Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 1 | // Copyright 2020 The Pigweed Authors |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| 4 | // use this file except in compliance with the License. You may obtain a copy of |
| 5 | // the License at |
| 6 | // |
| 7 | // https://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| 11 | // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| 12 | // License for the specific language governing permissions and limitations under |
| 13 | // the License. |
| 14 | |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 15 | #include "pw_kvs/key_value_store.h" |
| 16 | |
Wyatt Hepler | bab0e20 | 2020-02-04 07:40:08 -0800 | [diff] [blame] | 17 | #include <algorithm> |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 18 | #include <cinttypes> |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 19 | #include <cstring> |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 20 | #include <type_traits> |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 21 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 22 | #define PW_LOG_USE_ULTRA_SHORT_NAMES 1 |
Wyatt Hepler | bdd8e5a | 2020-02-20 19:27:26 -0800 | [diff] [blame] | 23 | #include "pw_kvs/internal/entry.h" |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 24 | #include "pw_kvs_private/macros.h" |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 25 | #include "pw_log/log.h" |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 26 | |
Wyatt Hepler | 2ad6067 | 2020-01-21 08:00:16 -0800 | [diff] [blame] | 27 | namespace pw::kvs { |
Wyatt Hepler | a00d1ef | 2020-02-14 14:31:26 -0800 | [diff] [blame] | 28 | namespace { |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 29 | |
Wyatt Hepler | acaacf9 | 2020-01-24 10:58:30 -0800 | [diff] [blame] | 30 | using std::byte; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 31 | using std::string_view; |
Wyatt Hepler | acaacf9 | 2020-01-24 10:58:30 -0800 | [diff] [blame] | 32 | |
Wyatt Hepler | a00d1ef | 2020-02-14 14:31:26 -0800 | [diff] [blame] | 33 | constexpr bool InvalidKey(std::string_view key) { |
Wyatt Hepler | bdd8e5a | 2020-02-20 19:27:26 -0800 | [diff] [blame] | 34 | return key.empty() || (key.size() > internal::Entry::kMaxKeyLength); |
Wyatt Hepler | a00d1ef | 2020-02-14 14:31:26 -0800 | [diff] [blame] | 35 | } |
| 36 | |
| 37 | } // namespace |
| 38 | |
Wyatt Hepler | ad0a793 | 2020-02-06 08:20:38 -0800 | [diff] [blame] | 39 | KeyValueStore::KeyValueStore(FlashPartition* partition, |
Wyatt Hepler | 38ce30f | 2020-02-19 11:48:31 -0800 | [diff] [blame] | 40 | Vector<KeyDescriptor>& key_descriptor_list, |
| 41 | Vector<SectorDescriptor>& sector_descriptor_list, |
Wyatt Hepler | 88adfe8 | 2020-02-20 19:33:27 -0800 | [diff] [blame] | 42 | const EntryFormat& format, |
Wyatt Hepler | ad0a793 | 2020-02-06 08:20:38 -0800 | [diff] [blame] | 43 | const Options& options) |
| 44 | : partition_(*partition), |
| 45 | entry_header_format_(format), |
Wyatt Hepler | 38ce30f | 2020-02-19 11:48:31 -0800 | [diff] [blame] | 46 | key_descriptors_(key_descriptor_list), |
Wyatt Hepler | d229828 | 2020-02-20 17:12:45 -0800 | [diff] [blame] | 47 | sectors_(sector_descriptor_list), |
| 48 | options_(options) { |
| 49 | Reset(); |
| 50 | } |
Wyatt Hepler | ad0a793 | 2020-02-06 08:20:38 -0800 | [diff] [blame] | 51 | |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 52 | Status KeyValueStore::Init() { |
Wyatt Hepler | d229828 | 2020-02-20 17:12:45 -0800 | [diff] [blame] | 53 | Reset(); |
| 54 | |
David Rogers | 2e9e0c8 | 2020-02-13 15:06:06 -0800 | [diff] [blame] | 55 | INF("Initializing key value store"); |
Wyatt Hepler | 38ce30f | 2020-02-19 11:48:31 -0800 | [diff] [blame] | 56 | if (partition_.sector_count() > sectors_.max_size()) { |
David Rogers | 2e9e0c8 | 2020-02-13 15:06:06 -0800 | [diff] [blame] | 57 | ERR("KVS init failed: kMaxUsableSectors (=%zu) must be at least as " |
| 58 | "large as the number of sectors in the flash partition (=%zu)", |
Wyatt Hepler | 38ce30f | 2020-02-19 11:48:31 -0800 | [diff] [blame] | 59 | sectors_.max_size(), |
David Rogers | 2e9e0c8 | 2020-02-13 15:06:06 -0800 | [diff] [blame] | 60 | partition_.sector_count()); |
Wyatt Hepler | ad0a793 | 2020-02-06 08:20:38 -0800 | [diff] [blame] | 61 | return Status::FAILED_PRECONDITION; |
| 62 | } |
| 63 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 64 | const size_t sector_size_bytes = partition_.sector_size_bytes(); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 65 | |
David Rogers | f0a3544 | 2020-02-04 12:16:38 -0800 | [diff] [blame] | 66 | if (working_buffer_.size() < sector_size_bytes) { |
Wyatt Hepler | ce7b8df | 2020-02-21 10:38:39 -0800 | [diff] [blame] | 67 | ERR("KVS init failed: working_buffer_ (%zu B) is smaller than sector size " |
| 68 | "(%zu B)", |
David Rogers | f0a3544 | 2020-02-04 12:16:38 -0800 | [diff] [blame] | 69 | working_buffer_.size(), |
| 70 | sector_size_bytes); |
| 71 | return Status::INVALID_ARGUMENT; |
| 72 | } |
| 73 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 74 | DBG("First pass: Read all entries from all sectors"); |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 75 | Address sector_address = 0; |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 76 | |
Wyatt Hepler | d229828 | 2020-02-20 17:12:45 -0800 | [diff] [blame] | 77 | sectors_.assign(partition_.sector_count(), |
| 78 | SectorDescriptor(sector_size_bytes)); |
| 79 | |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 80 | size_t total_corrupt_bytes = 0; |
| 81 | int corrupt_entries = 0; |
David Rogers | 9162748 | 2020-02-27 17:38:12 -0800 | [diff] [blame] | 82 | bool empty_sector_found = false; |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 83 | |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 84 | for (SectorDescriptor& sector : sectors_) { |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 85 | Address entry_address = sector_address; |
| 86 | |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 87 | size_t sector_corrupt_bytes = 0; |
| 88 | |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 89 | for (int num_entries_in_sector = 0; true; num_entries_in_sector++) { |
| 90 | DBG("Load entry: sector=%" PRIx32 ", entry#=%d, address=%" PRIx32, |
| 91 | sector_address, |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 92 | num_entries_in_sector, |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 93 | entry_address); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 94 | |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 95 | if (!AddressInSector(sector, entry_address)) { |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 96 | DBG("Fell off end of sector; moving to the next sector"); |
| 97 | break; |
| 98 | } |
| 99 | |
| 100 | Address next_entry_address; |
| 101 | Status status = LoadEntry(entry_address, &next_entry_address); |
| 102 | if (status == Status::NOT_FOUND) { |
| 103 | DBG("Hit un-written data in sector; moving to the next sector"); |
| 104 | break; |
| 105 | } |
| 106 | if (status == Status::DATA_LOSS) { |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 107 | // The entry could not be read, indicating data corruption within the |
| 108 | // sector. Try to scan the remainder of the sector for other entries. |
| 109 | ERR("KVS init: data loss detected in sector %u at address %zu", |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 110 | SectorIndex(§or), |
| 111 | size_t(entry_address)); |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 112 | |
| 113 | corrupt_entries++; |
| 114 | |
| 115 | status = ScanForEntry(sector, |
| 116 | entry_address + Entry::kMinAlignmentBytes, |
| 117 | &next_entry_address); |
| 118 | if (status == Status::NOT_FOUND) { |
| 119 | // No further entries in this sector. Mark the remaining bytes in the |
| 120 | // sector as corrupt (since we can't reliably know the size of the |
| 121 | // corrupt entry). |
| 122 | sector_corrupt_bytes += |
| 123 | sector_size_bytes - (entry_address - sector_address); |
| 124 | break; |
| 125 | } |
| 126 | |
| 127 | if (!status.ok()) { |
| 128 | ERR("Unexpected error in KVS initialization: %s", status.str()); |
| 129 | return Status::UNKNOWN; |
| 130 | } |
| 131 | |
| 132 | sector_corrupt_bytes += next_entry_address - entry_address; |
| 133 | } else if (!status.ok()) { |
| 134 | ERR("Unexpected error in KVS initialization: %s", status.str()); |
| 135 | return Status::UNKNOWN; |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 136 | } |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 137 | |
| 138 | // Entry loaded successfully; so get ready to load the next one. |
| 139 | entry_address = next_entry_address; |
| 140 | |
