1 /* Copyright (c) 2009, 2010, 2011 Nicira Networks
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
18 #include "transaction.h"
23 #include "dynamic-string.h"
28 #include "ovsdb-error.h"
36 struct list txn_tables; /* Contains "struct ovsdb_txn_table"s. */
40 /* A table modified by a transaction. */
41 struct ovsdb_txn_table {
42 struct list node; /* Element in ovsdb_txn's txn_tables list. */
43 struct ovsdb_table *table;
44 struct hmap txn_rows; /* Contains "struct ovsdb_txn_row"s. */
46 /* This has the same form as the 'indexes' member of struct ovsdb_table,
47 * but it is only used or updated at transaction commit time, from
48 * check_index_uniqueness(). */
49 struct hmap *txn_indexes;
51 /* Used by for_each_txn_row(). */
52 unsigned int serial; /* Serial number of in-progress iteration. */
53 unsigned int n_processed; /* Number of rows processed. */
56 /* A row modified by the transaction:
58 * - A row added by a transaction will have null 'old' and non-null 'new'.
60 * - A row deleted by a transaction will have non-null 'old' and null
63 * - A row modified by a transaction will have non-null 'old' and 'new'.
65 * - 'old' and 'new' both null indicates that a row was added then deleted
66 * within a single transaction. Most of the time we instead delete the
67 * ovsdb_txn_row entirely, but inside a for_each_txn_row() callback
68 * there are restrictions that sometimes mean we have to leave the
69 * ovsdb_txn_row in place.
71 struct ovsdb_txn_row {
72 struct hmap_node hmap_node; /* In ovsdb_txn_table's txn_rows hmap. */
73 struct ovsdb_row *old; /* The old row. */
74 struct ovsdb_row *new; /* The new row. */
75 size_t n_refs; /* Number of remaining references. */
77 /* These members are the same as the corresponding members of 'old' or
78 * 'new'. They are present here for convenience and because occasionally
79 * there can be an ovsdb_txn_row where both 'old' and 'new' are NULL. */
81 struct ovsdb_table *table;
83 /* Used by for_each_txn_row(). */
84 unsigned int serial; /* Serial number of in-progress commit. */
86 unsigned long changed[]; /* Bits set to 1 for columns that changed. */
89 static struct ovsdb_error * WARN_UNUSED_RESULT
90 delete_garbage_row(struct ovsdb_txn *txn, struct ovsdb_txn_row *r);
91 static void ovsdb_txn_row_prefree(struct ovsdb_txn_row *);
92 static struct ovsdb_error * WARN_UNUSED_RESULT
93 for_each_txn_row(struct ovsdb_txn *txn,
94 struct ovsdb_error *(*)(struct ovsdb_txn *,
95 struct ovsdb_txn_row *));
97 /* Used by for_each_txn_row() to track tables and rows that have been
99 static unsigned int serial;
102 ovsdb_txn_create(struct ovsdb *db)
104 struct ovsdb_txn *txn = xmalloc(sizeof *txn);
106 list_init(&txn->txn_tables);
107 ds_init(&txn->comment);
112 ovsdb_txn_free(struct ovsdb_txn *txn)
114 assert(list_is_empty(&txn->txn_tables));
115 ds_destroy(&txn->comment);
119 static struct ovsdb_error *
120 ovsdb_txn_row_abort(struct ovsdb_txn *txn OVS_UNUSED,
121 struct ovsdb_txn_row *txn_row)
123 struct ovsdb_row *old = txn_row->old;
124 struct ovsdb_row *new = txn_row->new;
126 ovsdb_txn_row_prefree(txn_row);
129 hmap_remove(&new->table->rows, &new->hmap_node);
