Benoît Canet | 27cec15 | 2014-02-21 22:21:10 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Quorum Block filter |
| 3 | * |
| 4 | * Copyright (C) 2012-2014 Nodalink, EURL. |
| 5 | * |
| 6 | * Author: |
| 7 | * Benoît Canet <benoit.canet@irqsave.net> |
| 8 | * |
| 9 | * Based on the design and code of blkverify.c (Copyright (C) 2010 IBM, Corp) |
| 10 | * and blkmirror.c (Copyright (C) 2011 Red Hat, Inc). |
| 11 | * |
| 12 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| 13 | * See the COPYING file in the top-level directory. |
| 14 | */ |
| 15 | |
| 16 | #include "block/block_int.h" |
Max Reitz | fafcfe2 | 2014-07-18 20:25:00 +0200 | [diff] [blame] | 17 | #include "qapi/qmp/qbool.h" |
| 18 | #include "qapi/qmp/qdict.h" |
Markus Armbruster | cc7a8ea | 2015-03-17 17:22:46 +0100 | [diff] [blame] | 19 | #include "qapi/qmp/qerror.h" |
Max Reitz | fafcfe2 | 2014-07-18 20:25:00 +0200 | [diff] [blame] | 20 | #include "qapi/qmp/qint.h" |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 21 | #include "qapi/qmp/qjson.h" |
Max Reitz | fafcfe2 | 2014-07-18 20:25:00 +0200 | [diff] [blame] | 22 | #include "qapi/qmp/qlist.h" |
| 23 | #include "qapi/qmp/qstring.h" |
Wenchao Xia | fe069d9 | 2014-06-18 08:43:53 +0200 | [diff] [blame] | 24 | #include "qapi-event.h" |
Daniel P. Berrange | 488981a4 | 2015-07-01 18:10:35 +0100 | [diff] [blame] | 25 | #include "crypto/hash.h" |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 26 | |
| 27 | #define HASH_LENGTH 32 |
| 28 | |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 29 | #define QUORUM_OPT_VOTE_THRESHOLD "vote-threshold" |
| 30 | #define QUORUM_OPT_BLKVERIFY "blkverify" |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 31 | #define QUORUM_OPT_REWRITE "rewrite-corrupted" |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 32 | #define QUORUM_OPT_READ_PATTERN "read-pattern" |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 33 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 34 | /* This union holds a vote hash value */ |
| 35 | typedef union QuorumVoteValue { |
Daniel P. Berrange | 488981a4 | 2015-07-01 18:10:35 +0100 | [diff] [blame] | 36 | uint8_t h[HASH_LENGTH]; /* SHA-256 hash */ |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 37 | int64_t l; /* simpler 64 bits hash */ |
| 38 | } QuorumVoteValue; |
| 39 | |
| 40 | /* A vote item */ |
| 41 | typedef struct QuorumVoteItem { |
| 42 | int index; |
| 43 | QLIST_ENTRY(QuorumVoteItem) next; |
| 44 | } QuorumVoteItem; |
| 45 | |
| 46 | /* this structure is a vote version. A version is the set of votes sharing the |
| 47 | * same vote value. |
| 48 | * The set of votes will be tracked with the items field and its cardinality is |
| 49 | * vote_count. |
| 50 | */ |
| 51 | typedef struct QuorumVoteVersion { |
| 52 | QuorumVoteValue value; |
| 53 | int index; |
| 54 | int vote_count; |
| 55 | QLIST_HEAD(, QuorumVoteItem) items; |
| 56 | QLIST_ENTRY(QuorumVoteVersion) next; |
| 57 | } QuorumVoteVersion; |
| 58 | |
| 59 | /* this structure holds a group of vote versions together */ |
| 60 | typedef struct QuorumVotes { |
| 61 | QLIST_HEAD(, QuorumVoteVersion) vote_list; |
| 62 | bool (*compare)(QuorumVoteValue *a, QuorumVoteValue *b); |
| 63 | } QuorumVotes; |
Benoît Canet | 27cec15 | 2014-02-21 22:21:10 +0100 | [diff] [blame] | 64 | |
Benoît Canet | cadebd7 | 2014-02-21 22:21:11 +0100 | [diff] [blame] | 65 | /* the following structure holds the state of one quorum instance */ |
| 66 | typedef struct BDRVQuorumState { |
| 67 | BlockDriverState **bs; /* children BlockDriverStates */ |
| 68 | int num_children; /* children count */ |
| 69 | int threshold; /* if less than threshold children reads gave the |
| 70 | * same result a quorum error occurs. |
| 71 | */ |
| 72 | bool is_blkverify; /* true if the driver is in blkverify mode |
| 73 | * Writes are mirrored on two children devices. |
| 74 | * On reads the two children devices' contents are |
| 75 | * compared and if a difference is spotted its |
| 76 | * location is printed and the code aborts. |
| 77 | * It is useful to debug other block drivers by |
| 78 | * comparing them with a reference one. |
| 79 | */ |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 80 | bool rewrite_corrupted;/* true if the driver must rewrite-on-read corrupted |
| 81 | * block if Quorum is reached. |
| 82 | */ |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 83 | |
| 84 | QuorumReadPattern read_pattern; |
Benoît Canet | cadebd7 | 2014-02-21 22:21:11 +0100 | [diff] [blame] | 85 | } BDRVQuorumState; |
| 86 | |
Benoît Canet | 27cec15 | 2014-02-21 22:21:10 +0100 | [diff] [blame] | 87 | typedef struct QuorumAIOCB QuorumAIOCB; |
| 88 | |
| 89 | /* Quorum will create one instance of the following structure per operation it |
| 90 | * performs on its children. |
| 91 | * So for each read/write operation coming from the upper layer there will be |
| 92 | * $children_count QuorumChildRequest. |
| 93 | */ |
| 94 | typedef struct QuorumChildRequest { |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 95 | BlockAIOCB *aiocb; |
Benoît Canet | 27cec15 | 2014-02-21 22:21:10 +0100 | [diff] [blame] | 96 | QEMUIOVector qiov; |
| 97 | uint8_t *buf; |
| 98 | int ret; |
| 99 | QuorumAIOCB *parent; |
| 100 | } QuorumChildRequest; |
| 101 | |
| 102 | /* Quorum will use the following structure to track progress of each read/write |
| 103 | * operation received by the upper layer. |
| 104 | * This structure hold pointers to the QuorumChildRequest structures instances |
| 105 | * used to do operations on each children and track overall progress. |
| 106 | */ |
| 107 | struct QuorumAIOCB { |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 108 | BlockAIOCB common; |
Benoît Canet | 27cec15 | 2014-02-21 22:21:10 +0100 | [diff] [blame] | 109 | |
| 110 | /* Request metadata */ |
