapter); + range.chapter_count = (flush_count > sub_index->chapter_mask ? + sub_index->chapter_mask + 1 : + flush_count); + result = get_volume_index_entry(record, delta_list_number, address, + &range); + flush_chapter = convert_index_to_virtual(record, range.chapter_start); + if (flush_chapter > volume_index_zone->virtual_chapter_high) + flush_chapter = volume_index_zone->virtual_chapter_high; + sub_index->flush_chapters[delta_list_number] = flush_chapter; + } else { + result = uds_get_delta_index_entry(&sub_index->delta_index, + delta_list_number, address, + name->name, &record->delta_entry); + } + + if (result != UDS_SUCCESS) + return result; + + record->is_found = + (!record->delta_entry.at_end && (record->delta_entry.key == address)); + if (record->is_found) { + u32 index_chapter = uds_get_delta_entry_value(&record->delta_entry); + + record->virtual_chapter = convert_index_to_virtual(record, index_chapter); + } + + record->is_collision = record->delta_entry.is_collision; + return UDS_SUCCESS; +} + +int uds_get_volume_index_record(struct volume_index *volume_index, + const struct uds_record_name *name, + struct volume_index_record *record) +{ + int result; + + if (uds_is_volume_index_sample(volume_index, name)) { + /* + * Other threads cannot be allowed to call uds_lookup_volume_index_name() while + * this thread is finding the volume index record. Due to the lazy LRU flushing of + * the volume index, uds_get_volume_index_record() is not a read-only operation. + */ + unsigned int zone = + get_volume_sub_index_zone(&volume_index->vi_hook, name); + struct mutex *mutex = &volume_index->zones[zone].hook_mutex; + + mutex_lock(mutex); + result = get_volume_sub_index_record(&volume_index->vi_hook, name, + record); + mutex_unlock(mutex); + /* Remember the mutex so that other operations on the index record can use it. */ + record->mutex = mutex; + } else { + result = get_volume_sub_index_record(&volume_index->vi_non_hook, name, + record); + } + + return result; +} + +int uds_put_volume_index_record(struct volume_index_record *record, u64 virtual_chapter) +{ + int result; + u32 address; + const struct volume_sub_index *sub_index = record->sub_index; + + if (!is_virtual_chapter_indexed(record, virtual_chapter)) { + u64 low = get_zone_for_record(record)->virtual_chapter_low; + u64 high = get_zone_for_record(record)->virtual_chapter_high; + + return vdo_log_warning_strerror(UDS_INVALID_ARGUMENT, + "cannot put record into chapter number %llu that is out of the valid range %llu to %llu", + (unsigned long long) virtual_chapter, + (unsigned long long) low, + (unsigned long long) high); + } + address = extract_address(sub_index, record->name); + if (unlikely(record->mutex != NULL)) + mutex_lock(record->mutex); + result = uds_put_delta_index_entry(&record->delta_entry, address, + convert_virtual_to_index(sub_index, + virtual_chapter), + record->is_found ? record->name->name : NULL); + if (unlikely(record->mutex != NULL)) + mutex_unlock(record->mutex); + switch (result) { + case UDS_SUCCESS: + record->virtual_chapter = virtual_chapter; + record->is_collision = record->delta_entry.is_collision; + record->is_found = true; + break; + case UDS_OVERFLOW: + vdo_log_ratelimit(vdo_log_warning_strerror, UDS_OVERFLOW, + "Volume index entry dropped due to overflow condition"); + uds_log_delta_index_entry(&record->delta_entry); + break; + default: + break; + } + + return result; +} + +int uds_remove_volume_index_record(struct volume_index_record *record) +{ + int result; + + if (!record->is_found) + return vdo_log_warning_strerror(UDS_BAD_STATE, + "illegal operation on new record"); + + /* Mark the record so that it cannot