132 hmap_insert(&old->table->rows, &old->hmap_node, ovsdb_row_hash(old));
134 hmap_replace(&new->table->rows, &new->hmap_node, &old->hmap_node);
136 ovsdb_row_destroy(new);
142 /* Returns the offset in bytes from the start of an ovsdb_row for 'table' to
143 * the hmap_node for the index numbered 'i'. */
145 ovsdb_row_index_offset__(const struct ovsdb_table *table, size_t i)
147 size_t n_fields = shash_count(&table->schema->columns);
148 return (offsetof(struct ovsdb_row, fields)
149 + n_fields * sizeof(struct ovsdb_datum)
150 + i * sizeof(struct hmap_node));
153 /* Returns the hmap_node in 'row' for the index numbered 'i'. */
154 static struct hmap_node *
155 ovsdb_row_get_index_node(struct ovsdb_row *row, size_t i)
157 return (void *) ((char *) row + ovsdb_row_index_offset__(row->table, i));
160 /* Returns the ovsdb_row given 'index_node', which is a pointer to that row's
161 * hmap_node for the index numbered 'i' within 'table'. */
162 static struct ovsdb_row *
163 ovsdb_row_from_index_node(struct hmap_node *index_node,
164 const struct ovsdb_table *table, size_t i)
166 return (void *) ((char *) index_node - ovsdb_row_index_offset__(table, i));
170 ovsdb_txn_abort(struct ovsdb_txn *txn)
172 ovsdb_error_assert(for_each_txn_row(txn, ovsdb_txn_row_abort));
176 static struct ovsdb_txn_row *
177 find_txn_row(const struct ovsdb_table *table, const struct uuid *uuid)
179 struct ovsdb_txn_row *txn_row;
181 if (!table->txn_table) {
185 HMAP_FOR_EACH_WITH_HASH (txn_row, hmap_node,
186 uuid_hash(uuid), &table->txn_table->txn_rows) {
187 if (uuid_equals(uuid, &txn_row->uuid)) {
195 static struct ovsdb_txn_row *
196 find_or_make_txn_row(struct ovsdb_txn *txn, const struct ovsdb_table *table,
197 const struct uuid *uuid)
199 struct ovsdb_txn_row *txn_row = find_txn_row(table, uuid);
201 const struct ovsdb_row *row = ovsdb_table_get_row(table, uuid);
203 txn_row = ovsdb_txn_row_modify(txn, row)->txn_row;
209 static struct ovsdb_error * WARN_UNUSED_RESULT
210 ovsdb_txn_adjust_atom_refs(struct ovsdb_txn *txn, const struct ovsdb_row *r,
211 const struct ovsdb_column *c,
212 const struct ovsdb_base_type *base,
213 const union ovsdb_atom *atoms, unsigned int n,
216 const struct ovsdb_table *table;
219 if (!ovsdb_base_type_is_strong_ref(base)) {
223 table = base->u.uuid.refTable;
224 for (i = 0; i < n; i++) {
225 const struct uuid *uuid = &atoms[i].uuid;
226 struct ovsdb_txn_row *txn_row;
228 if (uuid_equals(uuid, ovsdb_row_get_uuid(r))) {
229 /* Self-references don't count. */
233 txn_row = find_or_make_txn_row(txn, table, uuid);
235 return ovsdb_error("referential integrity violation",
236 "Table %s column %s row "UUID_FMT" "
237 "references nonexistent row "UUID_FMT" in "
239 r->table->schema->name, c->name,
240 UUID_ARGS(ovsdb_row_get_uuid(r)),
241 UUID_ARGS(uuid), table->schema->name);
243 txn_row->n_refs += delta;
249 static struct ovsdb_error * WARN_UNUSED_RESULT
250 ovsdb_txn_adjust_row_refs(struct ovsdb_txn *txn, const struct ovsdb_row *r,
251 const struct ovsdb_column *column, int delta)
253 const struct ovsdb_datum *field = &r->fields[column->index];
254 struct ovsdb_error *error;
256 error = ovsdb_txn_adjust_atom_refs(txn, r, column, &column->type.key,