| 141 | // Update of the number of writable bytes in this sector. |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 142 | sector.set_writable_bytes(sector_size_bytes - |
| 143 | (entry_address - sector_address)); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 144 | } |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 145 | |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 146 | if (sector_corrupt_bytes > 0) { |
| 147 | // If the sector contains corrupt data, prevent any further entries from |
| 148 | // being written to it by indicating that it has no space. This should |
| 149 | // also make it a decent GC candidate. Valid keys in the sector are still |
| 150 | // readable as normal. |
| 151 | sector.set_writable_bytes(0); |
| 152 | |
| 153 | WRN("Sector %u contains %zuB of corrupt data", |
| 154 | SectorIndex(§or), |
| 155 | sector_corrupt_bytes); |
| 156 | } |
| 157 | |
David Rogers | 9162748 | 2020-02-27 17:38:12 -0800 | [diff] [blame] | 158 | if (sector.Empty(sector_size_bytes)) { |
| 159 | empty_sector_found = true; |
| 160 | } |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 161 | sector_address += sector_size_bytes; |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 162 | total_corrupt_bytes += sector_corrupt_bytes; |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 163 | } |
| 164 | |
| 165 | DBG("Second pass: Count valid bytes in each sector"); |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 166 | const KeyDescriptor* newest_key = nullptr; |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 167 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 168 | // For every valid key, increment the valid bytes for that sector. |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 169 | for (KeyDescriptor& key_descriptor : key_descriptors_) { |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 170 | for (auto& address : key_descriptor.addresses()) { |
| 171 | Entry entry; |
| 172 | TRY(Entry::Read(partition_, address, &entry)); |
| 173 | SectorFromAddress(address)->AddValidBytes(entry.size()); |
| 174 | } |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 175 | if (key_descriptor.IsNewerThan(last_transaction_id_)) { |
| 176 | last_transaction_id_ = key_descriptor.transaction_id(); |
| 177 | newest_key = &key_descriptor; |
| 178 | } |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 179 | } |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 180 | |
| 181 | if (newest_key == nullptr) { |
| 182 | last_new_sector_ = sectors_.begin(); |
| 183 | } else { |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 184 | last_new_sector_ = SectorFromAddress(newest_key->addresses().back()); |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 185 | } |
| 186 | |
David Rogers | 9162748 | 2020-02-27 17:38:12 -0800 | [diff] [blame] | 187 | if (!empty_sector_found) { |
| 188 | // TODO: Record/report the error condition and recovery result. |
| 189 | Status gc_result = GarbageCollectPartial(); |
| 190 | |
| 191 | if (!gc_result.ok()) { |
| 192 | ERR("KVS init failed: Unable to maintain required free sector"); |
| 193 | return Status::INTERNAL; |
| 194 | } |
| 195 | } |
| 196 | |
Wyatt Hepler | 729f28c | 2020-02-05 09:46:00 -0800 | [diff] [blame] | 197 | initialized_ = true; |
David Rogers | 2e9e0c8 | 2020-02-13 15:06:06 -0800 | [diff] [blame] | 198 | |
Armando Montanez | 5464d5f | 2020-02-20 10:12:20 -0800 | [diff] [blame] | 199 | INF("KeyValueStore init complete: active keys %zu, deleted keys %zu, sectors " |
David Rogers | 2e9e0c8 | 2020-02-13 15:06:06 -0800 | [diff] [blame] | 200 | "%zu, logical sector size %zu bytes", |
| 201 | size(), |
| 202 | (key_descriptors_.size() - size()), |
| 203 | sectors_.size(), |
| 204 | partition_.sector_size_bytes()); |
| 205 | |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 206 | if (total_corrupt_bytes > 0) { |
| 207 | WRN("Found %zu corrupt bytes and %d corrupt entries during init process; " |
| 208 | "some keys may be missing", |
| 209 | total_corrupt_bytes, |
| 210 | corrupt_entries); |
| 211 | return Status::DATA_LOSS; |
| 212 | } |
| 213 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 214 | return Status::OK; |
| 215 | } |
| 216 | |
Alexei Frolov | 9e23583 | 2020-02-24 12:44:45 -0800 | [diff] [blame] | 217 | KeyValueStore::StorageStats KeyValueStore::GetStorageStats() const { |
| 218 | StorageStats stats{0, 0, 0}; |
| 219 | const size_t sector_size = partition_.sector_size_bytes(); |
| 220 | bool found_empty_sector = false; |
| 221 | |
| 222 | for (const SectorDescriptor& sector : sectors_) { |
| 223 | stats.in_use_bytes += sector.valid_bytes(); |
| 224 | stats.reclaimable_bytes += sector.RecoverableBytes(sector_size); |
| 225 | |
| 226 | if (!found_empty_sector && sector.Empty(sector_size)) { |
| 227 | // The KVS tries to always keep an empty sector for GC, so don't count |
| 228 | // the first empty sector seen as writable space. However, a free sector |
| 229 | // cannot always be assumed to exist; if a GC operation fails, all sectors |
| 230 | // may be partially written, in which case the space reported might be |
| 231 | // inaccurate. |
| 232 | found_empty_sector = true; |
| 233 | continue; |
| 234 | } |
| 235 | |
| 236 | stats.writable_bytes += sector.writable_bytes(); |
| 237 | } |
| 238 | |
| 239 | return stats; |
| 240 | } |
| 241 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 242 | Status KeyValueStore::LoadEntry(Address entry_address, |
| 243 | Address* next_entry_address) { |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 244 | Entry entry; |
| 245 | TRY(Entry::Read(partition_, entry_address, &entry)); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 246 | |
| 247 | // TODO: Handle multiple magics for formats that have changed. |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 248 | if (entry.magic() != entry_header_format_.magic) { |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 249 | // TODO: It may be cleaner to have some logging helpers for these cases. |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 250 | ERR("Found corrupt magic: %zx; expecting %zx; at address %zx", |
| 251 | size_t(entry.magic()), |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 252 | size_t(entry_header_format_.magic), |
| 253 | size_t(entry_address)); |
| 254 | return Status::DATA_LOSS; |
| 255 | } |
| 256 | |
| 257 | // Read the key from flash & validate the entry (which reads the value). |
Wyatt Hepler | a00d1ef | 2020-02-14 14:31:26 -0800 | [diff] [blame] | 258 | Entry::KeyBuffer key_buffer; |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 259 | TRY_ASSIGN(size_t key_length, entry.ReadKey(key_buffer)); |
| 260 | const string_view key(key_buffer.data(), key_length); |
Wyatt Hepler | bab0e20 | 2020-02-04 07:40:08 -0800 | [diff] [blame] | 261 | |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 262 | TRY(entry.VerifyChecksumInFlash(entry_header_format_.checksum)); |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 263 | |
| 264 | // A valid entry was found, so update the next entry address before doing any |
| 265 | // of the checks that happen in AppendNewOrOverwriteStaleExistingDescriptor(). |
| 266 | *next_entry_address = entry.next_address(); |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 267 | TRY(AppendNewOrOverwriteStaleExistingDescriptor(entry.descriptor(key))); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 268 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 269 | return Status::OK; |
| 270 | } |
| 271 | |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 272 | // Scans flash memory within a sector to find a KVS entry magic. |
Alexei Frolov | d4adf91 | 2020-02-21 13:29:15 -0800 | [diff] [blame] | 273 | Status KeyValueStore::ScanForEntry(const SectorDescriptor& sector, |
| 274 | Address start_address, |
| 275 | Address* next_entry_address) { |
| 276 | DBG("Scanning sector %u for entries starting from address %zx", |
| 277 | SectorIndex(§or), |
| 278 | size_t(start_address)); |
| 279 | |
| 280 | // Entries must start at addresses which are aligned on a multiple of |
| 281 | // Entry::kMinAlignmentBytes. However, that multiple can vary between entries. |
| 282 | // When scanning, we don't have an entry to tell us what the current alignment |
| 283 | // is, so the minimum alignment is used to be exhaustive. |
| 284 | for (Address address = AlignUp(start_address, Entry::kMinAlignmentBytes); |
| 285 | AddressInSector(sector, address); |
| 286 | address += Entry::kMinAlignmentBytes) { |
| 287 | // TODO: Handle multiple magics for formats that have changed. |
| 288 | uint32_t magic; |
| 289 | TRY(partition_.Read(address, as_writable_bytes(span(&magic, 1)))); |
| 290 | if (magic == entry_header_format_.magic) { |
| 291 | DBG("Found entry magic at address %zx", size_t(address)); |
| 292 | *next_entry_address = address; |