| 111 | uint64_t sector_num; |
| 112 | int nb_sectors; |
| 113 | |
| 114 | QEMUIOVector *qiov; /* calling IOV */ |
| 115 | |
| 116 | QuorumChildRequest *qcrs; /* individual child requests */ |
| 117 | int count; /* number of completed AIOCB */ |
| 118 | int success_count; /* number of successfully completed AIOCB */ |
| 119 | |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 120 | int rewrite_count; /* number of replica to rewrite: count down to |
| 121 | * zero once writes are fired |
| 122 | */ |
| 123 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 124 | QuorumVotes votes; |
| 125 | |
Benoît Canet | 27cec15 | 2014-02-21 22:21:10 +0100 | [diff] [blame] | 126 | bool is_read; |
| 127 | int vote_ret; |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 128 | int child_iter; /* which child to read in fifo pattern */ |
Benoît Canet | 27cec15 | 2014-02-21 22:21:10 +0100 | [diff] [blame] | 129 | }; |
Benoît Canet | cadebd7 | 2014-02-21 22:21:11 +0100 | [diff] [blame] | 130 | |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 131 | static bool quorum_vote(QuorumAIOCB *acb); |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 132 | |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 133 | static void quorum_aio_cancel(BlockAIOCB *blockacb) |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 134 | { |
| 135 | QuorumAIOCB *acb = container_of(blockacb, QuorumAIOCB, common); |
| 136 | BDRVQuorumState *s = acb->common.bs->opaque; |
| 137 | int i; |
| 138 | |
| 139 | /* cancel all callbacks */ |
| 140 | for (i = 0; i < s->num_children; i++) { |
Liu Yuan | 997dd8d | 2014-09-11 13:41:21 +0800 | [diff] [blame] | 141 | if (acb->qcrs[i].aiocb) { |
Fam Zheng | 7940e50 | 2014-09-11 13:41:22 +0800 | [diff] [blame] | 142 | bdrv_aio_cancel_async(acb->qcrs[i].aiocb); |
Liu Yuan | 997dd8d | 2014-09-11 13:41:21 +0800 | [diff] [blame] | 143 | } |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 144 | } |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 145 | } |
| 146 | |
| 147 | static AIOCBInfo quorum_aiocb_info = { |
| 148 | .aiocb_size = sizeof(QuorumAIOCB), |
Fam Zheng | 7940e50 | 2014-09-11 13:41:22 +0800 | [diff] [blame] | 149 | .cancel_async = quorum_aio_cancel, |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 150 | }; |
| 151 | |
| 152 | static void quorum_aio_finalize(QuorumAIOCB *acb) |
| 153 | { |
Benoît Canet | 7db6982 | 2014-02-21 22:21:14 +0100 | [diff] [blame] | 154 | int i, ret = 0; |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 155 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 156 | if (acb->vote_ret) { |
| 157 | ret = acb->vote_ret; |
| 158 | } |
| 159 | |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 160 | acb->common.cb(acb->common.opaque, ret); |
| 161 | |
Benoît Canet | 7db6982 | 2014-02-21 22:21:14 +0100 | [diff] [blame] | 162 | if (acb->is_read) { |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 163 | /* on the quorum case acb->child_iter == s->num_children - 1 */ |
| 164 | for (i = 0; i <= acb->child_iter; i++) { |
Benoît Canet | 7db6982 | 2014-02-21 22:21:14 +0100 | [diff] [blame] | 165 | qemu_vfree(acb->qcrs[i].buf); |
| 166 | qemu_iovec_destroy(&acb->qcrs[i].qiov); |
| 167 | } |
| 168 | } |
| 169 | |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 170 | g_free(acb->qcrs); |
Fam Zheng | 8007429 | 2014-09-11 13:41:28 +0800 | [diff] [blame] | 171 | qemu_aio_unref(acb); |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 172 | } |
| 173 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 174 | static bool quorum_sha256_compare(QuorumVoteValue *a, QuorumVoteValue *b) |
| 175 | { |
| 176 | return !memcmp(a->h, b->h, HASH_LENGTH); |
| 177 | } |
| 178 | |
| 179 | static bool quorum_64bits_compare(QuorumVoteValue *a, QuorumVoteValue *b) |
| 180 | { |
| 181 | return a->l == b->l; |
| 182 | } |
| 183 | |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 184 | static QuorumAIOCB *quorum_aio_get(BDRVQuorumState *s, |
| 185 | BlockDriverState *bs, |
| 186 | QEMUIOVector *qiov, |
| 187 | uint64_t sector_num, |
| 188 | int nb_sectors, |
Markus Armbruster | 097310b | 2014-10-07 13:59:15 +0200 | [diff] [blame] | 189 | BlockCompletionFunc *cb, |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 190 | void *opaque) |
| 191 | { |
| 192 | QuorumAIOCB *acb = qemu_aio_get(&quorum_aiocb_info, bs, cb, opaque); |
| 193 | int i; |
| 194 | |
| 195 | acb->common.bs->opaque = s; |
| 196 | acb->sector_num = sector_num; |
| 197 | acb->nb_sectors = nb_sectors; |
| 198 | acb->qiov = qiov; |
| 199 | acb->qcrs = g_new0(QuorumChildRequest, s->num_children); |
| 200 | acb->count = 0; |
| 201 | acb->success_count = 0; |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 202 | acb->rewrite_count = 0; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 203 | acb->votes.compare = quorum_sha256_compare; |
| 204 | QLIST_INIT(&acb->votes.vote_list); |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 205 | acb->is_read = false; |
| 206 | acb->vote_ret = 0; |
| 207 | |
| 208 | for (i = 0; i < s->num_children; i++) { |
| 209 | acb->qcrs[i].buf = NULL; |
| 210 | acb->qcrs[i].ret = 0; |
| 211 | acb->qcrs[i].parent = acb; |
| 212 | } |
| 213 | |
| 214 | return acb; |
| 215 | } |
| 216 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 217 | static void quorum_report_bad(QuorumAIOCB *acb, char *node_name, int ret) |
| 218 | { |
Wenchao Xia | fe069d9 | 2014-06-18 08:43:53 +0200 | [diff] [blame] | 219 | const char *msg = NULL; |
Benoît Canet | 0c76273 | 2014-02-22 18:43:41 +0100 | [diff] [blame] | 220 | if (ret < 0) { |
Wenchao Xia | fe069d9 | 2014-06-18 08:43:53 +0200 | [diff] [blame] | 221 | msg = strerror(-ret); |
Benoît Canet | 0c76273 | 2014-02-22 18:43:41 +0100 | [diff] [blame] | 222 | } |
Wenchao Xia | fe069d9 | 2014-06-18 08:43:53 +0200 | [diff] [blame] | 223 | qapi_event_send_quorum_report_bad(!!msg, msg, node_name, |
