Copyright (C) Andrew Tridgell 2006
- This library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2 of the License, or (at your option) any later version.
-
- This library is distributed in the hope that it will be useful,
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with this library; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
-#include "lib/events/events.h"
+#include "lib/tevent/tevent.h"
#include "lib/tdb/include/tdb.h"
#include "system/network.h"
#include "system/filesys.h"
}
-/*
- this is the dummy null procedure that all databases support
-*/
-static int ctdb_null_func(struct ctdb_call_info *call)
-{
- return 0;
-}
-
-/*
- this is a plain fetch procedure that all databases support
-*/
-static int ctdb_fetch_func(struct ctdb_call_info *call)
-{
- call->reply_data = &call->record_data;
- return 0;
-}
-
-
/*
return the lmaster given a key
*/
TDB_DATA key,
struct ctdb_ltdb_header *header)
{
- header->rsn = 0;
+ ZERO_STRUCTP(header);
/* initial dmaster is the lmaster */
header->dmaster = ctdb_lmaster(ctdb_db->ctdb, &key);
- header->laccessor = header->dmaster;
- header->lacount = 0;
}
TDB_DATA d2;
/* return an initial header */
if (rec.dptr) free(rec.dptr);
+ if (ctdb->vnn_map == NULL) {
+ /* called from the client */
+ ZERO_STRUCTP(data);
+ header->dmaster = (uint32_t)-1;
+ return -1;
+ }
ltdb_initial_header(ctdb_db, key, header);
ZERO_STRUCT(d2);
if (data) {
/*
- fetch a record from the ltdb, separating out the header information
- and returning the body of the record. A valid (initial) header is
- returned if the record is not present
+ write a record to a normal database
*/
int ctdb_ltdb_store(struct ctdb_db_context *ctdb_db, TDB_DATA key,
struct ctdb_ltdb_header *header, TDB_DATA data)
struct ctdb_context *ctdb = ctdb_db->ctdb;
TDB_DATA rec;
int ret;
+ bool seqnum_suppressed = false;
+
+ if (ctdb->flags & CTDB_FLAG_TORTURE) {
+ struct ctdb_ltdb_header *h2;
+ rec = tdb_fetch(ctdb_db->ltdb->tdb, key);
+ h2 = (struct ctdb_ltdb_header *)rec.dptr;
+ if (rec.dptr && rec.dsize >= sizeof(h2) && h2->rsn > header->rsn) {
+ DEBUG(DEBUG_CRIT,("RSN regression! %llu %llu\n",
+ (unsigned long long)h2->rsn, (unsigned long long)header->rsn));
+ }
+ if (rec.dptr) free(rec.dptr);
+ }
rec.dsize = sizeof(*header) + data.dsize;
rec.dptr = talloc_size(ctdb, rec.dsize);
memcpy(rec.dptr, header, sizeof(*header));
memcpy(rec.dptr + sizeof(*header), data.dptr, data.dsize);
+ /* Databases with seqnum updates enabled only get their seqnum
+ changes when/if we modify the data */
+ if (ctdb_db->seqnum_update != NULL) {
+ TDB_DATA old;
+ old = tdb_fetch(ctdb_db->ltdb->tdb, key);
+
+ if ( (old.dsize == rec.dsize)
+ && !memcmp(old.dptr+sizeof(struct ctdb_ltdb_header),
+ rec.dptr+sizeof(struct ctdb_ltdb_header),
+ rec.dsize-sizeof(struct ctdb_ltdb_header)) ) {
+ tdb_remove_flags(ctdb_db->ltdb->tdb, TDB_SEQNUM);
+ seqnum_suppressed = true;
+ }
+ if (old.dptr) free(old.dptr);
+ }