be used again */ + record->is_found = false; + if (unlikely(record->mutex != NULL)) + mutex_lock(record->mutex); + result = uds_remove_delta_index_entry(&record->delta_entry); + if (unlikely(record->mutex != NULL)) + mutex_unlock(record->mutex); + return result; +} + +static void set_volume_sub_index_zone_open_chapter(struct volume_sub_index *sub_index, + unsigned int zone_number, + u64 virtual_chapter) +{ + u64 used_bits = 0; + struct volume_sub_index_zone *zone = &sub_index->zones[zone_number]; + struct delta_zone *delta_zone; + u32 i; + + zone->virtual_chapter_low = (virtual_chapter >= sub_index->chapter_count ? + virtual_chapter - sub_index->chapter_count + 1 : + 0); + zone->virtual_chapter_high = virtual_chapter; + + /* Check to see if the new zone data is too large. */ + delta_zone = &sub_index->delta_index.delta_zones[zone_number]; + for (i = 1; i <= delta_zone->list_count; i++) + used_bits += delta_zone->delta_lists[i].size; + + if (used_bits > sub_index->max_zone_bits) { + /* Expire enough chapters to free the desired space. */ + u64 expire_count = + 1 + (used_bits - sub_index->max_zone_bits) / sub_index->chapter_zone_bits; + + if (expire_count == 1) { + vdo_log_ratelimit(vdo_log_info, + "zone %u: At chapter %llu, expiring chapter %llu early", + zone_number, + (unsigned long long) virtual_chapter, + (unsigned long long) zone->virtual_chapter_low); + zone->early_flushes++; + zone->virtual_chapter_low++; + } else { + u64 first_expired = zone->virtual_chapter_low; + + if (first_expired + expire_count < zone->virtual_chapter_high) { + zone->early_flushes += expire_count; + zone->virtual_chapter_low += expire_count; + } else { + zone->early_flushes += + zone->virtual_chapter_high - zone->virtual_chapter_low; + zone->virtual_chapter_low = zone->virtual_chapter_high; + } + vdo_log_ratelimit(vdo_log_info, + "zone %u: At chapter %llu, expiring chapters %llu to %llu early", + zone_number, + (unsigned long long) virtual_chapter, + (unsigned long long) first_expired, + (unsigned long long) zone->virtual_chapter_low - 1); + } + } +} + +void uds_set_volume_index_zone_open_chapter(struct volume_index *volume_index, + unsigned int zone_number, + u64 virtual_chapter) +{ + struct mutex *mutex = &volume_index->zones[zone_number].hook_mutex; + + set_volume_sub_index_zone_open_chapter(&volume_index->vi_non_hook, zone_number, + virtual_chapter); + + /* + * Other threads cannot be allowed to call uds_lookup_volume_index_name() while the open + * chapter number is changing. + */ + if (has_sparse(volume_index)) { + mutex_lock(mutex); + set_volume_sub_index_zone_open_chapter(&volume_index->vi_hook, + zone_number, virtual_chapter); + mutex_unlock(mutex); + } +} + +/* + * Set the newest open chapter number for the index, while also advancing the oldest valid chapter + * number. + */ +void uds_set_volume_index_open_chapter(struct volume_index *volume_index, + u64 virtual_chapter) +{ + unsigned int zone; + + for (zone = 0; zone < volume_index->zone_count; zone++) + uds_set_volume_index_zone_open_chapter(volume_index, zone, virtual_chapter); +} + +int uds_set_volume_index_record_chapter(struct volume_index_record *record, + u64 virtual_chapter) +{ + const struct volume_sub_index *sub_index = record->sub_index; + int result; + + if (!record->is_found) + return vdo_log_warning_strerror(UDS_BAD_STATE, + "illegal operation on new record"); + + if (!is_virtual_chapter_indexed(record, virtual_chapter)) { + u64 low = get_zone_for_record(record)->virtual_chapter_low; + u64 high = get_zone_for_record(record)->virtual_chapter_high; + + return vdo_log_warning_strerror(UDS_INVALID_ARGUMENT, + "cannot set chapter number %llu that