chiark / gitweb /
fstab-generator: use more appropriate checks for swap and device availability
[elogind.git] / src / fstab-generator / fstab-generator.c
index d4470f4fb8b3f8b2f4afa6b25114d734d86b5fe4..496657bdc176a25b170788d8304bf306ceff5b1b 100644 (file)
 #include "mount-setup.h"
 #include "special.h"
 #include "mkdir.h"
-#include "virt.h"
 #include "fileio.h"
+#include "generator.h"
+#include "strv.h"
+#include "virt.h"
 
 static const char *arg_dest = "/tmp";
-static bool arg_enabled = true;
-
-static int device_name(const char *path, char **unit) {
-        char *p;
-
-        assert(path);
-
-        if (!is_device_path(path))
-                return 0;
-
-        p = unit_name_from_path(path, ".device");
-        if (!p)
-                return log_oom();
-
-        *unit = p;
-        return 1;
-}
+static bool arg_fstab_enabled = true;
+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) {
-        char *end, *pri;
+        char *end, *opt;
         unsigned long r;
 
         assert(me);
         assert(ret);
 
-        pri = hasmntopt(me, "pri");
-        if (!pri)
+        opt = hasmntopt(me, "pri");
+        if (!opt)
                 return 0;
 
-        pri += 4;
+        opt += strlen("pri");
+        if (*opt != '=')
+                return -EINVAL;
 
         errno = 0;
-        r = strtoul(pri, &end, 10);
-        if (errno != 0)
+        r = strtoul(opt + 1, &end, 10);
+        if (errno > 0)
                 return -errno;
 
-        if (end == pri || (*end != ',' && *end != 0))
+        if (end == opt + 1 || (*end != ',' && *end != 0))
                 return -EINVAL;
 
         *ret = (int) r;
         return 1;
 }
 
-static int add_swap(const char *what, struct mntent *me) {
-        char _cleanup_free_ *name = NULL, *unit = NULL, *lnk = NULL, *device = NULL;
-        FILE _cleanup_fclose_ *f = NULL;
-        bool noauto, nofail;
+static int add_swap(
+                const char *what,
+                struct mntent *me,
+                bool noauto,
+                bool nofail) {
+
+        _cleanup_free_ char *name = NULL, *unit = NULL, *lnk = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
         int r, pri = -1;
 
         assert(what);
         assert(me);
 
+        if (access("/proc/swaps", F_OK) < 0) {
+                log_info("Swap not supported, ignoring fstab swap entry for %s.", what);
+                return 0;
+        }
+
+        if (detect_container(NULL) > 0) {
+                log_info("Running in a container, ignoring fstab swap entry for %s.", what);
+                return 0;
+        }
+
         r = mount_find_pri(me, &pri);
         if (r < 0) {
                 log_error("Failed to parse priority");
-                return pri;
+                return r;
         }
 
-        noauto = !!hasmntopt(me, "noauto");
-        nofail = !!hasmntopt(me, "nofail");
-
         name = unit_name_from_path(what, ".swap");
         if (!name)
                 return log_oom();
@@ -110,104 +116,91 @@ static int add_swap(const char *what, struct mntent *me) {
                 if (errno == EEXIST)
                         log_error("Failed to create swap unit file %s, as it already exists. Duplicate entry in /etc/fstab?", unit);
                 else
-                        log_error("Failed to create unit file %s: %m", unit);
+                        log_error_errno(errno, "Failed to create unit file %s: %m", unit);
                 return -errno;
         }
 
-        fputs("# Automatically generated by systemd-fstab-generator\n\n"
-              "[Unit]\n"
-              "SourcePath=/etc/fstab\n"
-              "DefaultDependencies=no\n"
-              "Conflicts=" SPECIAL_UMOUNT_TARGET "\n"
-              "Before=" SPECIAL_UMOUNT_TARGET "\n", f);
-
-        if (!noauto && !nofail)
-                fputs("Before=" SPECIAL_SWAP_TARGET "\n", f);
-
         fprintf(f,
-                "\n"
+                "# Automatically generated by systemd-fstab-generator\n\n"
+                "[Unit]\n"
+                "SourcePath=/etc/fstab\n"
+                "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n\n"
                 "[Swap]\n"
                 "What=%s\n",
                 what);
 