| 224 | acb->sector_num, acb->nb_sectors, &error_abort); |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 225 | } |
| 226 | |
| 227 | static void quorum_report_failure(QuorumAIOCB *acb) |
| 228 | { |
Alberto Garcia | 9b2aa84 | 2015-04-08 12:29:18 +0300 | [diff] [blame] | 229 | const char *reference = bdrv_get_device_or_node_name(acb->common.bs); |
Wenchao Xia | fe069d9 | 2014-06-18 08:43:53 +0200 | [diff] [blame] | 230 | qapi_event_send_quorum_failure(reference, acb->sector_num, |
| 231 | acb->nb_sectors, &error_abort); |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 232 | } |
| 233 | |
| 234 | static int quorum_vote_error(QuorumAIOCB *acb); |
| 235 | |
| 236 | static bool quorum_has_too_much_io_failed(QuorumAIOCB *acb) |
| 237 | { |
| 238 | BDRVQuorumState *s = acb->common.bs->opaque; |
| 239 | |
| 240 | if (acb->success_count < s->threshold) { |
| 241 | acb->vote_ret = quorum_vote_error(acb); |
| 242 | quorum_report_failure(acb); |
| 243 | return true; |
| 244 | } |
| 245 | |
| 246 | return false; |
| 247 | } |
| 248 | |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 249 | static void quorum_rewrite_aio_cb(void *opaque, int ret) |
| 250 | { |
| 251 | QuorumAIOCB *acb = opaque; |
| 252 | |
| 253 | /* one less rewrite to do */ |
| 254 | acb->rewrite_count--; |
| 255 | |
| 256 | /* wait until all rewrite callbacks have completed */ |
| 257 | if (acb->rewrite_count) { |
| 258 | return; |
| 259 | } |
| 260 | |
| 261 | quorum_aio_finalize(acb); |
| 262 | } |
| 263 | |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 264 | static BlockAIOCB *read_fifo_child(QuorumAIOCB *acb); |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 265 | |
| 266 | static void quorum_copy_qiov(QEMUIOVector *dest, QEMUIOVector *source) |
| 267 | { |
| 268 | int i; |
| 269 | assert(dest->niov == source->niov); |
| 270 | assert(dest->size == source->size); |
| 271 | for (i = 0; i < source->niov; i++) { |
| 272 | assert(dest->iov[i].iov_len == source->iov[i].iov_len); |
| 273 | memcpy(dest->iov[i].iov_base, |
| 274 | source->iov[i].iov_base, |
| 275 | source->iov[i].iov_len); |
| 276 | } |
| 277 | } |
| 278 | |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 279 | static void quorum_aio_cb(void *opaque, int ret) |
| 280 | { |
| 281 | QuorumChildRequest *sacb = opaque; |
| 282 | QuorumAIOCB *acb = sacb->parent; |
| 283 | BDRVQuorumState *s = acb->common.bs->opaque; |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 284 | bool rewrite = false; |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 285 | |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 286 | if (acb->is_read && s->read_pattern == QUORUM_READ_PATTERN_FIFO) { |
| 287 | /* We try to read next child in FIFO order if we fail to read */ |
| 288 | if (ret < 0 && ++acb->child_iter < s->num_children) { |
| 289 | read_fifo_child(acb); |
| 290 | return; |
| 291 | } |
| 292 | |
| 293 | if (ret == 0) { |
| 294 | quorum_copy_qiov(acb->qiov, &acb->qcrs[acb->child_iter].qiov); |
| 295 | } |
| 296 | acb->vote_ret = ret; |
| 297 | quorum_aio_finalize(acb); |
| 298 | return; |
| 299 | } |
| 300 | |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 301 | sacb->ret = ret; |
| 302 | acb->count++; |
| 303 | if (ret == 0) { |
| 304 | acb->success_count++; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 305 | } else { |
| 306 | quorum_report_bad(acb, sacb->aiocb->bs->node_name, ret); |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 307 | } |
| 308 | assert(acb->count <= s->num_children); |
| 309 | assert(acb->success_count <= s->num_children); |
| 310 | if (acb->count < s->num_children) { |
| 311 | return; |
| 312 | } |
| 313 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 314 | /* Do the vote on read */ |
| 315 | if (acb->is_read) { |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 316 | rewrite = quorum_vote(acb); |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 317 | } else { |
| 318 | quorum_has_too_much_io_failed(acb); |
| 319 | } |
| 320 | |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 321 | /* if no rewrite is done the code will finish right away */ |
| 322 | if (!rewrite) { |
| 323 | quorum_aio_finalize(acb); |
| 324 | } |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 325 | } |
| 326 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 327 | static void quorum_report_bad_versions(BDRVQuorumState *s, |
| 328 | QuorumAIOCB *acb, |
| 329 | QuorumVoteValue *value) |
| 330 | { |
| 331 | QuorumVoteVersion *version; |
| 332 | QuorumVoteItem *item; |
| 333 | |
| 334 | QLIST_FOREACH(version, &acb->votes.vote_list, next) { |
| 335 | if (acb->votes.compare(&version->value, value)) { |
| 336 | continue; |
| 337 | } |
| 338 | QLIST_FOREACH(item, &version->items, next) { |
| 339 | quorum_report_bad(acb, s->bs[item->index]->node_name, 0); |
| 340 | } |
| 341 | } |
| 342 | } |
| 343 | |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 344 | static bool quorum_rewrite_bad_versions(BDRVQuorumState *s, QuorumAIOCB *acb, |
| 345 | QuorumVoteValue *value) |
| 346 | { |
| 347 | QuorumVoteVersion *version; |
| 348 | QuorumVoteItem *item; |
| 349 | int count = 0; |
| 350 | |
| 351 | /* first count the number of bad versions: done first to avoid concurrency |
| 352 | * issues. |
| 353 | */ |
| 354 | QLIST_FOREACH(version, &acb->votes.vote_list, next) { |
| 355 | if (acb->votes.compare(&version->value, value)) { |
| 356 | continue; |
| 357 | } |
| 358 | QLIST_FOREACH(item, &version->items, next) { |
| 359 | count++; |
| 360 | } |
| 361 | } |
| 362 | |
| 363 | /* quorum_rewrite_aio_cb will count down this to zero */ |
| 364 | acb->rewrite_count = count; |
| 365 | |
| 366 | /* now fire the correcting rewrites */ |
| 367 | QLIST_FOREACH(version, &acb->votes.vote_list, next) { |