ret = tdb_store(ctdb_db->ltdb->tdb, key, rec, TDB_REPLACE);
+ if (ret != 0) {
+ DEBUG(DEBUG_ERR, (__location__ " Failed to store dynamic data\n"));
+ }
+ if (seqnum_suppressed) {
+ tdb_add_flags(ctdb_db->ltdb->tdb, TDB_SEQNUM);
+ }
+
talloc_free(rec.dptr);
return ret;
}
-
/*
lock a record in the ltdb, given a key
*/
{
int ret = tdb_chainunlock(ctdb_db->ltdb->tdb, key);
if (ret != 0) {
- DEBUG(0,("tdb_chainunlock failed\n"));
- }
- return ret;
-}
-
-struct lock_fetch_state {
- struct ctdb_context *ctdb;
- void (*recv_pkt)(void *, uint8_t *, uint32_t);
- void *recv_context;
- struct ctdb_req_header *hdr;
-};
-
-/*
- called when we should retry the operation
- */
-static void lock_fetch_callback(void *p)
-{
- struct lock_fetch_state *state = talloc_get_type(p, struct lock_fetch_state);
- state->recv_pkt(state->recv_context, (uint8_t *)state->hdr, state->hdr->length);
- DEBUG(2,(__location__ " PACKET REQUEUED\n"));
-}
-
-
-/*
- do a non-blocking ltdb_lock, deferring this ctdb request until we
- have the chainlock
-
- It does the following:
-
- 1) tries to get the chainlock. If it succeeds, then it returns 0
-
- 2) if it fails to get a chainlock immediately then it sets up a
- non-blocking chainlock via ctdb_lockwait, and when it gets the
- chainlock it re-submits this ctdb request to the main packet
- receive function
-
- This effectively queues all ctdb requests that cannot be
- immediately satisfied until it can get the lock. This means that
- the main ctdb daemon will not block waiting for a chainlock held by
- a client
-
- There are 3 possible return values:
-
- 0: means that it got the lock immediately.
- -1: means that it failed to get the lock, and won't retry
- -2: means that it failed to get the lock immediately, but will retry
- */
-int ctdb_ltdb_lock_requeue(struct ctdb_db_context *ctdb_db,
- TDB_DATA key, struct ctdb_req_header *hdr,
- void (*recv_pkt)(void *, uint8_t *, uint32_t ),
- void *recv_context)
-{
- int ret;
- struct tdb_context *tdb = ctdb_db->ltdb->tdb;
- struct lockwait_handle *h;
- struct lock_fetch_state *state;
-
- ret = tdb_chainlock_nonblock(tdb, key);
-
- if (ret != 0 &&
- !(errno == EACCES || errno == EAGAIN || errno == EDEADLK)) {
- /* a hard failure - don't try again */
- return -1;
- }
-
- /* when torturing, ensure we test the contended path */
- if ((ctdb_db->ctdb->flags & CTDB_FLAG_TORTURE) &&
- random() % 5 == 0) {
- ret = -1;
- tdb_chainunlock(tdb, key);
- }
-
- /* first the non-contended path */
- if (ret == 0) {
- return 0;
- }
-
- state = talloc(hdr, struct lock_fetch_state);
- state->ctdb = ctdb_db->ctdb;
- state->hdr = hdr;
- state->recv_pkt = recv_pkt;
- state->recv_context = recv_context;
-
- /* now the contended path */
- h = ctdb_lockwait(ctdb_db, key, lock_fetch_callback, state);
- if (h == NULL) {
- tdb_chainunlock(tdb, key);
- return -1;
- }
-
- /* we need to move the packet off the temporary context in ctdb_recv_pkt(),
- so it won't be freed yet */
