This patch allows to link mount.nfs with libmount from util-linux >=
v2.19. The new libmount based code is enabled by CONFIG_LIBMOUNT and
is stored in mount_libmount.c. The old code is not affected by this
change.
The libmount does not have officially stable API yet, so the
--enable-libmount-mount is marked as experimental in the configure
help output.
The ./configure option is the same as we use in util-linux to enable
support for libmount in mount(8).
The addr= (and some other options necessary for remount/umount) are
stored to /etc/mtab or to /dev/.mount/utab. The utab file is *private*
libmount file. It's possible that some mount options (for example
user=) will be moved to kernel, so the utab will not be necessary.
About libmount:
* supports systems without and with regular /etc/mtab
* does not store VFS and FS mount options in userspace
* manages user= option and evaluate permissions
* parses VFS mount options and generate MS_* flags
* parses /etc/{fstab,mtab}, /proc/mounts or /proc/self/mountinfo
* long-term goal is to use the same code in all mount.<type> helpers
Note, use
LIBMOUNT_DEBUG=0xffff mount.nfs foo:/path /path
to debug the library.
On systems with util-linux v2.19 the findmnt(8) command uses libmount
to list all/selected mount points:
$ findmnt /path
$ findmnt --mtab /path
the --mtab appends userspace mount options (e.g. user=) to the output.
CC: Chuck Lever <chuck.lever@xxxxxxxxxx>
CC: Steve Dickson <steved@xxxxxxxxxx>
Signed-off-by: Karel Zak <kzak@xxxxxxxxxx>
---
configure.ac | 16 ++
utils/mount/Makefile.am | 13 +-
utils/mount/mount_libmount.c | 413 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 440 insertions(+), 2 deletions(-)
create mode 100644 utils/mount/mount_libmount.c
diff --git a/configure.ac b/configure.ac
index 2e074d9..9c384d8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -132,6 +132,15 @@ AC_ARG_ENABLE(mount,
enable_mount=$enableval,
enable_mount=yes)
AM_CONDITIONAL(CONFIG_MOUNT, [test "$enable_mount" = "yes"])
+
+if test "$enable_mount" = yes; then
+ AC_ARG_ENABLE(libmount-mount,
+ [AC_HELP_STRING([--enable-libmount-mount],
+ [Link mount.nfs with libmount (EXPERIMENTAL)])],
+ enable_libmount=yes,
+ enable_libmount=no)
+fi
+
AC_ARG_ENABLE(tirpc,
[AC_HELP_STRING([--enable-tirpc],
[enable use of TI-RPC @<:@default=yes@:>@])],
@@ -285,6 +294,13 @@ AC_SUBST(LIBCRYPT)
AC_SUBST(LIBBSD)
AC_SUBST(LIBBLKID)
+if test "$enable_libmount" != no; then
+ AC_CHECK_LIB(mount, mnt_context_do_mount, [LIBMOUNT="-lmount"], AC_MSG_ERROR([libmount needed]))
+ AC_CHECK_HEADER(libmount/libmount.h, , AC_MSG_ERROR([Cannot find libmount header file libmount/libmount.h]))
+fi
+AM_CONDITIONAL(CONFIG_LIBMOUNT, [test "$enable_libmount" = "yes"])
+AC_SUBST(LIBMOUNT)
+
if test "$enable_gss" = yes; then
dnl 'gss' requires getnameinfo - at least for gssd_proc.c
AC_CHECK_FUNC([getnameinfo], , [AC_MSG_ERROR([GSSAPI support requires 'getnameinfo' function])])
diff --git a/utils/mount/Makefile.am b/utils/mount/Makefile.am
index a9553dc..056293c 100644
--- a/utils/mount/Makefile.am
+++ b/utils/mount/Makefile.am
@@ -9,7 +9,7 @@ man5_MANS = nfs.man
sbin_PROGRAMS = mount.nfs
EXTRA_DIST = nfsmount.x $(man8_MANS) $(man5_MANS)
-mount_nfs_SOURCES = mount.c error.c network.c fstab.c token.c \
+mount_common = error.c network.c fstab.c token.c \
parse_opt.c parse_dev.c \
nfsmount.c nfs4mount.c stropts.c\
nfsumount.c \
