generators: rework mount generators

- Add support for finding and mounting /srv based on GPT data, similar
  to how we already handly /home.

- Share the fsck logic between GPT, EFI and fstab generators

- Make sure we never run the EFI generator inside containers

- Drop DefaultDependencies=no from EFI mount units

- Other fixes

7 files changed, 334 insertions, 168 deletions

diff --git a/Makefile.am b/Makefile.am
index f99cef7a17..6cc83162dd 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -792,7 +792,10 @@ libsystemd_shared_la_SOURCES = \
 	src/shared/condition-util.c \
 	src/shared/condition-util.h \
 	src/shared/bus-label.c \
-	src/shared/bus-label.h
+	src/shared/bus-label.h \
+	src/shared/gpt.h \
+	src/shared/generator.h \
+	src/shared/generator.c
 
 nodist_libsystemd_shared_la_SOURCES = \
 	src/shared/errno-from-name.h \
diff --git a/src/efi-boot-generator/efi-boot-generator.c b/src/efi-boot-generator/efi-boot-generator.c
index 606d35bf79..270dc226ef 100644
--- a/src/efi-boot-generator/efi-boot-generator.c
+++ b/src/efi-boot-generator/efi-boot-generator.c
@@ -27,15 +27,18 @@
 #include "util.h"
 #include "mkdir.h"
 #include "unit-name.h"
+#include "virt.h"
+#include "generator.h"
+#include "special.h"
 
 static const char *arg_dest = "/tmp";
 
 int main(int argc, char *argv[]) {
+        _cleanup_free_ char *what = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
         int r = EXIT_SUCCESS;
         sd_id128_t id;
-        _cleanup_free_ char *what = NULL, *fsck = NULL;
         char *name;
-        _cleanup_fclose_ FILE *f = NULL, *f2 = NULL;
 
         if (argc > 1 && argc != 4) {
                 log_error("This program takes three or no arguments.");
@@ -51,16 +54,30 @@ int main(int argc, char *argv[]) {
 
         umask(0022);
 
-        if (!is_efi_boot())
+        if (in_initrd()) {
+                log_debug("In initrd, exiting.");
                 return EXIT_SUCCESS;
+        }
+        if (detect_container(NULL) > 0) {
+                log_debug("In a container, exiting.");
+                return EXIT_SUCCESS;
+        }
 
-        if (dir_is_empty("/boot") <= 0)
+        if (!is_efi_boot()) {
+                log_debug("Not an EFI boot, exiting.");
                 return EXIT_SUCCESS;
+        }
+
+        if (dir_is_empty("/boot") <= 0) {
+                log_debug("/boot already populated, exiting.");
+                return EXIT_SUCCESS;
+        }
 
         r = efi_loader_get_device_part_uuid(&id);
-        if (r == -ENOENT)
+        if (r == -ENOENT) {
+                log_debug("EFI loader partition unknown exiting.");
                 return EXIT_SUCCESS;
-        if (r < 0) {
+        } else if (r < 0) {
                 log_error("Failed to read ESP partition UUID: %s", strerror(-r));
                 return EXIT_FAILURE;
         }
@@ -80,28 +97,34 @@ int main(int argc, char *argv[]) {
                 return EXIT_FAILURE;
         }
 
-        fsck = unit_name_from_path_instance("systemd-fsck", what, ".service");
-        if (!fsck) {
-                log_oom();
-                return EXIT_FAILURE;
-        }
-
         fprintf(f,
                 "# Automatially generated by systemd-efi-boot-generator\n\n"
                 "[Unit]\n"
-                "Description=EFI System Partition\n"
-                "Requires=%s\n"
-                "After=%s\n"
+                "Description=EFI System Partition\n");
+
+        r = generator_write_fsck_deps(f, arg_dest, what, "/boot", "vfat");
+        if (r < 0)
+                return EXIT_FAILURE;
+
+        fprintf(f,
                 "\n"
                 "[Mount]\n"
-                "Where=/boot\n"
                 "What=%s\n"
+                "Where=/boot\n"
+                "Type=vfat\n"
                 "Options=umask=0077,noauto\n",
-                fsck, fsck, what);
+                what);
+
+        fflush(f);
+        if (ferror(f)) {
+                log_error("Failed to write mount unit file: %m");
+                return EXIT_FAILURE;
+        }
 
         name = strappenda(arg_dest, "/boot.automount");
-        f2 = fopen(name, "wxe");
-        if (!f2) {
+        fclose(f);
+        f = fopen(name, "wxe");
+        if (!f) {
                 log_error("Failed to create automount unit file %s: %m", name);
                 return EXIT_FAILURE;
         }
@@ -110,9 +133,15 @@ int main(int argc, char *argv[]) {
               "[Unit]\n"
               "Description=EFI System Partition Automount\n\n"
               "[Automount]\n"
-              "Where=/boot\n", f2);
+              "Where=/boot\n", f);
+
+        fflush(f);
+        if (ferror(f)) {
+                log_error("Failed to write automount unit file: %m");
+                return EXIT_FAILURE;
+        }
 
