2022-05-18 23:38:40

by Richard Weinberger

[permalink] [raw]
Subject: [PATCH] RFC: Reexport state database backend plugin support

Since I talked about the feature already I though it is time to show some code.

sqlite is not a perfect fit for everyone.
Especially when the re-exporting NFS server is part of a load balancer,
a more sophisticated distributed database is preferable.
This RFC patch implements support for different databases using a simple
plugin interface on top of my previous patch series.

Signed-off-by: Richard Weinberger <[email protected]>
---
support/reexport/Makefile.am | 7 +
support/reexport/backend_sqlite.c | 251 ++++++++++++++++++++++++++++
support/reexport/reexport.c | 237 +++-----------------------
support/reexport/reexport_backend.h | 48 ++++++
systemd/Makefile.am | 2 +-
systemd/nfs.conf.man | 5 +-
utils/exportd/Makefile.am | 2 +-
utils/exportfs/Makefile.am | 2 +-
utils/mount/Makefile.am | 4 +-
utils/mountd/Makefile.am | 2 +-
10 files changed, 335 insertions(+), 225 deletions(-)
create mode 100644 support/reexport/backend_sqlite.c
create mode 100644 support/reexport/reexport_backend.h

diff --git a/support/reexport/Makefile.am b/support/reexport/Makefile.am
index 9d544a8f..d45007be 100644
--- a/support/reexport/Makefile.am
+++ b/support/reexport/Makefile.am
@@ -3,4 +3,11 @@
noinst_LIBRARIES = libreexport.a
libreexport_a_SOURCES = reexport.c