@@ -19,7 +19,7 @@ mount_nfs_SOURCES = mount.c error.c network.c fstab.c token.c \
mount_config.h utils.c utils.h
if MOUNT_CONFIG
-mount_nfs_SOURCES += configfile.c
+mount_common += configfile.c
man5_MANS += nfsmount.conf.man
EXTRA_DIST += nfsmount.conf
endif
@@ -27,6 +27,15 @@ endif
mount_nfs_LDADD = ../../support/nfs/libnfs.a \
../../support/export/libexport.a
+mount_nfs_SOURCES = $(mount_common)
+
+if CONFIG_LIBMOUNT
+mount_nfs_SOURCES += mount_libmount.c
+mount_nfs_LDADD += $(LIBMOUNT)
+else
+mount_nfs_SOURCES += mount.c
+endif
+
MAINTAINERCLEANFILES = Makefile.in
install-exec-hook:
diff --git a/utils/mount/mount_libmount.c b/utils/mount/mount_libmount.c
new file mode 100644
index 0000000..6dd6484
--- /dev/null
+++ b/utils/mount/mount_libmount.c
@@ -0,0 +1,413 @@
+/*
+ * mount_libmount.c -- Linux NFS [u]mount based on libmount
+ *
+ * Copyright (C) 2011 Karel Zak <kzak@xxxxxxxxxx>
+ *
+ * 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, 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., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <getopt.h>
+
+#include <libmount/libmount.h>
+
+#include "nls.h"
+#include "mount_config.h"
+
+#include "nfs_mount.h"
+#include "nfs4_mount.h"
+#include "stropts.h"
+#include "version.h"
+#include "xcommon.h"
+
+#include "error.h"
+#include "utils.h"
+
+char *progname;
+int nfs_mount_data_version;
+int verbose;
+int sloppy;
+int string;
+int nomtab;
+
+#define FOREGROUND (0)
+#define BACKGROUND (1)
+
+/*
+ * Store mount options to mtab (or /dev/.mount/utab), called from mount.nfs.
+ *
+ * Note that on systems without /etc/mtab the fs-specific options are not
+ * managed by libmount at all. We have to use "mount attributes" that are
+ * private for mount.<type> helpers.
+ */
+static void store_mount_options(struct libmnt_fs *fs, const char *opts)
+{
+ mnt_fs_set_fs_options(fs, opts); /* for mtab */
+ mnt_fs_set_attributes(fs, opts); /* for non-mtab systems */
+}
+
+/*
+ * Retrieve mount options from mtab (or /dev/.mount/utab) called from umount.nfs.
+ *
+ * The result can passed to free().
+ */
+char *retrieve_mount_options(struct libmnt_fs *fs)
+{
+ const char *opts;
+
+ if (!fs)
+ return NULL;
+
+ opts = mnt_fs_get_attributes(fs); /* /dev/.mount/utab */
+ if (opts)
+ return strdup(opts);
+
+ return mnt_fs_strdup_options(fs); /* /etc/mtab */
+}
+
+static int try_mount(struct libmnt_context *cxt, int bg)
+{
+ struct libmnt_fs *fs;
+ const char *p;
+ char *src = NULL, *tgt = NULL, *type = NULL, *opts = NULL;
+ unsigned long flags = 0;
+ int fake, ret = 0;
+
+ fs = mnt_context_get_fs(cxt);
+
+ /* libmount returns read-only pointers (const char)
+ * so, reallocate for nfsmount() functions.
+ */
+ if ((p = mnt_fs_get_source(fs))) /* spec */
+ src = strdup(p);
+ if ((p = mnt_fs_get_target(fs))) /* mountpoint */
+ tgt = strdup(p);
+ if ((p = mnt_fs_get_fstype(fs))) /* FS type */
+ type = strdup(p);
+ if ((p = mnt_fs_get_fs_options(fs))) /* mount options */
+ opts = strdup(p);
+
+ mnt_context_get_mflags(cxt, &flags); /* mount(2) flags */
+ fake = mnt_context_is_fake(cxt);
+
+ if (string)
+ ret = nfsmount_string(src, tgt, type, flags, &opts, fake, bg);
+
+ else if (strcmp(type, "nfs4") == 0)
+ ret = nfs4mount(src, tgt, flags, &opts, fake, bg);
+ else
+ ret = nfsmount(src, tgt, flags, &opts, fake, bg);
+
+ /* Store mount options if not called with mount --no-mtab */
+ if (!ret && !mnt_context_is_nomtab(cxt))