-        name = strappenda(arg_dest, "/local-fs.target.wants/boot.automount");
+        name = strappenda(arg_dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/boot.automount");
         mkdir_parents(name, 0755);
 
         if (symlink("../boot.automount", name) < 0) {
diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index 5521a864df..aac1a436ec 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -33,9 +33,10 @@
 #include "special.h"
 #include "mkdir.h"
 #include "fileio.h"
+#include "generator.h"
 
 static const char *arg_dest = "/tmp";
-static bool arg_enabled = true;
+static bool arg_fstab_enabled = true;
 
 static int mount_find_pri(struct mntent *me, int *ret) {
         char *end, *pri;
@@ -146,57 +147,6 @@ static bool mount_in_initrd(struct mntent *me) {
                 streq(me->mnt_dir, "/usr");
 }
 
-static int add_fsck(FILE *f, const char *what, const char *where, const char *type, int passno) {
-        assert(f);
-
-        if (passno == 0)
-                return 0;
-
-        if (!is_device_path(what)) {
-                log_warning("Checking was requested for \"%s\", but it is not a device.", what);
-                return 0;
-        }
-
-        if (type && !streq(type, "auto")) {
-                int r;
-                const char *checker;
-
-                checker = strappenda("/sbin/fsck.", type);
-                r = access(checker, X_OK);
-                if (r < 0) {
-                        log_warning("Checking was requested for %s, but %s cannot be used: %m", what, checker);
-
-                        /* treat missing check as essentially OK */
-                        return errno == ENOENT ? 0 : -errno;
-                }
-        }
-
-        if (streq(where, "/")) {
-                char *lnk;
-
-                lnk = strappenda(arg_dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/systemd-fsck-root.service");
-                mkdir_parents_label(lnk, 0755);
-                if (symlink(SYSTEM_DATA_UNIT_PATH "/systemd-fsck-root.service", lnk) < 0) {
-                        log_error("Failed to create symlink %s: %m", lnk);
-                        return -errno;
-                }
-        } else {
-                _cleanup_free_ char *fsck = NULL;
-
-                fsck = unit_name_from_path_instance("systemd-fsck", what, ".service");
-                if (!fsck)
-                        return log_oom();
-
-                fprintf(f,
-                        "RequiresOverridable=%s\n"
-                        "After=%s\n",
-                        fsck,
-                        fsck);
-        }
-
-        return 0;
-}
-
 static int add_mount(
                 const char *what,
                 const char *where,
@@ -208,6 +158,7 @@ static int add_mount(
                 bool automount,
                 const char *post,
                 const char *source) {
+
         _cleanup_free_ char
                 *name = NULL, *unit = NULL, *lnk = NULL,
                 *automount_name = NULL, *automount_unit = NULL;
@@ -232,6 +183,12 @@ static int add_mount(
             mount_point_ignore(where))
                 return 0;
 
+        if (path_equal(where, "/")) {
+                automount = false;
+                noauto = false;
+                nofail = false;
+        }
+
         name = unit_name_from_path(where, ".mount");
         if (!name)
                 return log_oom();
@@ -260,9 +217,11 @@ static int add_mount(
                         "Before=%s\n",
                         post);
 
-        r = add_fsck(f, what, where, type, passno);
-        if (r < 0)
-                return r;
+        if (passno != 0) {
+                r = generator_write_fsck_deps(f, arg_dest, what, where, type);
+                if (r < 0)
+                        return r;
+        }
 
         fprintf(f,
                 "\n"
@@ -274,8 +233,7 @@ static int add_mount(
                 where,
                 type);
 
-        if (!isempty(opts) &&
-            !streq(opts, "defaults"))
+        if (!isempty(opts) && !streq(opts, "defaults"))
                 fprintf(f,
                         "Options=%s\n",
                         opts);
@@ -300,7 +258,7 @@ static int add_mount(
                 }
         }
 