+pkgplugindir=$(libdir)/libnfsreexport_backends/
+pkgplugin_LTLIBRARIES = sqlite.la
+
+sqlite_la_SOURCES = backend_sqlite.c
+sqlite_la_LDFLAGS = -module -avoid-version
+sqlite_la_LIBADD = ../../support/nfs/libnfsconf.la $(LIBSQLITE)
+
MAINTAINERCLEANFILES = Makefile.in
diff --git a/support/reexport/backend_sqlite.c b/support/reexport/backend_sqlite.c
new file mode 100644
index 00000000..a54d64ea
--- /dev/null
+++ b/support/reexport/backend_sqlite.c
@@ -0,0 +1,251 @@
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <sqlite3.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/random.h>
+#include <unistd.h>
+
+#include "conffile.h"
+#include "reexport_backend.h"
+#include "xlog.h"
+
+#define REEXPDB_DBFILE NFS_STATEDIR "/reexpdb.sqlite3"
+#define REEXPDB_DBFILE_WAIT_USEC (5000)
+
+static sqlite3 *db;
+static int init_done;
+
+static int prng_init(void)
+{
+ int seed;
+
+ if (getrandom(&seed, sizeof(seed), 0) != sizeof(seed)) {
+ xlog(L_ERROR, "Unable to obtain seed for PRNG via getrandom()");
+ return -1;
+ }
+
+ srand(seed);
+ return 0;
+}
+
+static void wait_for_dbaccess(void)
+{
+ usleep(REEXPDB_DBFILE_WAIT_USEC + (rand() % REEXPDB_DBFILE_WAIT_USEC));
+}
+
+static bool sqlite_plug_init(void)
+{
+ char *sqlerr;
+ int ret;
+
+ if (init_done)
+ return true;
+
+ if (prng_init() != 0)
+ return false;
+
+ ret = sqlite3_open_v2(conf_get_str_with_def("reexport", "sqlitedb", REEXPDB_DBFILE),
+ &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_FULLMUTEX,
+ NULL);
+ if (ret != SQLITE_OK) {
+ xlog(L_ERROR, "Unable to open reexport database: %s", sqlite3_errstr(ret));
+ return false;
+ }
+
+again:
+ ret = sqlite3_exec(db, "CREATE TABLE IF NOT EXISTS fsidnums (num INTEGER PRIMARY KEY CHECK (num > 0 AND num < 4294967296), path TEXT UNIQUE); CREATE INDEX IF NOT EXISTS idx_ids_path ON fsidnums (path);", NULL, NULL, &sqlerr);
+ switch (ret) {
+ case SQLITE_OK:
+ init_done = 1;
+ ret = 0;
+ break;
+ case SQLITE_BUSY:
+ case SQLITE_LOCKED:
+ wait_for_dbaccess();
+ goto again;
+ default:
+ xlog(L_ERROR, "Unable to init reexport database: %s", sqlite3_errstr(ret));
+ sqlite3_free(sqlerr);
+ sqlite3_close_v2(db);
+ ret = -1;
+ }
+
+ return ret == 0 ? true : false;
+}
+
+static void sqlite_plug_destroy(void)
+{
+ if (!init_done)
+ return;
+
+ sqlite3_close_v2(db);
+}
+
+static bool get_fsidnum_by_path(char *path, uint32_t *fsidnum)
+{
+ static const char fsidnum_by_path_sql[] = "SELECT num FROM fsidnums WHERE path = ?1;";
+ sqlite3_stmt *stmt = NULL;
+ bool found = false;
+ int ret;
+
+ ret = sqlite3_prepare_v2(db, fsidnum_by_path_sql, sizeof(fsidnum_by_path_sql), &stmt, NULL);
+ if (ret != SQLITE_OK) {
+ xlog(L_WARNING, "Unable to prepare SQL query '%s': %s", fsidnum_by_path_sql, sqlite3_errstr(ret));
+ goto out;
+ }
+
+ ret = sqlite3_bind_text(stmt, 1, path, -1, NULL);
+ if (ret != SQLITE_OK) {
+ xlog(L_WARNING, "Unable to bind SQL query '%s': %s", fsidnum_by_path_sql, sqlite3_errstr(ret));
+ goto out;
+ }
+
+again:
+ ret = sqlite3_step(stmt);
+ switch (ret) {
+ case SQLITE_ROW:
+ *fsidnum = sqlite3_column_int(stmt, 0);
+ found = true;
+ break;
+ case SQLITE_DONE:
+ /* No hit */
+ found = false;
+ break;
+ case SQLITE_BUSY:
+ case SQLITE_LOCKED:
+ wait_for_dbaccess();
+ goto again;
+ default:
+ xlog(L_WARNING, "Error while looking up '%s' in database: %s", path, sqlite3_errstr(ret));
+ }
+
+out:
+ sqlite3_finalize(stmt);
+ return found;
+}
+
+static bool sqlite_plug_path_by_fsidnum(uint32_t fsidnum, char **path)
+{
+ static const char path_by_fsidnum_sql[] = "SELECT path FROM fsidnums WHERE num = ?1;";