| 368 | if (acb->votes.compare(&version->value, value)) { |
| 369 | continue; |
| 370 | } |
| 371 | QLIST_FOREACH(item, &version->items, next) { |
| 372 | bdrv_aio_writev(s->bs[item->index], acb->sector_num, acb->qiov, |
| 373 | acb->nb_sectors, quorum_rewrite_aio_cb, acb); |
| 374 | } |
| 375 | } |
| 376 | |
| 377 | /* return true if any rewrite is done else false */ |
| 378 | return count; |
| 379 | } |
| 380 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 381 | static void quorum_count_vote(QuorumVotes *votes, |
| 382 | QuorumVoteValue *value, |
| 383 | int index) |
| 384 | { |
| 385 | QuorumVoteVersion *v = NULL, *version = NULL; |
| 386 | QuorumVoteItem *item; |
| 387 | |
| 388 | /* look if we have something with this hash */ |
| 389 | QLIST_FOREACH(v, &votes->vote_list, next) { |
| 390 | if (votes->compare(&v->value, value)) { |
| 391 | version = v; |
| 392 | break; |
| 393 | } |
| 394 | } |
| 395 | |
| 396 | /* It's a version not yet in the list add it */ |
| 397 | if (!version) { |
| 398 | version = g_new0(QuorumVoteVersion, 1); |
| 399 | QLIST_INIT(&version->items); |
| 400 | memcpy(&version->value, value, sizeof(version->value)); |
| 401 | version->index = index; |
| 402 | version->vote_count = 0; |
| 403 | QLIST_INSERT_HEAD(&votes->vote_list, version, next); |
| 404 | } |
| 405 | |
| 406 | version->vote_count++; |
| 407 | |
| 408 | item = g_new0(QuorumVoteItem, 1); |
| 409 | item->index = index; |
| 410 | QLIST_INSERT_HEAD(&version->items, item, next); |
| 411 | } |
| 412 | |
| 413 | static void quorum_free_vote_list(QuorumVotes *votes) |
| 414 | { |
| 415 | QuorumVoteVersion *version, *next_version; |
| 416 | QuorumVoteItem *item, *next_item; |
| 417 | |
| 418 | QLIST_FOREACH_SAFE(version, &votes->vote_list, next, next_version) { |
| 419 | QLIST_REMOVE(version, next); |
| 420 | QLIST_FOREACH_SAFE(item, &version->items, next, next_item) { |
| 421 | QLIST_REMOVE(item, next); |
| 422 | g_free(item); |
| 423 | } |
| 424 | g_free(version); |
| 425 | } |
| 426 | } |
| 427 | |
| 428 | static int quorum_compute_hash(QuorumAIOCB *acb, int i, QuorumVoteValue *hash) |
| 429 | { |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 430 | QEMUIOVector *qiov = &acb->qcrs[i].qiov; |
Daniel P. Berrange | 488981a4 | 2015-07-01 18:10:35 +0100 | [diff] [blame] | 431 | size_t len = sizeof(hash->h); |
| 432 | uint8_t *data = hash->h; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 433 | |
Daniel P. Berrange | 488981a4 | 2015-07-01 18:10:35 +0100 | [diff] [blame] | 434 | /* XXX - would be nice if we could pass in the Error ** |
| 435 | * and propagate that back, but this quorum code is |
| 436 | * restricted to just errno values currently */ |
| 437 | if (qcrypto_hash_bytesv(QCRYPTO_HASH_ALG_SHA256, |
| 438 | qiov->iov, qiov->niov, |
| 439 | &data, &len, |
| 440 | NULL) < 0) { |
| 441 | return -EINVAL; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 442 | } |
| 443 | |
Daniel P. Berrange | 488981a4 | 2015-07-01 18:10:35 +0100 | [diff] [blame] | 444 | return 0; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 445 | } |
| 446 | |
| 447 | static QuorumVoteVersion *quorum_get_vote_winner(QuorumVotes *votes) |
| 448 | { |
| 449 | int max = 0; |
| 450 | QuorumVoteVersion *candidate, *winner = NULL; |
| 451 | |
| 452 | QLIST_FOREACH(candidate, &votes->vote_list, next) { |
| 453 | if (candidate->vote_count > max) { |
| 454 | max = candidate->vote_count; |
| 455 | winner = candidate; |
| 456 | } |
| 457 | } |
| 458 | |
| 459 | return winner; |
| 460 | } |
| 461 | |
| 462 | /* qemu_iovec_compare is handy for blkverify mode because it returns the first |
| 463 | * differing byte location. Yet it is handcoded to compare vectors one byte |
| 464 | * after another so it does not benefit from the libc SIMD optimizations. |
| 465 | * quorum_iovec_compare is written for speed and should be used in the non |
| 466 | * blkverify mode of quorum. |
| 467 | */ |
| 468 | static bool quorum_iovec_compare(QEMUIOVector *a, QEMUIOVector *b) |
| 469 | { |
| 470 | int i; |
| 471 | int result; |
| 472 | |
| 473 | assert(a->niov == b->niov); |
| 474 | for (i = 0; i < a->niov; i++) { |
| 475 | assert(a->iov[i].iov_len == b->iov[i].iov_len); |
| 476 | result = memcmp(a->iov[i].iov_base, |
| 477 | b->iov[i].iov_base, |
| 478 | a->iov[i].iov_len); |
| 479 | if (result) { |
| 480 | return false; |
| 481 | } |
| 482 | } |
| 483 | |
| 484 | return true; |
| 485 | } |
| 486 | |
| 487 | static void GCC_FMT_ATTR(2, 3) quorum_err(QuorumAIOCB *acb, |
| 488 | const char *fmt, ...) |
| 489 | { |
| 490 | va_list ap; |
| 491 | |
| 492 | va_start(ap, fmt); |
| 493 | fprintf(stderr, "quorum: sector_num=%" PRId64 " nb_sectors=%d ", |
| 494 | acb->sector_num, acb->nb_sectors); |
| 495 | vfprintf(stderr, fmt, ap); |
| 496 | fprintf(stderr, "\n"); |
| 497 | va_end(ap); |
| 498 | exit(1); |
| 499 | } |
| 500 | |
| 501 | static bool quorum_compare(QuorumAIOCB *acb, |
| 502 | QEMUIOVector *a, |
| 503 | QEMUIOVector *b) |
| 504 | { |
| 505 | BDRVQuorumState *s = acb->common.bs->opaque; |
| 506 | ssize_t offset; |
| 507 | |
| 508 | /* This driver will replace blkverify in this particular case */ |
| 509 | if (s->is_blkverify) { |
| 510 | offset = qemu_iovec_compare(a, b); |
| 511 | if (offset != -1) { |
| 512 | quorum_err(acb, "contents mismatch in sector %" PRId64, |
| 513 | acb->sector_num + |
| 514 | (uint64_t)(offset / BDRV_SECTOR_SIZE)); |
| 515 | } |
| 516 | return true; |
| 517 | } |
| 518 | |
| 519 | return quorum_iovec_compare(a, b); |
| 520 | } |
| 521 | |
| 522 | /* Do a vote to get the error code */ |
| 523 | static int quorum_vote_error(QuorumAIOCB *acb) |
| 524 | { |
| 525 | BDRVQuorumState *s = acb->common.bs->opaque; |
| 526 | QuorumVoteVersion *winner = NULL; |
| 527 | QuorumVotes error_votes; |
| 528 | QuorumVoteValue result_value; |
| 529 | int i, ret = 0; |
| 530 | bool error = false; |