- talloc_steal(state, hdr);
- talloc_steal(state, h);
-
- /* now tell the caller than we will retry asynchronously */
- return -2;
-}
-
-/*
- a varient of ctdb_ltdb_lock_requeue that also fetches the record
- */
-int ctdb_ltdb_lock_fetch_requeue(struct ctdb_db_context *ctdb_db,
- TDB_DATA key, struct ctdb_ltdb_header *header,
- struct ctdb_req_header *hdr, TDB_DATA *data,
- void (*recv_pkt)(void *, uint8_t *, uint32_t ),
- void *recv_context)
-{
- int ret;
-
- ret = ctdb_ltdb_lock_requeue(ctdb_db, key, hdr, recv_pkt, recv_context);
- if (ret == 0) {
- ret = ctdb_ltdb_fetch(ctdb_db, key, header, hdr, data);
- if (ret != 0) {
- ctdb_ltdb_unlock(ctdb_db, key);
- }
+ DEBUG(DEBUG_ERR,("tdb_chainunlock failed on db %s [%s]\n", ctdb_db->db_name, tdb_errorstr(ctdb_db->ltdb->tdb)));
}
return ret;
}
-
-
-/*
- a client has asked to attach a new database
- */
-int32_t ctdb_control_db_attach(struct ctdb_context *ctdb, TDB_DATA indata,
- TDB_DATA *outdata)
-{
- const char *db_name = (const char *)indata.dptr;
- struct ctdb_db_context *ctdb_db, *tmp_db;
- int ret;
-
- /* see if we already have this name */
- for (tmp_db=ctdb->db_list;tmp_db;tmp_db=tmp_db->next) {
- if (strcmp(db_name, tmp_db->db_name) == 0) {
- /* this is not an error */
- outdata->dptr = (uint8_t *)&tmp_db->db_id;
- outdata->dsize = sizeof(tmp_db->db_id);
- return 0;
- }
- }
-
- ctdb_db = talloc_zero(ctdb, struct ctdb_db_context);
- CTDB_NO_MEMORY(ctdb, ctdb_db);
-
- ctdb_db->ctdb = ctdb;
- ctdb_db->db_name = talloc_strdup(ctdb_db, db_name);
- CTDB_NO_MEMORY(ctdb, ctdb_db->db_name);
-
- ctdb_db->db_id = ctdb_hash(&indata);
-
- outdata->dptr = (uint8_t *)&ctdb_db->db_id;
- outdata->dsize = sizeof(ctdb_db->db_id);
-
- /* check for hash collisions */
- for (tmp_db=ctdb->db_list;tmp_db;tmp_db=tmp_db->next) {
- if (tmp_db->db_id == ctdb_db->db_id) {
- DEBUG(0,("db_id 0x%x hash collision. name1='%s' name2='%s'\n",
- db_name, tmp_db->db_name));
- talloc_free(ctdb_db);
- return -1;
- }
- }
-
- if (ctdb->db_directory == NULL) {
- ctdb->db_directory = VARDIR "/ctdb";
- }
-
- /* make sure the db directory exists */
- if (mkdir(ctdb->db_directory, 0700) == -1 && errno != EEXIST) {
- DEBUG(0,(__location__ " Unable to create ctdb directory '%s'\n",
- ctdb->db_directory));
- talloc_free(ctdb_db);
- return -1;
- }
-
- /* open the database */
- ctdb_db->db_path = talloc_asprintf(ctdb_db, "%s/%s.%u",
- ctdb->db_directory,
- db_name, ctdb->vnn);
-
- ctdb_db->ltdb = tdb_wrap_open(ctdb, ctdb_db->db_path, 0,
- TDB_CLEAR_IF_FIRST, O_CREAT|O_RDWR, 0666);
- if (ctdb_db->ltdb == NULL) {
- DEBUG(0,("Failed to open tdb '%s'\n", ctdb_db->db_path));
- talloc_free(ctdb_db);
- return -1;
- }
-
- DLIST_ADD(ctdb->db_list, ctdb_db);
-
- /*
- all databases support the "null" function. we need this in
- order to do forced migration of records
- */
- ret = ctdb_daemon_set_call(ctdb, ctdb_db->db_id, ctdb_null_func, CTDB_NULL_FUNC);
- if (ret != 0) {
- DEBUG(0,("Failed to setup null function for '%s'\n", ctdb_db->db_name));
