-/* Copyright (c) 2009, 2010, 2011 Nicira Networks
+/* Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include "transaction.h"
-#include <assert.h>
-
#include "bitmap.h"
#include "dynamic-string.h"
#include "hash.h"
struct ovsdb_table *table;
struct hmap txn_rows; /* Contains "struct ovsdb_txn_row"s. */
+ /* This has the same form as the 'indexes' member of struct ovsdb_table,
+ * but it is only used or updated at transaction commit time, from
+ * check_index_uniqueness(). */
+ struct hmap *txn_indexes;
+
/* Used by for_each_txn_row(). */
unsigned int serial; /* Serial number of in-progress iteration. */
unsigned int n_processed; /* Number of rows processed. */
*
* - A row modified by a transaction will have non-null 'old' and 'new'.
*
- * - 'old' and 'new' both null is invalid. It would indicate that a row
- * was added then deleted within a single transaction, but we instead
- * handle that case by deleting the txn_row entirely.
+ * - 'old' and 'new' both null indicates that a row was added then deleted
+ * within a single transaction. Most of the time we instead delete the
+ * ovsdb_txn_row entirely, but inside a for_each_txn_row() callback
+ * there are restrictions that sometimes mean we have to leave the
+ * ovsdb_txn_row in place.
*/
struct ovsdb_txn_row {
struct hmap_node hmap_node; /* In ovsdb_txn_table's txn_rows hmap. */
struct ovsdb_row *new; /* The new row. */
size_t n_refs; /* Number of remaining references. */
+ /* These members are the same as the corresponding members of 'old' or
+ * 'new'. They are present here for convenience and because occasionally
+ * there can be an ovsdb_txn_row where both 'old' and 'new' are NULL. */
+ struct uuid uuid;
+ struct ovsdb_table *table;
+
/* Used by for_each_txn_row(). */
unsigned int serial; /* Serial number of in-progress commit. */
unsigned long changed[]; /* Bits set to 1 for columns that changed. */
};
+static struct ovsdb_error * WARN_UNUSED_RESULT
+delete_garbage_row(struct ovsdb_txn *txn, struct ovsdb_txn_row *r);
static void ovsdb_txn_row_prefree(struct ovsdb_txn_row *);
static struct ovsdb_error * WARN_UNUSED_RESULT
for_each_txn_row(struct ovsdb_txn *txn,
static void
ovsdb_txn_free(struct ovsdb_txn *txn)
{
- assert(list_is_empty(&txn->txn_tables));
+ ovs_assert(list_is_empty(&txn->txn_tables));
ds_destroy(&txn->comment);
free(txn);
}
ovsdb_txn_row_prefree(txn_row);
if (!old) {
- hmap_remove(&new->table->rows, &new->hmap_node);
+ if (new) {
+ hmap_remove(&new->table->rows, &new->hmap_node);
+ }
} else if (!new) {
hmap_insert(&old->table->rows, &old->hmap_node, ovsdb_row_hash(old));
} else {
return NULL;
}
+/* Returns the offset in bytes from the start of an ovsdb_row for 'table' to
+ * the hmap_node for the index numbered 'i'. */
+static size_t
+ovsdb_row_index_offset__(const struct ovsdb_table *table, size_t i)
+{
+ size_t n_fields = shash_count(&table->schema->columns);
+ return (offsetof(struct ovsdb_row, fields)
+ + n_fields * sizeof(struct ovsdb_datum)
+ + i * sizeof(struct hmap_node));
+}
+
+/* Returns the hmap_node in 'row' for the index numbered 'i'. */
+static struct hmap_node *