257 field->keys, field->n, delta);
259 error = ovsdb_txn_adjust_atom_refs(txn, r, column, &column->type.value,
260 field->values, field->n, delta);
265 static struct ovsdb_error * WARN_UNUSED_RESULT
266 update_row_ref_count(struct ovsdb_txn *txn, struct ovsdb_txn_row *r)
268 struct ovsdb_table *table = r->table;
269 struct shash_node *node;
271 SHASH_FOR_EACH (node, &table->schema->columns) {
272 const struct ovsdb_column *column = node->data;
273 struct ovsdb_error *error;
276 error = ovsdb_txn_adjust_row_refs(txn, r->old, column, -1);
278 return OVSDB_WRAP_BUG("error decreasing refcount", error);
282 error = ovsdb_txn_adjust_row_refs(txn, r->new, column, 1);
292 static struct ovsdb_error * WARN_UNUSED_RESULT
293 check_ref_count(struct ovsdb_txn *txn OVS_UNUSED, struct ovsdb_txn_row *r)
295 if (r->new || !r->n_refs) {
298 return ovsdb_error("referential integrity violation",
299 "cannot delete %s row "UUID_FMT" because "
300 "of %zu remaining reference(s)",
301 r->table->schema->name, UUID_ARGS(&r->uuid),
306 static struct ovsdb_error * WARN_UNUSED_RESULT
307 delete_row_refs(struct ovsdb_txn *txn, const struct ovsdb_row *row,
308 const struct ovsdb_base_type *base,
309 const union ovsdb_atom *atoms, unsigned int n)
311 const struct ovsdb_table *table;
314 if (!ovsdb_base_type_is_strong_ref(base)) {
318 table = base->u.uuid.refTable;
319 for (i = 0; i < n; i++) {
320 const struct uuid *uuid = &atoms[i].uuid;
321 struct ovsdb_txn_row *txn_row;
323 if (uuid_equals(uuid, ovsdb_row_get_uuid(row))) {
324 /* Self-references don't count. */
328 txn_row = find_or_make_txn_row(txn, table, uuid);
330 return OVSDB_BUG("strong ref target missing");
331 } else if (!txn_row->n_refs) {
332 return OVSDB_BUG("strong ref target has zero n_refs");
333 } else if (!txn_row->new) {
334 return OVSDB_BUG("deleted strong ref target");
337 if (--txn_row->n_refs == 0) {
338 struct ovsdb_error *error = delete_garbage_row(txn, txn_row);
348 static struct ovsdb_error * WARN_UNUSED_RESULT
349 delete_garbage_row(struct ovsdb_txn *txn, struct ovsdb_txn_row *txn_row)
351 struct shash_node *node;
352 struct ovsdb_row *row;
354 if (txn_row->table->schema->is_root) {
360 hmap_remove(&txn_row->table->rows, &row->hmap_node);
361 SHASH_FOR_EACH (node, &txn_row->table->schema->columns) {
362 const struct ovsdb_column *column = node->data;
363 const struct ovsdb_datum *field = &row->fields[column->index];
364 struct ovsdb_error *error;
366 error = delete_row_refs(txn, row,
367 &column->type.key, field->keys, field->n);
372 error = delete_row_refs(txn, row,
373 &column->type.value, field->values, field->n);
378 ovsdb_row_destroy(row);
383 static struct ovsdb_error * WARN_UNUSED_RESULT
384 collect_garbage(struct ovsdb_txn *txn, struct ovsdb_txn_row *txn_row)
386 if (txn_row->new && !txn_row->n_refs) {
387 return delete_garbage_row(txn, txn_row);
392 static struct ovsdb_error * WARN_UNUSED_RESULT
393 update_ref_counts(struct ovsdb_txn *txn)
395 struct ovsdb_error *error;
397 error = for_each_txn_row(txn, update_row_ref_count);
402 return for_each_txn_row(txn, check_ref_count);
405 static struct ovsdb_error *