| 293 | return Status::OK; |
| 294 | } |
| 295 | } |
| 296 | |
| 297 | return Status::NOT_FOUND; |
| 298 | } |
| 299 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 300 | // TODO: This method is the trigger of the O(valid_entries * all_entries) time |
| 301 | // complexity for reading. At some cost to memory, this could be optimized by |
| 302 | // using a hash table instead of scanning, but in practice this should be fine |
| 303 | // for a small number of keys |
| 304 | Status KeyValueStore::AppendNewOrOverwriteStaleExistingDescriptor( |
| 305 | const KeyDescriptor& key_descriptor) { |
| 306 | // With the new key descriptor, either add it to the descriptor table or |
| 307 | // overwrite an existing entry with an older version of the key. |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 308 | KeyDescriptor* existing_descriptor = FindDescriptor(key_descriptor.hash()); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 309 | |
Wyatt Hepler | 5406a67 | 2020-02-18 15:42:38 -0800 | [diff] [blame] | 310 | // Write a new entry. |
| 311 | if (existing_descriptor == nullptr) { |
| 312 | if (key_descriptors_.full()) { |
| 313 | return Status::RESOURCE_EXHAUSTED; |
| 314 | } |
| 315 | key_descriptors_.push_back(key_descriptor); |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 316 | } else if (key_descriptor.IsNewerThan( |
| 317 | existing_descriptor->transaction_id())) { |
Wyatt Hepler | 5406a67 | 2020-02-18 15:42:38 -0800 | [diff] [blame] | 318 | // Existing entry is old; replace the existing entry with the new one. |
| 319 | *existing_descriptor = key_descriptor; |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 320 | } else if (existing_descriptor->transaction_id() == |
| 321 | key_descriptor.transaction_id()) { |
| 322 | // If the entries have a duplicate transaction ID, add the new (redundant) |
| 323 | // entry to the existing descriptor. |
| 324 | if (existing_descriptor->hash() != key_descriptor.hash()) { |
| 325 | ERR("Duplicate entry for key %#010" PRIx32 " with transaction ID %" PRIu32 |
| 326 | " has non-matching hash", |
| 327 | key_descriptor.hash(), |
| 328 | key_descriptor.transaction_id()); |
Wyatt Hepler | 5406a67 | 2020-02-18 15:42:38 -0800 | [diff] [blame] | 329 | return Status::DATA_LOSS; |
| 330 | } |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 331 | |
| 332 | // Verify that this entry is not in the same sector as an existing copy of |
| 333 | // this same key. |
| 334 | for (auto address : existing_descriptor->addresses()) { |
| 335 | if (SectorFromAddress(address) == |
| 336 | SectorFromAddress(key_descriptor.address())) { |
| 337 | DBG("Multiple Redundant entries in same sector %u", |
| 338 | SectorIndex(SectorFromAddress(address))); |
| 339 | return Status::DATA_LOSS; |
| 340 | } |
| 341 | } |
| 342 | existing_descriptor->addresses().push_back(key_descriptor.address()); |
| 343 | } else { |
Wyatt Hepler | 5406a67 | 2020-02-18 15:42:38 -0800 | [diff] [blame] | 344 | DBG("Found stale entry when appending; ignoring"); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 345 | } |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 346 | return Status::OK; |
| 347 | } |
| 348 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 349 | KeyValueStore::KeyDescriptor* KeyValueStore::FindDescriptor(uint32_t hash) { |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 350 | for (KeyDescriptor& key_descriptor : key_descriptors_) { |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 351 | if (key_descriptor.hash() == hash) { |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 352 | return &key_descriptor; |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 353 | } |
| 354 | } |
| 355 | return nullptr; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 356 | } |
| 357 | |
| 358 | StatusWithSize KeyValueStore::Get(string_view key, |
Wyatt Hepler | 5f6efc0 | 2020-02-18 16:54:31 -0800 | [diff] [blame] | 359 | span<byte> value_buffer, |
| 360 | size_t offset_bytes) const { |
Wyatt Hepler | 50f7077 | 2020-02-13 11:25:10 -0800 | [diff] [blame] | 361 | TRY_WITH_SIZE(CheckOperation(key)); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 362 | |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 363 | const KeyDescriptor* key_descriptor; |
Wyatt Hepler | 2d40169 | 2020-02-13 16:01:23 -0800 | [diff] [blame] | 364 | TRY_WITH_SIZE(FindExistingKeyDescriptor(key, &key_descriptor)); |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 365 | |
Wyatt Hepler | fac8113 | 2020-02-27 17:26:33 -0800 | [diff] [blame] | 366 | return Get(key, *key_descriptor, value_buffer, offset_bytes); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 367 | } |
| 368 | |
Wyatt Hepler | fac8113 | 2020-02-27 17:26:33 -0800 | [diff] [blame] | 369 | Status KeyValueStore::PutBytes(string_view key, span<const byte> value) { |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 370 | DBG("Writing key/value; key length=%zu, value length=%zu", |
| 371 | key.size(), |
| 372 | value.size()); |
Wyatt Hepler | 729f28c | 2020-02-05 09:46:00 -0800 | [diff] [blame] | 373 | |
| 374 | TRY(CheckOperation(key)); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 375 | |
Wyatt Hepler | 5406a67 | 2020-02-18 15:42:38 -0800 | [diff] [blame] | 376 | if (Entry::size(partition_, key, value) > partition_.sector_size_bytes()) { |
| 377 | DBG("%zu B value with %zu B key cannot fit in one sector", |
| 378 | value.size(), |
| 379 | key.size()); |
| 380 | return Status::INVALID_ARGUMENT; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 381 | } |
| 382 | |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 383 | KeyDescriptor* key_descriptor; |
Wyatt Hepler | 2d40169 | 2020-02-13 16:01:23 -0800 | [diff] [blame] | 384 | Status status = FindKeyDescriptor(key, &key_descriptor); |
| 385 | |
| 386 | if (status.ok()) { |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 387 | // TODO: figure out logging how to support multiple addresses. |
| 388 | DBG("Overwriting entry for key %#08" PRIx32 " in %u sectors including %u", |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 389 | key_descriptor->hash(), |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 390 | unsigned(key_descriptor->addresses().size()), |
| 391 | SectorIndex(SectorFromAddress(key_descriptor->address()))); |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 392 | return WriteEntryForExistingKey( |
| 393 | key_descriptor, KeyDescriptor::kValid, key, value); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 394 | } |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 395 | |
Wyatt Hepler | 2d40169 | 2020-02-13 16:01:23 -0800 | [diff] [blame] | 396 | if (status == Status::NOT_FOUND) { |
| 397 | return WriteEntryForNewKey(key, value); |
| 398 | } |
| 399 | |
| 400 | return status; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 401 | } |
| 402 | |
| 403 | Status KeyValueStore::Delete(string_view key) { |
Wyatt Hepler | 729f28c | 2020-02-05 09:46:00 -0800 | [diff] [blame] | 404 | TRY(CheckOperation(key)); |
| 405 | |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 406 | KeyDescriptor* key_descriptor; |
Wyatt Hepler | 2d40169 | 2020-02-13 16:01:23 -0800 | [diff] [blame] | 407 | TRY(FindExistingKeyDescriptor(key, &key_descriptor)); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 408 | |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 409 | // TODO: figure out logging how to support multiple addresses. |
| 410 | DBG("Writing tombstone for key %#08" PRIx32 " in %u sectors including %u", |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 411 | key_descriptor->hash(), |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 412 | unsigned(key_descriptor->addresses().size()), |
| 413 | SectorIndex(SectorFromAddress(key_descriptor->address()))); |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 414 | return WriteEntryForExistingKey( |
| 415 | key_descriptor, KeyDescriptor::kDeleted, key, {}); |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 416 | } |
| 417 | |
Wyatt Hepler | 08d37d8 | 2020-02-27 15:45:37 -0800 | [diff] [blame] | 418 | void KeyValueStore::Item::ReadKey() { |
| 419 | key_buffer_.fill('\0'); |
| 420 | |
| 421 | Entry entry; |
| 422 | if (Entry::Read(kvs_.partition_, descriptor_->address(), &entry).ok()) { |
| 423 | entry.ReadKey(key_buffer_); |
| 424 | } |
| 425 | } |
| 426 | |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 427 | KeyValueStore::iterator& KeyValueStore::iterator::operator++() { |
| 428 | // Skip to the next entry that is valid (not deleted). |
Wyatt Hepler | 08d37d8 | 2020-02-27 15:45:37 -0800 | [diff] [blame] | 429 | while (++item_.descriptor_ != item_.kvs_.key_descriptors_.end() && |
| 430 | item_.descriptor_->deleted()) { |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 431 | } |