is out of the valid range %llu to %llu", + (unsigned long long) virtual_chapter, + (unsigned long long) low, + (unsigned long long) high); + } + + if (unlikely(record->mutex != NULL)) + mutex_lock(record->mutex); + result = uds_set_delta_entry_value(&record->delta_entry, + convert_virtual_to_index(sub_index, + virtual_chapter)); + if (unlikely(record->mutex != NULL)) + mutex_unlock(record->mutex); + if (result != UDS_SUCCESS) + return result; + + record->virtual_chapter = virtual_chapter; + return UDS_SUCCESS; +} + +static u64 lookup_volume_sub_index_name(const struct volume_sub_index *sub_index, + const struct uds_record_name *name) +{ + int result; + u32 address = extract_address(sub_index, name); + u32 delta_list_number = extract_dlist_num(sub_index, name); + unsigned int zone_number = get_volume_sub_index_zone(sub_index, name); + const struct volume_sub_index_zone *zone = &sub_index->zones[zone_number]; + u64 virtual_chapter; + u32 index_chapter; + u32 rolling_chapter; + struct delta_index_entry delta_entry; + + result = uds_get_delta_index_entry(&sub_index->delta_index, delta_list_number, + address, name->name, &delta_entry); + if (result != UDS_SUCCESS) + return NO_CHAPTER; + + if (delta_entry.at_end || (delta_entry.key != address)) + return NO_CHAPTER; + + index_chapter = uds_get_delta_entry_value(&delta_entry); + rolling_chapter = (index_chapter - zone->virtual_chapter_low) & sub_index->chapter_mask; + + virtual_chapter = zone->virtual_chapter_low + rolling_chapter; + if (virtual_chapter > zone->virtual_chapter_high) + return NO_CHAPTER; + + return virtual_chapter; +} + +/* Do a read-only lookup of the record name for sparse cache management. */ +u64 uds_lookup_volume_index_name(const struct volume_index *volume_index, + const struct uds_record_name *name) +{ + unsigned int zone_number = uds_get_volume_index_zone(volume_index, name); + struct mutex *mutex = &volume_index->zones[zone_number].hook_mutex; + u64 virtual_chapter; + + if (!uds_is_volume_index_sample(volume_index, name)) + return NO_CHAPTER; + + mutex_lock(mutex); + virtual_chapter = lookup_volume_sub_index_name(&volume_index->vi_hook, name); + mutex_unlock(mutex); + + return virtual_chapter; +} + +static void abort_restoring_volume_sub_index(struct volume_sub_index *sub_index) +{ + uds_reset_delta_index(&sub_index->delta_index); +} + +static void abort_restoring_volume_index(struct volume_index *volume_index) +{ + abort_restoring_volume_sub_index(&volume_index->vi_non_hook); + if (has_sparse(volume_index)) + abort_restoring_volume_sub_index(&volume_index->vi_hook); +} + +static int start_restoring_volume_sub_index(struct volume_sub_index *sub_index, + struct buffered_reader **readers, + unsigned int reader_count) +{ + unsigned int z; + int result; + u64 virtual_chapter_low = 0, virtual_chapter_high = 0; + unsigned int i; + + for (i = 0; i < reader_count; i++) { + struct sub_index_data header; + u8 buffer[sizeof(struct sub_index_data)]; + size_t offset = 0; + u32 j; + + result = uds_read_from_buffered_reader(readers[i], buffer, + sizeof(buffer)); + if (result != UDS_SUCCESS) { + return vdo_log_warning_strerror(result, + "failed to read volume index header"); + } + + memcpy(&header.magic, buffer, MAGIC_SIZE); + offset += MAGIC_SIZE; + decode_u64_le(buffer, &offset, &header.volume_nonce); + decode_u64_le(buffer, &offset, &header.virtual_chapter_low); + decode_u64_le(buffer, &offset, &header.virtual_chapter_high); + decode_u32_le(buffer, &offset, &header.first_list); + decode_u32_le(buffer, &offset, &header.list_count); + + result = VDO_ASSERT(offset == sizeof(buffer), + "%zu bytes decoded of %zu expected", offset, + sizeof(buffer)); + if (result != VDO_SUCCESS) + result = UDS_CORRUPT_DATA; + + if (memcmp(header.magic, MAGIC_START_5, MAGIC_SIZE) != 0) { + return vdo_log_warning_strerror(UDS_CORRUPT_DATA, + "volume index file had bad magic number"); + } + + if (sub_index->volume_nonce == 0) { + sub_index->volume_nonce = header.volume_nonce; + } else if (header.volume_nonce != sub_index->volume_nonce) { + return vdo_log_warning_strerror(UDS_CORRUPT_DATA, + "volume index volume nonce incorrect"); + } + + if (i == 0) { + virtual_chapter_low = header.virtual_chapter_low; + virtual_chapter_high = header.virtual_chapter_high; + } else if (virtual_chapter_high != header.virtual_chapter_high) { + u64 low = header.virtual_chapter_low; + u64 high = header.virtual_chapter_high; + + return vdo_log_warning_strerror(UDS_CORRUPT_DATA, + "Inconsistent volume index zone files: Chapter range is [%llu,%llu], chapter range %d is [%llu,%llu]", + (unsigned long long) virtual_chapter_low, + (unsigned long long) virtual_chapter_high, + i, (unsigned long long) low, + (unsigned long long) high); + } else if (virtual_chapter_low < header.virtual_chapter_low) { + virtual_chapter_low = header.virtual_chapter_low; + } + + for (j = 0; j < header.list_count; j++) { + u8 decoded[sizeof(u64)]; + + result = uds_read_from_buffered_reader(readers[i], decoded, + sizeof(u64)); + if (result != UDS_SUCCESS) { + return vdo_log_warning_strerror(result, + "failed to read volume index flush ranges"); + } + + sub_index->flush_chapters[header.first_list + j] = + get_unaligned_le64(decoded); + } + } + + for (z = 0; z < sub_index->zone_count; z++) { + memset(&sub_index->zones[z], 0, sizeof(struct volume_sub_index_zone)); + sub_index->zones[z].virtual_chapter_low = virtual_chapter_low; + sub_index->zones[z].virtual_chapter_high = virtual_chapter_high; + } + + result = uds_start_restoring_delta_index(&sub_index->delta_index, readers, + reader_count); + if (result != UDS_SUCCESS) + return vdo_log_warning_strerror(result, "restoring delta index failed"); + + return UDS_SUCCESS; +} + +static int start_restoring_volume_index(struct volume_index *volume_index, + struct buffered_reader **buffered_readers, + unsigned int reader_count) +{ + unsigned int i; + int result; + + if (!has_sparse(volume_index)) { + return start_restoring_volume_sub_index(&volume_index->vi_non_hook, + buffered_readers, reader_count); + } + + for (i = 0; i < reader_count; i++) { + struct volume_index_data header; + u8 buffer[sizeof(struct volume_index_data)]; + size_t offset = 0; + + result = uds_read_from_buffered_reader(buffered_readers[i], buffer, + sizeof(buffer)); + if (result != UDS_SUCCESS) { + return vdo_log_warning_strerror(result, + "failed to read volume index header"); + } + + memcpy(&header.magic, buffer, MAGIC_SIZE); + offset += MAGIC_SIZE; + decode_u32_le(buffer, &offset, &header.sparse_sample_rate); + + result = VDO_ASSERT(offset == sizeof(buffer), + "%zu bytes decoded of %zu expected", offset, + sizeof(buffer)); + if (result != VDO_SUCCESS) + result = UDS_CORRUPT_DATA; + + if (memcmp(header.magic, MAGIC_START_6, MAGIC_SIZE) != 0) + return vdo_log_warning_strerror(UDS_CORRUPT_DATA, + "volume index file had bad magic number"); + + if (i == 0) { + volume_index->sparse_sample_rate = header.sparse_sample_rate; + } else if (volume_index->sparse_sample_rate != header.sparse_sample_rate) { + vdo_log_warning_strerror(UDS_CORRUPT_DATA, + "Inconsistent sparse sample rate in delta index zone files: %u vs. %u", + volume_index->sparse_sample_rate, + header.sparse_sample_rate); + return UDS_CORRUPT_DATA; + } + } + + result = start_restoring_volume_sub_index(&volume_index->vi_non_hook, + buffered_readers, reader_count); + if (result != UDS_SUCCESS) + return result; + + return start_restoring_volume_sub_index(&volume_index->vi_hook, buffered_readers, + reader_count); +} + +static int finish_restoring_volume_sub_index(struct volume_sub_index *sub_index, + struct buffered_reader **buffered_readers, + unsigned int reader_count) +{ + return uds_finish_restoring_delta_index(&sub_index->delta_index, + buffered_readers, reader_count); +} + +static int finish_restoring_volume_index(struct volume_index *volume_index, + struct buffered_reader **buffered_readers, + unsigned int reader_count) +{ + int result; + + result = finish_restoring_volume_sub_index(&volume_index->vi_non_hook, + buffered_readers, reader_count); + if ((result == UDS_SUCCESS) && has_sparse(volume_index)) { + result = finish_restoring_volume_sub_index(&volume_index->vi_hook, + buffered_readers, + reader_count); + } + + return result; +} + +int uds_load_volume_index(struct volume_index *volume_index, + struct buffered_reader **readers, unsigned int reader_count) +{ + int result; + + /* Start by reading the header section of the stream. */ + result = start_restoring_volume_index(volume_index, readers, reader_count); + if (result != UDS_SUCCESS) + return result; + + result = finish_restoring_volume_index(volume_index, readers, reader_count); + if (result != UDS_SUCCESS) { + abort_restoring_volume_index(volume_index); + return result; + } + + /* Check the final guard lists to make sure there is no extra data. */ + result = uds_check_guard_delta_lists(readers, reader_count); + if (result != UDS_SUCCESS) + abort_restoring_volume_index(volume_index); + + return result; +} + +static int start_saving_volume_sub_index(const struct volume_sub_index *sub_index, + unsigned int zone_number, + struct buffered_writer *buffered_writer) +{ + int result; + struct volume_sub_index_zone *volume_index_zone = &sub_index->zones[zone_number]; + u32 first_list = sub_index->delta_index.delta_zones[zone_number].first_list; + u32 list_count = sub_index->delta_index.delta_zones[zone_number].list_count; + u8 buffer[sizeof(struct sub_index_data)]; + size_t offset = 0; + u32 i; + + memcpy(buffer, MAGIC_START_5, MAGIC_SIZE); + offset += MAGIC_SIZE; + encode_u64_le(buffer, &offset, sub_index->volume_nonce); + encode_u64_le(buffer, &offset, volume_index_zone->virtual_chapter_low); + encode_u64_le(buffer, &offset, volume_index_zone->virtual_chapter_high); + encode_u32_le(buffer, &offset, first_list); + encode_u32_le(buffer, &offset, list_count); + + result = VDO_ASSERT(offset == sizeof(struct sub_index_data), + "%zu bytes of config written, of %zu expected", offset, + sizeof(struct sub_index_data)); + if (result != VDO_SUCCESS) + return result; + + result = uds_write_to_buffered_writer(buffered_writer, buffer, offset); + if (result != UDS_SUCCESS) + return vdo_log_warning_strerror(result, + "failed to write volume index header"); + + for (i = 0; i < list_count; i++) { + u8 encoded[sizeof(u64)]; + + put_unaligned_le64(sub_index->flush_chapters[first_list + i], &encoded); + result = uds_write_to_buffered_writer(buffered_writer, encoded, + sizeof(u64)); + if (result != UDS_SUCCESS) { + return vdo_log_warning_strerror(result, + "failed to write volume index flush ranges"); + } + } + + return uds_start_saving_delta_index(&sub_index->delta_index, zone_number, + buffered_writer); +} + +static int start_saving_volume_index(const struct volume_index *volume_index, + unsigned int zone_number, + struct buffered_writer *writer) +{ + u8 buffer[sizeof(struct volume_index_data)]; + size_t offset = 0; + int result; + + if (!has_sparse(volume_index)) { + return