X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fovsdb-idl.c;h=46cc51ee70e3ffb06e177996fe87253ff1d7bbbf;hb=d98e60075528c3065ad453f7add4b30f22edcde3;hp=42c53b831c60e9044731af6dd4cdedb69ba46b38;hpb=a0bc29a541fc7dc6e20137d5558e2094d614e6ab;p=sliver-openvswitch.git diff --git a/lib/ovsdb-idl.c b/lib/ovsdb-idl.c index 42c53b831..46cc51ee7 100644 --- a/lib/ovsdb-idl.c +++ b/lib/ovsdb-idl.c @@ -25,6 +25,7 @@ #include "bitmap.h" #include "dynamic-string.h" +#include "fatal-signal.h" #include "json.h" #include "jsonrpc.h" #include "ovsdb-data.h" @@ -33,10 +34,10 @@ #include "poll-loop.h" #include "shash.h" #include "util.h" - -#define THIS_MODULE VLM_ovsdb_idl #include "vlog.h" +VLOG_DEFINE_THIS_MODULE(ovsdb_idl); + /* An arc from one idl_row to another. When row A contains a UUID that * references row B, this is represented by an arc from A (the source) to B * (the destination). @@ -111,13 +112,13 @@ static void ovsdb_idl_send_monitor_request(struct ovsdb_idl *); static void ovsdb_idl_parse_update(struct ovsdb_idl *, const struct json *); static struct ovsdb_error *ovsdb_idl_parse_update__(struct ovsdb_idl *, const struct json *); -static void ovsdb_idl_process_update(struct ovsdb_idl_table *, +static bool ovsdb_idl_process_update(struct ovsdb_idl_table *, const struct uuid *, const struct json *old, const struct json *new); static void ovsdb_idl_insert_row(struct ovsdb_idl_row *, const struct json *); static void ovsdb_idl_delete_row(struct ovsdb_idl_row *); -static void ovsdb_idl_modify_row(struct ovsdb_idl_row *, const struct json *); +static bool ovsdb_idl_modify_row(struct ovsdb_idl_row *, const struct json *); static bool ovsdb_idl_row_is_orphan(const struct ovsdb_idl_row *); static struct ovsdb_idl_row *ovsdb_idl_row_create__( @@ -135,6 +136,11 @@ static void ovsdb_idl_txn_abort_all(struct ovsdb_idl *); static bool ovsdb_idl_txn_process_reply(struct ovsdb_idl *, const struct jsonrpc_msg *msg); +/* Creates and returns a connection to database 'remote', which should be in a + * form acceptable to jsonrpc_session_open(). The connection will maintain an + * in-memory replica of the remote database whose schema is described by + * 'class'. (Ordinarily 'class' is compiled from an OVSDB schema automatically + * by ovsdb-idlc.) */ struct ovsdb_idl * ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class) { @@ -151,15 +157,15 @@ ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class) struct ovsdb_idl_table *table = &idl->tables[i]; size_t j; - assert(!shash_find(&idl->table_by_name, tc->name)); - shash_add(&idl->table_by_name, tc->name, table); + shash_add_assert(&idl->table_by_name, tc->name, table); table->class = tc; + table->modes = xmalloc(tc->n_columns); + memset(table->modes, OVSDB_IDL_MODE_RW, tc->n_columns); shash_init(&table->columns); for (j = 0; j < tc->n_columns; j++) { const struct ovsdb_idl_column *column = &tc->columns[j]; - assert(!shash_find(&table->columns, column->name)); - shash_add(&table->columns, column->name, column); + shash_add_assert(&table->columns, column->name, column); } hmap_init(&table->rows); table->idl = idl; @@ -170,6 +176,7 @@ ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class) return idl; } +/* Destroys 'idl' and all of the data structures that it manages. */ void ovsdb_idl_destroy(struct ovsdb_idl *idl) { @@ -184,6 +191,7 @@ ovsdb_idl_destroy(struct ovsdb_idl *idl) struct ovsdb_idl_table *table = &idl->tables[i]; shash_destroy(&table->columns); hmap_destroy(&table->rows); + free(table->modes); } shash_destroy(&idl->table_by_name); free(idl->tables); @@ -207,15 +215,13 @@ ovsdb_idl_clear(struct