+ovsdb_row_get_index_node(struct ovsdb_row *row, size_t i)
+{
+ return (void *) ((char *) row + ovsdb_row_index_offset__(row->table, i));
+}
+
+/* Returns the ovsdb_row given 'index_node', which is a pointer to that row's
+ * hmap_node for the index numbered 'i' within 'table'. */
+static struct ovsdb_row *
+ovsdb_row_from_index_node(struct hmap_node *index_node,
+ const struct ovsdb_table *table, size_t i)
+{
+ return (void *) ((char *) index_node - ovsdb_row_index_offset__(table, i));
+}
+
void
ovsdb_txn_abort(struct ovsdb_txn *txn)
{
HMAP_FOR_EACH_WITH_HASH (txn_row, hmap_node,
uuid_hash(uuid), &table->txn_table->txn_rows) {
- const struct ovsdb_row *row;
-
- row = txn_row->old ? txn_row->old : txn_row->new;
- if (uuid_equals(uuid, ovsdb_row_get_uuid(row))) {
+ if (uuid_equals(uuid, &txn_row->uuid)) {
return txn_row;
}
}
return NULL;
}
+static struct ovsdb_txn_row *
+find_or_make_txn_row(struct ovsdb_txn *txn, const struct ovsdb_table *table,
+ const struct uuid *uuid)
+{
+ struct ovsdb_txn_row *txn_row = find_txn_row(table, uuid);
+ if (!txn_row) {
+ const struct ovsdb_row *row = ovsdb_table_get_row(table, uuid);
+ if (row) {
+ txn_row = ovsdb_txn_row_modify(txn, row)->txn_row;
+ }
+ }
+ return txn_row;
+}
+
static struct ovsdb_error * WARN_UNUSED_RESULT
ovsdb_txn_adjust_atom_refs(struct ovsdb_txn *txn, const struct ovsdb_row *r,
const struct ovsdb_column *c,
table = base->u.uuid.refTable;
for (i = 0; i < n; i++) {
const struct uuid *uuid = &atoms[i].uuid;
- struct ovsdb_txn_row *txn_row = find_txn_row(table, uuid);
+ struct ovsdb_txn_row *txn_row;
+
+ if (uuid_equals(uuid, ovsdb_row_get_uuid(r))) {
+ /* Self-references don't count. */
+ continue;
+ }
+
+ txn_row = find_or_make_txn_row(txn, table, uuid);
if (!txn_row) {
- const struct ovsdb_row *row = ovsdb_table_get_row(table, uuid);
- if (row) {
- txn_row = ovsdb_txn_row_modify(txn, row)->txn_row;
- } else {
- return ovsdb_error("referential integrity violation",
- "Table %s column %s row "UUID_FMT" "
- "references nonexistent row "UUID_FMT" in "
- "table %s.",
- r->table->schema->name, c->name,
- UUID_ARGS(ovsdb_row_get_uuid(r)),
- UUID_ARGS(uuid), table->schema->name);
- }
+ return ovsdb_error("referential integrity violation",
+ "Table %s column %s row "UUID_FMT" "
+ "references nonexistent row "UUID_FMT" in "
+ "table %s.",
+ r->table->schema->name, c->name,
+ UUID_ARGS(ovsdb_row_get_uuid(r)),
+ UUID_ARGS(uuid), table->schema->name);
}
txn_row->n_refs += delta;
}
static struct ovsdb_error * WARN_UNUSED_RESULT
update_row_ref_count(struct ovsdb_txn *txn, struct ovsdb_txn_row *r)
{
- struct ovsdb_table *table = r->old ? r->old->table : r->new->table;
+ struct ovsdb_table *table = r->table;
struct shash_node *node;
SHASH_FOR_EACH (node, &table->schema->columns) {
return ovsdb_error("referential integrity violation",
"cannot delete %s row "UUID_FMT" because "
"of %zu remaining reference(s)",
- r->old->table->schema->name,
- UUID_ARGS(ovsdb_row_get_uuid(r->old)),
+ r->table->schema->name, UUID_ARGS(&r->uuid),
r->n_refs);
}
}
+static struct ovsdb_error * WARN_UNUSED_RESULT
+delete_row_refs(struct ovsdb_txn *txn, const struct ovsdb_row *row,