| 432 | return *this; |
| 433 | } |
| 434 | |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 435 | KeyValueStore::iterator KeyValueStore::begin() const { |
Wyatt Hepler | 08d37d8 | 2020-02-27 15:45:37 -0800 | [diff] [blame] | 436 | const KeyDescriptor* descriptor = key_descriptors_.begin(); |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 437 | // Skip over any deleted entries at the start of the descriptor list. |
Wyatt Hepler | 08d37d8 | 2020-02-27 15:45:37 -0800 | [diff] [blame] | 438 | while (descriptor != key_descriptors_.end() && descriptor->deleted()) { |
| 439 | ++descriptor; |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 440 | } |
Wyatt Hepler | 08d37d8 | 2020-02-27 15:45:37 -0800 | [diff] [blame] | 441 | return iterator(*this, descriptor); |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 442 | } |
| 443 | |
| 444 | // TODO(hepler): The valid entry count could be tracked in the KVS to avoid the |
| 445 | // need for this for-loop. |
| 446 | size_t KeyValueStore::size() const { |
| 447 | size_t valid_entries = 0; |
| 448 | |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 449 | for (const KeyDescriptor& key_descriptor : key_descriptors_) { |
| 450 | if (!key_descriptor.deleted()) { |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 451 | valid_entries += 1; |
| 452 | } |
| 453 | } |
| 454 | |
| 455 | return valid_entries; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 456 | } |
| 457 | |
Wyatt Hepler | ed163b0 | 2020-02-03 17:49:32 -0800 | [diff] [blame] | 458 | StatusWithSize KeyValueStore::ValueSize(std::string_view key) const { |
Wyatt Hepler | 50f7077 | 2020-02-13 11:25:10 -0800 | [diff] [blame] | 459 | TRY_WITH_SIZE(CheckOperation(key)); |
Wyatt Hepler | ed163b0 | 2020-02-03 17:49:32 -0800 | [diff] [blame] | 460 | |
| 461 | const KeyDescriptor* key_descriptor; |
Wyatt Hepler | 2d40169 | 2020-02-13 16:01:23 -0800 | [diff] [blame] | 462 | TRY_WITH_SIZE(FindExistingKeyDescriptor(key, &key_descriptor)); |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 463 | |
Wyatt Hepler | fac8113 | 2020-02-27 17:26:33 -0800 | [diff] [blame] | 464 | return ValueSize(*key_descriptor); |
| 465 | } |
Wyatt Hepler | ed163b0 | 2020-02-03 17:49:32 -0800 | [diff] [blame] | 466 | |
Wyatt Hepler | fac8113 | 2020-02-27 17:26:33 -0800 | [diff] [blame] | 467 | StatusWithSize KeyValueStore::Get(string_view key, |
| 468 | const KeyDescriptor& descriptor, |
| 469 | span<std::byte> value_buffer, |
| 470 | size_t offset_bytes) const { |
| 471 | Entry entry; |
| 472 | TRY_WITH_SIZE(Entry::Read(partition_, descriptor.address(), &entry)); |
| 473 | |
| 474 | StatusWithSize result = entry.ReadValue(value_buffer, offset_bytes); |
| 475 | if (result.ok() && options_.verify_on_read && offset_bytes == 0u) { |
| 476 | Status verify_result = entry.VerifyChecksum( |
| 477 | entry_header_format_.checksum, key, value_buffer.first(result.size())); |
| 478 | if (!verify_result.ok()) { |
| 479 | std::memset(value_buffer.data(), 0, result.size()); |
| 480 | return StatusWithSize(verify_result, 0); |
| 481 | } |
| 482 | |
| 483 | return StatusWithSize(verify_result, result.size()); |
| 484 | } |
| 485 | return result; |
Wyatt Hepler | ed163b0 | 2020-02-03 17:49:32 -0800 | [diff] [blame] | 486 | } |
| 487 | |
Wyatt Hepler | 6e3a83b | 2020-02-04 07:36:45 -0800 | [diff] [blame] | 488 | Status KeyValueStore::FixedSizeGet(std::string_view key, |
Wyatt Hepler | fac8113 | 2020-02-27 17:26:33 -0800 | [diff] [blame] | 489 | void* value, |
| 490 | size_t size_bytes) const { |
| 491 | TRY(CheckOperation(key)); |
| 492 | |
| 493 | const KeyDescriptor* descriptor; |
| 494 | TRY(FindExistingKeyDescriptor(key, &descriptor)); |
| 495 | |
| 496 | return FixedSizeGet(key, *descriptor, value, size_bytes); |
| 497 | } |
| 498 | |
| 499 | Status KeyValueStore::FixedSizeGet(std::string_view key, |
| 500 | const KeyDescriptor& descriptor, |
| 501 | void* value, |
Wyatt Hepler | 6e3a83b | 2020-02-04 07:36:45 -0800 | [diff] [blame] | 502 | size_t size_bytes) const { |
| 503 | // Ensure that the size of the stored value matches the size of the type. |
| 504 | // Otherwise, report error. This check avoids potential memory corruption. |
Wyatt Hepler | fac8113 | 2020-02-27 17:26:33 -0800 | [diff] [blame] | 505 | TRY_ASSIGN(const size_t actual_size, ValueSize(descriptor)); |
| 506 | |
| 507 | if (actual_size != size_bytes) { |
| 508 | DBG("Requested %zu B read, but value is %zu B", size_bytes, actual_size); |
Wyatt Hepler | 6e3a83b | 2020-02-04 07:36:45 -0800 | [diff] [blame] | 509 | return Status::INVALID_ARGUMENT; |
Wyatt Hepler | bab0e20 | 2020-02-04 07:40:08 -0800 | [diff] [blame] | 510 | } |
Wyatt Hepler | fac8113 | 2020-02-27 17:26:33 -0800 | [diff] [blame] | 511 | |
| 512 | StatusWithSize result = |
| 513 | Get(key, descriptor, span(static_cast<byte*>(value), size_bytes), 0); |
| 514 | |
| 515 | return result.status(); |
| 516 | } |
| 517 | |
| 518 | StatusWithSize KeyValueStore::ValueSize(const KeyDescriptor& descriptor) const { |
| 519 | Entry entry; |
| 520 | TRY_WITH_SIZE(Entry::Read(partition_, descriptor.address(), &entry)); |
| 521 | |
| 522 | return StatusWithSize(entry.value_size()); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 523 | } |
| 524 | |
Wyatt Hepler | 729f28c | 2020-02-05 09:46:00 -0800 | [diff] [blame] | 525 | Status KeyValueStore::CheckOperation(string_view key) const { |
Wyatt Hepler | acaacf9 | 2020-01-24 10:58:30 -0800 | [diff] [blame] | 526 | if (InvalidKey(key)) { |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 527 | return Status::INVALID_ARGUMENT; |
| 528 | } |
Wyatt Hepler | d229828 | 2020-02-20 17:12:45 -0800 | [diff] [blame] | 529 | if (!initialized()) { |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 530 | return Status::FAILED_PRECONDITION; |
| 531 | } |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 532 | return Status::OK; |
| 533 | } |
| 534 | |
Wyatt Hepler | 2d40169 | 2020-02-13 16:01:23 -0800 | [diff] [blame] | 535 | // Searches for a KeyDescriptor that matches this key and sets *result to point |
| 536 | // to it if one is found. |
| 537 | // |
| 538 | // OK: there is a matching descriptor and *result is set |
| 539 | // NOT_FOUND: there is no descriptor that matches this key, but this key |
| 540 | // has a unique hash (and could potentially be added to the KVS) |
| 541 | // ALREADY_EXISTS: there is no descriptor that matches this key, but the |
| 542 | // key's hash collides with the hash for an existing descriptor |
| 543 | // |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 544 | Status KeyValueStore::FindKeyDescriptor(string_view key, |
| 545 | const KeyDescriptor** result) const { |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 546 | const uint32_t hash = internal::Hash(key); |
Wyatt Hepler | a00d1ef | 2020-02-14 14:31:26 -0800 | [diff] [blame] | 547 | Entry::KeyBuffer key_buffer; |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 548 | |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 549 | for (auto& descriptor : key_descriptors_) { |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 550 | if (descriptor.hash() == hash) { |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 551 | TRY(Entry::ReadKey( |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 552 | partition_, descriptor.address(), key.size(), key_buffer.data())); |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 553 | |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 554 | if (key == string_view(key_buffer.data(), key.size())) { |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 555 | DBG("Found match for key hash 0x%08" PRIx32, hash); |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 556 | *result = &descriptor; |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 557 | return Status::OK; |
Wyatt Hepler | 2d40169 | 2020-02-13 16:01:23 -0800 | [diff] [blame] | 558 | } else { |
| 559 | WRN("Found key hash collision for 0x%08" PRIx32, hash); |
| 560 | return Status::ALREADY_EXISTS; |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 561 | } |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 562 | } |
| 563 | } |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 564 | return Status::NOT_FOUND; |
| 565 | } |
| 566 | |
Wyatt Hepler | 2d40169 | 2020-02-13 16:01:23 -0800 | [diff] [blame] | 567 | // Searches for a KeyDescriptor that matches this key and sets *result to point |
| 568 | // to it if one is found. |
| 569 | // |
| 570 | // OK: there is a matching descriptor and *result is set |
| 571 | // NOT_FOUND: there is no descriptor that matches this key |
| 572 | // |
| 573 | Status KeyValueStore::FindExistingKeyDescriptor( |
| 574 | string_view key, const KeyDescriptor** result) const { |
