From 9f103625b145a397e67c3714766775b615c8b587 Mon Sep 17 00:00:00 2001
From: Tobias Hunger <tobias.hunger@gmail.com>
Date: Thu, 9 Oct 2014 21:37:17 +0200
Subject: [PATCH] fstab-generator: Honor mount.usr*= on kernel command line
This allows to configure boot loader entries for systems where the
root and usr filesystems are in different subvolumes (or even on
different drives).
---
man/systemd-fstab-generator.xml | 76 ++++++++++++++++++++++++++++-
src/fstab-generator/fstab-generator.c | 90 +++++++++++++++++++++++++++++++++--
2 files changed, 160 insertions(+), 6 deletions(-)
diff --git a/man/systemd-fstab-generator.xml b/man/systemd-fstab-generator.xml
index e3cf5d2bfb..65b48eea07 100644
--- a/man/systemd-fstab-generator.xml
+++ b/man/systemd-fstab-generator.xml
@@ -104,9 +104,83 @@
(initrd) while
<varname>fstab=</varname> is
honored by both the main system and
- the initrd. </para></listitem>
+ the initrd.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>root=</varname></term>
+
+ <listitem><para>Takes the root filesystem to mount
+ in the initrd.
+ <varname>root=</varname> is
+ honored by the initrd.</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><varname>rootfstype=</varname></term>
+
+ <listitem><para>Takes the root filesystem type that
+ will be passed to the mount command.
+ <varname>rootfstype=</varname> is
+ honored by the initrd.</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><varname>rootflags=</varname></term>
+
+ <listitem><para>Takes the root filesystem mount options
+ to use. <varname>rootflags=</varname> is
+ honored by the initrd.</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><varname>mount.usr=</varname></term>
+
+ <listitem><para>Takes the <filename>/usr</filename>
+ filesystem to be mounted by the initrd. If
+ <varname>mount.usrfstype=</varname> or
+ <varname>mount.usrflags=</varname> is set, then
+ <varname>mount.usr=</varname> will default to the value set in
+ <varname>root=</varname>.</para>
+
+ <para>Otherwise this parameter defaults to the
+ <filename>/usr</filename> entry
+ found in <filename>/etc/fstab</filename> on the root
+ filesystem.</para>
+
+ <para><varname>mount.usr=</varname> is honored by the initrd.
+ </para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><varname>mount.usrfstype=</varname></term>
+
+ <listitem><para>Takes the <filename>/usr</filename>
+ filesystem type that will be passed to the mount
+ command. If <varname>mount.usr=</varname> or
+ <varname>mount.usrflags=</varname> is set, then
+ <varname>mount.usrfstype=</varname> will default to the value set in
+ <varname>rootfstype=</varname>.</para>
+
+ <para>Otherwise this value will be read from the
+ <filename>/usr</filename> entry in
+ <filename>/etc/fstab</filename> on the root filesystem.</para>
+
+ <para><varname>mount.usrfstype=</varname> is
+ honored by the initrd.</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><varname>mount.usrflags=</varname></term>
+
+ <listitem><para>Takes the <filename>/usr</filename>
+ filesystem mount options to use. If
+ <varname>mount.usr=</varname> or
+ <varname>mount.usrfstype=</varname> is set, then
+ <varname>mount.usrflages=</varname> will default to the value set in
+ <varname>rootflags=</varname>.</para>
+ <para>Otherwise this value will be read from the
+ <filename>/usr</filename> entry in
+ <filename>/etc/fstab</filename> on the root filesystem.</para>
+
+ <para><varname>mount.usrflags=</varname> is