+        /* Note that we currently pass the priority field twice, once
+         * in Priority=, and once in Options= */
         if (pri >= 0)
-                fprintf(f,
-                        "Priority=%i\n",
-                        pri);
+                fprintf(f, "Priority=%i\n", pri);
 
-        fflush(f);
-        if (ferror(f)) {
-                log_error("Failed to write unit file %s: %m", unit);
-                return -errno;
-        }
+        if (!isempty(me->mnt_opts) && !streq(me->mnt_opts, "defaults"))
+                fprintf(f, "Options=%s\n", me->mnt_opts);
+
+        r = fflush_and_check(f);
+        if (r < 0)
+                return log_error_errno(r, "Failed to write unit file %s: %m", unit);
+
+        /* use what as where, to have a nicer error message */
+        r = generator_write_timeouts(arg_dest, what, what, me->mnt_opts, NULL);
+        if (r < 0)
+                return r;
 
         if (!noauto) {
-                lnk = strjoin(arg_dest, "/" SPECIAL_SWAP_TARGET ".wants/", name, NULL);
+                lnk = strjoin(arg_dest, "/" SPECIAL_SWAP_TARGET,
+                              nofail ? ".wants/" : ".requires/", name, NULL);
                 if (!lnk)
                         return log_oom();
 
                 mkdir_parents_label(lnk, 0755);
-                if (symlink(unit, lnk) < 0) {
-                        log_error("Failed to create symlink %s: %m", lnk);
-                        return -errno;
-                }
-
-                r = device_name(what, &device);
-                if (r < 0)
-                        return r;
-
-                if (r > 0) {
-                        free(lnk);
-                        lnk = strjoin(arg_dest, "/", device, ".wants/", name, NULL);
-                        if (!lnk)
-                                return log_oom();
-
-                        mkdir_parents_label(lnk, 0755);
-                        if (symlink(unit, lnk) < 0) {
-                                log_error("Failed to create symlink %s: %m", lnk);
-                                return -errno;
-                        }
-                }
+                if (symlink(unit, lnk) < 0)
+                        return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
         }
 
         return 0;
 }
 
-static bool mount_is_bind(struct mntent *me) {
+static bool mount_is_network(struct mntent *me) {
         assert(me);
 
         return
-                hasmntopt(me, "bind") ||
-                streq(me->mnt_type, "bind") ||
-                hasmntopt(me, "rbind") ||
-                streq(me->mnt_type, "rbind");
+                hasmntopt(me, "_netdev") ||
+                fstype_is_network(me->mnt_type);
 }
 
-static bool mount_is_network(struct mntent *me) {
+static bool mount_in_initrd(struct mntent *me) {
         assert(me);
 
         return
-                hasmntopt(me, "_netdev") ||
-                fstype_is_network(me->mnt_type);
+                hasmntopt(me, "x-initrd.mount") ||
+                streq(me->mnt_dir, "/usr");
 }
 
-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 _cleanup_free_
-                *name = NULL, *unit = NULL, *lnk = NULL, *device = NULL,
-                *automount_name = NULL, *automount_unit = NULL;
-        FILE _cleanup_fclose_ *f = NULL;
+static int add_mount(
+                const char *what,
+                const char *where,
+                const char *fstype,
+                const char *opts,
+                int passno,
+                bool noauto,
+                bool nofail,
+                bool automount,
+                const char *post,
+                const char *source) {
+
+        _cleanup_free_ char
+                *name = NULL, *unit = NULL, *lnk = NULL,
+                *automount_name = NULL, *automount_unit = NULL,
+                *filtered = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
         int r;
-        const char *post, *pre;
 
         assert(what);
         assert(where);
-        assert(type);
         assert(opts);
         assert(source);
 
-        if (streq(type, "autofs"))
+        if (streq_ptr(fstype, "autofs"))
                 return 0;
 
         if (!is_path(where)) {
@@ -219,12 +212,11 @@ static int add_mount(const char *what, const char *where, const char *type, cons
             mount_point_ignore(where))
                 return 0;
 
