X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fovsdb-idl.c;h=fd15ea96f3f13103431ecdfeeda55720ca26e1d9;hb=7174e5aed2a6d2877c1760d2ae921ae24d7accb5;hp=bca822464240307cdfe1250cce7c05417396e08f;hpb=02dd3123a0e312f1d33403e744af52dd6096f12d;p=sliver-openvswitch.git diff --git a/lib/ovsdb-idl.c b/lib/ovsdb-idl.c index bca822464..fd15ea96f 100644 --- a/lib/ovsdb-idl.c +++ b/lib/ovsdb-idl.c @@ -1,4 +1,4 @@ -/* 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. @@ -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). @@ -65,7 +66,7 @@ struct ovsdb_idl { const struct ovsdb_idl_class *class; struct jsonrpc_session *session; struct shash table_by_name; - struct ovsdb_idl_table *tables; + struct ovsdb_idl_table *tables; /* Contains "struct ovsdb_idl_table *"s.*/ struct json *monitor_request_id; unsigned int last_monitor_request_seqno; unsigned int change_seqno; @@ -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__( @@ -135,12 +136,33 @@ 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.) + * + * If 'monitor_everything_by_default' is true, then everything in the remote + * database will be replicated by default. ovsdb_idl_omit() and + * ovsdb_idl_omit_alert() may be used to selectively drop some columns from + * monitoring. + * + * If 'monitor_everything_by_default' is false, then no columns or tables will + * be replicated by default. ovsdb_idl_add_column() and ovsdb_idl_add_table() + * must be used to choose some columns or tables to replicate. + */ struct ovsdb_idl * -ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class) +ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class, + bool monitor_everything_by_default) { struct ovsdb_idl *idl; + uint8_t default_mode; size_t i; + default_mode = (monitor_everything_by_default + ? OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT + : 0); + idl = xzalloc(sizeof *idl); idl->class = class; idl->session = jsonrpc_session_open(remote); @@ -151,15 +173,16 @@ 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, default_mode, tc->n_columns); + table->need_table = false; 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 +193,7 @@ 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 +208,7 @@ 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 +232,13 @@ 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 @@ -230,15 +253,36 @@ 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); jsonrpc_session_run(idl->session); for (i = 0; jsonrpc_session_is_connected(idl->session) && i < 50; i++) { - struct jsonrpc_msg *msg, *reply; + struct jsonrpc_msg *msg; unsigned int seqno; seqno = jsonrpc_session_get_seqno(idl->session); @@ -254,7 +298,6 @@ ovsdb_idl_run(struct ovsdb_idl *idl) break; } - reply = NULL; if (msg->type == JSONRPC_NOTIFY && !strcmp(msg->method, "update") && msg->params->type == JSON_ARRAY @@ -264,12 +307,12 @@ 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); ovsdb_idl_parse_update(idl, msg->result); - } else if (msg->type == JSONRPC_REPLY - && msg->id && msg->id->type == JSON_STRING + } else if (msg->type == JSONRPC_REPLY && msg->id->type == JSON_STRING && !strcmp(msg->id->u.string, "echo")) { /* It's a reply to our echo request. Ignore it. */ } else if ((msg->type == JSONRPC_ERROR @@ -284,13 +327,14 @@ ovsdb_idl_run(struct ovsdb_idl *idl) jsonrpc_session_get_name(idl->session), jsonrpc_msg_type_to_string(msg->type)); } - if (reply) { - jsonrpc_session_send(idl->session, reply); - } 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) { @@ -298,24 +342,144 @@ 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 unsigned char * +ovsdb_idl_get_mode(struct ovsdb_idl *idl, + const struct ovsdb_idl_column *column) +{ + size_t i; + + assert(!idl->change_seqno); + + 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]) { + return &table->modes[column - tc->columns]; + } + } + + NOT_REACHED(); +} + +static void +add_ref_table(struct ovsdb_idl *idl, const struct ovsdb_base_type *base) +{ + if (base->type == OVSDB_TYPE_UUID && base->u.uuid.refTableName) { + struct ovsdb_idl_table *table; + + table = shash_find_data(&idl->table_by_name, + base->u.uuid.refTableName); + if (table) { + table->need_table = true; + } else { + VLOG_WARN("%s IDL class missing referenced table %s", + idl->class->database, base->u.uuid.refTableName); + } + } +} + +/* Turns on OVSDB_IDL_MONITOR and OVSDB_IDL_ALERT for 'column' in 'idl'. Also + * ensures that any tables referenced by 'column' will be replicated, even if + * no columns in that table are selected for replication (see + * ovsdb_idl_add_table() for more information). + * + * This function is only useful if 'monitor_everything_by_default' was false in + * the call to ovsdb_idl_create(). This function should be called between + * ovsdb_idl_create() and the first call to ovsdb_idl_run(). + */ +void +ovsdb_idl_add_column(struct ovsdb_idl *idl, + const struct ovsdb_idl_column *column) +{ + *ovsdb_idl_get_mode(idl, column) = OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT; + add_ref_table(idl, &column->type.key); + add_ref_table(idl, &column->type.value); +} + +/* Ensures that the table with class 'tc' will be replicated on 'idl' even if + * no columns are selected for replication. This can be useful because it + * allows 'idl' to keep track of what