| 531 | |
| 532 | QLIST_INIT(&error_votes.vote_list); |
| 533 | error_votes.compare = quorum_64bits_compare; |
| 534 | |
| 535 | for (i = 0; i < s->num_children; i++) { |
| 536 | ret = acb->qcrs[i].ret; |
| 537 | if (ret) { |
| 538 | error = true; |
| 539 | result_value.l = ret; |
| 540 | quorum_count_vote(&error_votes, &result_value, i); |
| 541 | } |
| 542 | } |
| 543 | |
| 544 | if (error) { |
| 545 | winner = quorum_get_vote_winner(&error_votes); |
| 546 | ret = winner->value.l; |
| 547 | } |
| 548 | |
| 549 | quorum_free_vote_list(&error_votes); |
| 550 | |
| 551 | return ret; |
| 552 | } |
| 553 | |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 554 | static bool quorum_vote(QuorumAIOCB *acb) |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 555 | { |
| 556 | bool quorum = true; |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 557 | bool rewrite = false; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 558 | int i, j, ret; |
| 559 | QuorumVoteValue hash; |
| 560 | BDRVQuorumState *s = acb->common.bs->opaque; |
| 561 | QuorumVoteVersion *winner; |
| 562 | |
| 563 | if (quorum_has_too_much_io_failed(acb)) { |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 564 | return false; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 565 | } |
| 566 | |
| 567 | /* get the index of the first successful read */ |
| 568 | for (i = 0; i < s->num_children; i++) { |
| 569 | if (!acb->qcrs[i].ret) { |
| 570 | break; |
| 571 | } |
| 572 | } |
| 573 | |
| 574 | assert(i < s->num_children); |
| 575 | |
| 576 | /* compare this read with all other successful reads stopping at quorum |
| 577 | * failure |
| 578 | */ |
| 579 | for (j = i + 1; j < s->num_children; j++) { |
| 580 | if (acb->qcrs[j].ret) { |
| 581 | continue; |
| 582 | } |
| 583 | quorum = quorum_compare(acb, &acb->qcrs[i].qiov, &acb->qcrs[j].qiov); |
| 584 | if (!quorum) { |
| 585 | break; |
| 586 | } |
| 587 | } |
| 588 | |
| 589 | /* Every successful read agrees */ |
| 590 | if (quorum) { |
| 591 | quorum_copy_qiov(acb->qiov, &acb->qcrs[i].qiov); |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 592 | return false; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 593 | } |
| 594 | |
| 595 | /* compute hashes for each successful read, also store indexes */ |
| 596 | for (i = 0; i < s->num_children; i++) { |
| 597 | if (acb->qcrs[i].ret) { |
| 598 | continue; |
| 599 | } |
| 600 | ret = quorum_compute_hash(acb, i, &hash); |
| 601 | /* if ever the hash computation failed */ |
| 602 | if (ret < 0) { |
| 603 | acb->vote_ret = ret; |
| 604 | goto free_exit; |
| 605 | } |
| 606 | quorum_count_vote(&acb->votes, &hash, i); |
| 607 | } |
| 608 | |
| 609 | /* vote to select the most represented version */ |
| 610 | winner = quorum_get_vote_winner(&acb->votes); |
| 611 | |
| 612 | /* if the winner count is smaller than threshold the read fails */ |
| 613 | if (winner->vote_count < s->threshold) { |
| 614 | quorum_report_failure(acb); |
| 615 | acb->vote_ret = -EIO; |
| 616 | goto free_exit; |
| 617 | } |
| 618 | |
| 619 | /* we have a winner: copy it */ |
| 620 | quorum_copy_qiov(acb->qiov, &acb->qcrs[winner->index].qiov); |
| 621 | |
| 622 | /* some versions are bad print them */ |
| 623 | quorum_report_bad_versions(s, acb, &winner->value); |
| 624 | |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 625 | /* corruption correction is enabled */ |
| 626 | if (s->rewrite_corrupted) { |
| 627 | rewrite = quorum_rewrite_bad_versions(s, acb, &winner->value); |
| 628 | } |
| 629 | |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 630 | free_exit: |
| 631 | /* free lists */ |
| 632 | quorum_free_vote_list(&acb->votes); |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 633 | return rewrite; |
Benoît Canet | 95c6bff | 2014-02-21 22:21:15 +0100 | [diff] [blame] | 634 | } |
| 635 | |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 636 | static BlockAIOCB *read_quorum_children(QuorumAIOCB *acb) |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 637 | { |
| 638 | BDRVQuorumState *s = acb->common.bs->opaque; |
| 639 | int i; |
| 640 | |
| 641 | for (i = 0; i < s->num_children; i++) { |
| 642 | acb->qcrs[i].buf = qemu_blockalign(s->bs[i], acb->qiov->size); |
| 643 | qemu_iovec_init(&acb->qcrs[i].qiov, acb->qiov->niov); |
| 644 | qemu_iovec_clone(&acb->qcrs[i].qiov, acb->qiov, acb->qcrs[i].buf); |
| 645 | } |
| 646 | |
| 647 | for (i = 0; i < s->num_children; i++) { |
| 648 | bdrv_aio_readv(s->bs[i], acb->sector_num, &acb->qcrs[i].qiov, |
| 649 | acb->nb_sectors, quorum_aio_cb, &acb->qcrs[i]); |
| 650 | } |
| 651 | |
| 652 | return &acb->common; |
| 653 | } |
| 654 | |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 655 | static BlockAIOCB *read_fifo_child(QuorumAIOCB *acb) |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 656 | { |
| 657 | BDRVQuorumState *s = acb->common.bs->opaque; |
| 658 | |
| 659 | acb->qcrs[acb->child_iter].buf = qemu_blockalign(s->bs[acb->child_iter], |
| 660 | acb->qiov->size); |
| 661 | qemu_iovec_init(&acb->qcrs[acb->child_iter].qiov, acb->qiov->niov); |
| 662 | qemu_iovec_clone(&acb->qcrs[acb->child_iter].qiov, acb->qiov, |
| 663 | acb->qcrs[acb->child_iter].buf); |
| 664 | bdrv_aio_readv(s->bs[acb->child_iter], acb->sector_num, |
| 665 | &acb->qcrs[acb->child_iter].qiov, acb->nb_sectors, |
| 666 | quorum_aio_cb, &acb->qcrs[acb->child_iter]); |
| 667 | |
| 668 | return &acb->common; |
| 669 | } |
| 670 | |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 671 | static BlockAIOCB *quorum_aio_readv(BlockDriverState *bs, |
| 672 | int64_t sector_num, |
| 673 | QEMUIOVector *qiov, |
| 674 | int nb_sectors, |
Markus Armbruster | 097310b | 2014-10-07 13:59:15 +0200 | [diff] [blame] | 675 | BlockCompletionFunc *cb, |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 676 | void *opaque) |