-        if (isnetwork) {
-                post = SPECIAL_REMOTE_FS_TARGET;
-                pre = SPECIAL_REMOTE_FS_PRE_TARGET;
-        } else {
-                post = SPECIAL_LOCAL_FS_TARGET;
-                pre = SPECIAL_LOCAL_FS_PRE_TARGET;
+        if (path_equal(where, "/")) {
+                /* The root disk is not an option */
+                automount = false;
+                noauto = false;
+                nofail = false;
         }
 
         name = unit_name_from_path(where, ".mount");
@@ -240,96 +232,61 @@ static int add_mount(const char *what, const char *where, const char *type, cons
                 if (errno == EEXIST)
                         log_error("Failed to create mount unit file %s, as it already exists. Duplicate entry in /etc/fstab?", unit);
                 else
-                        log_error("Failed to create unit file %s: %m", unit);
+                        log_error_errno(errno, "Failed to create unit file %s: %m", unit);
                 return -errno;
         }
 
         fprintf(f,
-              "# Automatically generated by systemd-fstab-generator\n\n"
-              "[Unit]\n"
-              "SourcePath=%s\n"
-              "DefaultDependencies=no\n",
-              source);
-
-        if (!path_equal(where, "/"))
-                fprintf(f,
-                        "After=%s\n"
-                        "Wants=%s\n"
-                        "Conflicts=" SPECIAL_UMOUNT_TARGET "\n"
-                        "Before=" SPECIAL_UMOUNT_TARGET "\n",
-                        pre,
-                        pre);
+                "# Automatically generated by systemd-fstab-generator\n\n"
+                "[Unit]\n"
+                "SourcePath=%s\n"
+                "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n",
+                source);
 
+        if (post && !noauto && !nofail && !automount)
+                fprintf(f, "Before=%s\n", post);
 
-        if (!noauto && !nofail && !automount)
-                fprintf(f,
-                        "Before=%s\n",
-                        post);
+        if (passno != 0) {
+                r = generator_write_fsck_deps(f, arg_dest, what, where, fstype);
+                if (r < 0)
+                        return r;
+        }
 
         fprintf(f,
                 "\n"
                 "[Mount]\n"
                 "What=%s\n"
-                "Where=%s\n"
-                "Type=%s\n"
-                "FsckPassNo=%i\n",
+                "Where=%s\n",
                 what,
-                where,
-                type,
-                passno);
+                where);
 
-        if (!isempty(opts) &&
-            !streq(opts, "defaults"))
-                fprintf(f,
-                        "Options=%s\n",
-                        opts);
+        if (!isempty(fstype) && !streq(fstype, "auto"))
+                fprintf(f, "Type=%s\n", fstype);
 
-        if (wait)
-                fprintf(f,
-                        "TimeoutSec=0\n");
+        r = generator_write_timeouts(arg_dest, what, where, opts, &filtered);
+        if (r < 0)
+                return r;
+
+        if (!isempty(filtered) && !streq(filtered, "defaults"))
+                fprintf(f, "Options=%s\n", filtered);
 
         fflush(f);
-        if (ferror(f)) {
-                log_error("Failed to write unit file %s: %m", unit);
-                return -errno;
-        }
+        if (ferror(f))
+                return log_error_errno(errno, "Failed to write unit file %s: %m", unit);
 
-        if (!noauto) {
+        if (!noauto && post) {
                 lnk = strjoin(arg_dest, "/", post, nofail || automount ? ".wants/" : ".requires/", name, NULL);
                 if (!lnk)
                         return log_oom();
 
                 mkdir_parents_label(lnk, 0755);
-                if (symlink(unit, lnk) < 0) {
-                        log_error("Failed to create symlink %s: %m", lnk);
-                        return -errno;
-                }
-
-                if (!isbind &&
-                    !path_equal(where, "/")) {
-
-                        r = device_name(what, &device);
-                        if (r < 0)
-                                return r;
-
-                        if (r > 0) {
-                                free(lnk);
-                                lnk = strjoin(arg_dest, "/", device, ".wants/", name, NULL);
-                                if (!lnk)
-                                        return log_oom();
-
-                                mkdir_parents_label(lnk, 0755);
-                                if (symlink(unit, lnk) < 0) {
-                                        log_error("Failed to create symlink %s: %m", lnk);
-                                        return -errno;
-                                }
-                        }
-                }
+                if (symlink(unit, lnk) < 0)
+                        return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
         }
 