+ store_mount_options(fs, opts);
+
+ free(src);
+ free(tgt);
+ free(type);
+ free(opts);
+
+ return ret;
+}
+
+/* returns: error = -1, success = 0 , unknown = 1 */
+static int is_vers4(struct libmnt_context *cxt)
+{
+ struct libmnt_fs *fs = mnt_context_get_fs(cxt);
+ struct libmnt_table *tb = NULL;
+ const char *src = mnt_context_get_source(cxt),
+ *tgt = mnt_context_get_target(cxt);
+ int rc = 1;
+
+ if (!src || !tgt)
+ return -1;
+
+ if (!mnt_fs_is_kernel(fs)) {
+ struct libmnt_table *tb = mnt_new_table_from_file("/proc/mounts");
+
+ if (!tb)
+ return -1;
+ fs = mnt_table_find_pair(tb, src, tgt, MNT_ITER_BACKWARD);
+ }
+
+ if (fs) {
+ const char *type = mnt_fs_get_fstype(fs);
+ if (type && strcmp(type, "nfs4") == 0)
+ rc = 0;
+ }
+ mnt_free_table(tb);
+ return rc;
+}
+
+static int umount_main(struct libmnt_context *cxt, int argc, char **argv)
+{
+ int rc, c;
+ char *spec = NULL, *opts = NULL;
+
+ static const struct option longopts[] = {
+ { "force", 0, 0, 'f' },
+ { "help", 0, 0, 'h' },
+ { "no-mtab", 0, 0, 'n' },
+ { "verbose", 0, 0, 'v' },
+ { "read-only", 0, 0, 'r' },
+ { "lazy", 0, 0, 'l' },
+ { "types", 1, 0, 't' },
+ { NULL, 0, 0, 0 }
+ };
+
+ mnt_context_init_helper(cxt, MNT_ACT_UMOUNT, 0);
+
+ while ((c = getopt_long (argc, argv, "fvnrlh", longopts, NULL)) != -1) {
+
+ rc = mnt_context_helper_setopt(cxt, c, optarg);
+ if (rc == 0) /* valid option */
+ continue;
+ if (rc < 0) /* error (probably ENOMEM) */
+ goto err;
+ /* rc==1 means unknow option */
+ umount_usage();
+ return EX_USAGE;
+ }
+
+ if (optind < argc)
+ spec = argv[optind++];
+
+ if (!spec || (*spec != '/' && strchr(spec,':') == NULL)) {
+ nfs_error(_("%s: no mount point provided"), progname);
+ return EX_USAGE;
+ }
+
+ if (mnt_context_set_target(cxt, spec))
+ goto err;
+ if (mnt_context_set_fstype_pattern(cxt, "nfs,nfs4")) /* restrict filesystems */
+ goto err;
+
+ /* read mtab/fstab, evaluate permissions, etc. */
+ rc = mnt_context_prepare_umount(cxt);
+ if (rc) {
+ nfs_error(_("%s: failed to prepare umount: %s\n"),
+ progname, strerror(-rc));
+ goto err;
+ }
+
+ opts = retrieve_mount_options(mnt_context_get_fs(cxt));
+
+ if (!mnt_context_is_lazy(cxt)) {
+ if (opts) {
+ /* we have full FS description (e.g. from mtab or /proc) */
+ switch (is_vers4(cxt)) {
+ case 0:
+ /* We ignore the error from nfs_umount23.
+ * If the actual umount succeeds (in del_mtab),
+ * we don't want to signal an error, as that
+ * could cause /sbin/mount to retry!
+ */
+ nfs_umount23(mnt_context_get_source(cxt), opts);
+ break;
+ case 1: /* unknown */
+ break;
+ default: /* error */
+ goto err;
+ }
+ } else
+ /* strange, no entry in mtab or /proc not mounted */
+ nfs_umount23(spec, "tcp,v3");
+ }
+
+ rc = mnt_context_do_umount(cxt); /* call umount(2) syscall */
+ mnt_context_finalize_mount(cxt); /* mtab update */
+
+ if (rc && !mnt_context_get_status(cxt)) {
+ /* mnt_context_do_umount() returns errno if umount(2) failed */
+ umount_error(rc, spec);
+ goto err;
+ }
+
+ free(opts);
+ return EX_SUCCESS;
+err:
+ free(opts);
+ return EX_FAIL;
+}
+
+static int mount_main(struct libmnt_context *cxt, int argc, char **argv)
+{
+ int rc, c;
+ struct libmnt_fs *fs;
+ char *spec = NULL, *mount_point = NULL, *opts = NULL;
+
+ static const struct option longopts[] = {
+ { "fake", 0, 0, 'f' },
+ { "help", 0, 0, 'h' },
+ { "no-mtab", 0, 0, 'n' },
+ { "read-only", 0, 0, 'r' },
+ { "ro", 0, 0, 'r' },