+ honored by the initrd.</para></listitem>
+ </varlistentry>
</variablelist>
</refsect1>
diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index b75bbb7998..32a8f9bd51 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -43,6 +43,9 @@ static char *arg_root_what = NULL;
static char *arg_root_fstype = NULL;
static char *arg_root_options = NULL;
static int arg_root_rw = -1;
+static char *arg_usr_what = NULL;
+static char *arg_usr_fstype = NULL;
+static char *arg_usr_options = NULL;
static int mount_find_pri(struct mntent *me, int *ret) {
@@ -494,12 +497,64 @@ static int add_root_mount(void) {
"/proc/cmdline");
}
+static int add_usr_mount(void) {
+ _cleanup_free_ char *what = NULL;
+ const char *opts;
+
+ if (!arg_usr_what && !arg_usr_fstype && !arg_usr_options)
+ return 0;
+
+ if (arg_root_what && !arg_usr_what) {
+ arg_usr_what = strdup(arg_root_what);
+
+ if (!arg_usr_what)
+ return log_oom();
+ }
+
+ if (arg_root_fstype && !arg_usr_fstype) {
+ arg_usr_fstype = strdup(arg_root_fstype);
+
+ if (!arg_usr_fstype)
+ return log_oom();
+ }
+
+ if (arg_root_options && !arg_usr_options) {
+ arg_usr_options = strdup(arg_root_options);
+
+ if (!arg_usr_options)
+ return log_oom();
+ }
+
+ if (!arg_usr_what || !arg_usr_options)
+ return 0;
+
+ what = fstab_node_to_udev_node(arg_usr_what);
+ if (!path_is_absolute(what)) {
+ log_debug("Skipping entry what=%s where=/sysroot/usr type=%s", what, strna(arg_usr_fstype));
+ return -1;
+ }
+
+ opts = arg_usr_options;
+
+ log_debug("Found entry what=%s where=/sysroot/usr type=%s", what, strna(arg_usr_fstype));
+ return add_mount(what,
+ "/sysroot/usr",
+ arg_usr_fstype,
+ opts,
+ 1,
+ false,
+ false,
+ false,
+ SPECIAL_INITRD_ROOT_FS_TARGET,
+ "/proc/cmdline");
+}
+
static int parse_proc_cmdline_item(const char *key, const char *value) {
int r;
- /* root= and roofstype= may occur more than once, the last
- * instance should take precedence. In the case of multiple
- * rootflags= the arguments should be concatenated */
+ /* root=, usr=, usrfstype= and roofstype= may occur more than once, the last
+ * instance should take precedence. In the case of multiple rootflags=
+ * or usrflags= the arguments should be concatenated */
if (STR_IN_SET(key, "fstab", "rd.fstab") && value) {
@@ -531,6 +586,28 @@ static int parse_proc_cmdline_item(const char *key, const char *value) {
free(arg_root_options);
arg_root_options = o;
+ } else if (streq(key, "mount.usr") && value) {
+
+ if (free_and_strdup(&arg_usr_what, value) < 0)
+ return log_oom();
+
+ } else if (streq(key, "mount.usrfstype") && value) {
+
+ if (free_and_strdup(&arg_usr_fstype, value) < 0)
+ return log_oom();
+
+ } else if (streq(key, "mount.usrflags") && value) {
+ char *o;
+
+ o = arg_usr_options ?
+ strjoin(arg_usr_options, ",", value, NULL) :
+ strdup(value);
+ if (!o)
+ return log_oom();
+
+ free(arg_usr_options);
+ arg_usr_options = o;
+
} else if (streq(key, "rw") && !value)
arg_root_rw = true;
else if (streq(key, "ro") && !value)
@@ -559,9 +636,12 @@ int main(int argc, char *argv[]) {
if (parse_proc_cmdline(parse_proc_cmdline_item) < 0)
return EXIT_FAILURE;
- /* Always honour root= in the kernel command line if we are in an initrd */
- if (in_initrd())
+ /* Always honour root= and usr= in the kernel command line if we are in an initrd */
+ if (in_initrd()) {
r = add_root_mount();
+ if (r == 0)
+ r = add_usr_mount();
+ }
/* Honour /etc/fstab only when that's enabled */
if (arg_fstab_enabled) {