Benoît Canet | 7db6982 | 2014-02-21 22:21:14 +0100 | [diff] [blame] | 677 | { |
| 678 | BDRVQuorumState *s = bs->opaque; |
| 679 | QuorumAIOCB *acb = quorum_aio_get(s, bs, qiov, sector_num, |
| 680 | nb_sectors, cb, opaque); |
Benoît Canet | 7db6982 | 2014-02-21 22:21:14 +0100 | [diff] [blame] | 681 | acb->is_read = true; |
| 682 | |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 683 | if (s->read_pattern == QUORUM_READ_PATTERN_QUORUM) { |
| 684 | acb->child_iter = s->num_children - 1; |
| 685 | return read_quorum_children(acb); |
Benoît Canet | 7db6982 | 2014-02-21 22:21:14 +0100 | [diff] [blame] | 686 | } |
| 687 | |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 688 | acb->child_iter = 0; |
| 689 | return read_fifo_child(acb); |
Benoît Canet | 7db6982 | 2014-02-21 22:21:14 +0100 | [diff] [blame] | 690 | } |
| 691 | |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 692 | static BlockAIOCB *quorum_aio_writev(BlockDriverState *bs, |
| 693 | int64_t sector_num, |
| 694 | QEMUIOVector *qiov, |
| 695 | int nb_sectors, |
Markus Armbruster | 097310b | 2014-10-07 13:59:15 +0200 | [diff] [blame] | 696 | BlockCompletionFunc *cb, |
Markus Armbruster | 7c84b1b | 2014-10-07 13:59:14 +0200 | [diff] [blame] | 697 | void *opaque) |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 698 | { |
| 699 | BDRVQuorumState *s = bs->opaque; |
| 700 | QuorumAIOCB *acb = quorum_aio_get(s, bs, qiov, sector_num, nb_sectors, |
| 701 | cb, opaque); |
| 702 | int i; |
| 703 | |
| 704 | for (i = 0; i < s->num_children; i++) { |
| 705 | acb->qcrs[i].aiocb = bdrv_aio_writev(s->bs[i], sector_num, qiov, |
| 706 | nb_sectors, &quorum_aio_cb, |
| 707 | &acb->qcrs[i]); |
| 708 | } |
| 709 | |
| 710 | return &acb->common; |
| 711 | } |
| 712 | |
Benoît Canet | d55dee2 | 2014-02-21 22:21:16 +0100 | [diff] [blame] | 713 | static int64_t quorum_getlength(BlockDriverState *bs) |
| 714 | { |
| 715 | BDRVQuorumState *s = bs->opaque; |
| 716 | int64_t result; |
| 717 | int i; |
| 718 | |
| 719 | /* check that all file have the same length */ |
| 720 | result = bdrv_getlength(s->bs[0]); |
| 721 | if (result < 0) { |
| 722 | return result; |
| 723 | } |
| 724 | for (i = 1; i < s->num_children; i++) { |
| 725 | int64_t value = bdrv_getlength(s->bs[i]); |
| 726 | if (value < 0) { |
| 727 | return value; |
| 728 | } |
| 729 | if (value != result) { |
| 730 | return -EIO; |
| 731 | } |
| 732 | } |
| 733 | |
| 734 | return result; |
| 735 | } |
| 736 | |
Kevin Wolf | 5a8a30d | 2014-03-12 15:59:16 +0100 | [diff] [blame] | 737 | static void quorum_invalidate_cache(BlockDriverState *bs, Error **errp) |
Benoît Canet | a28e4c4 | 2014-02-21 22:21:17 +0100 | [diff] [blame] | 738 | { |
| 739 | BDRVQuorumState *s = bs->opaque; |
Kevin Wolf | 5a8a30d | 2014-03-12 15:59:16 +0100 | [diff] [blame] | 740 | Error *local_err = NULL; |
Benoît Canet | a28e4c4 | 2014-02-21 22:21:17 +0100 | [diff] [blame] | 741 | int i; |
| 742 | |
| 743 | for (i = 0; i < s->num_children; i++) { |
Kevin Wolf | 5a8a30d | 2014-03-12 15:59:16 +0100 | [diff] [blame] | 744 | bdrv_invalidate_cache(s->bs[i], &local_err); |
| 745 | if (local_err) { |
| 746 | error_propagate(errp, local_err); |
| 747 | return; |
| 748 | } |
Benoît Canet | a28e4c4 | 2014-02-21 22:21:17 +0100 | [diff] [blame] | 749 | } |
| 750 | } |
| 751 | |
Benoît Canet | 1c508d1 | 2014-02-21 22:21:18 +0100 | [diff] [blame] | 752 | static coroutine_fn int quorum_co_flush(BlockDriverState *bs) |
| 753 | { |
| 754 | BDRVQuorumState *s = bs->opaque; |
| 755 | QuorumVoteVersion *winner = NULL; |
| 756 | QuorumVotes error_votes; |
| 757 | QuorumVoteValue result_value; |
| 758 | int i; |
| 759 | int result = 0; |
| 760 | |
| 761 | QLIST_INIT(&error_votes.vote_list); |
| 762 | error_votes.compare = quorum_64bits_compare; |
| 763 | |
| 764 | for (i = 0; i < s->num_children; i++) { |
| 765 | result = bdrv_co_flush(s->bs[i]); |
| 766 | result_value.l = result; |
| 767 | quorum_count_vote(&error_votes, &result_value, i); |
| 768 | } |
| 769 | |
| 770 | winner = quorum_get_vote_winner(&error_votes); |
| 771 | result = winner->value.l; |
| 772 | |
| 773 | quorum_free_vote_list(&error_votes); |
| 774 | |
| 775 | return result; |
| 776 | } |
| 777 | |
Benoît Canet | 98a7a38 | 2014-02-21 22:21:19 +0100 | [diff] [blame] | 778 | static bool quorum_recurse_is_first_non_filter(BlockDriverState *bs, |
| 779 | BlockDriverState *candidate) |
| 780 | { |
| 781 | BDRVQuorumState *s = bs->opaque; |
| 782 | int i; |
| 783 | |
| 784 | for (i = 0; i < s->num_children; i++) { |
| 785 | bool perm = bdrv_recurse_is_first_non_filter(s->bs[i], |
| 786 | candidate); |
| 787 | if (perm) { |
| 788 | return true; |
| 789 | } |
| 790 | } |
| 791 | |
| 792 | return false; |
| 793 | } |
| 794 | |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 795 | static int quorum_valid_threshold(int threshold, int num_children, Error **errp) |
| 796 | { |
| 797 | |
| 798 | if (threshold < 1) { |
Markus Armbruster | c6bd8c7 | 2015-03-17 11:54:50 +0100 | [diff] [blame] | 799 | error_setg(errp, QERR_INVALID_PARAMETER_VALUE, |
| 800 | "vote-threshold", "value >= 1"); |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 801 | return -ERANGE; |
| 802 | } |
| 803 | |
| 804 | if (threshold > num_children) { |
| 805 | error_setg(errp, "threshold may not exceed children count"); |
| 806 | return -ERANGE; |
| 807 | } |
| 808 | |
| 809 | return 0; |
| 810 | } |
| 811 | |
| 812 | static QemuOptsList quorum_runtime_opts = { |
| 813 | .name = "quorum", |
| 814 | .head = QTAILQ_HEAD_INITIALIZER(quorum_runtime_opts.head), |
| 815 | .desc = { |
| 816 | { |
| 817 | .name = QUORUM_OPT_VOTE_THRESHOLD, |
| 818 | .type = QEMU_OPT_NUMBER, |
| 819 | .help = "The number of vote needed for reaching quorum", |
| 820 | }, |
| 821 | { |
| 822 | .name = QUORUM_OPT_BLKVERIFY, |
| 823 | .type = QEMU_OPT_BOOL, |