406 ovsdb_txn_row_commit(struct ovsdb_txn *txn OVS_UNUSED,
407 struct ovsdb_txn_row *txn_row)
409 size_t n_indexes = txn_row->table->schema->n_indexes;
414 for (i = 0; i < n_indexes; i++) {
415 struct hmap_node *node = ovsdb_row_get_index_node(txn_row->old, i);
416 hmap_remove(&txn_row->table->indexes[i], node);
422 for (i = 0; i < n_indexes; i++) {
423 struct hmap_node *node = ovsdb_row_get_index_node(txn_row->new, i);
424 hmap_insert(&txn_row->table->indexes[i], node, node->hash);
428 ovsdb_txn_row_prefree(txn_row);
430 txn_row->new->n_refs = txn_row->n_refs;
432 ovsdb_row_destroy(txn_row->old);
439 add_weak_ref(struct ovsdb_txn *txn,
440 const struct ovsdb_row *src_, const struct ovsdb_row *dst_)
442 struct ovsdb_row *src = (struct ovsdb_row *) src_;
443 struct ovsdb_row *dst = (struct ovsdb_row *) dst_;
444 struct ovsdb_weak_ref *weak;
450 dst = ovsdb_txn_row_modify(txn, dst);
452 if (!list_is_empty(&dst->dst_refs)) {
453 /* Omit duplicates. */
454 weak = CONTAINER_OF(list_back(&dst->dst_refs),
455 struct ovsdb_weak_ref, dst_node);
456 if (weak->src == src) {
461 weak = xmalloc(sizeof *weak);
463 list_push_back(&dst->dst_refs, &weak->dst_node);
464 list_push_back(&src->src_refs, &weak->src_node);
467 static struct ovsdb_error * WARN_UNUSED_RESULT
468 assess_weak_refs(struct ovsdb_txn *txn, struct ovsdb_txn_row *txn_row)
470 struct ovsdb_table *table;
471 struct shash_node *node;
474 /* Mark rows that have weak references to 'txn_row' as modified, so
475 * that their weak references will get reassessed. */
476 struct ovsdb_weak_ref *weak, *next;
478 LIST_FOR_EACH_SAFE (weak, next, dst_node, &txn_row->old->dst_refs) {
479 if (!weak->src->txn_row) {
480 ovsdb_txn_row_modify(txn, weak->src);
486 /* We don't have to do anything about references that originate at
487 * 'txn_row', because ovsdb_row_destroy() will remove those weak
492 table = txn_row->table;
493 SHASH_FOR_EACH (node, &table->schema->columns) {
494 const struct ovsdb_column *column = node->data;
495 struct ovsdb_datum *datum = &txn_row->new->fields[column->index];
496 unsigned int orig_n, i;
501 if (ovsdb_base_type_is_weak_ref(&column->type.key)) {
502 for (i = 0; i < datum->n; ) {
503 const struct ovsdb_row *row;
505 row = ovsdb_table_get_row(column->type.key.u.uuid.refTable,
506 &datum->keys[i].uuid);
508 add_weak_ref(txn, txn_row->new, row);
511 if (uuid_is_zero(&datum->keys[i].uuid)) {
514 ovsdb_datum_remove_unsafe(datum, i, &column->type);
519 if (ovsdb_base_type_is_weak_ref(&column->type.value)) {
520 for (i = 0; i < datum->n; ) {
521 const struct ovsdb_row *row;
523 row = ovsdb_table_get_row(column->type.value.u.uuid.refTable,
524 &datum->values[i].uuid);
526 add_weak_ref(txn, txn_row->new, row);
529 if (uuid_is_zero(&datum->values[i].uuid)) {
532 ovsdb_datum_remove_unsafe(datum, i, &column->type);
537 if (datum->n != orig_n) {
538 bitmap_set1(txn_row->changed, column->index);
539 ovsdb_datum_sort_assert(datum, column->type.key.type);
540 if (datum->n < column->type.n_min) {
541 const struct uuid *row_uuid = ovsdb_row_get_uuid(txn_row->new);
542 if (zero && !txn_row->old) {
544 "constraint violation",
545 "Weak reference column \"%s\" in \"%s\" row "UUID_FMT