-        if (automount && !path_equal(where, "/")) {
+        if (automount) {
                 automount_name = unit_name_from_path(where, ".automount");
-                if (!name)
+                if (!automount_name)
                         return log_oom();
 
                 automount_unit = strjoin(arg_dest, "/", automount_name, NULL);
@@ -338,29 +295,29 @@ static int add_mount(const char *what, const char *where, const char *type, cons
 
                 fclose(f);
                 f = fopen(automount_unit, "wxe");
-                if (!f) {
-                        log_error("Failed to create unit file %s: %m", automount_unit);
-                        return -errno;
-                }
+                if (!f)
+                        return log_error_errno(errno, "Failed to create unit file %s: %m", automount_unit);
 
                 fprintf(f,
                         "# Automatically generated by systemd-fstab-generator\n\n"
                         "[Unit]\n"
-                        "SourcePath=/etc/fstab\n"
-                        "DefaultDependencies=no\n"
-                        "Conflicts=" SPECIAL_UMOUNT_TARGET "\n"
-                        "Before=" SPECIAL_UMOUNT_TARGET " %s\n"
-                        "\n"
+                        "SourcePath=%s\n"
+                        "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n",
+                        source);
+
+                if (post)
+                        fprintf(f,
+                                "Before=%s\n",
+                                post);
+
+                fprintf(f,
                         "[Automount]\n"
                         "Where=%s\n",
-                        post,
                         where);
 
                 fflush(f);
-                if (ferror(f)) {
-                        log_error("Failed to write unit file %s: %m", automount_unit);
-                        return -errno;
-                }
+                if (ferror(f))
+                        return log_error_errno(errno, "Failed to write unit file %s: %m", automount_unit);
 
                 free(lnk);
                 lnk = strjoin(arg_dest, "/", post, nofail ? ".wants/" : ".requires/", automount_name, NULL);
@@ -368,197 +325,261 @@ static int add_mount(const char *what, const char *where, const char *type, cons
                         return log_oom();
 
                 mkdir_parents_label(lnk, 0755);
-                if (symlink(automount_unit, lnk) < 0) {
-                        log_error("Failed to create symlink %s: %m", lnk);
-                        return -errno;
-                }
+                if (symlink(automount_unit, lnk) < 0)
+                        return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
         }
 
         return 0;
 }
 
-static int parse_fstab(void) {
-        FILE *f;
-        int r = 0;
+static int parse_fstab(bool initrd) {
+        _cleanup_endmntent_ FILE *f = NULL;
+        const char *fstab_path;
         struct mntent *me;
+        int r = 0;
 
-        errno = 0;
-        f = setmntent("/etc/fstab", "r");
+        fstab_path = initrd ? "/sysroot/etc/fstab" : "/etc/fstab";
+        f = setmntent(fstab_path, "re");
         if (!f) {
                 if (errno == ENOENT)
                         return 0;
 
-                log_error("Failed to open /etc/fstab: %m");
+                log_error_errno(errno, "Failed to open %s: %m", fstab_path);
                 return -errno;
         }
 
         while ((me = getmntent(f))) {
-                char _cleanup_free_ *where = NULL, *what = NULL;
+                _cleanup_free_ char *where = NULL, *what = NULL;
+                bool noauto, nofail;
                 int k;
 
+                if (initrd && !mount_in_initrd(me))
+                        continue;
+
                 what = fstab_node_to_udev_node(me->mnt_fsname);
-                where = strdup(me->mnt_dir);
-                if (!what || !where) {
-                        r = log_oom();
-                        goto finish;
+                if (!what)
+                        return log_oom();
+
+                if (is_device_path(what) && path_is_read_only_fs("sys") > 0) {
+                        log_info("Running in a container, ignoring fstab device entry for %s.", what);
+                        continue;
                 }
 
+                where = initrd ? strappend("/sysroot/", me->mnt_dir) : strdup(me->mnt_dir);
+                if (!where)
+                        return log_oom();
+
                 if (is_path(where))
                         path_kill_slashes(where);
 