| 824 | .help = "Trigger block verify mode if set", |
| 825 | }, |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 826 | { |
| 827 | .name = QUORUM_OPT_REWRITE, |
| 828 | .type = QEMU_OPT_BOOL, |
| 829 | .help = "Rewrite corrupted block on read quorum", |
| 830 | }, |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 831 | { |
| 832 | .name = QUORUM_OPT_READ_PATTERN, |
| 833 | .type = QEMU_OPT_STRING, |
| 834 | .help = "Allowed pattern: quorum, fifo. Quorum is default", |
| 835 | }, |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 836 | { /* end of list */ } |
| 837 | }, |
| 838 | }; |
| 839 | |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 840 | static int parse_read_pattern(const char *opt) |
| 841 | { |
| 842 | int i; |
| 843 | |
| 844 | if (!opt) { |
| 845 | /* Set quorum as default */ |
| 846 | return QUORUM_READ_PATTERN_QUORUM; |
| 847 | } |
| 848 | |
| 849 | for (i = 0; i < QUORUM_READ_PATTERN_MAX; i++) { |
| 850 | if (!strcmp(opt, QuorumReadPattern_lookup[i])) { |
| 851 | return i; |
| 852 | } |
| 853 | } |
| 854 | |
| 855 | return -EINVAL; |
| 856 | } |
| 857 | |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 858 | static int quorum_open(BlockDriverState *bs, QDict *options, int flags, |
| 859 | Error **errp) |
| 860 | { |
| 861 | BDRVQuorumState *s = bs->opaque; |
| 862 | Error *local_err = NULL; |
Fam Zheng | 8df3abf | 2014-08-28 13:56:12 +0800 | [diff] [blame] | 863 | QemuOpts *opts = NULL; |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 864 | bool *opened; |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 865 | int i; |
| 866 | int ret = 0; |
| 867 | |
| 868 | qdict_flatten(options); |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 869 | |
Kevin Wolf | ea6828d | 2015-01-21 18:49:28 +0100 | [diff] [blame] | 870 | /* count how many different children are present */ |
| 871 | s->num_children = qdict_array_entries(options, "children."); |
| 872 | if (s->num_children < 0) { |
| 873 | error_setg(&local_err, "Option children is not a valid array"); |
Max Reitz | 8a87f3d | 2014-02-21 22:30:37 +0100 | [diff] [blame] | 874 | ret = -EINVAL; |
| 875 | goto exit; |
| 876 | } |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 877 | if (s->num_children < 2) { |
| 878 | error_setg(&local_err, |
| 879 | "Number of provided children must be greater than 1"); |
| 880 | ret = -EINVAL; |
| 881 | goto exit; |
| 882 | } |
| 883 | |
| 884 | opts = qemu_opts_create(&quorum_runtime_opts, NULL, 0, &error_abort); |
| 885 | qemu_opts_absorb_qdict(opts, options, &local_err); |
Markus Armbruster | 0fb6395 | 2014-04-25 16:50:31 +0200 | [diff] [blame] | 886 | if (local_err) { |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 887 | ret = -EINVAL; |
| 888 | goto exit; |
| 889 | } |
| 890 | |
| 891 | s->threshold = qemu_opt_get_number(opts, QUORUM_OPT_VOTE_THRESHOLD, 0); |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 892 | ret = parse_read_pattern(qemu_opt_get(opts, QUORUM_OPT_READ_PATTERN)); |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 893 | if (ret < 0) { |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 894 | error_setg(&local_err, "Please set read-pattern as fifo or quorum"); |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 895 | goto exit; |
| 896 | } |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 897 | s->read_pattern = ret; |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 898 | |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 899 | if (s->read_pattern == QUORUM_READ_PATTERN_QUORUM) { |
| 900 | /* and validate it against s->num_children */ |
| 901 | ret = quorum_valid_threshold(s->threshold, s->num_children, &local_err); |
| 902 | if (ret < 0) { |
| 903 | goto exit; |
| 904 | } |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 905 | |
Liu Yuan | a9db86b | 2014-08-18 17:41:05 +0800 | [diff] [blame] | 906 | /* is the driver in blkverify mode */ |
| 907 | if (qemu_opt_get_bool(opts, QUORUM_OPT_BLKVERIFY, false) && |
| 908 | s->num_children == 2 && s->threshold == 2) { |
| 909 | s->is_blkverify = true; |
| 910 | } else if (qemu_opt_get_bool(opts, QUORUM_OPT_BLKVERIFY, false)) { |
| 911 | fprintf(stderr, "blkverify mode is set by setting blkverify=on " |
| 912 | "and using two files with vote_threshold=2\n"); |
| 913 | } |
| 914 | |
| 915 | s->rewrite_corrupted = qemu_opt_get_bool(opts, QUORUM_OPT_REWRITE, |
| 916 | false); |
| 917 | if (s->rewrite_corrupted && s->is_blkverify) { |
| 918 | error_setg(&local_err, |
| 919 | "rewrite-corrupted=on cannot be used with blkverify=on"); |
| 920 | ret = -EINVAL; |
| 921 | goto exit; |
| 922 | } |
Benoît Canet | cf29a57 | 2014-06-11 15:24:10 +0200 | [diff] [blame] | 923 | } |
| 924 | |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 925 | /* allocate the children BlockDriverState array */ |
| 926 | s->bs = g_new0(BlockDriverState *, s->num_children); |
| 927 | opened = g_new0(bool, s->num_children); |
| 928 | |
Kevin Wolf | ea6828d | 2015-01-21 18:49:28 +0100 | [diff] [blame] | 929 | for (i = 0; i < s->num_children; i++) { |
| 930 | char indexstr[32]; |
| 931 | ret = snprintf(indexstr, 32, "children.%d", i); |
| 932 | assert(ret < 32); |
Max Reitz | 8a87f3d | 2014-02-21 22:30:37 +0100 | [diff] [blame] | 933 | |
Kevin Wolf | f3930ed | 2015-04-08 13:43:47 +0200 | [diff] [blame] | 934 | ret = bdrv_open_image(&s->bs[i], NULL, options, indexstr, bs, |
| 935 | &child_format, false, &local_err); |
Max Reitz | 8a87f3d | 2014-02-21 22:30:37 +0100 | [diff] [blame] | 936 | if (ret < 0) { |
| 937 | goto close_exit; |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 938 | } |
Kevin Wolf | ea6828d | 2015-01-21 18:49:28 +0100 | [diff] [blame] | 939 | |
Max Reitz | 8a87f3d | 2014-02-21 22:30:37 +0100 | [diff] [blame] | 940 | opened[i] = true; |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 941 | } |