546 " (inserted within this transaction) contained "
547 "all-zeros UUID (probably as the default value for "
548 "this column) but deleting this value caused a "
549 "constraint volation because this column is not "
550 "allowed to be empty.", column->name,
551 table->schema->name, UUID_ARGS(row_uuid));
554 "constraint violation",
555 "Deletion of %u weak reference(s) to deleted (or "
556 "never-existing) rows from column \"%s\" in \"%s\" "
557 "row "UUID_FMT" %scaused this column to become empty, "
558 "but constraints on this column disallow an "
560 orig_n - datum->n, column->name, table->schema->name,
564 : "(inserted within this transaction) "));
573 static struct ovsdb_error * WARN_UNUSED_RESULT
574 determine_changes(struct ovsdb_txn *txn, struct ovsdb_txn_row *txn_row)
576 struct ovsdb_table *table = txn_row->table;
578 if (txn_row->old && txn_row->new) {
579 struct shash_node *node;
580 bool changed = false;
582 SHASH_FOR_EACH (node, &table->schema->columns) {
583 const struct ovsdb_column *column = node->data;
584 const struct ovsdb_type *type = &column->type;
585 unsigned int idx = column->index;
587 if (!ovsdb_datum_equals(&txn_row->old->fields[idx],
588 &txn_row->new->fields[idx],
590 bitmap_set1(txn_row->changed, idx);
596 /* Nothing actually changed in this row, so drop it. */
597 ovsdb_txn_row_abort(txn, txn_row);
600 bitmap_set_multiple(txn_row->changed, 0,
601 shash_count(&table->schema->columns), 1);
607 static struct ovsdb_error * WARN_UNUSED_RESULT
608 check_max_rows(struct ovsdb_txn *txn)
610 struct ovsdb_txn_table *t;
612 LIST_FOR_EACH (t, node, &txn->txn_tables) {
613 size_t n_rows = hmap_count(&t->table->rows);
614 unsigned int max_rows = t->table->schema->max_rows;
616 if (n_rows > max_rows) {
617 return ovsdb_error("constraint violation",
618 "transaction causes \"%s\" table to contain "
619 "%zu rows, greater than the schema-defined "
620 "limit of %u row(s)",
621 t->table->schema->name, n_rows, max_rows);
628 static struct ovsdb_row *
629 ovsdb_index_search(struct hmap *index, struct ovsdb_row *row, size_t i,
632 const struct ovsdb_table *table = row->table;
633 const struct ovsdb_column_set *columns = &table->schema->indexes[i];
634 struct hmap_node *node;
636 for (node = hmap_first_with_hash(index, hash); node;
637 node = hmap_next_with_hash(node)) {
638 struct ovsdb_row *irow = ovsdb_row_from_index_node(node, table, i);
639 if (ovsdb_row_equal_columns(row, irow, columns)) {
648 duplicate_index_row__(const struct ovsdb_column_set *index,
649 const struct ovsdb_row *row,
653 size_t n_columns = shash_count(&row->table->schema->columns);
655 ds_put_format(out, "%s row, with UUID "UUID_FMT", ",
656 title, UUID_ARGS(ovsdb_row_get_uuid(row)));
658 || bitmap_scan(row->txn_row->changed, 0, n_columns) == n_columns) {
659 ds_put_cstr(out, "existed in the database before this "
660 "transaction and was not modified by the transaction.");
661 } else if (!row->txn_row->old) {
662 ds_put_cstr(out, "was inserted by this transaction.");
663 } else if (ovsdb_row_equal_columns(row->txn_row->old,
664 row->txn_row->new, index)) {
665 ds_put_cstr(out, "existed in the database before this "