-        if (automount && !path_equal(where, "/")) {
+        if (automount) {
                 automount_name = unit_name_from_path(where, ".automount");
                 if (!automount_name)
                         return log_oom();
@@ -324,7 +282,7 @@ static int add_mount(
 
                 if (post)
                         fprintf(f,
-                                "Before= %s\n",
+                                "Before=%s\n",
                                 post);
 
                 fprintf(f,
@@ -353,19 +311,19 @@ static int add_mount(
         return 0;
 }
 
-static int parse_fstab(const char *prefix, bool initrd) {
-        char *fstab_path;
+static int parse_fstab(bool initrd) {
         _cleanup_endmntent_ FILE *f;
-        int r = 0;
+        const char *fstab_path;
         struct mntent *me;
+        int r = 0;
 
-        fstab_path = strappenda(strempty(prefix), "/etc/fstab");
-        f = setmntent(fstab_path, "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 %s/etc/fstab: %m", strempty(prefix));
+                log_error("Failed to open %s: %m", fstab_path);
                 return -errno;
         }
 
@@ -377,8 +335,11 @@ static int parse_fstab(const char *prefix, bool initrd) {
                         continue;
 
                 what = fstab_node_to_udev_node(me->mnt_fsname);
-                where = strjoin(strempty(prefix), me->mnt_dir, NULL);
-                if (!what || !where)
+                if (!what)
+                        return log_oom();
+
+                where = initrd ? strappend("/sysroot/", me->mnt_dir) : strdup(me->mnt_dir);
+                if (!where)
                         return log_oom();
 
                 if (is_path(where))
@@ -398,15 +359,14 @@ static int parse_fstab(const char *prefix, bool initrd) {
                                   hasmntopt(me, "comment=systemd.automount") ||
                                   hasmntopt(me, "x-systemd.automount");
 
-                        if (initrd) {
+                        if (initrd)
                                 post = SPECIAL_INITRD_FS_TARGET;
-                        } else if (mount_in_initrd(me)) {
+                        else if (mount_in_initrd(me))
                                 post = SPECIAL_INITRD_ROOT_FS_TARGET;
-                        } else if (mount_is_network(me)) {
+                        else if (mount_is_network(me))
                                 post = SPECIAL_REMOTE_FS_TARGET;
-                        } else {
+                        else
                                 post = SPECIAL_LOCAL_FS_TARGET;
-                        }
 
                         k = add_mount(what, where, me->mnt_type, me->mnt_opts,
                                       me->mnt_passno, noauto, nofail, automount,
@@ -505,11 +465,12 @@ static int parse_proc_cmdline_word(const char *word) {
         int r;
 
         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;
+                        arg_fstab_enabled = r;
 
         } else if (startswith(word, "rd.fstab=")) {
 
@@ -518,7 +479,7 @@ static int parse_proc_cmdline_word(const char *word) {
                         if (r < 0)
                                 log_warning("Failed to parse fstab switch %s. Ignoring.", word + 9);
                         else
-                                arg_enabled = r;
+                                arg_fstab_enabled = r;
                 }
 
         } else if (startswith(word, "fstab.") ||
@@ -531,7 +492,7 @@ static int parse_proc_cmdline_word(const char *word) {
 }
 
 int main(int argc, char *argv[]) {
-        int r = 0, k, l = 0;
+        int r = 0;
 
         if (argc > 1 && argc != 4) {
                 log_error("This program takes three or no arguments.");
@@ -550,16 +511,26 @@ int main(int argc, char *argv[]) {
         if (parse_proc_cmdline(parse_proc_cmdline_word) < 0)
                 return EXIT_FAILURE;
 
+        /* Always honour root= in the kernel command line if we are in an initrd */
         if (in_initrd())
                 r = parse_new_root_from_proc_cmdline();
 
-        if (!arg_enabled)
-                return (r < 0) ? EXIT_FAILURE : EXIT_SUCCESS;
+        /* Honour /etc/fstab only when that's enabled */
+        if (arg_fstab_enabled) {
+                int k;
 
-        k = parse_fstab(NULL, false);
+                /* Parse the local /etc/fstab, possibly from the initrd */
+                k = parse_fstab(false);
+                if (k < 0)
+                        r = k;
 
-        if (in_initrd())
-                l = parse_fstab("/sysroot", true);
+                /* If running in the initrd also parse the /etc/fstab from the host */
+                if (in_initrd()) {
+                        k = parse_fstab(true);
+                        if (k < 0)
+                                r = k;
+                }
+        }
 