ovsdb_idl *idl) } changed = true; - HMAP_FOR_EACH_SAFE (row, next_row, struct ovsdb_idl_row, hmap_node, - &table->rows) { + HMAP_FOR_EACH_SAFE (row, next_row, hmap_node, &table->rows) { struct ovsdb_idl_arc *arc, *next_arc; if (!ovsdb_idl_row_is_orphan(row)) { ovsdb_idl_row_unparse(row); } - LIST_FOR_EACH_SAFE (arc, next_arc, struct ovsdb_idl_arc, src_node, - &row->src_arcs) { + LIST_FOR_EACH_SAFE (arc, next_arc, src_node, &row->src_arcs) { free(arc); } /* No need to do anything with dst_arcs: some node has those arcs @@ -230,9 +236,30 @@ ovsdb_idl_clear(struct ovsdb_idl *idl) } } -void +/* Processes a batch of messages from the database server on 'idl'. Returns + * true if the database as seen through 'idl' changed, false if it did not + * change. The initial fetch of the entire contents of the remote database is + * considered to be one kind of change. + * + * When this function returns false, the client may continue to use any data + * structures it obtained from 'idl' in the past. But when it returns true, + * the client must not access any of these data structures again, because they + * could have freed or reused for other purposes. + * + * This function can return occasional false positives, that is, report that + * the database changed even though it didn't. This happens if the connection + * to the database drops and reconnects, which causes the database contents to + * be reloaded even if they didn't change. (It could also happen if the + * database server sends out a "change" that reflects what we already thought + * was in the database, but the database server is not supposed to do that.) + * + * As an alternative to checking the return value, the client may check for + * changes in the value returned by ovsdb_idl_get_seqno(). + */ +bool ovsdb_idl_run(struct ovsdb_idl *idl) { + unsigned int initial_change_seqno = idl->change_seqno; int i; assert(!idl->txn); @@ -264,6 +291,7 @@ ovsdb_idl_run(struct ovsdb_idl *idl) } else if (msg->type == JSONRPC_REPLY && idl->monitor_request_id && json_equal(idl->monitor_request_id, msg->id)) { + idl->change_seqno++; json_destroy(idl->monitor_request_id); idl->monitor_request_id = NULL; ovsdb_idl_clear(idl); @@ -289,8 +317,12 @@ ovsdb_idl_run(struct ovsdb_idl *idl) } jsonrpc_msg_destroy(msg); } + + return initial_change_seqno != idl->change_seqno; } +/* Arranges for poll_block() to wake up when ovsdb_idl_run() has something to + * do or when activity occurs on a transaction on 'idl'. */ void ovsdb_idl_wait(struct ovsdb_idl *idl) { @@ -298,23 +330,94 @@ ovsdb_idl_wait(struct ovsdb_idl *idl) jsonrpc_session_recv_wait(idl->session); } +/* Returns a number that represents the state of 'idl'. When 'idl' is updated + * (by ovsdb_idl_run()), the return value changes. */ unsigned int ovsdb_idl_get_seqno(const struct ovsdb_idl *idl) { return idl->change_seqno; } +/* Returns true if 'idl' successfully connected to the remote database and + * retrieved its contents (even if the connection subsequently dropped and is + * in the process of reconnecting). If so, then 'idl' contains an atomic + * snapshot of the database's contents (but it might be arbitrarily old if the + * connection dropped). + * + * Returns false if 'idl' has never connected or retrieved the database's + * contents. If so, 'idl' is empty. */ bool ovsdb_idl_has_ever_connected(const struct ovsdb_idl *idl) { return ovsdb_idl_get_seqno(idl) != 0; } +/* Forces 'idl' to drop its connection to the database and reconnect. In the + * meantime, the contents of 'idl' will not change. */ void ovsdb_idl_force_reconnect(struct ovsdb_idl *idl) { jsonrpc_session_force_reconnect(idl->session); } + +static void +ovsdb_idl_set_mode(struct ovsdb_idl *idl, + const struct ovsdb_idl_column *column, + enum ovsdb_idl_mode mode) +{ + size_t i; + + for (i = 0; i < idl->class->n_tables; i++) { + const struct ovsdb_idl_table *table = &idl->tables[i]; + const struct ovsdb_idl_table_class *tc = table->class; + + if (column >= tc->columns && column < &tc->columns[tc->n_columns]) { + unsigned char *modep = &table->modes[column - tc->columns]; + assert(*modep == OVSDB_IDL_MODE_RW || *modep == mode); + *modep = mode; + return; + } + } + + NOT_REACHED(); +} + +/* By default, 'idl' replicates all of the columns in the remote database, and + * ovsdb_idl_run() returns true upon a change to any column in the database. + * Call this function to avoid alerting ovsdb_idl_run()'s caller upon changes + * to 'column'. + * + * This is useful for columns that a client treats as "write-only", that is, it + * updates them but doesn't want to get alerted about its own updates. It also + * won't be alerted about other clients' updates, so this is suitable only for + * use by a client that "owns" a particular column. + * + * The client must be careful not to retain pointers to data in 'column' across + * calls to ovsdb_idl_run(), even when that function returns false, because + * the client is not alerted to changes. + * + * This function should be called after ovsdb_idl_create(), but before the + * first call to ovsdb_idl_run(). For any given column, this function may be + * called or ovsdb_idl_omit() may be called, but not both. */ +void +ovsdb_idl_set_write_only(struct ovsdb_idl *idl, + const struct ovsdb_idl_column *column) +{ + ovsdb_idl_set_mode(idl, column, OVSDB_IDL_MODE_WO); +} + +/* By default, 'idl' replicates all of the columns in the remote database. + * Call this function to omit replicating 'column'. This saves CPU time and + * bandwidth to the database. + * + * This function should be called after ovsdb_idl_create(), but before the + * first call to ovsdb_idl_run(). For any given column, this function may be + * called or ovsdb_idl_set_write_only() may be called, but not both. */ +void +ovsdb_idl_omit(struct ovsdb_idl *idl, const struct ovsdb_idl_column *column) +{ + ovsdb_idl_set_mode(idl, column, OVSDB_IDL_MODE_NONE); +} static void ovsdb_idl_send_monitor_request(struct ovsdb_idl *idl) @@ -328,13 +431,15 @@ ovsdb_idl_send_monitor_request(struct ovsdb_idl *idl) const struct ovsdb_idl_table *table = &idl->tables[i]; const struct ovsdb_idl_table_class *tc = table->class; struct json *monitor_request, *columns; - size_t i; + size_t j; monitor_request = json_object_create(); columns = json_array_create_empty(); - for (i = 0; i < tc->n_columns; i++) { - const struct ovsdb_idl_column *column = &tc->columns[i]; - json_array_add(columns, json_string_create(column->name)); + for (j = 0; j < tc->n_columns; j++) { + const struct ovsdb_idl_column *column = &tc->columns[j]; + if (table->modes[j] != OVSDB_IDL_MODE_NONE) { + json_array_add(columns, json_string_create(column->name)); + } } json_object_put(monitor_request, "columns", columns); json_object_put(monitor_requests, tc->name, monitor_request); @@ -352,11 +457,7 @@ ovsdb_idl_send_monitor_request(struct ovsdb_idl *idl) static void ovsdb_idl_parse_update(struct ovsdb_idl *idl, const struct json *table_updates) { - struct ovsdb_error *error; - - idl->change_seqno++; - - error = ovsdb_idl_parse_update__(idl, table_updates); + struct ovsdb_error *error = ovsdb_idl_parse_update__(idl, table_updates); if (error) { if (!VLOG_DROP_WARN(&syntax_rl)) { char *s = ovsdb_error_to_string(error); @@ -436,7 +537,9 @@ ovsdb_idl_parse_update__(struct ovsdb_idl *idl, "and \"new\" members"); } - ovsdb_idl_process_update(table, &uuid, old_json, new_json); + if (ovsdb_idl_process_update(table, &uuid, old_json, new_json)) { + idl->change_seqno++; + } } } @@ -448,8 +551,7 @@ ovsdb_idl_get_row(struct ovsdb_idl_table *table, const struct uuid *uuid) { struct ovsdb_idl_row *row; - HMAP_FOR_EACH_WITH_HASH (row, struct ovsdb_idl_row, hmap_node, - uuid_hash(uuid), &table->rows) { + HMAP_FOR_EACH_WITH_HASH (row, hmap_node, uuid_hash(uuid), &table->rows) { if (uuid_equals(&row->uuid, uuid)) { return row; } @@ -457,7 +559,9 @@ ovsdb_idl_get_row(struct ovsdb_idl_table *table, const struct uuid *uuid) return NULL; } -static void +/* Returns true if a column with mode OVSDB_IDL_MODE_RW changed, false + * otherwise. */ +static bool ovsdb_idl_process_update(struct ovsdb_idl_table *table, const struct uuid *uuid, const struct json *old, const struct json *new) @@ -474,6 +578,7 @@ ovsdb_idl_process_update(struct ovsdb_idl_table *table, VLOG_WARN_RL(&semantic_rl, "cannot delete missing row "UUID_FMT" " "from table %s", UUID_ARGS(uuid), table->class->name); + return false; } } else if (!old) { /* Insert row. */ @@ -484,14 +589,14 @@ ovsdb_idl_process_update(struct ovsdb_idl_table *table, } else { VLOG_WARN_RL(&semantic_rl, "cannot add existing row "UUID_FMT" to " "table %s", UUID_ARGS(uuid), table->class->name); - ovsdb_idl_modify_row(row, new); + return ovsdb_idl_modify_row(row, new); } } else { /* Modify row. */ if (row) { /* XXX perhaps we should check the 'old' values? */ if (!ovsdb_idl_row_is_orphan(row)) { - ovsdb_idl_modify_row(row, new); + return ovsdb_idl_modify_row(row, new); } else { VLOG_WARN_RL(&semantic_rl, "cannot modify missing but " "referenced row "UUID_FMT" in table %s", @@ -504,13 +609,18 @@ ovsdb_idl_process_update(struct ovsdb_idl_table *table, ovsdb_idl_insert_row(ovsdb_idl_row_create(table, uuid), new); } } + + return true; } -static void +/* Returns true if a column with mode OVSDB_IDL_MODE_RW changed, false + * otherwise. */ +static bool ovsdb_idl_row_update(struct ovsdb_idl_row *row, const struct json *row_json) { struct ovsdb_idl_table *table = row->table; struct shash_node *node; + bool changed = false; SHASH_FOR_EACH (node, json_object(row_json)) { const char *column_name = node->name; @@ -527,8 +637,19 @@ ovsdb_idl_row_update(struct ovsdb_idl_row *row, const struct json *row_json) error = ovsdb_datum_from_json(&datum, &column->type, node->data, NULL); if (!error) { - ovsdb_datum_swap(&row->old[column - table->class->columns], - &datum); + unsigned int column_idx = column - table->class->columns; + struct ovsdb_datum *old = &row->old[column_idx]; + + if (!ovsdb_datum_equals(old, &datum, &column->type)) { + ovsdb_datum_swap(old, &datum); + if (table->modes[column_idx] == OVSDB_IDL_MODE_RW) { + changed = true; + } + } else { + /* Didn't really change but the OVSDB monitor protocol always + * includes every value in a row. */ + } + ovsdb_datum_destroy(&datum, &column->type); } else { char *s = ovsdb_error_to_string(error); @@ -539,6 +660,7 @@ ovsdb_idl_row_update(struct ovsdb_idl_row *row, const struct json *row_json) ovsdb_error_destroy(error); } } + return changed; } /* When a row A refers to row B through a column with a "refTable" constraint, @@ -626,8 +748,10 @@ ovsdb_idl_row_clear_new(struct ovsdb_idl_row *row) const struct ovsdb_idl_table_class *class = row->table->class; size_t i; - BITMAP_FOR_EACH_1 (i, class->n_columns, row->written) { - ovsdb_datum_destroy(&row->new[i], &class->columns[i].type); + if (row->written) { + BITMAP_FOR_EACH_1 (i, class->n_columns, row->written) { + ovsdb_datum_destroy(&row->new[i], &class->columns[i].type); + } } free(row->new); free(row->written); @@ -644,8 +768,7 @@ ovsdb_idl_row_clear_arcs(struct ovsdb_idl_row *row, bool destroy_dsts) /* Delete all forward arcs. If 'destroy_dsts', destroy any orphaned rows * that this causes to be unreferenced. */ - LIST_FOR_EACH_SAFE (arc, next, struct ovsdb_idl_arc, src_node, - &row->src_arcs) { + LIST_FOR_EACH_SAFE (arc, next, src_node, &row->src_arcs) { list_remove(&arc->dst_node); if (destroy_dsts && ovsdb_idl_row_is_orphan(arc->dst) @@ -673,8 +796,7 @@ ovsdb_idl_row_reparse_backrefs(struct ovsdb_idl_row *row) * (If duplicate arcs were possible then we would need to make sure that * 'next' didn't also point into 'arc''s destination, but we forbid * duplicate arcs.) */ - LIST_FOR_EACH_SAFE (arc, next, struct ovsdb_idl_arc, dst_node, - &row->dst_arcs) { + LIST_FOR_EACH_SAFE (arc, next, dst_node, &row->dst_arcs) { struct ovsdb_idl_row *ref = arc->src; ovsdb_idl_row_unparse(ref); @@ -743,13 +865,19 @@ ovsdb_idl_delete_row(struct ovsdb_idl_row *row) } } -static void +/* Returns true if a column with mode OVSDB_IDL_MODE_RW changed, false + * otherwise. */ +static bool ovsdb_idl_modify_row(struct ovsdb_idl_row *row, const struct json *row_json) { + bool changed; + ovsdb_idl_row_unparse(row); ovsdb_idl_row_clear_arcs(row, true); - ovsdb_idl_row_update(row, row_json); + changed = ovsdb_idl_row_update(row, row_json); ovsdb_idl_row_parse(row); + + return changed; } static bool @@ -864,6 +992,55 @@ ovsdb_idl_next_row(const struct ovsdb_idl_row *row) return next_real_row(table, hmap_next(&table->rows, &row->hmap_node)); } + +/* Reads and returns the value of 'column' within 'row'. If an ongoing + * transaction has changed 'column''s value, the modified value is returned. + * + * The caller must not modify or free the returned value. + * + * Various kinds of changes can invalidate the returned value: writing to the + * same 'column' in 'row' (e.g. with ovsdb_idl_txn_write()), deleting 'row' + * (e.g. with ovsdb_idl_txn_delete()), or completing an ongoing transaction + * (e.g. with ovsdb_idl_txn_commit() or ovsdb_idl_txn_abort()). If the + * returned value is needed for a long time, it is best to make a copy of it + * with ovsdb_datum_clone(). */ +const struct ovsdb_datum * +ovsdb_idl_read(const struct ovsdb_idl_row *row, + const struct ovsdb_idl_column *column) +{ + const struct ovsdb_idl_table_class *class = row->table->class; + size_t column_idx = column - class->columns; + + assert(row->new != NULL); + assert(column_idx < class->n_columns); + + if (row->written && bitmap_is_set(row->written, column_idx)) { + return &row->new[column_idx]; + } else if (row->old) { + return &row->old[column_idx]; + } else { + return ovsdb_datum_default(&column->type); + } +} + +/* Same as ovsdb_idl_read(), except that it also asserts that 'column' has key + * type 'key_type' and value type 'value_type'. (Scalar and set types will + * have a value type of OVSDB_TYPE_VOID.) + * + * This is useful in code that "knows" that a particular column has a given + * type, so that it will abort if someone changes the column's type without + * updating the code that uses it. */ +const struct ovsdb_datum * +ovsdb_idl_get(const struct ovsdb_idl_row *row, + const struct ovsdb_idl_column *column, + enum ovsdb_atomic_type key_type OVS_UNUSED, + enum ovsdb_atomic_type value_type OVS_UNUSED) +{ + assert(column->type.key.type == key_type); + assert(column->type.value.type == value_type); + + return