From 5e398e546ea65751e6a774daf828fe06f74434a2 Mon Sep 17 00:00:00 2001 From: Tom Gundersen Date: Fri, 23 Nov 2012 03:41:13 +0100 Subject: [PATCH 1/1] fstab-generator: generate new_root.mount in initrd The configuration is taken from /proc/cmdline, aiming at emulating the behavior of the kernel when no initramfs is used. The supported options are: root=, rootfstype=, rootwait=, rootflags=, ro, and rw. rootdelay= was dropped, as it is not really useful in a systemd world, but could easily be added. v2: fix comments by Lennart, and complain loudly if root= can not be found Cc: Harald Hoyer Cc: Dave Reisner --- src/fstab-generator/fstab-generator.c | 143 +++++++++++++++++++++----- 1 file changed, 118 insertions(+), 25 deletions(-) diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c index 23e505192..6766d445c 100644 --- a/src/fstab-generator/fstab-generator.c +++ b/src/fstab-generator/fstab-generator.c @@ -210,18 +210,21 @@ static bool mount_is_network(struct mntent *me) { fstype_is_network(me->mnt_type); } -static int add_mount(const char *what, const char *where, struct mntent *me) { +static int add_mount(const char *what, const char *where, const char *type, const char *opts, + int passno, bool wait, bool noauto, bool nofail, bool automount, bool isbind, bool isnetwork, + const char *source) { char *name = NULL, *unit = NULL, *lnk = NULL, *device = NULL, *automount_name = NULL, *automount_unit = NULL; FILE *f = NULL; - bool noauto, nofail, automount, isbind, isnetwork; int r; const char *post, *pre; assert(what); assert(where); - assert(me); + assert(type); + assert(opts); + assert(source); - if (streq(me->mnt_type, "autofs")) + if (streq(type, "autofs")) return 0; if (!is_path(where)) { @@ -233,15 +236,6 @@ static int add_mount(const char *what, const char *where, struct mntent *me) { mount_point_ignore(where)) return 0; - isnetwork = mount_is_network(me); - isbind = mount_is_bind(me); - - noauto = !!hasmntopt(me, "noauto"); - nofail = !!hasmntopt(me, "nofail"); - automount = - hasmntopt(me, "comment=systemd.automount") || - hasmntopt(me, "x-systemd.automount"); - if (isnetwork) { post = SPECIAL_REMOTE_FS_TARGET; pre = SPECIAL_REMOTE_FS_PRE_TARGET; @@ -272,10 +266,12 @@ static int add_mount(const char *what, const char *where, struct mntent *me) { goto finish; } - fputs("# Automatically generated by systemd-fstab-generator\n\n" + fprintf(f, + "# Automatically generated by systemd-fstab-generator\n\n" "[Unit]\n" - "SourcePath=/etc/fstab\n" - "DefaultDependencies=no\n", f); + "SourcePath=%s\n" + "DefaultDependencies=no\n", + source); if (!path_equal(where, "/")) fprintf(f, @@ -301,14 +297,18 @@ static int add_mount(const char *what, const char *where, struct mntent *me) { "FsckPassNo=%i\n", what, where, - me->mnt_type, - me->mnt_passno); + type, + passno); - if (!isempty(me->mnt_opts) && - !streq(me->mnt_opts, "defaults")) + if (!isempty(opts) && + !streq(opts, "defaults")) fprintf(f, "Options=%s\n", - me->mnt_opts); + opts); + + if (wait) + fprintf(f, + "TimeoutSec=0\n"); fflush(f); if (ferror(f)) { @@ -466,8 +466,22 @@ static int parse_fstab(void) { if (streq(me->mnt_type, "swap")) k = add_swap(what, me); - else - k = add_mount(what, where, me); + else { + bool noauto, nofail, automount, isbind, isnetwork; + + noauto = !!hasmntopt(me, "noauto"); + nofail = !!hasmntopt(me, "nofail"); + automount = + hasmntopt(me, "comment=systemd.automount") || + hasmntopt(me, "x-systemd.automount"); + isbind = mount_is_bind(me); + isnetwork = mount_is_network(me); + + k = add_mount(what, where, me->mnt_type, me->mnt_opts, + me->mnt_passno, false, noauto, nofail, + automount, isbind, isnetwork, + "/etc/fstab"); + } free(what); free(where); @@ -481,6 +495,82 @@ finish: return r; } +static int parse_new_root_from_proc_cmdline(void) { + char *w, *state; + _cleanup_free_ char *what = NULL, *type = NULL, *opts = NULL, *line = NULL; + int r; + size_t l; + bool wait = false; + + r = read_one_line_file("/proc/cmdline", &line); + if (r < 0) { + log_error("Failed to read /proc/cmdline, ignoring: %s", strerror(-r)); + return 0; + } + + opts = strdup("defaults"); + if (!opts) + return log_oom(); + type = strdup("auto"); + if (!type) + return log_oom(); + + /* 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 */ + FOREACH_WORD_QUOTED(w, l, line, state) { + char *word, *tmp_word; + + word = strndup(w, l); + if (!word) + return log_oom(); + + else if (startswith(word, "root=")) { + free(what); + what = fstab_node_to_udev_node(word+5); + if (!what) + return log_oom(); + + } else if (startswith(word, "rootfstype=")) { + free(type); + type = strdup(word + 11); + if (!type) + return log_oom(); + + } else if (startswith(word, "rootflags=")) { + tmp_word = opts; + opts = strjoin(opts, ",", word + 10, NULL); + free(tmp_word); + if (!opts) + return log_oom(); + + } else if (streq(word, "ro") || streq(word, "rw")) { + tmp_word = opts; + opts = strjoin(opts, ",", word, NULL); + free(tmp_word); + if (!opts) + return log_oom(); + + } else if (streq(word, "rootwait")) + wait = true; + + free(word); + } + + if (what) { + + log_debug("Found entry what=%s where=/new_root type=%s", what, type); + r = add_mount(what, "/new_root", type, opts, 0, wait, false, false, + false, false, false, "/proc/cmdline"); + + if (r < 0) + return r; + } else + log_error("Could not find a root= entry on the kernel commandline."); + } + + return 0; +} + static int parse_proc_cmdline(void) { char *line, *w, *state; int r; @@ -538,7 +628,7 @@ finish: } int main(int argc, char *argv[]) { - int r; + int r, k = 0; if (argc > 1 && argc != 4) { log_error("This program takes three or no arguments."); @@ -557,10 +647,13 @@ int main(int argc, char *argv[]) { if (parse_proc_cmdline() < 0) return EXIT_FAILURE; + if (in_initrd()) + k = parse_new_root_from_proc_cmdline(); + if (!arg_enabled) return EXIT_SUCCESS; r = parse_fstab(); - return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; + return (r < 0) || (k < 0) ? EXIT_FAILURE : EXIT_SUCCESS; } -- 2.30.2