+ sqlite3_stmt *stmt = NULL;
+ bool found = false;
+ int ret;
+
+ ret = sqlite3_prepare_v2(db, path_by_fsidnum_sql, sizeof(path_by_fsidnum_sql), &stmt, NULL);
+ if (ret != SQLITE_OK) {
+ xlog(L_WARNING, "Unable to prepare SQL query '%s': %s", path_by_fsidnum_sql, sqlite3_errstr(ret));
+ goto out;
+ }
+
+ ret = sqlite3_bind_int(stmt, 1, fsidnum);
+ if (ret != SQLITE_OK) {
+ xlog(L_WARNING, "Unable to bind SQL query '%s': %s", path_by_fsidnum_sql, sqlite3_errstr(ret));
+ goto out;
+ }
+
+again:
+ ret = sqlite3_step(stmt);
+ switch (ret) {
+ case SQLITE_ROW:
+ *path = strdup((char *)sqlite3_column_text(stmt, 0));
+ if (*path)
+ found = true;
+ break;
+ case SQLITE_DONE:
+ /* No hit */
+ found = false;
+ break;
+ case SQLITE_BUSY:
+ case SQLITE_LOCKED:
+ wait_for_dbaccess();
+ goto again;
+ default:
+ xlog(L_WARNING, "Error while looking up '%i' in database: %s", fsidnum, sqlite3_errstr(ret));
+ }
+
+out:
+ sqlite3_finalize(stmt);
+ return found;
+}
+
+static bool new_fsidnum_by_path(char *path, uint32_t *fsidnum)
+{
+ /*
+ * This query is a little tricky. We use SQL to find and claim the smallest free fsid number.
+ * To find a free fsid the fsidnums is left joined to itself but with an offset of 1.
+ * Everything after the UNION statement is to handle the corner case where fsidnums
+ * is empty. In this case we want 1 as first fsid number.
+ */
+ static const char new_fsidnum_by_path_sql[] = "INSERT INTO fsidnums VALUES ((SELECT ids1.num + 1 FROM fsidnums AS ids1 LEFT JOIN fsidnums AS ids2 ON ids2.num = ids1.num + 1 WHERE ids2.num IS NULL UNION SELECT 1 WHERE NOT EXISTS (SELECT NULL FROM fsidnums WHERE num = 1) LIMIT 1), ?1) RETURNING num;";
+
+ sqlite3_stmt *stmt = NULL;
+ int ret, check = 0;
+ bool found = false;
+
+ ret = sqlite3_prepare_v2(db, new_fsidnum_by_path_sql, sizeof(new_fsidnum_by_path_sql), &stmt, NULL);
+ if (ret != SQLITE_OK) {
+ xlog(L_WARNING, "Unable to prepare SQL query '%s': %s", new_fsidnum_by_path_sql, sqlite3_errstr(ret));
+ goto out;
+ }
+
+ ret = sqlite3_bind_text(stmt, 1, path, -1, NULL);
+ if (ret != SQLITE_OK) {
+ xlog(L_WARNING, "Unable to bind SQL query '%s': %s", new_fsidnum_by_path_sql, sqlite3_errstr(ret));
+ goto out;
+ }
+
+again:
+ ret = sqlite3_step(stmt);
+ switch (ret) {
+ case SQLITE_ROW:
+ *fsidnum = sqlite3_column_int(stmt, 0);
+ found = true;
+ break;
+ case SQLITE_CONSTRAINT:
+ /* Maybe we lost the race against another writer and the path is now present. */
+ check = 1;
+ break;
+ case SQLITE_BUSY:
+ case SQLITE_LOCKED:
+ wait_for_dbaccess();
+ goto again;
+ default:
+ xlog(L_WARNING, "Error while looking up '%s' in database: %s", path, sqlite3_errstr(ret));
+ }
+
+out:
+ sqlite3_finalize(stmt);
+
+ if (check) {
+ found = get_fsidnum_by_path(path, fsidnum);
+ if (!found)
+ xlog(L_WARNING, "SQLITE_CONSTRAINT error while inserting '%s' in database", path);
+ }
+
+ return found;
+}
+
+static bool sqlite_plug_fsidnum_by_path(char *path, uint32_t *fsidnum, int may_create)
+{
+ bool found;
+
+ found = get_fsidnum_by_path(path, fsidnum);
+
+ if (!found && may_create)
+ found = new_fsidnum_by_path(path, fsidnum);
+
+ return found;
+}
+
+struct reexpdb_backend_plugin plug_ops = {
+ .fsidnum_by_path = sqlite_plug_fsidnum_by_path,
+ .path_by_fsidnum = sqlite_plug_path_by_fsidnum,
+ .initdb = sqlite_plug_init,
+ .destroydb = sqlite_plug_destroy,
+};
+
diff --git a/support/reexport/reexport.c b/support/reexport/reexport.c
index 61574fc5..112fcfb9 100644
--- a/support/reexport/reexport.c
+++ b/support/reexport/reexport.c
@@ -2,7 +2,7 @@
#include <config.h>
#endif