ovsdb_idl_read(row, column); +} /* Transactions. */ @@ -963,8 +1140,7 @@ ovsdb_idl_txn_destroy(struct ovsdb_idl_txn *txn) free(txn->inc_table); free(txn->inc_column); json_destroy(txn->inc_where); - HMAP_FOR_EACH_SAFE (insert, next, struct ovsdb_idl_txn_insert, hmap_node, - &txn->inserted_rows) { + HMAP_FOR_EACH_SAFE (insert, next, hmap_node, &txn->inserted_rows) { free(insert); } hmap_destroy(&txn->inserted_rows); @@ -1014,8 +1190,7 @@ ovsdb_idl_txn_get_row(const struct ovsdb_idl_txn *txn, const struct uuid *uuid) { const struct ovsdb_idl_row *row; - HMAP_FOR_EACH_WITH_HASH (row, struct ovsdb_idl_row, txn_node, - uuid_hash(uuid), &txn->txn_rows) { + HMAP_FOR_EACH_WITH_HASH (row, txn_node, uuid_hash(uuid), &txn->txn_rows) { if (uuid_equals(&row->uuid, uuid)) { return row; } @@ -1073,8 +1248,7 @@ ovsdb_idl_txn_disassemble(struct ovsdb_idl_txn *txn) * transaction and fail to update the graph. */ txn->idl->txn = NULL; - HMAP_FOR_EACH_SAFE (row, next, struct ovsdb_idl_row, txn_node, - &txn->txn_rows) { + HMAP_FOR_EACH_SAFE (row, next, txn_node, &txn->txn_rows) { if (row->old) { if (row->written) { ovsdb_idl_row_unparse(row); @@ -1118,7 +1292,7 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn) json_string_create(txn->idl->class->database)); /* Add prerequisites and declarations of new rows. */ - HMAP_FOR_EACH (row, struct ovsdb_idl_row, txn_node, &txn->txn_rows) { + HMAP_FOR_EACH (row, txn_node, &txn->txn_rows) { /* XXX check that deleted rows exist even if no prereqs? */ if (row->prereqs) { const struct ovsdb_idl_table_class *class = row->table->class; @@ -1150,7 +1324,7 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn) /* Add updates. */ any_updates = false; - HMAP_FOR_EACH (row, struct ovsdb_idl_row, txn_node, &txn->txn_rows) { + HMAP_FOR_EACH (row, txn_node, &txn->txn_rows) { const struct ovsdb_idl_table_class *class = row->table->class; if (row->old == row->new) { @@ -1189,18 +1363,22 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn) row_json = json_object_create(); json_object_put(op, "row", row_json); - BITMAP_FOR_EACH_1 (idx, class->n_columns, row->written) { - const struct ovsdb_idl_column *column = &class->columns[idx]; - - if (row->old - ? !ovsdb_datum_equals(&row->old[idx], &row->new[idx], - &column->type) - : !ovsdb_datum_is_default(&row->new[idx], &column->type)) { - json_object_put(row_json, column->name, - substitute_uuids( - ovsdb_datum_to_json(&row->new[idx], - &column->type), - txn)); + if (row->written) { + BITMAP_FOR_EACH_1 (idx, class->n_columns, row->written) { + const struct ovsdb_idl_column *column = + &class->columns[idx]; + + if (row->old + ? !ovsdb_datum_equals(&row->old[idx], &row->new[idx], + &column->type) + : !ovsdb_datum_is_default(&row->new[idx], + &column->type)) { + json_object_put(row_json, column->name, + substitute_uuids( + ovsdb_datum_to_json(&row->new[idx], + &column->type), + txn)); + } } } @@ -1281,6 +1459,7 @@ ovsdb_idl_txn_commit_block(struct ovsdb_idl_txn *txn) { enum ovsdb_idl_txn_status status; + fatal_signal_run(); while ((status = ovsdb_idl_txn_commit(txn)) == TXN_INCOMPLETE) { ovsdb_idl_run(txn->idl); ovsdb_idl_wait(txn->idl); @@ -1343,7 +1522,7 @@ ovsdb_idl_txn_get_insert_uuid(const struct ovsdb_idl_txn *txn, const struct ovsdb_idl_txn_insert *insert; assert(txn->status == TXN_SUCCESS || txn->status == TXN_UNCHANGED); - HMAP_FOR_EACH_IN_BUCKET (insert, struct ovsdb_idl_txn_insert, hmap_node, + HMAP_FOR_EACH_IN_BUCKET (insert, hmap_node, uuid_hash(uuid), &txn->inserted_rows) { if (uuid_equals(uuid, &insert->dummy)) { return &insert->real; @@ -1360,24 +1539,19 @@ ovsdb_idl_txn_complete(struct ovsdb_idl_txn *txn, hmap_remove(&txn->idl->outstanding_txns, &txn->hmap_node); } -void -ovsdb_idl_txn_read(const struct ovsdb_idl_row *row, - const struct ovsdb_idl_column *column, - struct ovsdb_datum *datum) -{ - const struct ovsdb_idl_table_class *class = row->table->class; - size_t column_idx = column - class->columns; - - assert(row->new != NULL); - if (row->written && bitmap_is_set(row->written, column_idx)) { - ovsdb_datum_clone(datum, &row->new[column_idx], &column->type); - } else if (row->old) { - ovsdb_datum_clone(datum, &row->old[column_idx], &column->type); - } else { - ovsdb_datum_init_default(datum, &column->type); - } -} - +/* Writes 'datum' to the specified 'column' in 'row_'. Updates both 'row_' + * itself and the structs derived from it (e.g. the "struct ovsrec_*", for + * ovs-vswitchd). + * + * 'datum' must have the correct type for its column. The IDL does not check + * that it meets schema constraints, but ovsdb-server will do so at commit time + * so it had better be correct. + * + * A transaction must be in progress. Replication of 'column' must not have + * been disabled (by calling ovsdb_idl_omit()). + * + * Usually this function is used indirectly through one of the "set" functions + * generated by ovsdb-idlc. */ void ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_, const struct ovsdb_idl_column *column, @@ -1389,6 +1563,8 @@ ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_, assert(row->new != NULL); assert(column_idx < class->n_columns); + assert(row->table->modes[column_idx] != OVSDB_IDL_MODE_NONE); + if (hmap_node_is_null(&row->txn_node)) { hmap_insert(&row->table->idl->txn->txn_rows, &row->txn_node, uuid_hash(&row->uuid)); @@ -1409,6 +1585,32 @@ ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_, (column->parse)(row, &row->new[column_idx]); } +/* Causes the original contents of 'column' in 'row_' to be verified as a + * prerequisite to completing the transaction. That is, if 'column' in 'row_' + * changed (or if 'row_' was deleted) between the time that the IDL originally + * read its contents and the time that the transaction commits, then the + * transaction aborts and ovsdb_idl_txn_commit() returns TXN_TRY_AGAIN. + * + * The intention is that, to ensure that no transaction commits based on dirty + * reads, an application should call ovsdb_idl_txn_verify() on each data item + * read as part of a read-modify-write operation. + * + * In some cases ovsdb_idl_txn_verify() reduces to a no-op, because the current + * value of 'column' is already known: + * + * - If 'row_' is a row created by the current transaction (returned by + * ovsdb_idl_txn_insert()). + * + * - If 'column' has already been modified (with ovsdb_idl_txn_write()) + * within the current transaction. + * + * Because of the latter property, always call ovsdb_idl_txn_verify() *before* + * ovsdb_idl_txn_write() for a given read-modify-write. + * + * A transaction must be in progress. + * + * Usually this function is used indirectly through one of the "verify" + * functions generated by ovsdb-idlc. */ void ovsdb_idl_txn_verify(const struct ovsdb_idl_row *row_, const struct ovsdb_idl_column *column) @@ -1433,6 +1635,13 @@ ovsdb_idl_txn_verify(const struct ovsdb_idl_row *row_, bitmap_set1(row->prereqs, column_idx); } +/* Deletes 'row_' from its table. May free 'row_', so it must not be + * accessed afterward. + * + * A transaction must be in progress. + * + * Usually this function is used indirectly through one of the "delete" + * functions generated by ovsdb-idlc. */ void ovsdb_idl_txn_delete(const struct ovsdb_idl_row *row_) { @@ -1456,15 +1665,34 @@ ovsdb_idl_txn_delete(const struct ovsdb_idl_row *row_) row->new = NULL; } +/* Inserts and returns a new row in the table with the specified 'class' in the + * database with open transaction 'txn'. + * + * The new row is assigned a provisional UUID. If 'uuid' is null then one is + * randomly generated; otherwise 'uuid' should specify a randomly generated + * UUID not otherwise in use. ovsdb-server will assign a different UUID when + * 'txn' is committed, but the IDL will replace any uses of the provisional + * UUID in the data to be to be committed by the UUID assigned by + * ovsdb-server. + * + * Usually this function is used indirectly through one of the "insert" + * functions generated by ovsdb-idlc. */ const struct ovsdb_idl_row * ovsdb_idl_txn_insert(struct ovsdb_idl_txn *txn, - const struct ovsdb_idl_table_class *class) + const struct ovsdb_idl_table_class *class, + const struct uuid *uuid) { struct ovsdb_idl_row *row = ovsdb_idl_row_create__(class); - uuid_generate(&row->uuid); + + if (uuid) { + assert(!ovsdb_idl_txn_get_row(txn, uuid)); + row->uuid = *uuid; + } else { + uuid_generate(&row->uuid); + } + row->table = ovsdb_idl_table_from_class(txn->idl, class); row->new = xmalloc(class->n_columns * sizeof *row->new); - row->written = bitmap_allocate(class->n_columns); hmap_insert(&row->table->rows, &row->hmap_node, uuid_hash(&row->uuid)); hmap_insert(&txn->txn_rows, &row->txn_node, uuid_hash(&row->uuid)); return row; @@ -1475,8 +1703,7 @@ ovsdb_idl_txn_abort_all(struct ovsdb_idl *idl) { struct ovsdb_idl_txn *txn; - HMAP_FOR_EACH (txn, struct ovsdb_idl_txn, hmap_node, - &idl->outstanding_txns) { + HMAP_FOR_EACH (txn, hmap_node, &idl->outstanding_txns) { ovsdb_idl_txn_complete(txn, TXN_TRY_AGAIN); } } @@ -1486,7 +1713,7 @@ ovsdb_idl_txn_find(struct ovsdb_idl *idl, const struct json *id) { struct ovsdb_idl_txn *txn; - HMAP_FOR_EACH_WITH_HASH (txn, struct ovsdb_idl_txn, hmap_node, + HMAP_FOR_EACH_WITH_HASH (txn, hmap_node, json_hash(id, 0), &idl->outstanding_txns) { if (json_equal(id, txn->request_id)) { return txn; @@ -1520,7 +1747,7 @@ ovsdb_idl_txn_process_inc_reply(struct ovsdb_idl_txn *txn, if (txn->inc_index + 2 > results->n) { VLOG_WARN_RL(&syntax_rl, "reply does not contain enough operations " - "for increment (has %u, needs %u)", + "for increment (has %zu, needs %u)", results->n, txn->inc_index + 2); return false; } @@ -1534,7 +1761,7 @@ ovsdb_idl_txn_process_inc_reply(struct ovsdb_idl_txn *txn, } if (count->u.integer != 1) { VLOG_WARN_RL(&syntax_rl, - "\"mutate\" reply \"count\" is %"PRId64" instead of 1", + "\"mutate\" reply \"count\" is %lld instead of 1", count->u.integer); return false; } @@ -1545,7 +1772,7 @@ ovsdb_idl_txn_process_inc_reply(struct ovsdb_idl_txn *txn, return false; } if (rows->u.array.n != 1) { - VLOG_WARN_RL(&syntax_rl, "\"select\" reply \"rows\" has %u elements " + VLOG_WARN_RL(&syntax_rl, "\"select\" reply \"rows\" has %zu elements " "instead of 1", rows->u.array.n); return false; @@ -1575,7 +1802,7 @@ ovsdb_idl_txn_process_insert_reply(struct ovsdb_idl_txn_insert *insert, if (insert->op_index >= results->n) { VLOG_WARN_RL(&syntax_rl, "reply does not contain enough operations " - "for insert (has %u, needs %u)", + "for insert (has %zu, needs %u)", results->n, insert->op_index); return false; } @@ -1666,8 +1893,7 @@ ovsdb_idl_txn_process_reply(struct ovsdb_idl *idl, hard_errors++; } - HMAP_FOR_EACH (insert, struct ovsdb_idl_txn_insert, hmap_node, - &txn->inserted_rows) { + HMAP_FOR_EACH (insert, hmap_node, &txn->inserted_rows) { if (!ovsdb_idl_txn_process_insert_reply(insert, ops)) { hard_errors++; }