| 575 | Status status = FindKeyDescriptor(key, result); |
| 576 | |
| 577 | // If the key's hash collides with an existing key or if the key is deleted, |
| 578 | // treat it as if it is not in the KVS. |
| 579 | if (status == Status::ALREADY_EXISTS || |
| 580 | (status.ok() && (*result)->deleted())) { |
| 581 | return Status::NOT_FOUND; |
| 582 | } |
| 583 | return status; |
| 584 | } |
| 585 | |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 586 | Status KeyValueStore::WriteEntryForExistingKey(KeyDescriptor* key_descriptor, |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 587 | KeyDescriptor::State new_state, |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 588 | string_view key, |
| 589 | span<const byte> value) { |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 590 | // Find the original entry and sector to update the sector's valid_bytes. |
Wyatt Hepler | 30a5215 | 2020-02-12 11:26:05 -0800 | [diff] [blame] | 591 | Entry original_entry; |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 592 | TRY(Entry::Read(partition_, key_descriptor->address(), &original_entry)); |
Wyatt Hepler | 6c24c06 | 2020-02-05 15:30:49 -0800 | [diff] [blame] | 593 | |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 594 | SectorDescriptor* sector; |
Wyatt Hepler | 5406a67 | 2020-02-18 15:42:38 -0800 | [diff] [blame] | 595 | TRY(FindOrRecoverSectorWithSpace(§or, |
| 596 | Entry::size(partition_, key, value))); |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 597 | DBG("Writing existing entry; found sector %u (%#" PRIx32 ")", |
| 598 | SectorIndex(sector), |
| 599 | SectorBaseAddress(sector)); |
David Rogers | 3464d0a | 2020-02-07 11:45:46 -0800 | [diff] [blame] | 600 | |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 601 | // TODO: Verify the copy does a full copy including the address vector. |
| 602 | KeyDescriptor old_key_descriptor = *key_descriptor; |
David Rogers | 3464d0a | 2020-02-07 11:45:46 -0800 | [diff] [blame] | 603 | |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 604 | TRY(AppendEntry(sector, key_descriptor, key, value, new_state)); |
| 605 | |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 606 | for (auto& address : old_key_descriptor.addresses()) { |
| 607 | SectorFromAddress(address)->RemoveValidBytes(original_entry.size()); |
| 608 | } |
| 609 | |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 610 | return Status::OK; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 611 | } |
| 612 | |
| 613 | Status KeyValueStore::WriteEntryForNewKey(string_view key, |
| 614 | span<const byte> value) { |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 615 | if (key_descriptors_.full()) { |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 616 | WRN("KVS full: trying to store a new entry, but can't. Have %zu entries", |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 617 | key_descriptors_.size()); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 618 | return Status::RESOURCE_EXHAUSTED; |
| 619 | } |
| 620 | |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 621 | SectorDescriptor* sector; |
Wyatt Hepler | 5406a67 | 2020-02-18 15:42:38 -0800 | [diff] [blame] | 622 | TRY(FindOrRecoverSectorWithSpace(§or, |
| 623 | Entry::size(partition_, key, value))); |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 624 | DBG("Writing new entry; found sector: %u", SectorIndex(sector)); |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 625 | |
| 626 | // Create the KeyDescriptor that will be added to the list. The transaction ID |
| 627 | // and address will be set by AppendEntry. |
| 628 | KeyDescriptor key_descriptor(key); |
Wyatt Hepler | 0af6ad9 | 2020-02-13 15:54:46 -0800 | [diff] [blame] | 629 | TRY(AppendEntry(sector, &key_descriptor, key, value, KeyDescriptor::kValid)); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 630 | |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 631 | // Only add the entry when we are certain the write succeeded. |
| 632 | key_descriptors_.push_back(key_descriptor); |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 633 | return Status::OK; |
| 634 | } |
| 635 | |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 636 | Status KeyValueStore::RelocateEntry(KeyDescriptor& key_descriptor, |
| 637 | KeyValueStore::Address address) { |
David Rogers | f0a3544 | 2020-02-04 12:16:38 -0800 | [diff] [blame] | 638 | struct TempEntry { |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 639 | Entry::KeyBuffer key; |
Wyatt Hepler | ce7b8df | 2020-02-21 10:38:39 -0800 | [diff] [blame] | 640 | std::array<byte, sizeof(working_buffer_) - sizeof(key)> value; |
David Rogers | f0a3544 | 2020-02-04 12:16:38 -0800 | [diff] [blame] | 641 | }; |
Wyatt Hepler | ce7b8df | 2020-02-21 10:38:39 -0800 | [diff] [blame] | 642 | auto [key_buffer, value_buffer] = |
| 643 | *std::launder(reinterpret_cast<TempEntry*>(working_buffer_.data())); |
David Rogers | f0a3544 | 2020-02-04 12:16:38 -0800 | [diff] [blame] | 644 | |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 645 | DBG("Relocating entry at %zx for key %#010" PRIx32, |
| 646 | size_t(address), |
Wyatt Hepler | ce7b8df | 2020-02-21 10:38:39 -0800 | [diff] [blame] | 647 | key_descriptor.hash()); |
David Rogers | df025cd | 2020-02-06 17:05:34 -0800 | [diff] [blame] | 648 | |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 649 | // Read the entry to be relocated. Store the entry in a local variable and |
David Rogers | f0a3544 | 2020-02-04 12:16:38 -0800 | [diff] [blame] | 650 | // store the key and value in the TempEntry stored in the static allocated |
| 651 | // working_buffer_. |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 652 | Entry entry; |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 653 | TRY(Entry::Read(partition_, key_descriptor.address(), &entry)); |
Wyatt Hepler | ce7b8df | 2020-02-21 10:38:39 -0800 | [diff] [blame] | 654 | |
| 655 | TRY_ASSIGN(size_t key_length, entry.ReadKey(key_buffer)); |
| 656 | string_view key = string_view(key_buffer.data(), key_length); |
| 657 | |
| 658 | StatusWithSize result = entry.ReadValue(value_buffer); |
| 659 | if (!result.ok()) { |
David Rogers | f0a3544 | 2020-02-04 12:16:38 -0800 | [diff] [blame] | 660 | return Status::INTERNAL; |
| 661 | } |
| 662 | |
Wyatt Hepler | ce7b8df | 2020-02-21 10:38:39 -0800 | [diff] [blame] | 663 | const span value = span(value_buffer.data(), result.size()); |
| 664 | TRY(entry.VerifyChecksum(entry_header_format_.checksum, key, value)); |
David Rogers | f0a3544 | 2020-02-04 12:16:38 -0800 | [diff] [blame] | 665 | |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 666 | // Find a new sector for the entry and write it to the new location. For |
| 667 | // relocation the find should not not be a sector already containing the key |
| 668 | // but can be the always empty sector, since this is part of the GC process |
| 669 | // that will result in a new empty sector. Also find a sector that does not |
| 670 | // have reclaimable space (mostly for the full GC, where that would result in |
| 671 | // an immediate extra relocation). |
David Rogers | 8ce55cd | 2020-02-04 19:41:48 -0800 | [diff] [blame] | 672 | SectorDescriptor* new_sector; |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 673 | |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 674 | // Build a vector of sectors to avoid. |
| 675 | Vector<SectorDescriptor*, internal::kEntryRedundancy> old_sectors; |
| 676 | for (auto& address : key_descriptor.addresses()) { |
| 677 | old_sectors.push_back(SectorFromAddress(address)); |
| 678 | } |
| 679 | |
| 680 | // TODO: Remove this once const span can take a non-const span. |
| 681 | auto old_sectors_const = |
| 682 | span(const_cast<const SectorDescriptor**>(old_sectors.data()), |
| 683 | old_sectors.size()); |
| 684 | |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 685 | TRY(FindSectorWithSpace( |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 686 | &new_sector, entry.size(), kGarbageCollect, old_sectors_const)); |
| 687 | |
| 688 | // TODO: This does an entry with new transaction ID. This needs to get changed |
| 689 | // to be a copy of this entry with the same transaction ID. |
Wyatt Hepler | ce7b8df | 2020-02-21 10:38:39 -0800 | [diff] [blame] | 690 | TRY(AppendEntry( |
| 691 | new_sector, &key_descriptor, key, value, key_descriptor.state())); |
David Rogers | df025cd | 2020-02-06 17:05:34 -0800 | [diff] [blame] | 692 | |
Wyatt Hepler | d229828 | 2020-02-20 17:12:45 -0800 | [diff] [blame] | 693 | // Do the valid bytes accounting for the sector the entry was relocated from. |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 694 | // TODO: AppendEntry() creates an entry with new transaction ID. While that is |