-#include <sqlite3.h>
+#include <dlfcn.h>
#include <stdint.h>
#include <stdio.h>
#include <sys/random.h>
@@ -15,228 +15,38 @@
#include "conffile.h"
#include "nfslib.h"
#include "reexport.h"
+#include "reexport_backend.h"
#include "xcommon.h"
#include "xlog.h"

-#define REEXPDB_DBFILE NFS_STATEDIR "/reexpdb.sqlite3"
-#define REEXPDB_DBFILE_WAIT_USEC (5000)
+struct reexpdb_backend_plugin *plg;
+static void *backend_dl;

-static sqlite3 *db;
-static int init_done;
-
-static int prng_init(void)
-{
- int seed;
-
- if (getrandom(&seed, sizeof(seed), 0) != sizeof(seed)) {
- xlog(L_ERROR, "Unable to obtain seed for PRNG via getrandom()");
- return -1;
- }
-
- srand(seed);
- return 0;
-}
-
-static void wait_for_dbaccess(void)
-{
- usleep(REEXPDB_DBFILE_WAIT_USEC + (rand() % REEXPDB_DBFILE_WAIT_USEC));
-}
-
-/*
- * reexpdb_init - Initialize reexport database
- */
int reexpdb_init(void)
{
- char *sqlerr;
- int ret;
-
- if (init_done)
- return 0;
+ char *sofile = conf_get_str_with_def("reexport", "backend_plugin", REEXPDB_BACKEND_DEFAULT);

- if (prng_init() != 0)
- return -1;
-
- ret = sqlite3_open_v2(conf_get_str_with_def("reexport", "sqlitedb", REEXPDB_DBFILE),
- &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_FULLMUTEX,
- NULL);
- if (ret != SQLITE_OK) {
- xlog(L_ERROR, "Unable to open reexport database: %s", sqlite3_errstr(ret));
+ backend_dl = dlopen(sofile, RTLD_NOW | RTLD_LOCAL);
+ if (!backend_dl) {
+ xlog(L_WARNING, "Unable to open %s: %s", sofile, dlerror());
return -1;
}

-again:
- ret = sqlite3_exec(db, "CREATE TABLE IF NOT EXISTS fsidnums (num INTEGER PRIMARY KEY CHECK (num > 0 AND num < 4294967296), path TEXT UNIQUE); CREATE INDEX IF NOT EXISTS idx_ids_path ON fsidnums (path);", NULL, NULL, &sqlerr);
- switch (ret) {
- case SQLITE_OK:
- init_done = 1;
- ret = 0;
- break;
- case SQLITE_BUSY:
- case SQLITE_LOCKED:
- wait_for_dbaccess();
- goto again;
- default:
- xlog(L_ERROR, "Unable to init reexport database: %s", sqlite3_errstr(ret));
- sqlite3_free(sqlerr);
- sqlite3_close_v2(db);
- ret = -1;
+ plg = (struct reexpdb_backend_plugin *)dlsym(backend_dl, REEXPDB_BACKEND_OPS);
+ if (plg == NULL) {
+ xlog(L_WARNING, "Unable to locate plug_ops in %s: %s", sofile, dlerror());
+ dlclose(backend_dl);
+ return -1;
}