+ const struct ovsdb_base_type *base,
+ const union ovsdb_atom *atoms, unsigned int n)
+{
+ const struct ovsdb_table *table;
+ unsigned int i;
+
+ if (!ovsdb_base_type_is_strong_ref(base)) {
+ return NULL;
+ }
+
+ table = base->u.uuid.refTable;
+ for (i = 0; i < n; i++) {
+ const struct uuid *uuid = &atoms[i].uuid;
+ struct ovsdb_txn_row *txn_row;
+
+ if (uuid_equals(uuid, ovsdb_row_get_uuid(row))) {
+ /* Self-references don't count. */
+ continue;
+ }
+
+ txn_row = find_or_make_txn_row(txn, table, uuid);
+ if (!txn_row) {
+ return OVSDB_BUG("strong ref target missing");
+ } else if (!txn_row->n_refs) {
+ return OVSDB_BUG("strong ref target has zero n_refs");
+ } else if (!txn_row->new) {
+ return OVSDB_BUG("deleted strong ref target");
+ }
+
+ if (--txn_row->n_refs == 0) {
+ struct ovsdb_error *error = delete_garbage_row(txn, txn_row);
+ if (error) {
+ return error;
+ }
+ }
+ }
+
+ return NULL;
+}
+
+static struct ovsdb_error * WARN_UNUSED_RESULT
+delete_garbage_row(struct ovsdb_txn *txn, struct ovsdb_txn_row *txn_row)
+{
+ struct shash_node *node;
+ struct ovsdb_row *row;
+
+ if (txn_row->table->schema->is_root) {
+ return NULL;
+ }
+
+ row = txn_row->new;
+ txn_row->new = NULL;
+ hmap_remove(&txn_row->table->rows, &row->hmap_node);
+ SHASH_FOR_EACH (node, &txn_row->table->schema->columns) {
+ const struct ovsdb_column *column = node->data;
+ const struct ovsdb_datum *field = &row->fields[column->index];
+ struct ovsdb_error *error;
+
+ error = delete_row_refs(txn, row,
+ &column->type.key, field->keys, field->n);
+ if (error) {
+ return error;
+ }
+
+ error = delete_row_refs(txn, row,
+ &column->type.value, field->values, field->n);
+ if (error) {
+ return error;
+ }
+ }
+ ovsdb_row_destroy(row);
+
+ return NULL;
+}
+
+static struct ovsdb_error * WARN_UNUSED_RESULT
+collect_garbage(struct ovsdb_txn *txn, struct ovsdb_txn_row *txn_row)
+{
+ if (txn_row->new && !txn_row->n_refs) {
+ return delete_garbage_row(txn, txn_row);
+ }
+ return NULL;
+}
+
static struct ovsdb_error * WARN_UNUSED_RESULT
update_ref_counts(struct ovsdb_txn *txn)
{
ovsdb_txn_row_commit(struct ovsdb_txn *txn OVS_UNUSED,
struct ovsdb_txn_row *txn_row)
{
+ size_t n_indexes = txn_row->table->schema->n_indexes;
+
+ if (txn_row->old) {
+ size_t i;
+
+ for (i = 0; i < n_indexes; i++) {
+ struct hmap_node *node = ovsdb_row_get_index_node(txn_row->old, i);
+ hmap_remove(&txn_row->table->indexes[i], node);
+ }
+ }
+ if (txn_row->new) {
+ size_t i;
+
+ for (i = 0; i < n_indexes; i++) {
+ struct hmap_node *node = ovsdb_row_get_index_node(txn_row->new, i);
+ hmap_insert(&txn_row->table->indexes[i], node, node->hash);
+ }
+ }
+
ovsdb_txn_row_prefree(txn_row);
if (txn_row->new) {
txn_row->new->n_refs = txn_row->n_refs;
add_weak_ref(struct ovsdb_txn *txn,
const struct ovsdb_row *src_, const struct ovsdb_row *dst_)
{
- struct ovsdb_row *src = (struct ovsdb_row *) src_;
- struct ovsdb_row *dst = (struct ovsdb_row *) dst_;
+ struct ovsdb_row *src = CONST_CAST(struct ovsdb_row *, src_);
+ struct ovsdb_row *dst = CONST_CAST(struct ovsdb_row *, dst_);
struct ovsdb_weak_ref *weak;
if (src == dst) {
return NULL;
}