+ { "verbose", 0, 0, 'v' },
+ { "version", 0, 0, 'V' },
+ { "read-write", 0, 0, 'w' },
+ { "rw", 0, 0, 'w' },
+ { "options", 1, 0, 'o' },
+ { "sloppy", 0, 0, 's' },
+ { NULL, 0, 0, 0 }
+ };
+
+ mount_config_init(progname);
+ mnt_context_init_helper(cxt, MNT_ACT_MOUNT, 0);
+
+ while ((c = getopt_long(argc, argv, "fhnrVvwo:s", longopts, NULL)) != -1) {
+
+ rc = mnt_context_helper_setopt(cxt, c, optarg);
+ if (rc == 0) /* valid option */
+ continue;
+ if (rc < 0) /* error (probably ENOMEM) */
+ goto err;
+ /* rc==1 means unknow option */
+ switch (c) {
+ case 'V':
+ printf("%s: ("PACKAGE_STRING")\n", progname);
+ return EX_SUCCESS;
+ case 'h':
+ default:
+ mount_usage();
+ return EX_USAGE;
+ }
+ }
+
+ if (optind < argc)
+ spec = argv[optind++];
+ if (optind < argc)
+ mount_point = argv[optind++];
+
+ if (!mount_point) {
+ nfs_error(_("%s: no mount point provided"), progname);
+ goto err;
+ }
+ if (!spec) {
+ nfs_error(_("%s: no mount spec provided"), progname);
+ goto err;
+ }
+
+ if (geteuid() != 0) {
+ nfs_error(_("%s: not installed setuid - "
+ "\"user\" NFS mounts not supported."), progname);
+ goto err;
+ }
+
+ verbose = mnt_context_is_verbose(cxt);
+ sloppy = mnt_context_is_sloppy(cxt);
+ nomtab = mnt_context_is_nomtab(cxt);
+
+ if (strcmp(progname, "mount.nfs4") == 0)
+ mnt_context_set_fstype(cxt, "nfs4");
+ else
+ mnt_context_set_fstype(cxt, "nfs"); /* default */
+
+ rc = mnt_context_set_source(cxt, spec);
+ if (!rc)
+ mnt_context_set_target(cxt, mount_point);
+ if (rc) {
+ nfs_error(_("%s: failed to set spec or mountpoint: %s"),
+ progname, strerror(errno));
+ goto err;
+ }
+
+ mount_point = mnt_resolve_path(mount_point,
+ mnt_context_get_cache(cxt));
+
+ if (chk_mountpoint(mount_point))
+ goto err;
+ /*
+ * Concatenate mount options from the configuration file
+ */
+ fs = mnt_context_get_fs(cxt);
+ if (fs) {
+ opts = mnt_fs_strdup_options(fs);
+
+ opts = mount_config_opts(spec, mount_point, opts);
+ mnt_fs_set_options(fs, opts);
+ }
+
+ rc = mnt_context_prepare_mount(cxt);
+ if (rc) {
+ nfs_error(_("%s: failed to prepare mount: %s\n"),
+ progname, strerror(-rc));
+ goto err;
+ }
+
+ rc = try_mount(cxt, FOREGROUND);
+
+ if (rc == EX_BG) {
+ printf(_("%s: backgrounding \"%s\"\n"),
+ progname, mnt_context_get_source(cxt));
+ printf(_("%s: mount options: \"%s\"\n"),
+ progname, opts);
+
+ fflush(stdout);
+
+ if (daemon(0, 0)) {
+ nfs_error(_("%s: failed to start "
+ "background process: %s\n"),
+ progname, strerror(errno));
+ exit(EX_FAIL);
+ }
+
+ rc = try_mount(cxt, BACKGROUND);
+
+ if (verbose && rc)
+ printf(_("%s: giving up \"%s\"\n"),
+ progname, mnt_context_get_source(cxt));
+ }
+
+ mnt_context_set_syscall_status(cxt, rc == EX_SUCCESS ? 0 : -1);
+ mnt_context_finalize_mount(cxt); /* mtab update */
+ return rc;
+err:
+ return EX_FAIL;
+}
+
+int main(int argc, char *argv[])
+{
+ struct libmnt_context *cxt;
+ int rc;
+
+ mnt_init_debug(0);
+ cxt = mnt_new_context();
+ if (!cxt) {
+ nfs_error(_("Can't initilize libmount: %s"),
+ strerror(errno));
+ rc = EX_FAIL;
+ goto done;
+ }
+
+ progname = basename(argv[0]);
+ nfs_mount_data_version = discover_nfs_mount_data_version(&string);
+
+ if(strncmp(progname, "umount", 6) == 0)
+ rc = umount_main(cxt, argc, argv);
+ else
+ rc = mount_main(cxt, argc, argv);
+done:
+ mnt_free_context(cxt);
+ return rc;
+}
--
1.7.3.4
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