diff options
| -rw-r--r-- | doc/s6-linux-init-maker.html | 33 | ||||
| -rw-r--r-- | doc/s6-linux-init.html | 19 | ||||
| -rw-r--r-- | src/init/s6-linux-init-maker.c | 20 | ||||
| -rw-r--r-- | src/init/s6-linux-init.c | 31 |
4 files changed, 82 insertions, 21 deletions
diff --git a/doc/s6-linux-init-maker.html b/doc/s6-linux-init-maker.html index 6c52d32..02fd15d 100644 --- a/doc/s6-linux-init-maker.html +++ b/doc/s6-linux-init-maker.html @@ -59,6 +59,7 @@ machine</em>. If it is not the case, the system will fail to boot. [ -e <em>initial_envvar</em> ] ... \ [ -q <em>finalsleeptime</em> ] \ [ -D <em>initdefault</em> ] \ + [ -n | -N ] [ -U <em>utmp_user</em> ] \ <em>dir</em> </pre> @@ -169,7 +170,7 @@ is defined. </li> <p /> <li> <tt>-1</tt> : make it so that all the messages that are sent to the catch-all logger (i.e. all the error messages that are not caught by a dedicated logger, as well as the output from <em>rc.init</em>, -<em>runlevel</em> and <em>rc.shutdown</em>, +<em>runlevel</em> and <em>rc.shutdown</em>) are also copied to <tt>/dev/console</tt>. (Timestamps are not copied to <tt>/dev/console</tt>.) This is generally useful to debug a system at a glance, but if a failing program keeps sending @@ -264,6 +265,36 @@ sysvinit behaviour) or <tt>default</tt> (OpenRC behaviour). Default is command line, it will be interpreted as the runlevel to boot the system on, and will override the default given here. </li> <p /> + <li> <tt>-n</tt> : at boot time, assume that a tmpfs is already +present on <tt>/run</tt> (or the argument that was given to the +<tt>--tmpfsdir</tt> configure option at build time) and that its +contents are essential. Instead of unmounting <tt>/run</tt> then +mounting a tmpfs on it, <a href="s6-linux-init.html">s6-linux-init</a> +will simply remount <tt>/run</tt>. This option is useful when +s6-linux-init is used on a distribution that imposes its initramfs +and said initramfs writes data to <tt>/run</tt> that is then used +by the distribution's initialization scripts. (An initramfs should +normally be transparent and leave no trace in the filesystem; +unfortunately, a lot of distributions do not care.) By default, +<tt>/run</tt> will be unmounted at boot time (just in case), and +then a tmpfs will be mounted on it. <strong>Do not</strong> use +this option if you are not sure: failure to remount <tt>/run</tt> +will cause init to die and the kernel to panic. This option is +incompatible with the <tt>-N</tt> option. </li> <p /> + + <li> <tt>-N</tt> : at boot time, do not perform +mounting/unmounting/remounting on <tt>/run</tt> (or the <em>tmpfsdir</em> +declared at build time) <strong>at all</strong>. By default, +a tmpfs is mounted on <tt>/run</tt> at boot time. This option is +useful when s6-linux-init is used to boot on an initramfs that +will remain the de facto rootfs of the system (which is the case +for instance in certain live CDs or certain embedded devices), in +which case the rootfs is already read-write and in RAM and mounting +an additional tmpfs is unnecessary. <strong>Do not</strong> use this +option if your rootfs is read-only: failure to write to <tt>/run</tt> +will cause init to die and the kernel to panic. This option is +incompatible with the <tt>-n</tt> option. </li> <p /> + <li> <tt>-U</tt> <em>utmp_user</em> : this option is only available when the s6-linux-init package has been built with the <tt>--enable-utmps</tt> configure option, that enables support for the diff --git a/doc/s6-linux-init.html b/doc/s6-linux-init.html index 31014d6..f57adae 100644 --- a/doc/s6-linux-init.html +++ b/doc/s6-linux-init.html @@ -27,7 +27,7 @@ and execs into <a href="//skarnet.org/software/s6/s6-svscan.html">s6-svscan</a>. <h2> Interface </h2> <pre> - s6-linux-init [ -c <em>basedir</em> ] [ -p <em>initial_path</em> ] [ -s <em>env_store</em> ] [ -m <em>umask</em> ] [ -d <em>dev_style</em> ] [ -D <em>initdefault</em> ] [ <em>args...