rows in the table actually exist, which + * in turn allows columns that reference the table to have accurate contents. + * (The IDL presents the database with references to rows that do not exist + * removed.) + * + * This function is only useful if 'monitor_everything_by_default' was false in + * the call to ovsdb_idl_create(). This function should be called between + * ovsdb_idl_create() and the first call to ovsdb_idl_run(). + */ +void +ovsdb_idl_add_table(struct ovsdb_idl *idl, + const struct ovsdb_idl_table_class *tc) +{ + size_t i; + + for (i = 0; i < idl->class->n_tables; i++) { + struct ovsdb_idl_table *table = &idl->tables[i]; + + if (table->class == tc) { + table->need_table = true; + return; + } + } + + NOT_REACHED(); +} + +/* Turns off OVSDB_IDL_ALERT for 'column' in 'idl'. + * + * This function should be called between ovsdb_idl_create() and the first call + * to ovsdb_idl_run(). + */ +void +ovsdb_idl_omit_alert(struct ovsdb_idl *idl, + const struct ovsdb_idl_column *column) +{ + *ovsdb_idl_get_mode(idl, column) &= ~OVSDB_IDL_ALERT; +} + +/* Sets the mode for 'column' in 'idl' to 0. See the big comment above + * OVSDB_IDL_MONITOR for details. + * + * This function should be called between ovsdb_idl_create() and the first call + * to ovsdb_idl_run(). + */ +void +ovsdb_idl_omit(struct ovsdb_idl *idl, const struct ovsdb_idl_column *column) +{ + *ovsdb_idl_get_mode(idl, column) = 0; +} + static void ovsdb_idl_send_monitor_request(struct ovsdb_idl *idl) { @@ -328,16 +492,24 @@ 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; + + columns = table->need_table ? json_array_create_empty() : NULL; + for (j = 0; j < tc->n_columns; j++) { + const struct ovsdb_idl_column *column = &tc->columns[j]; + if (table->modes[j] & OVSDB_IDL_MONITOR) { + if (!columns) { + columns = json_array_create_empty(); + } + json_array_add(columns, json_string_create(column->name)); + } + } - 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)); + if (columns) { + monitor_request = json_object_create(); + json_object_put(monitor_request, "columns", columns); + json_object_put(monitor_requests, tc->name, monitor_request); } - json_object_put(monitor_request, "columns", columns); - json_object_put(monitor_requests, tc->name, monitor_request); } json_destroy(idl->monitor_request_id); @@ -352,11 +524,7 @@ 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 +604,9 @@ 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 +618,7 @@ 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 +626,9 @@ 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 +645,7 @@ 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 +656,14 @@ 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 +676,18 @@ 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 +704,19 @@ 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_ALERT) { + 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); @@ -539,12 +727,44 @@ 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, + * but row B does not exist, row B is called an "orphan row". Orphan rows + * should not persist, because the database enforces referential integrity, but + * they can appear transiently as changes from the database are received (the + * database doesn't try to topologically sort them and circular references mean + * it isn't always possible anyhow). + * + * This function returns true if 'row' is an orphan row, otherwise false. + */ static bool ovsdb_idl_row_is_orphan(const struct ovsdb_idl_row *row) { - return !row->old; + return !row->old && !row->new; +} + +/* Returns true if 'row' is conceptually part of the database as modified by + * the current transaction (if any), false otherwise. + * + * This function will return true if 'row' is not an orphan (see the comment on + * ovsdb_idl_row_is_orphan()) and: + * + * - 'row' exists in the database and has not been deleted within the + * current transaction (if any). + * + * - 'row' was inserted within the current transaction and has not been + * deleted. (In the latter case you should not have passed 'row' in at + * all, because ovsdb_idl_txn_delete() freed it.) + * + * This function will return false if 'row' is an orphan or if 'row' was + * deleted within the current transaction. + */ +static bool +ovsdb_idl_row_exists(const struct ovsdb_idl_row *row) +{ + return row->new != NULL; } static void @@ -595,8 +815,10 @@ 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); @@ -613,8 +835,7 @@ 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) @@ -642,8 +863,7 @@ 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); @@ -712,13 +932,19 @@ 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 @@ -810,7 +1036,7 @@ next_real_row(struct ovsdb_idl_table *table, struct hmap_node *node) struct ovsdb_idl_row *row; row = CONTAINER_OF(node, struct ovsdb_idl_row, hmap_node); - if (row->new || !ovsdb_idl_row_is_orphan(row)) { + if (ovsdb_idl_row_exists(row)) { return row; } } @@ -833,6 +1059,64 @@ 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); +} + +/* Returns false if 'row' was obtained from the IDL, true if it was initialized + * to all-zero-bits by some other entity. If 'row' was set up some other way + * then the return value is indeterminate. */ +bool +ovsdb_idl_row_is_synthetic(const struct