-/* Copyright (c) 2009, 2010 Nicira Networks
+/* Copyright (c) 2009, 2010, 2011 Nicira Networks
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
*
* - 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,
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;
}
- HMAP_FOR_EACH_WITH_HASH (txn_row, struct ovsdb_txn_row, hmap_node,
+ 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,
+ovsdb_txn_adjust_atom_refs(struct ovsdb_txn *txn, const struct ovsdb_row *r,
+ const struct ovsdb_column *c,
const struct ovsdb_base_type *base,
const union ovsdb_atom *atoms, unsigned int n,
int delta)
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",
- "reference to nonexistent row "
- UUID_FMT, UUID_ARGS(uuid));
- }
+ 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;
}
const struct ovsdb_datum *field = &r->fields[column->index];
struct ovsdb_error *error;
- error = ovsdb_txn_adjust_atom_refs(txn, &column->type.key,
+ error = ovsdb_txn_adjust_atom_refs(txn, r, column, &column->type.key,
field->keys, field->n, delta);
if (!error) {
- error = ovsdb_txn_adjust_atom_refs(txn, &column->type.value,
+ error = ovsdb_txn_adjust_atom_refs(txn, r, column, &column->type.value,
field->values, field->n, delta);
}
return error;
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) {
if (r->old) {
error = ovsdb_txn_adjust_row_refs(txn, r->old, column, -1);
if (error) {
- ovsdb_error_destroy(error);
- return OVSDB_BUG("error decreasing refcount");
+ return OVSDB_WRAP_BUG("error decreasing refcount", error);
}
}
if (r->new) {
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)
{
* that their weak references will get reassessed. */
struct ovsdb_weak_ref *weak, *next;
- LIST_FOR_EACH_SAFE (weak, next, struct ovsdb_weak_ref, dst_node,
- &txn_row->old->dst_refs) {
+ LIST_FOR_EACH_SAFE (weak, next, dst_node, &txn_row->old->dst_refs) {
if (!weak->src->txn_row) {
ovsdb_txn_row_modify(txn, weak->src);
}
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_error * WARN_UNUSED_RESULT
+check_max_rows(struct ovsdb_txn *txn)
+{
+ struct ovsdb_txn_table *t;
+
+ LIST_FOR_EACH (t, node, &txn->txn_tables) {
+ size_t n_rows = hmap_count(&t->table->rows);
+ unsigned int max_rows = t->table->schema->max_rows;
+
+ if (n_rows > max_rows) {
+ return ovsdb_error("constraint violation",
+ "transaction causes \"%s\" table to contain "
+ "%zu rows, greater than the schema-defined "
+ "limit of %u row(s)",
+ t->table->schema->name, n_rows, max_rows);
+ }
+ }
+
+ return NULL;
+}
+
struct ovsdb_error *
ovsdb_txn_commit(struct ovsdb_txn *txn, bool durable)
{
* was really a no-op. */
error = for_each_txn_row(txn, determine_changes);
if (error) {
- ovsdb_error_destroy(error);
- return OVSDB_BUG("can't happen");
+ return OVSDB_WRAP_BUG("can't happen", error);
}
if (list_is_empty(&txn->txn_tables)) {
ovsdb_txn_abort(txn);
return error;
}
+ /* 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
* integrity. */
error = for_each_txn_row(txn, assess_weak_refs);
}
/* Send the commit to each replica. */
- LIST_FOR_EACH (replica, struct ovsdb_replica, node, &txn->db->replicas) {
+ 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
struct ovsdb_txn_table *t;
struct ovsdb_txn_row *r;
- LIST_FOR_EACH (t, struct ovsdb_txn_table, node, &txn->txn_tables) {
- HMAP_FOR_EACH (r, struct ovsdb_txn_row, hmap_node, &t->txn_rows) {
- if (!cb(r->old, r->new, r->changed, aux)) {
+ LIST_FOR_EACH (t, node, &txn->txn_tables) {
+ HMAP_FOR_EACH (r, hmap_node, &t->txn_rows) {
+ if ((r->old || r->new) && !cb(r->old, r->new, r->changed, aux)) {
break;
}
}
ovsdb_txn_row_create(struct ovsdb_txn *txn, struct ovsdb_table *table,
const struct ovsdb_row *old_, struct ovsdb_row *new)
{
+ const struct ovsdb_row *row = old_ ? old_ : new;
struct ovsdb_row *old = (struct ovsdb_row *) old_;
size_t n_columns = shash_count(&table->schema->columns);
struct ovsdb_txn_table *txn_table;
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;
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);
* 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,
struct ovsdb_txn_table *t, *next_txn_table;
any_work = false;
- LIST_FOR_EACH_SAFE (t, next_txn_table, struct ovsdb_txn_table, node,
- &txn->txn_tables) {
+ LIST_FOR_EACH_SAFE (t, next_txn_table, node, &txn->txn_tables) {
if (t->serial != serial) {
t->serial = serial;
t->n_processed = 0;
while (t->n_processed < hmap_count(&t->txn_rows)) {
struct ovsdb_txn_row *r, *next_txn_row;
- HMAP_FOR_EACH_SAFE (r, next_txn_row,
- struct ovsdb_txn_row, hmap_node,
- &t->txn_rows) {
+ HMAP_FOR_EACH_SAFE (r, next_txn_row, hmap_node, &t->txn_rows) {
if (r->serial != serial) {
struct ovsdb_error *error;