| 695 | // used all the old sectors need the valid bytes to be removed. Once it is |
| 696 | // switched over to do a copy of the current entry with the same transaction |
| 697 | // ID, then the valid bytes need to be removed from only the one sector being |
| 698 | // relocated out of. |
| 699 | // SectorFromAddress(address)->RemoveValidBytes(entry.size()); |
| 700 | (void)address; |
| 701 | for (auto& old_sector : old_sectors) { |
| 702 | old_sector->RemoveValidBytes(entry.size()); |
| 703 | } |
David Rogers | df025cd | 2020-02-06 17:05:34 -0800 | [diff] [blame] | 704 | |
| 705 | return Status::OK; |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 706 | } |
| 707 | |
David Rogers | 8db5a72 | 2020-02-03 18:28:34 -0800 | [diff] [blame] | 708 | // Find either an existing sector with enough space that is not the sector to |
| 709 | // skip, or an empty sector. Maintains the invariant that there is always at |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 710 | // least 1 empty sector except during GC. On GC, skip sectors that have |
| 711 | // reclaimable bytes. |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 712 | Status KeyValueStore::FindSectorWithSpace( |
| 713 | SectorDescriptor** found_sector, |
| 714 | size_t size, |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 715 | FindSectorMode find_mode, |
| 716 | span<const SectorDescriptor*> sectors_to_skip) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 717 | SectorDescriptor* first_empty_sector = nullptr; |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 718 | bool at_least_two_empty_sectors = (find_mode == kGarbageCollect); |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 719 | |
| 720 | DBG("Find sector with %zu bytes available, starting with sector %u", |
| 721 | size, |
| 722 | SectorIndex(last_new_sector_)); |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 723 | for (auto& skip_sector : sectors_to_skip) { |
| 724 | DBG(" Skip sector %u", SectorIndex(skip_sector)); |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 725 | } |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 726 | |
David Rogers | 8ce55cd | 2020-02-04 19:41:48 -0800 | [diff] [blame] | 727 | // The last_new_sector_ is the sector that was last selected as the "new empty |
| 728 | // sector" to write to. This last new sector is used as the starting point for |
| 729 | // the next "find a new empty sector to write to" operation. By using the last |
| 730 | // new sector as the start point we will cycle which empty sector is selected |
| 731 | // next, spreading the wear across all the empty sectors and get a wear |
| 732 | // leveling benefit, rather than putting more wear on the lower number |
| 733 | // sectors. |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 734 | SectorDescriptor* sector = last_new_sector_; |
David Rogers | 67f4b6c | 2020-02-06 16:17:09 -0800 | [diff] [blame] | 735 | |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 736 | // Look for a sector to use with enough space. The search uses a 2 priority |
| 737 | // tier process. |
| 738 | // |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 739 | // Tier 1 is sector that already has valid data. During GC only select a |
| 740 | // sector that has no reclaimable bytes. Immediately use the first matching |
| 741 | // sector that is found. |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 742 | // |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 743 | // Tier 2 is find sectors that are empty/erased. While scanning for a partial |
| 744 | // sector, keep track of the first empty sector and if a second empty sector |
| 745 | // was seen. If during GC then count the second empty sector as always seen. |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 746 | for (size_t j = 0; j < sectors_.size(); j++) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 747 | sector += 1; |
| 748 | if (sector == sectors_.end()) { |
| 749 | sector = sectors_.begin(); |
| 750 | } |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 751 | |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 752 | if (std::find(sectors_to_skip.begin(), sectors_to_skip.end(), sector) != |
| 753 | sectors_to_skip.end()) { |
David Rogers | 8db5a72 | 2020-02-03 18:28:34 -0800 | [diff] [blame] | 754 | continue; |
| 755 | } |
| 756 | |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 757 | const size_t sector_size_bytes = partition_.sector_size_bytes(); |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 758 | if (!sector->Empty(sector_size_bytes) && sector->HasSpace(size) && |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 759 | ((find_mode == kAppendEntry) || |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 760 | (sector->RecoverableBytes(sector_size_bytes) == 0))) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 761 | *found_sector = sector; |
David Rogers | 8ce55cd | 2020-02-04 19:41:48 -0800 | [diff] [blame] | 762 | return Status::OK; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 763 | } |
| 764 | |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 765 | if (sector->Empty(sector_size_bytes)) { |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 766 | if (first_empty_sector == nullptr) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 767 | first_empty_sector = sector; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 768 | } else { |
| 769 | at_least_two_empty_sectors = true; |
Wyatt Hepler | 2ad6067 | 2020-01-21 08:00:16 -0800 | [diff] [blame] | 770 | } |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 771 | } |
| 772 | } |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 773 | |
David Rogers | 8ce55cd | 2020-02-04 19:41:48 -0800 | [diff] [blame] | 774 | // If the scan for a partial sector does not find a suitable sector, use the |
| 775 | // first empty sector that was found. Normally it is required to keep 1 empty |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 776 | // sector after the sector found here, but that rule does not apply during GC. |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 777 | if (at_least_two_empty_sectors) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 778 | DBG(" Found a usable empty sector; returning the first found (%u)", |
David Rogers | 8ce55cd | 2020-02-04 19:41:48 -0800 | [diff] [blame] | 779 | SectorIndex(first_empty_sector)); |
| 780 | last_new_sector_ = first_empty_sector; |
| 781 | *found_sector = first_empty_sector; |
| 782 | return Status::OK; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 783 | } |
David Rogers | 8ce55cd | 2020-02-04 19:41:48 -0800 | [diff] [blame] | 784 | |
| 785 | // No sector was found. |
David Rogers | 67f4b6c | 2020-02-06 16:17:09 -0800 | [diff] [blame] | 786 | DBG(" Unable to find a usable sector"); |
David Rogers | 8ce55cd | 2020-02-04 19:41:48 -0800 | [diff] [blame] | 787 | *found_sector = nullptr; |
| 788 | return Status::RESOURCE_EXHAUSTED; |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 789 | } |
| 790 | |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 791 | Status KeyValueStore::FindOrRecoverSectorWithSpace(SectorDescriptor** sector, |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 792 | size_t size) { |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 793 | Status result = FindSectorWithSpace(sector, size, kAppendEntry); |
David Rogers | 890acb5 | 2020-02-28 09:06:50 -0800 | [diff] [blame] | 794 | if (result == Status::RESOURCE_EXHAUSTED && |
| 795 | options_.gc_on_write != GargbageCollectOnWrite::kDisabled) { |
David Rogers | 1541d61 | 2020-02-06 23:47:02 -0800 | [diff] [blame] | 796 | // Garbage collect and then try again to find the best sector. |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 797 | TRY(GarbageCollectPartial()); |
David Rogers | c8fe1f5 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 798 | return FindSectorWithSpace(sector, size, kAppendEntry); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 799 | } |
David Rogers | 8ce55cd | 2020-02-04 19:41:48 -0800 | [diff] [blame] | 800 | return result; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 801 | } |
| 802 | |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 803 | KeyValueStore::SectorDescriptor* KeyValueStore::FindSectorToGarbageCollect() { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 804 | const size_t sector_size_bytes = partition_.sector_size_bytes(); |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 805 | SectorDescriptor* sector_candidate = nullptr; |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 806 | size_t candidate_bytes = 0; |
| 807 | |
| 808 | // Step 1: Try to find a sectors with stale keys and no valid keys (no |
| 809 | // relocation needed). If any such sectors are found, use the sector with the |