ovsdb_idl_row *row) +{ + return row->table == NULL; +} /* Transactions. */ @@ -883,13 +1167,22 @@ ovsdb_idl_txn_create(struct ovsdb_idl *idl) return txn; } +/* Appends 's', which is treated as a printf()-type format string, to the + * comments that will be passed to the OVSDB server when 'txn' is committed. + * (The comment will be committed to the OVSDB log, which "ovsdb-tool + * show-log" can print in a relatively human-readable form.) */ void -ovsdb_idl_txn_add_comment(struct ovsdb_idl_txn *txn, const char *s) +ovsdb_idl_txn_add_comment(struct ovsdb_idl_txn *txn, const char *s, ...) { + va_list args; + if (txn->comment.length) { ds_put_char(&txn->comment, '\n'); } - ds_put_cstr(&txn->comment, s); + + va_start(args, s); + ds_put_format_valist(&txn->comment, s, args); + va_end(args); } void @@ -923,8 +1216,7 @@ 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); @@ -974,8 +1266,7 @@ 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; } @@ -1033,8 +1324,7 @@ 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); @@ -1078,7 +1368,7 @@ 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; @@ -1110,18 +1400,22 @@ 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) { continue; } else if (!row->new) { - struct json *op = json_object_create(); - json_object_put_string(op, "op", "delete"); - json_object_put_string(op, "table", class->name); - json_object_put(op, "where", where_uuid_equals(&row->uuid)); - json_array_add(operations, op); - any_updates = true; + if (class->is_root) { + struct json *op = json_object_create(); + json_object_put_string(op, "op", "delete"); + json_object_put_string(op, "table", class->name); + json_object_put(op, "where", where_uuid_equals(&row->uuid)); + json_array_add(operations, op); + any_updates = true; + } else { + /* Let ovsdb-server decide whether to really delete it. */ + } } else { struct json *row_json; struct json *op; @@ -1149,18 +1443,20 @@ 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_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)); + } } } @@ -1226,13 +1522,31 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn) hmap_insert(&txn->idl->outstanding_txns, &txn->hmap_node, json_hash(txn->request_id, 0)); } else { - txn->status = TXN_INCOMPLETE; + txn->status = TXN_TRY_AGAIN; } ovsdb_idl_txn_disassemble(txn); return txn->status; } +/* Attempts to commit 'txn', blocking until the commit either succeeds or + * fails. Returns the final commit status, which may be any TXN_* value other + * than TXN_INCOMPLETE. */ +enum ovsdb_idl_txn_status +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); + ovsdb_idl_txn_wait(txn); + poll_block(); + } + return status; +} + int64_t ovsdb_idl_txn_get_increment_new_value(const struct ovsdb_idl_txn *txn) { @@ -1286,7 +1600,7 @@ 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; @@ -1303,24 +1617,19 @@ 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, @@ -1332,6 +1641,24 @@ ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_, assert(row->new != NULL); assert(column_idx < class->n_columns); + assert(row->old == NULL || + row->table->modes[column_idx] & OVSDB_IDL_MONITOR); + + /* If this is a write-only column and the datum being written is the same + * as the one already there, just skip the update entirely. This is worth + * optimizing because we have a lot of columns that get periodically + * refreshed into the database but don't actually change that often. + * + * We don't do this for read/write columns because that would break + * atomicity of transactions--some other client might have written a + * different value in that column since we read it. */ + if (row->table->modes[column_idx] == OVSDB_IDL_MONITOR + && ovsdb_datum_equals(ovsdb_idl_read(row, column), + datum, &column->type)) { + ovsdb_datum_destroy(datum, &column->type); + return; + } + if (hmap_node_is_null(&row->txn_node)) { hmap_insert(&row->table->idl->txn->txn_rows, &row->txn_node, uuid_hash(&row->uuid)); @@ -1352,6 +1679,32 @@ 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) @@ -1361,6 +1714,8 @@ ovsdb_idl_txn_verify(const struct ovsdb_idl_row *row_, size_t column_idx = column - class->columns; assert(row->new != NULL); + assert(row->old == NULL || + row->table->modes[column_idx] & OVSDB_IDL_MONITOR); if (!row->old || (row->written && bitmap_is_set(row->written, column_idx))) { return; @@ -1376,6 +1731,13 @@ 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_) { @@ -1399,15 +1761,34 @@ 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; @@ -1418,8 +1799,7 @@ 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); } } @@ -1429,7 +1809,7 @@ 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; @@ -1463,7 +1843,7 @@ 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; } @@ -1477,7 +1857,7 @@ 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; } @@ -1488,7 +1868,7 @@ 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; @@ -1518,7 +1898,7 @@ 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; } @@ -1609,8 +1989,7 @@ 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++; } @@ -1633,3 +2012,10 @@ ovsdb_idl_txn_get(const struct ovsdb_idl_row *row) assert(txn != NULL); return txn; } + +struct ovsdb_idl * +ovsdb_idl_txn_get_idl (struct ovsdb_idl_txn *txn) +{ + return txn->idl; +} +