</em> ] + s6-linux-init [ -c <em>basedir</em> ] [ -p <em>initial_path</em> ] [ -s <em>env_store</em> ] [ -m <em>umask</em> ] [ -d <em>dev_style</em> ] [ -D <em>initdefault</em> ] [ -n | -N ] [ <em>args...</em> ] </pre> <ul> @@ -57,14 +57,16 @@ the PATH environment variable. </li> <li> <tt>-s</tt> <em>env_store</em> : the place where to dump kernel environment variables. </li> <li> <tt>-m</tt> <em>initial_umask</em> : the initial file umask. </li> - <li> <tt>-d</tt> <em>dev_style</em> : how <tt>/dev</tt> is -handled on this system. 0 means a static <tt>/dev</tt>, 1 means -devtmpfs but not automounted by the kernel at boot time, and 2 means -devtmpfs automounted by the kernel at boot time. </li> + <li> <tt>-d</tt> <em>slashdev</em> : mount a devtmpfs on +<em>slashdev</em>. By default, no such mount is performed - it is assumed +that a devtmpfs is automounted on <tt>/dev</tt> at boot time by the kernel. </li> <li> <tt>-D</tt> <em>initdefault</em> : the initial runlevel to boot to, if it isn't overridden by the kernel command line. This is only given as a first argument to <em>rc.init</em>. Default is <tt>default</tt>. </li> + <li> <tt>-n</tt> : instead of unmounting <tt>/run</tt> and mounting +a tmpfs on it, just remount <tt>/run</tt>. </li> + <li> <tt>-N</tt> : do not touch <tt>/run</tt> at all. </li> </ul> <h2> Early preparation </h2> @@ -79,12 +81,13 @@ operations: <li> It chdirs to <tt>/</tt>. </li> <li> It sets the umask to <em>initial_umask</em>. </li> <li> It becomes a session leader. </li> - <li> It mounts a devtmpfs on <tt>/dev</tt>, if necessary. </li> + <li> It mounts a devtmpfs on <em>slashdev</em>, if requested. </li> <li> It uses <tt>/dev/null</tt> as its stdin (instead of <tt>/dev/console</tt>). <tt>/dev/console</tt> is still used, for now, as stdout and stderr. </li> <li> It unmounts <tt>/run</tt> (or the directory you have given to the -<tt>--tmpfsdir</tt> configure option at package build time), just in case. </li> - <li> It creates a tmpfs on <tt>/run</tt> (or your chosen <em>tmpfsdir</em>). </li> +<tt>--tmpfsdir</tt> configure option at package build time), just in case; +then it creates a tmpfs on it. Alternatively, it remounts <tt>/run</tt>, +or does not touch it at all. </li> <li> It copies the whole <tt><em>basedir</em>/run-image</tt> hierarchy to <tt>/run</tt> (or your chosen tmpfsdir). </li> <li> It reads the initial environment from <tt><em>basedir</em>/env</tt>. </li> diff --git a/src/init/s6-linux-init-maker.c b/src/init/s6-linux-init-maker.c index 434e29f..1005811 100644 --- a/src/init/s6-linux-init-maker.c +++ b/src/init/s6-linux-init-maker.c @@ -28,12 +28,12 @@ #ifdef S6_LINUX_INIT_UTMPD_PATH # include <utmps/config.h> -# define USAGE "s6-linux-init-maker [ -c basedir ] [ -u log_user ] [ -G early_getty_cmd ] [ -1 ] [ -L ] [ -p initial_path ] [ -m initial_umask ] [ -t timestamp_style ] [ -d slashdev ] [ -s env_store ] [ -e initial_envvar ... ] [ -q default_grace_time ] [ -D initdefault ] [ -U utmp_user ] dir" -# define OPTION_STRING "c:u:G:1Lp:m:t:d:s:e:E:q:U:D:" +# define USAGE "s6-linux-init-maker [ -c basedir ] [ -u log_user ] [ -G early_getty_cmd ] [ -1 ] [ -L ] [ -p initial_path ] [ -m initial_umask ] [ -t timestamp_style ] [ -d slashdev ] [ -s env_store ] [ -e initial_envvar ... ] [ -q default_grace_time ] [ -D initdefault ] [ -n | -N ] [ -U utmp_user ] dir" +# define OPTION_STRING "c:u:G:1Lp:m:t:d:s:e:E:q:D:nNU:" # define UTMPS_DIR "utmps" #else -# define USAGE "s6-linux-init-maker [ -c basedir ] [ -u log_user ] [ -G early_getty_cmd ] [ -1 ] [ -L ] [ -p initial_path ] [ -m initial_umask ] [ -t timestamp_style ] [ -d slashdev ] [ -s env_store ] [ -e initial_envvar ... ] [ -q default_grace_time ] [ -D initdefault ] dir" -# define OPTION_STRING "c:u:G:1Lp:m:t:d:s:e:E:q:D:" +# define USAGE "s6-linux-init-maker [ -c basedir ] [ -u log_user ] [ -G early_getty_cmd ] [ -1 ] [ -L ] [ -p initial_path ] [ -m initial_umask ] [ -t timestamp_style ] [ -d slashdev ] [ -s env_store ] [ -e initial_envvar ... ] [ -q default_grace_time ] [ -D initdefault ] [ -n | -N ] dir" +# define OPTION_STRING "c:u:G:1Lp:m:t:d:s:e:E:q:D:nN" #endif #define dieusage() strerr_dieusage(100, USAGE) @@ -51,6 +51,7 @@ static char const *initdefault = 0 ; static unsigned int initial_umask = 0022 ; static unsigned int timestamp_style = 1 ; static unsigned int finalsleep = 3000 ; +static int mounttype = 1 ; static int console = 0 ; static int logouthookd = 0 ; @@ -233,6 +234,15 @@ static inline int stage1_script (buffer *b, char const *data) if (buffer_put(b, satmp.s + sabase, satmp.len - sabase) < 0) goto err ; satmp.len = sabase ; } + if (mounttype == 2) + { + if (buffer_puts(b, " -n") < 0) return 0 ; + } + else if (!mounttype) + { + if (buffer_puts(b, " -N") < 0) return 0 ; + } + if (buffer_puts(b, "\n") < 0) return 0 ; (void)data ; return 1 ; @@ -575,6 +585,8 @@ int main (int argc, char const *const *argv, char const *const *envp) case 'e' : if (!stralloc_catb(&satmp, l.arg, strlen(l.arg) + 1)) dienomem() ; break ; case 'q' : if (!uint0_scan(l.arg, &finalsleep)) dieusage() ; break ; case 'D' : initdefault = l.arg ; break ; + case 'n' : mounttype = 2 ; break ; + case 'N' : mounttype = 0 ; break ; #ifdef S6_LINUX_INIT_UTMPD_PATH case 'U' : utmp_user = l.arg ; break ; #endif diff --git a/src/init/s6-linux-init.c b/src/init/s6-linux-init.c index b6113a9..e322fa4 100644 --- a/src/init/s6-linux-init.c +++ b/src/init/s6-linux-init.c @@ -23,7 +23,7 @@ #include "defaults.h" #include "initctl.h" -#define USAGE "s6-linux-init [ -c basedir ] [ -p initpath ] [ -s envdumpdir ] [ -m umask ] [ -d devtmpfs ] [ -D initdefault ]" +#define USAGE "s6-linux-init [ -c basedir ] [ -p initpath ] [ -s envdumpdir ] [ -m umask ] [ -d devtmpfs ] [ -D initdefault ] [ -n | -N ]" #define dieusage() strerr_dieusage(100, USAGE) #define BANNER "\n s6-linux-init version " S6_LINUX_INIT_VERSION "\n\n" @@ -68,6 +68,7 @@ int main (int argc, char const **argv, char const *const *envp) char const *slashdev = 0 ; char const *envdumpdir = 0 ; char const *initdefault = "default" ; + int mounttype = 1 ; stralloc envmodifs = STRALLOC_ZERO ; PROG = "s6-linux-init" ; @@ -82,7 +83,7 @@ int main (int argc, char const **argv, char const *const *envp) subgetopt_t l = SUBGETOPT_ZERO ; for (;;) { - int opt = subgetopt_r(argc, argv, "c:p:s:m:d:D:", &l) ; + int opt = subgetopt_r(argc, argv, "c:p:s:m:d:D:nN", &l) ; if (opt == -1) break ; switch (opt) { @@ -92,6 +93,8 @@ int main (int argc, char const **argv, char const *const *envp) case 'm' : if (!uint0_oscan(l.arg, &mask)) dieusage() ; break ; case 'd' : slashdev = l.arg ; break ; case 'D' : initdefault = l.arg ; break ; + case 'n' : mounttype = 2 ; break ; + case 'N' : mounttype = 0 ; break ; default : dieusage() ; } } @@ -121,14 +124,26 @@ int main (int argc, char const **argv, char const *const *envp) || fd_move(2, 0) == -1) return 111 ; } if (open("/dev/null", O_RDONLY)) strerr_diefu1sys(111, "open /dev/null") ; - - if (umount(S6_LINUX_INIT_TMPFS) == -1) + + if (mounttype) { - if (errno != EINVAL) - strerr_warnwu1sys("umount " S6_LINUX_INIT_TMPFS) ; + if (mounttype == 2) + { + if (mount("tmpfs", S6_LINUX_INIT_TMPFS, "tmpfs", MS_REMOUNT | MS_NODEV | MS_NOSUID, "mode=0755") == -1) + strerr_diefu1sys(111, "remount " S6_LINUX_INIT_TMPFS) ; + } + else + { + if (umount(S6_LINUX_INIT_TMPFS) == -1) + { + if (errno != EINVAL) + strerr_warnwu1sys("umount " S6_LINUX_INIT_TMPFS) ; + } + if (mount("tmpfs", S6_LINUX_INIT_TMPFS, "tmpfs", MS_NODEV | MS_NOSUID, "mode=0755") == -1) + strerr_diefu1sys(111, "mount tmpfs on " S6_LINUX_INIT_TMPFS) ; + } } - if (mount("tmpfs", S6_LINUX_INIT_TMPFS, "tmpfs", MS_NODEV | MS_NOSUID, "mode=0755") == -1) - strerr_diefu1sys(111, "mount tmpfs on " S6_LINUX_INIT_TMPFS) ; + { size_t dirlen = strlen(basedir) ; char fn[dirlen + 1 + (sizeof(RUNIMAGE) > sizeof(ENVSTAGE1) ? sizeof(RUNIMAGE) : sizeof(ENVSTAGE1))] ; |