- table = txn_row->new->table;
+ table = txn_row->table;
SHASH_FOR_EACH (node, &table->schema->columns) {
const struct ovsdb_column *column = node->data;
struct ovsdb_datum *datum = &txn_row->new->fields[column->index];
static struct ovsdb_error * WARN_UNUSED_RESULT
determine_changes(struct ovsdb_txn *txn, struct ovsdb_txn_row *txn_row)
{
- struct ovsdb_table *table;
+ struct ovsdb_table *table = txn_row->table;
- table = (txn_row->old ? txn_row->old : txn_row->new)->table;
if (txn_row->old && txn_row->new) {
struct shash_node *node;
bool changed = false;
return NULL;
}
+static struct ovsdb_row *
+ovsdb_index_search(struct hmap *index, struct ovsdb_row *row, size_t i,
+ uint32_t hash)
+{
+ const struct ovsdb_table *table = row->table;
+ const struct ovsdb_column_set *columns = &table->schema->indexes[i];
+ struct hmap_node *node;
+
+ for (node = hmap_first_with_hash(index, hash); node;
+ node = hmap_next_with_hash(node)) {
+ struct ovsdb_row *irow = ovsdb_row_from_index_node(node, table, i);
+ if (ovsdb_row_equal_columns(row, irow, columns)) {
+ return irow;
+ }
+ }
+
+ return NULL;
+}
+
+static void
+duplicate_index_row__(const struct ovsdb_column_set *index,
+ const struct ovsdb_row *row,
+ const char *title,
+ struct ds *out)
+{
+ size_t n_columns = shash_count(&row->table->schema->columns);
+
+ ds_put_format(out, "%s row, with UUID "UUID_FMT", ",
+ title, UUID_ARGS(ovsdb_row_get_uuid(row)));
+ if (!row->txn_row
+ || bitmap_scan(row->txn_row->changed, 0, n_columns) == n_columns) {
+ ds_put_cstr(out, "existed in the database before this "
+ "transaction and was not modified by the transaction.");
+ } else if (!row->txn_row->old) {
+ ds_put_cstr(out, "was inserted by this transaction.");
+ } else if (ovsdb_row_equal_columns(row->txn_row->old,
+ row->txn_row->new, index)) {
+ ds_put_cstr(out, "existed in the database before this "
+ "transaction, which modified some of the row's columns "
+ "but not any columns in this index.");
+ } else {
+ ds_put_cstr(out, "had the following index values before the "
+ "transaction: ");
+ ovsdb_row_columns_to_string(row->txn_row->old, index, out);
+ ds_put_char(out, '.');
+ }
+}
+
+static struct ovsdb_error * WARN_UNUSED_RESULT
+duplicate_index_row(const struct ovsdb_column_set *index,
+ const struct ovsdb_row *a,
+ const struct ovsdb_row *b)
+{
+ struct ovsdb_column_set all_columns;
+ struct ovsdb_error *error;
+ char *index_s;
+ struct ds s;
+
+ /* Put 'a' and 'b' in a predictable order to make error messages
+ * reproducible for testing. */
+ ovsdb_column_set_init(&all_columns);
+ ovsdb_column_set_add_all(&all_columns, a->table);
+ if (ovsdb_row_compare_columns_3way(a, b, &all_columns) < 0) {
+ const struct ovsdb_row *tmp = a;
+ a = b;
+ b = tmp;
+ }
+ ovsdb_column_set_destroy(&all_columns);
+
+ index_s = ovsdb_column_set_to_string(index);
+
+ ds_init(&s);
+ ds_put_format(&s, "Transaction causes multiple rows in \"%s\" table to "
+ "have identical values (", a->table->schema->name);
+ ovsdb_row_columns_to_string(a, index, &s);
+ ds_put_format(&s, ") for index on %s. ", index_s);
+ duplicate_index_row__(index, a, "First", &s);