| 942 | |
| 943 | g_free(opened); |
| 944 | goto exit; |
| 945 | |
| 946 | close_exit: |
| 947 | /* cleanup on error */ |
| 948 | for (i = 0; i < s->num_children; i++) { |
| 949 | if (!opened[i]) { |
| 950 | continue; |
| 951 | } |
| 952 | bdrv_unref(s->bs[i]); |
| 953 | } |
| 954 | g_free(s->bs); |
| 955 | g_free(opened); |
| 956 | exit: |
Fam Zheng | 8df3abf | 2014-08-28 13:56:12 +0800 | [diff] [blame] | 957 | qemu_opts_del(opts); |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 958 | /* propagate error */ |
Markus Armbruster | 0fb6395 | 2014-04-25 16:50:31 +0200 | [diff] [blame] | 959 | if (local_err) { |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 960 | error_propagate(errp, local_err); |
| 961 | } |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 962 | return ret; |
| 963 | } |
| 964 | |
| 965 | static void quorum_close(BlockDriverState *bs) |
| 966 | { |
| 967 | BDRVQuorumState *s = bs->opaque; |
| 968 | int i; |
| 969 | |
| 970 | for (i = 0; i < s->num_children; i++) { |
| 971 | bdrv_unref(s->bs[i]); |
| 972 | } |
| 973 | |
| 974 | g_free(s->bs); |
| 975 | } |
| 976 | |
Stefan Hajnoczi | e3625d3 | 2014-05-08 16:34:46 +0200 | [diff] [blame] | 977 | static void quorum_detach_aio_context(BlockDriverState *bs) |
| 978 | { |
| 979 | BDRVQuorumState *s = bs->opaque; |
| 980 | int i; |
| 981 | |
| 982 | for (i = 0; i < s->num_children; i++) { |
| 983 | bdrv_detach_aio_context(s->bs[i]); |
| 984 | } |
| 985 | } |
| 986 | |
| 987 | static void quorum_attach_aio_context(BlockDriverState *bs, |
| 988 | AioContext *new_context) |
| 989 | { |
| 990 | BDRVQuorumState *s = bs->opaque; |
| 991 | int i; |
| 992 | |
| 993 | for (i = 0; i < s->num_children; i++) { |
| 994 | bdrv_attach_aio_context(s->bs[i], new_context); |
| 995 | } |
| 996 | } |
| 997 | |
Max Reitz | fafcfe2 | 2014-07-18 20:25:00 +0200 | [diff] [blame] | 998 | static void quorum_refresh_filename(BlockDriverState *bs) |
| 999 | { |
| 1000 | BDRVQuorumState *s = bs->opaque; |
| 1001 | QDict *opts; |
| 1002 | QList *children; |
| 1003 | int i; |
| 1004 | |
| 1005 | for (i = 0; i < s->num_children; i++) { |
| 1006 | bdrv_refresh_filename(s->bs[i]); |
| 1007 | if (!s->bs[i]->full_open_options) { |
| 1008 | return; |
| 1009 | } |
| 1010 | } |
| 1011 | |
| 1012 | children = qlist_new(); |
| 1013 | for (i = 0; i < s->num_children; i++) { |
| 1014 | QINCREF(s->bs[i]->full_open_options); |
| 1015 | qlist_append_obj(children, QOBJECT(s->bs[i]->full_open_options)); |
| 1016 | } |
| 1017 | |
| 1018 | opts = qdict_new(); |
| 1019 | qdict_put_obj(opts, "driver", QOBJECT(qstring_from_str("quorum"))); |
| 1020 | qdict_put_obj(opts, QUORUM_OPT_VOTE_THRESHOLD, |
| 1021 | QOBJECT(qint_from_int(s->threshold))); |
| 1022 | qdict_put_obj(opts, QUORUM_OPT_BLKVERIFY, |
Eric Blake | fc48ffc | 2015-05-15 16:24:59 -0600 | [diff] [blame] | 1023 | QOBJECT(qbool_from_bool(s->is_blkverify))); |
Max Reitz | fafcfe2 | 2014-07-18 20:25:00 +0200 | [diff] [blame] | 1024 | qdict_put_obj(opts, QUORUM_OPT_REWRITE, |
Eric Blake | fc48ffc | 2015-05-15 16:24:59 -0600 | [diff] [blame] | 1025 | QOBJECT(qbool_from_bool(s->rewrite_corrupted))); |
Max Reitz | fafcfe2 | 2014-07-18 20:25:00 +0200 | [diff] [blame] | 1026 | qdict_put_obj(opts, "children", QOBJECT(children)); |
| 1027 | |
| 1028 | bs->full_open_options = opts; |
| 1029 | } |
| 1030 | |
Benoît Canet | cadebd7 | 2014-02-21 22:21:11 +0100 | [diff] [blame] | 1031 | static BlockDriver bdrv_quorum = { |
Stefan Hajnoczi | e3625d3 | 2014-05-08 16:34:46 +0200 | [diff] [blame] | 1032 | .format_name = "quorum", |
| 1033 | .protocol_name = "quorum", |
Benoît Canet | cadebd7 | 2014-02-21 22:21:11 +0100 | [diff] [blame] | 1034 | |
Stefan Hajnoczi | e3625d3 | 2014-05-08 16:34:46 +0200 | [diff] [blame] | 1035 | .instance_size = sizeof(BDRVQuorumState), |
Benoît Canet | 13e7956 | 2014-02-21 22:21:12 +0100 | [diff] [blame] | 1036 | |
Stefan Hajnoczi | e3625d3 | 2014-05-08 16:34:46 +0200 | [diff] [blame] | 1037 | .bdrv_file_open = quorum_open, |
| 1038 | .bdrv_close = quorum_close, |
Max Reitz | fafcfe2 | 2014-07-18 20:25:00 +0200 | [diff] [blame] | 1039 | .bdrv_refresh_filename = quorum_refresh_filename, |
Benoît Canet | c88a1de | 2014-02-21 22:21:20 +0100 | [diff] [blame] | 1040 | |
Stefan Hajnoczi | e3625d3 | 2014-05-08 16:34:46 +0200 | [diff] [blame] | 1041 | .bdrv_co_flush_to_disk = quorum_co_flush, |
Benoît Canet | 1c508d1 | 2014-02-21 22:21:18 +0100 | [diff] [blame] | 1042 | |
Stefan Hajnoczi | e3625d3 | 2014-05-08 16:34:46 +0200 | [diff] [blame] | 1043 | .bdrv_getlength = quorum_getlength, |
Benoît Canet | d55dee2 | 2014-02-21 22:21:16 +0100 | [diff] [blame] | 1044 | |
Stefan Hajnoczi | e3625d3 | 2014-05-08 16:34:46 +0200 | [diff] [blame] | 1045 | .bdrv_aio_readv = quorum_aio_readv, |
| 1046 | .bdrv_aio_writev = quorum_aio_writev, |
| 1047 | .bdrv_invalidate_cache = quorum_invalidate_cache, |
Benoît Canet | 98a7a38 | 2014-02-21 22:21:19 +0100 | [diff] [blame] | 1048 | |
Stefan Hajnoczi | e3625d3 | 2014-05-08 16:34:46 +0200 | [diff] [blame] | 1049 | .bdrv_detach_aio_context = quorum_detach_aio_context, |
| 1050 | .bdrv_attach_aio_context = quorum_attach_aio_context, |
| 1051 | |
| 1052 | .is_filter = true, |
| 1053 | .bdrv_recurse_is_first_non_filter = quorum_recurse_is_first_non_filter, |
Benoît Canet | cadebd7 | 2014-02-21 22:21:11 +0100 | [diff] [blame] | 1054 | }; |
| 1055 | |
| 1056 | static void bdrv_quorum_init(void) |
| 1057 | { |
Sascha Silbe | e94867e | 2015-08-04 16:48:25 +0200 | [diff] [blame^] | 1058 | if (!qcrypto_hash_supports(QCRYPTO_HASH_ALG_SHA256)) { |
| 1059 | /* SHA256 hash support is required for quorum device */ |
| 1060 | return; |
| 1061 | } |
Benoît Canet | cadebd7 | 2014-02-21 22:21:11 +0100 | [diff] [blame] | 1062 | bdrv_register(&bdrv_quorum); |
| 1063 | } |
| 1064 | |
| 1065 | block_init(bdrv_quorum_init); |