start_saving_volume_sub_index(&volume_index->vi_non_hook, + zone_number, writer); + } + + memcpy(buffer, MAGIC_START_6, MAGIC_SIZE); + offset += MAGIC_SIZE; + encode_u32_le(buffer, &offset, volume_index->sparse_sample_rate); + result = VDO_ASSERT(offset == sizeof(struct volume_index_data), + "%zu bytes of header written, of %zu expected", offset, + sizeof(struct volume_index_data)); + if (result != VDO_SUCCESS) + return result; + + result = uds_write_to_buffered_writer(writer, buffer, offset); + if (result != UDS_SUCCESS) { + vdo_log_warning_strerror(result, "failed to write volume index header"); + return result; + } + + result = start_saving_volume_sub_index(&volume_index->vi_non_hook, zone_number, + writer); + if (result != UDS_SUCCESS) + return result; + + return start_saving_volume_sub_index(&volume_index->vi_hook, zone_number, + writer); +} + +static int finish_saving_volume_sub_index(const struct volume_sub_index *sub_index, + unsigned int zone_number) +{ + return uds_finish_saving_delta_index(&sub_index->delta_index, zone_number); +} + +static int finish_saving_volume_index(const struct volume_index *volume_index, + unsigned int zone_number) +{ + int result; + + result = finish_saving_volume_sub_index(&volume_index->vi_non_hook, zone_number); + if ((result == UDS_SUCCESS) && has_sparse(volume_index)) + result = finish_saving_volume_sub_index(&volume_index->vi_hook, zone_number); + return result; +} + +int uds_save_volume_index(struct volume_index *volume_index, + struct buffered_writer **writers, unsigned int writer_count) +{ + int result = UDS_SUCCESS; + unsigned int zone; + + for (zone = 0; zone < writer_count; zone++) { + result = start_saving_volume_index(volume_index, zone, writers[zone]); + if (result != UDS_SUCCESS) + break; + + result = finish_saving_volume_index(volume_index, zone); + if (result != UDS_SUCCESS) + break; + + result = uds_write_guard_delta_list(writers[zone]); + if (result != UDS_SUCCESS) + break; + + result = uds_flush_buffered_writer(writers[zone]); + if (result != UDS_SUCCESS) + break; + } + + return result; +} + +static void get_volume_sub_index_stats(const struct volume_sub_index *sub_index, + struct volume_index_stats *stats) +{ + struct delta_index_stats dis; + unsigned int z; + + uds_get_delta_index_stats(&sub_index->delta_index, &dis); + stats->rebalance_time = dis.rebalance_time; + stats->rebalance_count = dis.rebalance_count; + stats->record_count = dis.record_count; + stats->collision_count = dis.collision_count; + stats->discard_count = dis.discard_count; + stats->overflow_count = dis.overflow_count; + stats->delta_lists = dis.list_count; + stats->early_flushes = 0; + for (z = 0; z < sub_index->zone_count; z++) + stats->early_flushes += sub_index->zones[z].early_flushes; +} + +void uds_get_volume_index_stats(const struct volume_index *volume_index, + struct volume_index_stats *stats) +{ + struct volume_index_stats sparse_stats; + + get_volume_sub_index_stats(&volume_index->vi_non_hook, stats); + if (!has_sparse(volume_index)) + return; + + get_volume_sub_index_stats(&volume_index->vi_hook, &sparse_stats); + stats->rebalance_time += sparse_stats.rebalance_time; + stats->rebalance_count += sparse_stats.rebalance_count; + stats->record_count += sparse_stats.record_count; + stats->collision_count += sparse_stats.collision_count; + stats->discard_count += sparse_stats.discard_count; + stats->overflow_count += sparse_stats.overflow_count; + stats->delta_lists += sparse_stats.delta_lists; + stats->early_flushes += sparse_stats.early_flushes; +} + +static int initialize_volume_sub_index(const struct uds_configuration *config, + u64 volume_nonce, u8 tag, + struct volume_sub_index *sub_index) +{ + struct sub_index_parameters params = { .address_bits = 0 }; + unsigned int zone_count = config->zone_count; + u64 available_bytes = 0; + unsigned int z; + int result; + + result = compute_volume_sub_index_parameters(config, ¶ms); + if (result != UDS_SUCCESS) + return result; + + sub_index->address_bits = params.address_bits; + sub_index->address_mask = (1u << params.address_bits) - 1; + sub_index->chapter_bits = params.chapter_bits; + sub_index->chapter_mask = (1u << params.chapter_bits) - 1; + sub_index->chapter_count = params.chapter_count; + sub_index->list_count = params.list_count; + sub_index->zone_count = zone_count; + sub_index->chapter_zone_bits = params.chapter_size_in_bits / zone_count; + sub_index->volume_nonce = volume_nonce; + + result = uds_initialize_delta_index(&sub_index->delta_index, zone_count, + params.list_count, params.mean_delta, + params.chapter_bits, params.memory_size, + tag); + if (result != UDS_SUCCESS) + return result; + + for (z = 0; z < sub_index->delta_index.zone_count; z++) + available_bytes += sub_index->delta_index.delta_zones[z].size; + available_bytes -= params.target_free_bytes; + sub_index->max_zone_bits = (available_bytes * BITS_PER_BYTE) / zone_count; + sub_index->memory_size = (sub_index->delta_index.memory_size + + sizeof(struct volume_sub_index) + + (params.list_count * sizeof(u64)) + + (zone_count * sizeof(struct volume_sub_index_zone))); + + /* The following arrays are initialized to all zeros. */ + result = vdo_allocate(params.list_count, u64, "first chapter to flush", + &sub_index->flush_chapters); + if (result != VDO_SUCCESS) + return result; + + return vdo_allocate(zone_count, struct volume_sub_index_zone, + "volume index zones", &sub_index->zones); +} + +int uds_make_volume_index(const struct uds_configuration *config, u64 volume_nonce, + struct volume_index **volume_index_ptr) +{ + struct split_config split; + unsigned int zone; + struct volume_index *volume_index; + int result; + + result = vdo_allocate(1, struct volume_index, "volume index", &volume_index); + if (result != VDO_SUCCESS) + return result; + + volume_index->zone_count = config->zone_count; + + if (!uds_is_sparse_index_geometry(config->geometry)) { + result = initialize_volume_sub_index(config, volume_nonce, 'm', + &volume_index->vi_non_hook); + if (result != UDS_SUCCESS) { + uds_free_volume_index(volume_index); + return result; + } + + volume_index->memory_size = volume_index->vi_non_hook.memory_size; + *volume_index_ptr = volume_index; + return UDS_SUCCESS; + } + + volume_index->sparse_sample_rate = config->sparse_sample_rate; + + result = vdo_allocate(config->zone_count, struct volume_index_zone, + "volume index zones", &volume_index->zones); + if (result != VDO_SUCCESS) { + uds_free_volume_index(volume_index); + return result; + } + + for (zone = 0; zone < config->zone_count; zone++) + mutex_init(&volume_index->zones[zone].hook_mutex); + + split_configuration(config, &split); + result = initialize_volume_sub_index(&split.non_hook_config, volume_nonce, 'd', + &volume_index->vi_non_hook); + if (result != UDS_SUCCESS) { + uds_free_volume_index(volume_index); + return vdo_log_error_strerror(result, + "Error creating non hook volume index"); + } + + result = initialize_volume_sub_index(&split.hook_config, volume_nonce, 's', + &volume_index->vi_hook); + if (result != UDS_SUCCESS) { + uds_free_volume_index(volume_index); + return vdo_log_error_strerror(result, + "Error creating hook volume index"); + } + + volume_index->memory_size = + volume_index->vi_non_hook.memory_size + volume_index->vi_hook.memory_size; + *volume_index_ptr = volume_index; + return UDS_SUCCESS; +} |