+ ds_put_cstr(&s, " ");
+ duplicate_index_row__(index, b, "Second", &s);
+
+ free(index_s);
+
+ error = ovsdb_error("constraint violation", "%s", ds_cstr(&s));
+ ds_destroy(&s);
+ return error;
+}
+
+static struct ovsdb_error * WARN_UNUSED_RESULT
+check_index_uniqueness(struct ovsdb_txn *txn OVS_UNUSED,
+ struct ovsdb_txn_row *txn_row)
+{
+ struct ovsdb_txn_table *txn_table = txn_row->table->txn_table;
+ struct ovsdb_table *table = txn_row->table;
+ struct ovsdb_row *row = txn_row->new;
+ size_t i;
+
+ if (!row) {
+ return NULL;
+ }
+
+ for (i = 0; i < table->schema->n_indexes; i++) {
+ const struct ovsdb_column_set *index = &table->schema->indexes[i];
+ struct ovsdb_row *irow;
+ uint32_t hash;
+
+ hash = ovsdb_row_hash_columns(row, index, 0);
+ irow = ovsdb_index_search(&txn_table->txn_indexes[i], row, i, hash);
+ if (irow) {
+ return duplicate_index_row(index, irow, row);
+ }
+
+ irow = ovsdb_index_search(&table->indexes[i], row, i, hash);
+ if (irow && !irow->txn_row) {
+ return duplicate_index_row(index, irow, row);
+ }
+
+ hmap_insert(&txn_table->txn_indexes[i],
+ ovsdb_row_get_index_node(row, i), hash);
+ }
+
+ return NULL;
+}
+
struct ovsdb_error *
ovsdb_txn_commit(struct ovsdb_txn *txn, bool durable)
{
return NULL;
}
- /* Check maximum rows table constraints. */
- error = check_max_rows(txn);
+ /* Update reference counts and check referential integrity. */
+ error = update_ref_counts(txn);
if (error) {
ovsdb_txn_abort(txn);
return error;
}
- /* Update reference counts and check referential integrity. */
- error = update_ref_counts(txn);
+ /* Delete unreferenced, non-root rows. */
+ error = for_each_txn_row(txn, collect_garbage);
+ if (error) {
+ ovsdb_txn_abort(txn);
+ return OVSDB_WRAP_BUG("can't happen", error);
+ }
+
+ /* Check maximum rows table constraints. */
+ error = check_max_rows(txn);
if (error) {
ovsdb_txn_abort(txn);
return error;
}
- /* Check reference counts and remove bad reference for "weak" referential
+ /* Check reference counts and remove bad references for "weak" referential
* integrity. */
error = for_each_txn_row(txn, assess_weak_refs);
if (error) {
return error;
}
+ /* Verify that the indexes will still be unique post-transaction. */
+ error = for_each_txn_row(txn, check_index_uniqueness);
+ if (error) {
+ ovsdb_txn_abort(txn);
+ return error;
+ }
+
/* Send the commit to each replica. */
LIST_FOR_EACH (replica, node, &txn->db->replicas) {
error = (replica->class->commit)(replica, txn, durable);
if (error) {
/* We don't support two-phase commit so only the first replica is
* allowed to report an error. */
- assert(&replica->node == txn->db->replicas.next);
+ ovs_assert(&replica->node == txn->db->replicas.next);
ovsdb_txn_abort(txn);
return error;
LIST_FOR_EACH (t, node, &txn->txn_tables) {
HMAP_FOR_EACH (r, hmap_node, &t->txn_rows) {
- if (!cb(r->old, r->new, r->changed, aux)) {
+ if ((r->old || r->new) && !cb(r->old, r->new, r->changed, aux)) {
break;
}
}
{
if (!table->txn_table) {
struct ovsdb_txn_table *txn_table;
+ size_t i;
table->txn_table = txn_table = xmalloc(sizeof *table->txn_table);
txn_table->table = table;
hmap_init(&txn_table->txn_rows);