- return ret;
+ return plg->initdb() == true;
}

-/*
- * reexpdb_destroy - Undo reexpdb_init().
- */
void reexpdb_destroy(void)
{
- if (!init_done)
- return;
-
- sqlite3_close_v2(db);
-}
-
-static int get_fsidnum_by_path(char *path, uint32_t *fsidnum)
-{
- static const char fsidnum_by_path_sql[] = "SELECT num FROM fsidnums WHERE path = ?1;";
- sqlite3_stmt *stmt = NULL;
- int found = 0;
- int ret;
-
- ret = sqlite3_prepare_v2(db, fsidnum_by_path_sql, sizeof(fsidnum_by_path_sql), &stmt, NULL);
- if (ret != SQLITE_OK) {
- xlog(L_WARNING, "Unable to prepare SQL query '%s': %s", fsidnum_by_path_sql, sqlite3_errstr(ret));
- goto out;
- }
-
- ret = sqlite3_bind_text(stmt, 1, path, -1, NULL);
- if (ret != SQLITE_OK) {
- xlog(L_WARNING, "Unable to bind SQL query '%s': %s", fsidnum_by_path_sql, sqlite3_errstr(ret));
- goto out;
- }
-
-again:
- ret = sqlite3_step(stmt);
- switch (ret) {
- case SQLITE_ROW:
- *fsidnum = sqlite3_column_int(stmt, 0);
- found = 1;
- break;
- case SQLITE_DONE:
- /* No hit */
- found = 0;
- break;
- case SQLITE_BUSY:
- case SQLITE_LOCKED:
- wait_for_dbaccess();
- goto again;
- default:
- xlog(L_WARNING, "Error while looking up '%s' in database: %s", path, sqlite3_errstr(ret));
- }
-
-out:
- sqlite3_finalize(stmt);
- return found;
-}
-
-static int get_path_by_fsidnum(uint32_t fsidnum, char **path)
-{
- static const char path_by_fsidnum_sql[] = "SELECT path FROM fsidnums WHERE num = ?1;";
- sqlite3_stmt *stmt = NULL;
- int found = 0;
- int ret;
-
- ret = sqlite3_prepare_v2(db, path_by_fsidnum_sql, sizeof(path_by_fsidnum_sql), &stmt, NULL);
- if (ret != SQLITE_OK) {
- xlog(L_WARNING, "Unable to prepare SQL query '%s': %s", path_by_fsidnum_sql, sqlite3_errstr(ret));
- goto out;
- }
-
- ret = sqlite3_bind_int(stmt, 1, fsidnum);
- if (ret != SQLITE_OK) {
- xlog(L_WARNING, "Unable to bind SQL query '%s': %s", path_by_fsidnum_sql, sqlite3_errstr(ret));
- goto out;
- }
-
-again:
- ret = sqlite3_step(stmt);
- switch (ret) {
- case SQLITE_ROW:
- *path = xstrdup((char *)sqlite3_column_text(stmt, 0));
- found = 1;
- break;
- case SQLITE_DONE:
- /* No hit */
- found = 0;
- break;
- case SQLITE_BUSY:
- case SQLITE_LOCKED:
- wait_for_dbaccess();
- goto again;
- default:
- xlog(L_WARNING, "Error while looking up '%i' in database: %s", fsidnum, sqlite3_errstr(ret));
- }
-
-out:
- sqlite3_finalize(stmt);
- return found;
-}
-
-static int new_fsidnum_by_path(char *path, uint32_t *fsidnum)
-{
- /*
- * This query is a little tricky. We use SQL to find and claim the smallest free fsid number.
- * To find a free fsid the fsidnums is left joined to itself but with an offset of 1.
- * Everything after the UNION statement is to handle the corner case where fsidnums
- * is empty. In this case we want 1 as first fsid number.
- */
- static const char new_fsidnum_by_path_sql[] = "INSERT INTO fsidnums VALUES ((SELECT ids1.num + 1 FROM fsidnums AS ids1 LEFT JOIN fsidnums AS ids2 ON ids2.num = ids1.num + 1 WHERE ids2.num IS NULL UNION SELECT 1 WHERE NOT EXISTS (SELECT NULL FROM fsidnums WHERE num = 1) LIMIT 1), ?1) RETURNING num;";
-
- sqlite3_stmt *stmt = NULL;
- int found = 0, check = 0;
- int ret;
-
- ret = sqlite3_prepare_v2(db, new_fsidnum_by_path_sql, sizeof(new_fsidnum_by_path_sql), &stmt, NULL);
- if (ret != SQLITE_OK) {
- xlog(L_WARNING, "Unable to prepare SQL query '%s': %s", new_fsidnum_by_path_sql, sqlite3_errstr(ret));
- goto out;
- }
-
- ret = sqlite3_bind_text(stmt, 1, path, -1, NULL);
- if (ret != SQLITE_OK) {
- xlog(L_WARNING, "Unable to bind SQL query '%s': %s", new_fsidnum_by_path_sql, sqlite3_errstr(ret));
- goto out;
- }
-
-again:
- ret = sqlite3_step(stmt);
- switch (ret) {
- case SQLITE_ROW:
- *fsidnum = sqlite3_column_int(stmt, 0);
- found = 1;
- break;
- case SQLITE_CONSTRAINT:
- /* Maybe we lost the race against another writer and the path is now present. */
- check = 1;
- break;
- case SQLITE_BUSY:
- case SQLITE_LOCKED:
- wait_for_dbaccess();
- goto again;
- default:
- xlog(L_WARNING, "Error while looking up '%s' in database: %s", path, sqlite3_errstr(ret));
- }
-
-out:
- sqlite3_finalize(stmt);
-
- if (check) {
- found = get_fsidnum_by_path(path, fsidnum);
- if (!found)
- xlog(L_WARNING, "SQLITE_CONSTRAINT error while inserting '%s' in database", path);
- }
-
- return found;
+ plg->destroydb();
+ plg = NULL;
+ dlclose(backend_dl);
}

