[PATCH] replace tdb database by simple lockless file database

This makes the udev operation completely lockless by storing a
file for every node in /dev/.udevdb/* This solved the problem
with deadlocking concurrent udev processes waiting for each other
to release the file lock under heavy load.

1 files changed, 0 insertions, 201 deletions

diff --git a/tdb/tdbback.c b/tdb/tdbback.c
deleted file mode 100644
index 744cface55..0000000000
--- a/tdb/tdbback.c
+++ /dev/null
@@ -1,201 +0,0 @@
-/* 
-   Unix SMB/CIFS implementation.
-   low level tdb backup and restore utility
-   Copyright (C) Andrew Tridgell              2002
-
-   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 2 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 General Public License for more details.
-   
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
-#include <errno.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <string.h>
-#include <fcntl.h>
-#include <time.h>
-#include <sys/mman.h>
-#include <sys/stat.h>
-#include <sys/time.h>
-#include <ctype.h>
-#include <signal.h>
-#include "tdb.h"
-
-static int failed;
-
-char *add_suffix(const char *name, const char *suffix)
-{
-	char *ret;
-	int len = strlen(name) + strlen(suffix) + 1;
-	ret = malloc(len);
-	if (!ret) {
-		fprintf(stderr,"Out of memory!\n");
-		exit(1);
-	}
-	strncpy(ret, name, len);
-	strncat(ret, suffix, len);
-	return ret;
-}
-
-static int copy_fn(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, void *state)
-{
-	TDB_CONTEXT *tdb_new = (TDB_CONTEXT *)state;
-
-	if (tdb_store(tdb_new, key, dbuf, TDB_INSERT) != 0) {
-		fprintf(stderr,"Failed to insert into %s\n", tdb_new->name);
-		failed = 1;
-		return 1;
-	}
-	return 0;
-}
-
-
-static int test_fn(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, void *state)
-{
-	return 0;
-}
-
-/*
-  carefully backup a tdb, validating the contents and
-  only doing the backup if its OK
-  this function is also used for restore
-*/
-int backup_tdb(const char *old_name, const char *new_name)
-{
-	TDB_CONTEXT *tdb;
-	TDB_CONTEXT *tdb_new;
-	char *tmp_name;
-	struct stat st;
-	int count1, count2;
-
-	tmp_name = add_suffix(new_name, ".tmp");
-
-	/* stat the old tdb to find its permissions */
-	if (stat(old_name, &st) != 0) {
-		perror(old_name);
-		return 1;
-	}
-
-	/* open the old tdb */
-	tdb = tdb_open(old_name, 0, 0, O_RDWR, 0);
-	if (!tdb) {
-		printf("Failed to open %s\n", old_name);
-		return 1;
-	}
-
-	/* create the new tdb */
-	unlink(tmp_name);
-	tdb_new = tdb_open(tmp_name, tdb->header.hash_size, 
-			   TDB_DEFAULT, O_RDWR|O_CREAT|O_EXCL, 
-			   st.st_mode & 0777);
-	if (!tdb_new) {
-		perror(tmp_name);
-		free(tmp_name);
-		return 1;
-	}
-
-	/* lock the old tdb */
-	if (tdb_lockall(tdb) != 0) {
-		fprintf(stderr,"Failed to lock %s\n", old_name);
-		tdb_close(tdb);
-		tdb_close(tdb_new);
-		unlink(tmp_name);
-		free(tmp_name);
-		return 1;
-	}
-
-	failed = 0;
-
-	/* traverse and copy */
-	count1 = tdb_traverse(tdb, copy_fn, (void *)tdb_new);
-	if (count1 < 0 || failed) {
-		fprintf(stderr,"failed to copy %s\n", old_name);
-		tdb_close(tdb);
-		tdb_close(tdb_new);
-		unlink(tmp_name);
-		free(tmp_name);
-		return 1;
-	}
-
-	/* close the old tdb */
-	tdb_close(tdb);
-
-	/* close the new tdb and re-open read-only */
-	tdb_close(tdb_new);
-	tdb_new = tdb_open(tmp_name, 0, TDB_DEFAULT, O_RDONLY, 0);
-	if (!tdb_new) {
-		fprintf(stderr,"failed to reopen %s\n", tmp_name);
-		unlink(tmp_name);
-		perror(tmp_name);
-		free(tmp_name);
-		return 1;
-	}
-	
-	/* traverse the new tdb to confirm */
-	count2 = tdb_traverse(tdb_new, test_fn, 0);
-	if (count2 != count1) {
-		fprintf(stderr,"failed to copy %s\n", old_name);
-		tdb_close(tdb_new);
-		unlink(tmp_name);
-		free(tmp_name);
-		return 1;
-	}
-
-	/* make sure the new tdb has reached stable storage */
-	fsync(tdb_new->fd);
-
-	/* close the new tdb and rename it to .bak */
-	tdb_close(tdb_new);
-	unlink(new_name);
-	if (rename(tmp_name, new_name) != 0) {
-		perror(new_name);
-		free(tmp_name);
-		return 1;
-	}
-
-	free(tmp_name);
-
-	return 0;
-}
-
-
-
-/*
-  verify a tdb and if it is corrupt then restore from *.bak
-*/
-int verify_tdb(const char *fname, const char *bak_name)
-{
-	TDB_CONTEXT *tdb;
-	int count = -1;
-
-	/* open the tdb */
-	tdb = tdb_open(fname, 0, 0, O_RDONLY, 0);
-
-	/* traverse the tdb, then close it */
-	if (tdb) {
-		count = tdb_traverse(tdb, test_fn, NULL);
-		tdb_close(tdb);
-	}
-
-	/* count is < 0 means an error */
-	if (count < 0) {
-		printf("restoring %s\n", fname);
-		return backup_tdb(bak_name, fname);
-	}
-
-	printf("%s : %d records\n", fname, count);
-
-	return 0;
-}