- talloc_free(ctdb_db);
- return -1;
- }
-
- /*
- all databases support the "fetch" function. we need this
- for efficient Samba3 ctdb fetch
- */
- ret = ctdb_daemon_set_call(ctdb, ctdb_db->db_id, ctdb_fetch_func, CTDB_FETCH_FUNC);
- if (ret != 0) {
- DEBUG(0,("Failed to setup fetch function for '%s'\n", ctdb_db->db_name));
- talloc_free(ctdb_db);
- return -1;
- }
-
- /* tell all the other nodes about this database */
- ctdb_daemon_send_control(ctdb, CTDB_BROADCAST_VNNMAP, 0,
- CTDB_CONTROL_DB_ATTACH, 0, CTDB_CTRL_FLAG_NOREPLY,
- indata, NULL, NULL);
-
- DEBUG(1,("Attached to database '%s'\n", ctdb_db->db_path));
-
- /* success */
- return 0;
-}
-
-/*
- called when a broadcast seqnum update comes in
- */
-int32_t ctdb_ltdb_update_seqnum(struct ctdb_context *ctdb, uint32_t db_id, uint32_t srcnode)
-{
- struct ctdb_db_context *ctdb_db;
- if (srcnode == ctdb->vnn) {
- /* don't update ourselves! */
- return 0;
- }
-
- ctdb_db = find_ctdb_db(ctdb, db_id);
- if (!ctdb_db) {
- DEBUG(0,("Unknown db_id 0x%x in ctdb_ltdb_update_seqnum\n"));
- return -1;
- }
-
- tdb_increment_seqnum_nonblock(ctdb_db->ltdb->tdb);
- ctdb_db->seqnum = tdb_get_seqnum(ctdb_db->ltdb->tdb);
- return 0;
-}
-
-/*
- timer to check for seqnum changes in a ltdb and propogate them
- */
-static void ctdb_ltdb_seqnum_check(struct event_context *ev, struct timed_event *te,
- struct timeval t, void *p)
-{
- struct ctdb_db_context *ctdb_db = talloc_get_type(p, struct ctdb_db_context);
- struct ctdb_context *ctdb = ctdb_db->ctdb;
- uint32_t new_seqnum = tdb_get_seqnum(ctdb_db->ltdb->tdb);
- if (new_seqnum != ctdb_db->seqnum) {
- /* something has changed - propogate it */
- TDB_DATA data;
- data.dptr = (uint8_t *)&ctdb_db->db_id;
- data.dsize = sizeof(uint32_t);
- ctdb_daemon_send_control(ctdb, CTDB_BROADCAST_VNNMAP, 0,
- CTDB_CONTROL_UPDATE_SEQNUM, 0, CTDB_CTRL_FLAG_NOREPLY,
- data, NULL, NULL);
- }
- ctdb_db->seqnum = new_seqnum;
-
- /* setup a new timer */
- ctdb_db->te = event_add_timed(ctdb->ev, ctdb_db,
- timeval_current_ofs(ctdb->seqnum_frequency, 0),
- ctdb_ltdb_seqnum_check, ctdb_db);
-}
-
-/*
- enable seqnum handling on this db
- */
-int32_t ctdb_ltdb_enable_seqnum(struct ctdb_context *ctdb, uint32_t db_id)
-{
- struct ctdb_db_context *ctdb_db;
- ctdb_db = find_ctdb_db(ctdb, db_id);
- if (!ctdb_db) {
- DEBUG(0,("Unknown db_id 0x%x in ctdb_ltdb_enable_seqnum\n"));
- return -1;
- }
-
- if (ctdb_db->te == NULL) {
- ctdb_db->te = event_add_timed(ctdb->ev, ctdb_db,
- timeval_current_ofs(ctdb->seqnum_frequency, 0),
- ctdb_ltdb_seqnum_check, ctdb_db);
- }
-
- tdb_enable_seqnum(ctdb_db->ltdb->tdb);
- ctdb_db->seqnum = tdb_get_seqnum(ctdb_db->ltdb->tdb);
- return 0;
-}
-
-/*
- enable seqnum handling on this db
- */
-int32_t ctdb_ltdb_set_seqnum_frequency(struct ctdb_context *ctdb, uint32_t frequency)
-{
- ctdb->seqnum_frequency = frequency;
- return 0;
-}
git.samba.org / sahlberg / ctdb.git / blobdiff