/*
@@ -249,14 +59,7 @@ out:
*/
int reexpdb_fsidnum_by_path(char *path, uint32_t *fsidnum, int may_create)
{
- int found;
-
- found = get_fsidnum_by_path(path, fsidnum);
-
- if (!found && may_create)
- found = new_fsidnum_by_path(path, fsidnum);
-
- return found;
+ return plg->fsidnum_by_path(path, fsidnum, may_create);
}

/*
@@ -278,7 +81,7 @@ void reexpdb_uncover_subvolume(uint32_t fsidnum)
char *path = NULL;
int ret;

- if (get_path_by_fsidnum(fsidnum, &path)) {
+ if (plg->path_by_fsidnum(fsidnum, &path)) {
ret = nfsd_path_statfs64(path, &st);
if (ret == -1)
xlog(L_WARNING, "statfs() failed");
@@ -300,7 +103,7 @@ void reexpdb_uncover_subvolume(uint32_t fsidnum)
int reexpdb_apply_reexport_settings(struct exportent *ep, char *flname, int flline)
{
uint32_t fsidnum;
- int found;
+ bool found;
int ret = 0;

if (ep->e_reexport == REEXP_NONE)
diff --git a/support/reexport/reexport_backend.h b/support/reexport/reexport_backend.h
new file mode 100644
index 00000000..9e5e5c43
--- /dev/null
+++ b/support/reexport/reexport_backend.h
@@ -0,0 +1,48 @@
+#ifndef REEXPORT_BACKEND_H
+#define REEXPORT_BACKEND_H
+
+#define REEXPDB_BACKEND_DEFAULT "sqlite.so"
+#define REEXPDB_BACKEND_OPS "plug_ops"
+
+struct reexpdb_backend_plugin {
+ /*
+ * Find or allocate a fsidnum for a given path.
+ *
+ * @path: Path to look for
+ * @fsidnum: Pointer to an uint32_t variable
+ * @may_create: If non-zero, a fsidnum will be allocated if none was found
+ *
+ * Returns true if either an fsidnum was found or successfully allocated,
+ * false otherwise.
+ * On success, the fsidnum will be stored into @fsidnum.
+ * Upon errors, false is returned and errors are logged.
+ */
+ bool (*fsidnum_by_path)(char *path, uint32_t *fsidnum, int may_create);
+
+ /*
+ * Lookup path by a given fsidnum
+ *
+ * @fsidnum: fsidnum to look for
+ * @path: address of a char pointer
+ *
+ * Returns true if a path was found, false otherwise.
+ * Upon errors, false is returned and errors are logged.
+ * In case of success, the function returns the found path
+ * via @path, @path will point to a freshly allocated buffer
+ * which is free()'able.
+ */
+ bool (*path_by_fsidnum)(uint32_t fsidnum, char **path);
+
+ /*
+ * Init database connection, can get called multiple times.
+ * Returns true on success, false otherwise.
+ */
+ bool (*initdb)(void);
+
+ /*
+ * Undoes initdb().
+ */
+ void (*destroydb)(void);
+};
+
+#endif /* REEXPORT_BACKEND_H */
diff --git a/systemd/Makefile.am b/systemd/Makefile.am
index f254b218..70182600 100644
--- a/systemd/Makefile.am
+++ b/systemd/Makefile.am
@@ -70,7 +70,7 @@ nfs_server_generator_LDADD = ../support/export/libexport.a \
$(LIBPTHREAD)