666 "transaction, which modified some of the row's columns "
667 "but not any columns in this index.");
669 ds_put_cstr(out, "had the following index values before the "
671 ovsdb_row_columns_to_string(row->txn_row->old, index, out);
672 ds_put_char(out, '.');
676 static struct ovsdb_error * WARN_UNUSED_RESULT
677 duplicate_index_row(const struct ovsdb_column_set *index,
678 const struct ovsdb_row *a,
679 const struct ovsdb_row *b)
681 struct ovsdb_column_set all_columns;
682 struct ovsdb_error *error;
686 /* Put 'a' and 'b' in a predictable order to make error messages
687 * reproducible for testing. */
688 ovsdb_column_set_init(&all_columns);
689 ovsdb_column_set_add_all(&all_columns, a->table);
690 if (ovsdb_row_compare_columns_3way(a, b, &all_columns) < 0) {
691 const struct ovsdb_row *tmp = a;
695 ovsdb_column_set_destroy(&all_columns);
697 index_s = ovsdb_column_set_to_string(index);
700 ds_put_format(&s, "Transaction causes multiple rows in \"%s\" table to "
701 "have identical values (", a->table->schema->name);
702 ovsdb_row_columns_to_string(a, index, &s);
703 ds_put_format(&s, ") for index on %s. ", index_s);
704 duplicate_index_row__(index, a, "First", &s);
705 ds_put_cstr(&s, " ");
706 duplicate_index_row__(index, b, "Second", &s);
710 error = ovsdb_error("constraint violation", "%s", ds_cstr(&s));
715 static struct ovsdb_error * WARN_UNUSED_RESULT
716 check_index_uniqueness(struct ovsdb_txn *txn OVS_UNUSED,
717 struct ovsdb_txn_row *txn_row)
719 struct ovsdb_txn_table *txn_table = txn_row->table->txn_table;
720 struct ovsdb_table *table = txn_row->table;
721 struct ovsdb_row *row = txn_row->new;
728 for (i = 0; i < table->schema->n_indexes; i++) {
729 const struct ovsdb_column_set *index = &table->schema->indexes[i];
730 struct ovsdb_row *irow;
733 hash = ovsdb_row_hash_columns(row, index, 0);
734 irow = ovsdb_index_search(&txn_table->txn_indexes[i], row, i, hash);
736 return duplicate_index_row(index, irow, row);
739 irow = ovsdb_index_search(&table->indexes[i], row, i, hash);
740 if (irow && !irow->txn_row) {
741 return duplicate_index_row(index, irow, row);
744 hmap_insert(&txn_table->txn_indexes[i],
745 ovsdb_row_get_index_node(row, i), hash);
752 ovsdb_txn_commit(struct ovsdb_txn *txn, bool durable)
754 struct ovsdb_replica *replica;
755 struct ovsdb_error *error;
757 /* Figure out what actually changed, and abort early if the transaction
758 * was really a no-op. */
759 error = for_each_txn_row(txn, determine_changes);
761 return OVSDB_WRAP_BUG("can't happen", error);
763 if (list_is_empty(&txn->txn_tables)) {
764 ovsdb_txn_abort(txn);
768 /* Update reference counts and check referential integrity. */
769 error = update_ref_counts(txn);
771 ovsdb_txn_abort(txn);
775 /* Delete unreferenced, non-root rows. */
776 error = for_each_txn_row(txn, collect_garbage);
778 ovsdb_txn_abort(txn);
779 return OVSDB_WRAP_BUG("can't happen", error);
782 /* Check maximum rows table constraints. */
783 error = check_max_rows(txn);
785 ovsdb_txn_abort(txn);
789 /* Check reference counts and remove bad references for "weak" referential
791 error = for_each_txn_row(txn, assess_weak_refs);