-                log_debug("Found entry what=%s where=%s type=%s", what, where, me->mnt_type);
+                noauto = !!hasmntopt(me, "noauto");
+                nofail = !!hasmntopt(me, "nofail");
+                log_debug("Found entry what=%s where=%s type=%s nofail=%s noauto=%s",
+                          what, where, me->mnt_type,
+                          yes_no(noauto), yes_no(nofail));
 
                 if (streq(me->mnt_type, "swap"))
-                        k = add_swap(what, me);
+                        k = add_swap(what, me, noauto, nofail);
                 else {
-                        bool noauto, nofail, automount, isbind, isnetwork;
+                        bool automount;
+                        const char *post;
 
-                        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");
+                        if (initrd)
+                                post = SPECIAL_INITRD_FS_TARGET;
+                        else if (mount_in_initrd(me))
+                                post = SPECIAL_INITRD_ROOT_FS_TARGET;
+                        else if (mount_is_network(me))
+                                post = SPECIAL_REMOTE_FS_TARGET;
+                        else
+                                post = SPECIAL_LOCAL_FS_TARGET;
+
+                        k = add_mount(what,
+                                      where,
+                                      me->mnt_type,
+                                      me->mnt_opts,
+                                      me->mnt_passno,
+                                      noauto,
+                                      nofail,
+                                      automount,
+                                      post,
+                                      fstab_path);
                 }
 
                 if (k < 0)
                         r = k;
         }
 
-finish:
-        endmntent(f);
         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;
+static int add_root_mount(void) {
+        _cleanup_free_ char *what = NULL;
+        const char *opts;
 
-        r = read_one_line_file("/proc/cmdline", &line);
-        if (r < 0) {
-                log_error("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
+        if (isempty(arg_root_what)) {
+                log_debug("Could not find a root= entry on the kernel command line.");
                 return 0;
         }
 
-        type = strdup("auto");
-        if (!opts || !type)
-                return log_oom();
+        what = fstab_node_to_udev_node(arg_root_what);
+        if (!path_is_absolute(what)) {
+                log_debug("Skipping entry what=%s where=/sysroot type=%s", what, strna(arg_root_fstype));
+                return 0;
+        }
+
+        if (!arg_root_options)
+                opts = arg_root_rw > 0 ? "rw" : "ro";
+        else if (arg_root_rw >= 0 ||
+                 (!mount_test_option(arg_root_options, "ro") &&
+                  !mount_test_option(arg_root_options, "rw")))
+                opts = strappenda(arg_root_options, ",", arg_root_rw > 0 ? "rw" : "ro");
+        else
+                opts = arg_root_options;
+
+        log_debug("Found entry what=%s where=/sysroot type=%s", what, strna(arg_root_fstype));
+        return add_mount(what,
+                         "/sysroot",
+                         arg_root_fstype,
+                         opts,
+                         1,
+                         false,
+                         false,
+                         false,
+                         SPECIAL_INITRD_ROOT_FS_TARGET,
+                         "/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;
 
-        /* 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;
+        if (arg_root_what && !arg_usr_what) {
+                arg_usr_what = strdup(arg_root_what);
 
-                word = strndup(w, l);
-                if (!word)
+                if (!arg_usr_what)
                         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 (arg_root_fstype && !arg_usr_fstype) {
+                arg_usr_fstype = strdup(arg_root_fstype);
+
+                if (!arg_usr_fstype)
+                        return log_oom();
         }
 
-        if (what) {
+        if (arg_root_options && !arg_usr_options) {
+                arg_usr_options = strdup(arg_root_options);
 
-                log_debug("Found entry what=%s where=/sysroot type=%s", what, type);
-                r = add_mount(what, "/sysroot", type, opts, 0, wait, false, false,
-                              false, false, false, "/proc/cmdline");
+                if (!arg_usr_options)
+                        return log_oom();
+        }
 
-                if (r < 0)
-                        return r;
-        } else
-                log_error("Could not find a root= entry on the kernel commandline.");
+        if (!arg_usr_what)
+                return 0;
 