| 810 | // most reclaimable bytes. |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 811 | for (auto& sector : sectors_) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 812 | if ((sector.valid_bytes() == 0) && |
| 813 | (sector.RecoverableBytes(sector_size_bytes) > candidate_bytes)) { |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 814 | sector_candidate = §or; |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 815 | candidate_bytes = sector.RecoverableBytes(sector_size_bytes); |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 816 | } |
| 817 | } |
| 818 | |
| 819 | // Step 2: If step 1 yields no sectors, just find the sector with the most |
| 820 | // reclaimable bytes. |
| 821 | if (sector_candidate == nullptr) { |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 822 | for (auto& sector : sectors_) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 823 | if (sector.RecoverableBytes(sector_size_bytes) > candidate_bytes) { |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 824 | sector_candidate = §or; |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 825 | candidate_bytes = sector.RecoverableBytes(sector_size_bytes); |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 826 | } |
| 827 | } |
| 828 | } |
| 829 | |
David Rogers | 5981f31 | 2020-02-13 13:33:56 -0800 | [diff] [blame] | 830 | if (sector_candidate != nullptr) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 831 | DBG("Found sector %u to Garbage Collect, %zu recoverable bytes", |
David Rogers | 5981f31 | 2020-02-13 13:33:56 -0800 | [diff] [blame] | 832 | SectorIndex(sector_candidate), |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 833 | sector_candidate->RecoverableBytes(sector_size_bytes)); |
David Rogers | 5981f31 | 2020-02-13 13:33:56 -0800 | [diff] [blame] | 834 | } else { |
| 835 | DBG("Unable to find sector to garbage collect!"); |
| 836 | } |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 837 | return sector_candidate; |
| 838 | } |
| 839 | |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 840 | Status KeyValueStore::GarbageCollectFull() { |
| 841 | DBG("Garbage Collect all sectors"); |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 842 | SectorDescriptor* sector = last_new_sector_; |
| 843 | |
| 844 | // TODO: look in to making an iterator method for cycling through sectors |
| 845 | // starting from last_new_sector_. |
| 846 | for (size_t j = 0; j < sectors_.size(); j++) { |
| 847 | sector += 1; |
| 848 | if (sector == sectors_.end()) { |
| 849 | sector = sectors_.begin(); |
| 850 | } |
| 851 | |
| 852 | if (sector->RecoverableBytes(partition_.sector_size_bytes()) > 0) { |
| 853 | TRY(GarbageCollectSector(sector)); |
| 854 | } |
| 855 | } |
| 856 | |
| 857 | DBG("Garbage Collect all complete"); |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 858 | return Status::OK; |
| 859 | } |
| 860 | |
| 861 | Status KeyValueStore::GarbageCollectPartial() { |
David Rogers | 67f4b6c | 2020-02-06 16:17:09 -0800 | [diff] [blame] | 862 | DBG("Garbage Collect a single sector"); |
| 863 | |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 864 | // Step 1: Find the sector to garbage collect |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 865 | SectorDescriptor* sector_to_gc = FindSectorToGarbageCollect(); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 866 | |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 867 | if (sector_to_gc == nullptr) { |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 868 | // Nothing to GC, all done. |
| 869 | return Status::OK; |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 870 | } |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 871 | |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 872 | TRY(GarbageCollectSector(sector_to_gc)); |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 873 | return Status::OK; |
| 874 | } |
| 875 | |
| 876 | Status KeyValueStore::GarbageCollectSector(SectorDescriptor* sector_to_gc) { |
| 877 | // Step 1: Move any valid entries in the GC sector to other sectors |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 878 | if (sector_to_gc->valid_bytes() != 0) { |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 879 | for (auto& descriptor : key_descriptors_) { |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 880 | if (AddressInSector(*sector_to_gc, descriptor.address())) { |
David Rogers | 67f4b6c | 2020-02-06 16:17:09 -0800 | [diff] [blame] | 881 | DBG(" Relocate entry"); |
David Rogers | f56131c | 2020-03-04 10:19:22 -0800 | [diff] [blame^] | 882 | TRY(RelocateEntry(descriptor, descriptor.address())); |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 883 | } |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 884 | } |
| 885 | } |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 886 | |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 887 | if (sector_to_gc->valid_bytes() != 0) { |
David Rogers | 67f4b6c | 2020-02-06 16:17:09 -0800 | [diff] [blame] | 888 | ERR(" Failed to relocate valid entries from sector being garbage " |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 889 | "collected, %zu valid bytes remain", |
| 890 | sector_to_gc->valid_bytes()); |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 891 | return Status::INTERNAL; |
| 892 | } |
| 893 | |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 894 | // Step 2: Reinitialize the sector |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 895 | sector_to_gc->set_writable_bytes(0); |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 896 | TRY(partition_.Erase(SectorBaseAddress(sector_to_gc), 1)); |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 897 | sector_to_gc->set_writable_bytes(partition_.sector_size_bytes()); |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 898 | |
David Rogers | cd87c32 | 2020-02-27 14:04:08 -0800 | [diff] [blame] | 899 | DBG(" Garbage Collect sector %u complete", SectorIndex(sector_to_gc)); |
David Rogers | a12786b | 2020-01-31 16:02:33 -0800 | [diff] [blame] | 900 | return Status::OK; |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 901 | } |
| 902 | |
David Rogers | 2761aeb | 2020-01-31 17:09:00 -0800 | [diff] [blame] | 903 | Status KeyValueStore::AppendEntry(SectorDescriptor* sector, |
| 904 | KeyDescriptor* key_descriptor, |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 905 | string_view key, |
Wyatt Hepler | 5a33d8c | 2020-02-06 09:32:58 -0800 | [diff] [blame] | 906 | span<const byte> value, |
| 907 | KeyDescriptor::State new_state) { |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 908 | const Address address = NextWritableAddress(sector); |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 909 | Entry entry = CreateEntry(address, key, value, new_state); |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 910 | |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 911 | DBG("Appending %zu B entry with transaction ID %" PRIu32 " to address %#zx", |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 912 | entry.size(), |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 913 | entry.transaction_id(), |
| 914 | size_t(address)); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 915 | |
David Rogers | 6592d29 | 2020-02-14 14:19:26 -0800 | [diff] [blame] | 916 | StatusWithSize result = entry.Write(key, value); |
| 917 | // Remove any bytes that were written, even if the write was not successful. |
Keir Mierle | 0a52aed | 2020-02-21 09:24:36 -0800 | [diff] [blame] | 918 | // This is important to retain the writable space invariant on the sectors. |
David Rogers | 6592d29 | 2020-02-14 14:19:26 -0800 | [diff] [blame] | 919 | sector->RemoveWritableBytes(result.size()); |
| 920 | |
| 921 | if (!result.ok()) { |
Keir Mierle | 0a52aed | 2020-02-21 09:24:36 -0800 | [diff] [blame] | 922 | ERR("Failed to write %zu bytes at %" PRIx32 ". %zu actually written", |
David Rogers | 6592d29 | 2020-02-14 14:19:26 -0800 | [diff] [blame] | 923 | entry.size(), |
Keir Mierle | 0a52aed | 2020-02-21 09:24:36 -0800 | [diff] [blame] | 924 | address, |
David Rogers | 6592d29 | 2020-02-14 14:19:26 -0800 | [diff] [blame] | 925 | result.size()); |
| 926 | return result.status(); |
| 927 | } |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 928 | |
| 929 | if (options_.verify_on_write) { |
Wyatt Hepler | e541e07 | 2020-02-14 09:10:53 -0800 | [diff] [blame] | 930 | TRY(entry.VerifyChecksumInFlash(entry_header_format_.checksum)); |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 931 | } |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 932 | |
Keir Mierle | 9e38b40 | 2020-02-21 13:06:21 -0800 | [diff] [blame] | 933 | // Entry was written successfully; update the key descriptor and the sector |