if CONFIG_REEXPORT
-nfs_server_generator_LDADD += ../support/reexport/libreexport.a $(LIBSQLITE) -lrt
+nfs_server_generator_LDADD += ../support/reexport/libreexport.a -ldl
endif

rpc_pipefs_generator_LDADD = ../support/nfs/libnfs.la
diff --git a/systemd/nfs.conf.man b/systemd/nfs.conf.man
index afd2b3f8..0d083171 100644
--- a/systemd/nfs.conf.man
+++ b/systemd/nfs.conf.man
@@ -297,9 +297,10 @@ is recognized.

.TP
.B reexport
-Only
.B sqlitedb=
-is recognized, path to the state database.
+, path to the state database, if sqlite backend is used.
+.B backend_plugin=
+, path to database backend plugin, default is sqlite.so.

.SH FILES
.TP 10n
diff --git a/utils/exportd/Makefile.am b/utils/exportd/Makefile.am
index b0ec9034..6f23ed97 100644
--- a/utils/exportd/Makefile.am
+++ b/utils/exportd/Makefile.am
@@ -19,7 +19,7 @@ exportd_LDADD = ../../support/export/libexport.a \
$(OPTLIBS) $(LIBBLKID) $(LIBPTHREAD) \
-luuid
if CONFIG_REEXPORT
-exportd_LDADD += ../../support/reexport/libreexport.a $(LIBSQLITE) -lrt
+exportd_LDADD += ../../support/reexport/libreexport.a -ldl
endif

exportd_CPPFLAGS = $(AM_CPPFLAGS) $(CPPFLAGS) \
diff --git a/utils/exportfs/Makefile.am b/utils/exportfs/Makefile.am
index 451637a0..a17ed130 100644
--- a/utils/exportfs/Makefile.am
+++ b/utils/exportfs/Makefile.am
@@ -13,7 +13,7 @@ exportfs_LDADD = ../../support/export/libexport.a \
$(LIBWRAP) $(LIBNSL) $(LIBPTHREAD)

if CONFIG_REEXPORT
-exportfs_LDADD += ../../support/reexport/libreexport.a $(LIBSQLITE) -lrt
+exportfs_LDADD += ../../support/reexport/libreexport.a -ldl
endif

exportfs_CPPFLAGS = $(AM_CPPFLAGS) $(CPPFLAGS) -I$(top_srcdir)/support/reexport
diff --git a/utils/mount/Makefile.am b/utils/mount/Makefile.am
index 0268488c..d569b127 100644
--- a/utils/mount/Makefile.am
+++ b/utils/mount/Makefile.am
@@ -33,9 +33,9 @@ mount_nfs_LDADD = ../../support/nfs/libnfs.la \
$(LIBTIRPC)

if CONFIG_REEXPORT
-mount_nfs_LDADD += ../../support/reexport/libreexport.a \
+mount_nfs_LDADD += ../../support/reexport/libreexport.a -ldl \
../../support/misc/libmisc.a \
- $(LIBSQLITE) -lrt $(LIBPTHREAD)
+ -lrt $(LIBPTHREAD)
endif


diff --git a/utils/mountd/Makefile.am b/utils/mountd/Makefile.am
index 569d335a..d9a5c374 100644
--- a/utils/mountd/Makefile.am
+++ b/utils/mountd/Makefile.am
@@ -21,7 +21,7 @@ mountd_LDADD = ../../support/export/libexport.a \
$(LIBBSD) $(LIBWRAP) $(LIBNSL) $(LIBBLKID) -luuid $(LIBTIRPC) \
$(LIBPTHREAD)
if CONFIG_REEXPORT
-mountd_LDADD += ../../support/reexport/libreexport.a $(LIBSQLITE) -lrt
+mountd_LDADD += ../../support/reexport/libreexport.a -ldl
endif

mountd_CPPFLAGS = $(AM_CPPFLAGS) $(CPPFLAGS) \
--
2.31.1