-        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;
+        }
+
+        if (!arg_usr_options)
+                opts = arg_root_rw > 0 ? "rw" : "ro";
+        else if (!mount_test_option(arg_usr_options, "ro") &&
+                 !mount_test_option(arg_usr_options, "rw"))
+                opts = strappenda(arg_usr_options, ",", arg_root_rw > 0 ? "rw" : "ro");
+        else
+                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(void) {
-        char _cleanup_free_ *line = NULL;
-        char *w, *state;
+static int parse_proc_cmdline_item(const char *key, const char *value) {
         int r;
-        size_t l;
 
-        if (detect_container(NULL) > 0)
-                return 0;
+        /* 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 */
 
-        r = read_one_line_file("/proc/cmdline", &line);
-        if (r < 0) {
-                log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
-                return 0;
-        }
+        if (STR_IN_SET(key, "fstab", "rd.fstab") && value) {
 
-        FOREACH_WORD_QUOTED(w, l, line, state) {
-                char _cleanup_free_ *word = NULL;
+                r = parse_boolean(value);
+                if (r < 0)
+                        log_warning("Failed to parse fstab switch %s. Ignoring.", value);
+                else
+                        arg_fstab_enabled = r;
 
-                word = strndup(w, l);
-                if (!word)
+        } else if (streq(key, "root") && value) {
+
+                if (free_and_strdup(&arg_root_what, value) < 0)
                         return log_oom();
 
-                if (startswith(word, "fstab=")) {
-                        r = parse_boolean(word + 6);
-                        if (r < 0)
-                                log_warning("Failed to parse fstab switch %s. Ignoring.", word + 6);
-                        else
-                                arg_enabled = r;
+        } else if (streq(key, "rootfstype") && value) {
 
-                } else if (startswith(word, "rd.fstab=")) {
+                if (free_and_strdup(&arg_root_fstype, value) < 0)
+                        return log_oom();
 
-                        if (in_initrd()) {
-                                r = parse_boolean(word + 6);
-                                if (r < 0)
-                                        log_warning("Failed to parse fstab switch %s. Ignoring.", word + 6);
-                                else
-                                        arg_enabled = r;
-                        }
+        } else if (streq(key, "rootflags") && value) {
+                char *o;
 
-                } else if (startswith(word, "fstab.") ||
-                           (in_initrd() && startswith(word, "rd.fstab."))) {
+                o = arg_root_options ?
+                        strjoin(arg_root_options, ",", value, NULL) :
+                        strdup(value);
+                if (!o)
+                        return log_oom();
 
-                        log_warning("Unknown kernel switch %s. Ignoring.", word);
-                }
-        }
+                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)
+                arg_root_rw = false;
 
         return 0;
 }
 
 int main(int argc, char *argv[]) {
-        int r, k = 0;
+        int r = 0;
 
         if (argc > 1 && argc != 4) {
                 log_error("This program takes three or no arguments.");
@@ -574,16 +595,45 @@ int main(int argc, char *argv[]) {
 
         umask(0022);
 
-        if (parse_proc_cmdline() < 0)
-                return EXIT_FAILURE;
+        r = parse_proc_cmdline(parse_proc_cmdline_item);
+        if (r < 0)
+                log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
+
+        /* 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) {
+                int k;
+
+                log_debug("Parsing /etc/fstab");
+
+                /* Parse the local /etc/fstab, possibly from the initrd */
+                k = parse_fstab(false);
+                if (k < 0)
+                        r = k;
+
+                /* If running in the initrd also parse the /etc/fstab from the host */
+                if (in_initrd()) {
+                        log_debug("Parsing /sysroot/etc/fstab");
 
-        if (in_initrd())
-                k = parse_new_root_from_proc_cmdline();
+                        k = parse_fstab(true);
+                        if (k < 0)
+                                r = k;
+                }
+        }
 
-        if (!arg_enabled)
-                return EXIT_SUCCESS;
+        free(arg_root_what);
+        free(arg_root_fstype);
+        free(arg_root_options);
 
-        r = parse_fstab();
+        free(arg_usr_what);
+        free(arg_usr_fstype);
+        free(arg_usr_options);
 
-        return (r < 0) || (k < 0) ? EXIT_FAILURE : EXIT_SUCCESS;
+        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 }