| 934 | // descriptor to reflect the new entry. |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 935 | entry.UpdateDescriptor(key_descriptor); |
David Rogers | 6592d29 | 2020-02-14 14:19:26 -0800 | [diff] [blame] | 936 | sector->AddValidBytes(result.size()); |
Wyatt Hepler | 4da1fcb | 2020-01-30 17:32:18 -0800 | [diff] [blame] | 937 | return Status::OK; |
Wyatt Hepler | b760954 | 2020-01-24 10:29:54 -0800 | [diff] [blame] | 938 | } |
| 939 | |
Wyatt Hepler | bdd8e5a | 2020-02-20 19:27:26 -0800 | [diff] [blame] | 940 | KeyValueStore::Entry KeyValueStore::CreateEntry(Address address, |
| 941 | std::string_view key, |
| 942 | span<const byte> value, |
| 943 | KeyDescriptor::State state) { |
Keir Mierle | 9e38b40 | 2020-02-21 13:06:21 -0800 | [diff] [blame] | 944 | // Always bump the transaction ID when creating a new entry. |
| 945 | // |
| 946 | // Burning transaction IDs prevents inconsistencies between flash and memory |
| 947 | // that which could happen if a write succeeds, but for some reason the read |
| 948 | // and verify step fails. Here's how this would happen: |
| 949 | // |
| 950 | // 1. The entry is written but for some reason the flash reports failure OR |
| 951 | // The write succeeds, but the read / verify operation fails. |
| 952 | // 2. The transaction ID is NOT incremented, because of the failure |
| 953 | // 3. (later) A new entry is written, re-using the transaction ID (oops) |
| 954 | // |
| 955 | // By always burning transaction IDs, the above problem can't happen. |
| 956 | last_transaction_id_ += 1; |
| 957 | |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 958 | if (state == KeyDescriptor::kDeleted) { |
Wyatt Hepler | 7465be3 | 2020-02-21 15:30:53 -0800 | [diff] [blame] | 959 | return Entry::Tombstone( |
| 960 | partition_, address, entry_header_format_, key, last_transaction_id_); |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 961 | } |
| 962 | return Entry::Valid(partition_, |
| 963 | address, |
Wyatt Hepler | 88adfe8 | 2020-02-20 19:33:27 -0800 | [diff] [blame] | 964 | entry_header_format_, |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 965 | key, |
| 966 | value, |
Keir Mierle | 9e38b40 | 2020-02-21 13:06:21 -0800 | [diff] [blame] | 967 | last_transaction_id_); |
Wyatt Hepler | d229828 | 2020-02-20 17:12:45 -0800 | [diff] [blame] | 968 | } |
| 969 | |
| 970 | void KeyValueStore::Reset() { |
| 971 | initialized_ = false; |
| 972 | key_descriptors_.clear(); |
| 973 | last_new_sector_ = nullptr; |
| 974 | last_transaction_id_ = 0; |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 975 | } |
| 976 | |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 977 | void KeyValueStore::LogDebugInfo() { |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 978 | const size_t sector_size_bytes = partition_.sector_size_bytes(); |
| 979 | DBG("====================== KEY VALUE STORE DUMP ========================="); |
| 980 | DBG(" "); |
| 981 | DBG("Flash partition:"); |
Wyatt Hepler | ad0a793 | 2020-02-06 08:20:38 -0800 | [diff] [blame] | 982 | DBG(" Sector count = %zu", partition_.sector_count()); |
Wyatt Hepler | 38ce30f | 2020-02-19 11:48:31 -0800 | [diff] [blame] | 983 | DBG(" Sector max count = %zu", sectors_.max_size()); |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 984 | DBG(" Sectors in use = %zu", sectors_.size()); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 985 | DBG(" Sector size = %zu", sector_size_bytes); |
| 986 | DBG(" Total size = %zu", partition_.size_bytes()); |
| 987 | DBG(" Alignment = %zu", partition_.alignment_bytes()); |
| 988 | DBG(" "); |
| 989 | DBG("Key descriptors:"); |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 990 | DBG(" Entry count = %zu", key_descriptors_.size()); |
Wyatt Hepler | 38ce30f | 2020-02-19 11:48:31 -0800 | [diff] [blame] | 991 | DBG(" Max entry count = %zu", key_descriptors_.max_size()); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 992 | DBG(" "); |
| 993 | DBG(" # hash version address address (hex)"); |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 994 | for (size_t i = 0; i < key_descriptors_.size(); ++i) { |
| 995 | const KeyDescriptor& kd = key_descriptors_[i]; |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 996 | DBG(" |%3zu: | %8zx |%8zu | %8zu | %8zx", |
| 997 | i, |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 998 | size_t(kd.hash()), |
| 999 | size_t(kd.transaction_id()), |
| 1000 | size_t(kd.address()), |
| 1001 | size_t(kd.address())); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 1002 | } |
| 1003 | DBG(" "); |
| 1004 | |
| 1005 | DBG("Sector descriptors:"); |
| 1006 | DBG(" # tail free valid has_space"); |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 1007 | for (size_t sector_id = 0; sector_id < sectors_.size(); ++sector_id) { |
| 1008 | const SectorDescriptor& sd = sectors_[sector_id]; |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 1009 | DBG(" |%3zu: | %8zu |%8zu | %s", |
| 1010 | sector_id, |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 1011 | size_t(sd.writable_bytes()), |
| 1012 | sd.valid_bytes(), |
| 1013 | sd.writable_bytes() ? "YES" : ""); |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 1014 | } |
| 1015 | DBG(" "); |
| 1016 | |
| 1017 | // TODO: This should stop logging after some threshold. |
| 1018 | // size_t dumped_bytes = 0; |
| 1019 | DBG("Sector raw data:"); |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 1020 | for (size_t sector_id = 0; sector_id < sectors_.size(); ++sector_id) { |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 1021 | // Read sector data. Yes, this will blow the stack on embedded. |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 1022 | std::array<byte, 500> raw_sector_data; // TODO!!! |
Keir Mierle | 8c352dc | 2020-02-02 13:58:19 -0800 | [diff] [blame] | 1023 | StatusWithSize sws = |
| 1024 | partition_.Read(sector_id * sector_size_bytes, raw_sector_data); |
| 1025 | DBG("Read: %zu bytes", sws.size()); |
| 1026 | |
| 1027 | DBG(" base addr offs 0 1 2 3 4 5 6 7"); |
| 1028 | for (size_t i = 0; i < sector_size_bytes; i += 8) { |
| 1029 | DBG(" %3zu %8zx %5zu | %02x %02x %02x %02x %02x %02x %02x %02x", |
| 1030 | sector_id, |
| 1031 | (sector_id * sector_size_bytes) + i, |
| 1032 | i, |
| 1033 | static_cast<unsigned int>(raw_sector_data[i + 0]), |
| 1034 | static_cast<unsigned int>(raw_sector_data[i + 1]), |
| 1035 | static_cast<unsigned int>(raw_sector_data[i + 2]), |
| 1036 | static_cast<unsigned int>(raw_sector_data[i + 3]), |
| 1037 | static_cast<unsigned int>(raw_sector_data[i + 4]), |
| 1038 | static_cast<unsigned int>(raw_sector_data[i + 5]), |
| 1039 | static_cast<unsigned int>(raw_sector_data[i + 6]), |
| 1040 | static_cast<unsigned int>(raw_sector_data[i + 7])); |
| 1041 | |
| 1042 | // TODO: Fix exit condition. |
| 1043 | if (i > 128) { |
| 1044 | break; |
| 1045 | } |
| 1046 | } |
| 1047 | DBG(" "); |
| 1048 | } |
| 1049 | |
| 1050 | DBG("////////////////////// KEY VALUE STORE DUMP END /////////////////////"); |
| 1051 | } |
| 1052 | |
David Rogers | cf680ab | 2020-02-12 23:28:32 -0800 | [diff] [blame] | 1053 | void KeyValueStore::LogSectors() const { |
| 1054 | DBG("Sector descriptors: count %zu", sectors_.size()); |
Wyatt Hepler | 1c329ca | 2020-02-07 18:07:23 -0800 | [diff] [blame] | 1055 | for (auto& sector : sectors_) { |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 1056 | DBG(" - Sector %u: valid %zu, recoverable %zu, free %zu", |
David Rogers | 50185ad | 2020-02-07 00:02:46 -0800 | [diff] [blame] | 1057 | SectorIndex(§or), |
Wyatt Hepler | 2c7eca0 | 2020-02-18 16:01:42 -0800 | [diff] [blame] | 1058 | sector.valid_bytes(), |
| 1059 | sector.RecoverableBytes(partition_.sector_size_bytes()), |
| 1060 | sector.writable_bytes()); |
David Rogers | 50185ad | 2020-02-07 00:02:46 -0800 | [diff] [blame] | 1061 | } |
| 1062 | } |
| 1063 | |
David Rogers | cf680ab | 2020-02-12 23:28:32 -0800 | [diff] [blame] | 1064 | void KeyValueStore::LogKeyDescriptor() const { |
| 1065 | DBG("Key descriptors: count %zu", key_descriptors_.size()); |
| 1066 | for (auto& key : key_descriptors_) { |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 1067 | DBG(" - Key: %s, hash %#zx, transaction ID %zu, address %#zx", |
David Rogers | cf680ab | 2020-02-12 23:28:32 -0800 | [diff] [blame] | 1068 | key.deleted() ? "Deleted" : "Valid", |
Wyatt Hepler | 1fc1104 | 2020-02-19 17:17:51 -0800 | [diff] [blame] | 1069 | static_cast<size_t>(key.hash()), |
| 1070 | static_cast<size_t>(key.transaction_id()), |
| 1071 | static_cast<size_t>(key.address())); |
David Rogers | cf680ab | 2020-02-12 23:28:32 -0800 | [diff] [blame] | 1072 | } |
| 1073 | } |
| 1074 | |
Wyatt Hepler | 2ad6067 | 2020-01-21 08:00:16 -0800 | [diff] [blame] | 1075 | } // namespace pw::kvs |