793 ovsdb_txn_abort(txn);
797 /* Verify that the indexes will still be unique post-transaction. */
798 error = for_each_txn_row(txn, check_index_uniqueness);
800 ovsdb_txn_abort(txn);
804 /* Send the commit to each replica. */
805 LIST_FOR_EACH (replica, node, &txn->db->replicas) {
806 error = (replica->class->commit)(replica, txn, durable);
808 /* We don't support two-phase commit so only the first replica is
809 * allowed to report an error. */
810 assert(&replica->node == txn->db->replicas.next);
812 ovsdb_txn_abort(txn);
817 /* Finalize commit. */
818 txn->db->run_triggers = true;
819 ovsdb_error_assert(for_each_txn_row(txn, ovsdb_txn_row_commit));
826 ovsdb_txn_for_each_change(const struct ovsdb_txn *txn,
827 ovsdb_txn_row_cb_func *cb, void *aux)
829 struct ovsdb_txn_table *t;
830 struct ovsdb_txn_row *r;
832 LIST_FOR_EACH (t, node, &txn->txn_tables) {
833 HMAP_FOR_EACH (r, hmap_node, &t->txn_rows) {
834 if ((r->old || r->new) && !cb(r->old, r->new, r->changed, aux)) {
841 static struct ovsdb_txn_table *
842 ovsdb_txn_create_txn_table(struct ovsdb_txn *txn, struct ovsdb_table *table)
844 if (!table->txn_table) {
845 struct ovsdb_txn_table *txn_table;
848 table->txn_table = txn_table = xmalloc(sizeof *table->txn_table);
849 txn_table->table = table;
850 hmap_init(&txn_table->txn_rows);
851 txn_table->serial = serial - 1;
852 txn_table->txn_indexes = xmalloc(table->schema->n_indexes
853 * sizeof *txn_table->txn_indexes);
854 for (i = 0; i < table->schema->n_indexes; i++) {
855 hmap_init(&txn_table->txn_indexes[i]);
857 list_push_back(&txn->txn_tables, &txn_table->node);
859 return table->txn_table;
862 static struct ovsdb_txn_row *
863 ovsdb_txn_row_create(struct ovsdb_txn *txn, struct ovsdb_table *table,
864 const struct ovsdb_row *old_, struct ovsdb_row *new)
866 const struct ovsdb_row *row = old_ ? old_ : new;
867 struct ovsdb_row *old = (struct ovsdb_row *) old_;
868 size_t n_columns = shash_count(&table->schema->columns);
869 struct ovsdb_txn_table *txn_table;
870 struct ovsdb_txn_row *txn_row;
872 txn_row = xzalloc(offsetof(struct ovsdb_txn_row, changed)
873 + bitmap_n_bytes(n_columns));
874 txn_row->uuid = *ovsdb_row_get_uuid(row);
875 txn_row->table = row->table;
878 txn_row->n_refs = old ? old->n_refs : 0;
879 txn_row->serial = serial - 1;
882 old->txn_row = txn_row;
885 new->txn_row = txn_row;
888 txn_table = ovsdb_txn_create_txn_table(txn, table);
889 hmap_insert(&txn_table->txn_rows, &txn_row->hmap_node,
890 ovsdb_row_hash(old ? old : new));
896 ovsdb_txn_row_modify(struct ovsdb_txn *txn, const struct ovsdb_row *ro_row_)
898 struct ovsdb_row *ro_row = (struct ovsdb_row *) ro_row_;
900 if (ro_row->txn_row) {
901 assert(ro_row == ro_row->txn_row->new);
904 struct ovsdb_table *table = ro_row->table;
905 struct ovsdb_row *rw_row;
907 rw_row = ovsdb_row_clone(ro_row);
908 rw_row->n_refs = ro_row->n_refs;
909 uuid_generate(ovsdb_row_get_version_rw(rw_row));
910 ovsdb_txn_row_create(txn, table, ro_row, rw_row);
911 hmap_replace(&table->rows, &ro_row->hmap_node, &rw_row->hmap_node);
918 ovsdb_txn_row_insert(struct ovsdb_txn *txn, struct ovsdb_row *row)
920 uint32_t hash = ovsdb_row_hash(row);