txn_table->serial = serial - 1;
+ txn_table->txn_indexes = xmalloc(table->schema->n_indexes
+ * sizeof *txn_table->txn_indexes);
+ for (i = 0; i < table->schema->n_indexes; i++) {
+ hmap_init(&txn_table->txn_indexes[i]);
+ }
list_push_back(&txn->txn_tables, &txn_table->node);
}
return table->txn_table;
ovsdb_txn_row_create(struct ovsdb_txn *txn, struct ovsdb_table *table,
const struct ovsdb_row *old_, struct ovsdb_row *new)
{
- struct ovsdb_row *old = (struct ovsdb_row *) old_;
+ const struct ovsdb_row *row = old_ ? old_ : new;
+ struct ovsdb_row *old = CONST_CAST(struct ovsdb_row *, old_);
size_t n_columns = shash_count(&table->schema->columns);
struct ovsdb_txn_table *txn_table;
struct ovsdb_txn_row *txn_row;
txn_row = xzalloc(offsetof(struct ovsdb_txn_row, changed)
+ bitmap_n_bytes(n_columns));
- txn_row->old = (struct ovsdb_row *) old;
+ txn_row->uuid = *ovsdb_row_get_uuid(row);
+ txn_row->table = row->table;
+ txn_row->old = old;
txn_row->new = new;
txn_row->n_refs = old ? old->n_refs : 0;
txn_row->serial = serial - 1;
struct ovsdb_row *
ovsdb_txn_row_modify(struct ovsdb_txn *txn, const struct ovsdb_row *ro_row_)
{
- struct ovsdb_row *ro_row = (struct ovsdb_row *) ro_row_;
+ struct ovsdb_row *ro_row = CONST_CAST(struct ovsdb_row *, ro_row_);
if (ro_row->txn_row) {
- assert(ro_row == ro_row->txn_row->new);
+ ovs_assert(ro_row == ro_row->txn_row->new);
return ro_row;
} else {
struct ovsdb_table *table = ro_row->table;
void
ovsdb_txn_row_delete(struct ovsdb_txn *txn, const struct ovsdb_row *row_)
{
- struct ovsdb_row *row = (struct ovsdb_row *) row_;
+ struct ovsdb_row *row = CONST_CAST(struct ovsdb_row *, row_);
struct ovsdb_table *table = row->table;
struct ovsdb_txn_row *txn_row = row->txn_row;
if (!txn_row) {
ovsdb_txn_row_create(txn, table, row, NULL);
} else {
- assert(txn_row->new == row);
+ ovs_assert(txn_row->new == row);
if (txn_row->old) {
txn_row->new = NULL;
} else {
static void
ovsdb_txn_row_prefree(struct ovsdb_txn_row *txn_row)
{
- struct ovsdb_row *row = txn_row->old ? txn_row->old : txn_row->new;
- struct ovsdb_txn_table *txn_table = row->table->txn_table;
+ struct ovsdb_txn_table *txn_table = txn_row->table->txn_table;
txn_table->n_processed--;
hmap_remove(&txn_table->txn_rows, &txn_row->hmap_node);
static void
ovsdb_txn_table_destroy(struct ovsdb_txn_table *txn_table)
{
- assert(hmap_is_empty(&txn_table->txn_rows));
+ size_t i;
+
+ ovs_assert(hmap_is_empty(&txn_table->txn_rows));
+
+ for (i = 0; i < txn_table->table->schema->n_indexes; i++) {
+ hmap_destroy(&txn_table->txn_indexes[i]);
+ }
+ free(txn_table->txn_indexes);
+
txn_table->table->txn_table = NULL;
hmap_destroy(&txn_table->txn_rows);
list_remove(&txn_table->node);
* in within the same txn_table. It may *not* delete any txn_tables. As long
* as these rules are followed, 'cb' will be called exactly once for each
* txn_row in 'txn', even those added by 'cb'.
+ *
+ * (Even though 'cb' is not allowed to delete some txn_rows, it can still
+ * delete any actual row by clearing a txn_row's 'new' member.)
*/
static struct ovsdb_error * WARN_UNUSED_RESULT
for_each_txn_row(struct ovsdb_txn *txn,