921 struct ovsdb_table *table = row->table;
923 uuid_generate(ovsdb_row_get_version_rw(row));
925 ovsdb_txn_row_create(txn, table, NULL, row);
926 hmap_insert(&table->rows, &row->hmap_node, hash);
929 /* 'row' must be assumed destroyed upon return; the caller must not reference
932 ovsdb_txn_row_delete(struct ovsdb_txn *txn, const struct ovsdb_row *row_)
934 struct ovsdb_row *row = (struct ovsdb_row *) row_;
935 struct ovsdb_table *table = row->table;
936 struct ovsdb_txn_row *txn_row = row->txn_row;
938 hmap_remove(&table->rows, &row->hmap_node);
941 ovsdb_txn_row_create(txn, table, row, NULL);
943 assert(txn_row->new == row);
947 hmap_remove(&table->txn_table->txn_rows, &txn_row->hmap_node);
950 ovsdb_row_destroy(row);
955 ovsdb_txn_add_comment(struct ovsdb_txn *txn, const char *s)
957 if (txn->comment.length) {
958 ds_put_char(&txn->comment, '\n');
960 ds_put_cstr(&txn->comment, s);
964 ovsdb_txn_get_comment(const struct ovsdb_txn *txn)
966 return txn->comment.length ? ds_cstr_ro(&txn->comment) : NULL;
970 ovsdb_txn_row_prefree(struct ovsdb_txn_row *txn_row)
972 struct ovsdb_txn_table *txn_table = txn_row->table->txn_table;
974 txn_table->n_processed--;
975 hmap_remove(&txn_table->txn_rows, &txn_row->hmap_node);
978 txn_row->old->txn_row = NULL;
981 txn_row->new->txn_row = NULL;
986 ovsdb_txn_table_destroy(struct ovsdb_txn_table *txn_table)
990 assert(hmap_is_empty(&txn_table->txn_rows));
992 for (i = 0; i < txn_table->table->schema->n_indexes; i++) {
993 hmap_destroy(&txn_table->txn_indexes[i]);
995 free(txn_table->txn_indexes);
997 txn_table->table->txn_table = NULL;
998 hmap_destroy(&txn_table->txn_rows);
999 list_remove(&txn_table->node);
1003 /* Calls 'cb' for every txn_row within 'txn'. If 'cb' returns nonnull, this
1004 * aborts the iteration and for_each_txn_row() passes the error up. Otherwise,
1005 * returns a null pointer after iteration is complete.
1007 * 'cb' may insert new txn_rows and new txn_tables into 'txn'. It may delete
1008 * the txn_row that it is passed in, or txn_rows in txn_tables other than the
1009 * one passed to 'cb'. It may *not* delete txn_rows other than the one passed
1010 * in within the same txn_table. It may *not* delete any txn_tables. As long
1011 * as these rules are followed, 'cb' will be called exactly once for each
1012 * txn_row in 'txn', even those added by 'cb'.
1014 * (Even though 'cb' is not allowed to delete some txn_rows, it can still
1015 * delete any actual row by clearing a txn_row's 'new' member.)
1017 static struct ovsdb_error * WARN_UNUSED_RESULT
1018 for_each_txn_row(struct ovsdb_txn *txn,
1019 struct ovsdb_error *(*cb)(struct ovsdb_txn *,
1020 struct ovsdb_txn_row *))
1027 struct ovsdb_txn_table *t, *next_txn_table;
1030 LIST_FOR_EACH_SAFE (t, next_txn_table, node, &txn->txn_tables) {
1031 if (t->serial != serial) {
1036 while (t->n_processed < hmap_count(&t->txn_rows)) {
1037 struct ovsdb_txn_row *r, *next_txn_row;
1039 HMAP_FOR_EACH_SAFE (r, next_txn_row, hmap_node, &t->txn_rows) {
1040 if (r->serial != serial) {
1041 struct ovsdb_error *error;
1054 if (hmap_is_empty(&t->txn_rows)) {
1055 /* Table is empty. Drop it. */
1056 ovsdb_txn_table_destroy(t);