-        return (r < 0) || (k < 0) || (l < 0) ? EXIT_FAILURE : EXIT_SUCCESS;
+        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 }
diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c
index 05934da82f..f34cd030c2 100644
--- a/src/gpt-auto-generator/gpt-auto-generator.c
+++ b/src/gpt-auto-generator/gpt-auto-generator.c
@@ -40,6 +40,8 @@
 #include "special.h"
 #include "unit-name.h"
 #include "virt.h"
+#include "generator.h"
+#include "gpt.h"
 
 /* TODO:
  *
@@ -49,9 +51,6 @@
  *
  */
 
-#define GPT_SWAP SD_ID128_MAKE(06,57,fd,6d,a4,ab,43,c4,84,e5,09,33,c8,4b,4f,4f)
-#define GPT_HOME SD_ID128_MAKE(93,3a,c7,e1,2e,b4,4f,13,b8,44,0e,14,e2,ae,f9,15)
-
 static const char *arg_dest = "/tmp";
 
 DEFINE_TRIVIAL_CLEANUP_FUNC(blkid_probe, blkid_free_probe);
@@ -152,10 +151,6 @@ static int add_swap(const char *path, const char *fstype) {
 
         fprintf(f,
                 "# Automatically generated by systemd-gpt-auto-generator\n\n"
-                "[Unit]\n"
-                "DefaultDependencies=no\n"
-                "Conflicts=" SPECIAL_UMOUNT_TARGET "\n"
-                "Before=" SPECIAL_UMOUNT_TARGET " " SPECIAL_SWAP_TARGET "\n\n"
                 "[Swap]\n"
                 "What=%s\n",
                 path);
@@ -179,42 +174,49 @@ static int add_swap(const char *path, const char *fstype) {
         return 0;
 }
 
-static int add_home(const char *path, const char *fstype) {
-        _cleanup_free_ char *unit = NULL, *lnk = NULL, *fsck = NULL;
+static int add_mount(const char *what, const char *where, const char *fstype, const char *description) {
+        _cleanup_free_ char *unit = NULL, *lnk = NULL, *p = NULL;
         _cleanup_fclose_ FILE *f = NULL;
+        int r;
 
-        if (dir_is_empty("/home") <= 0)
+        if (dir_is_empty(where) <= 0) {
+                log_debug("%s already populated, ignoring.", where);
                 return 0;
+        }
 
-        log_debug("Adding home: %s %s", path, fstype);
+        log_debug("Adding %s: %s %s", where, what, fstype);
 
-        unit = strappend(arg_dest, "/home.mount");
+        unit = unit_name_from_path(where, ".mount");
         if (!unit)
                 return log_oom();
 
-        f = fopen(unit, "wxe");
+        p = strjoin(arg_dest, "/", unit, NULL);
+        if (!p)
+                return log_oom();
+
+        f = fopen(p, "wxe");
         if (!f) {
                 log_error("Failed to create unit file %s: %m", unit);
                 return -errno;
         }
 
-        fsck = unit_name_from_path_instance("systemd-fsck", path, ".service");
-        if (!fsck)
-                return log_oom();
-
         fprintf(f,
                 "# Automatically generated by systemd-gpt-auto-generator\n\n"
                 "[Unit]\n"
-                "DefaultDependencies=no\n"
-                "Requires=%s\n"
-                "After=" SPECIAL_LOCAL_FS_PRE_TARGET " %s\n"
-                "Conflicts=" SPECIAL_UMOUNT_TARGET "\n"
-                "Before=" SPECIAL_UMOUNT_TARGET " " SPECIAL_LOCAL_FS_TARGET "\n\n"
+                "Description=%s\n",
+                description);
+
+        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=/home\n"
+                "Where=%s\n"
                 "Type=%s\n",
-                fsck, fsck, path, fstype);
+                what, where, fstype);
 
         fflush(f);
         if (ferror(f)) {
@@ -222,7 +224,7 @@ static int add_home(const char *path, const char *fstype) {
                 return -errno;
         }
 
-        lnk = strjoin(arg_dest, "/" SPECIAL_LOCAL_FS_TARGET ".requires/home.mount", NULL);
+        lnk = strjoin(arg_dest, "/" SPECIAL_LOCAL_FS_TARGET ".requires/", unit, NULL);
         if (!lnk)
                 return log_oom();
 
@@ -236,12 +238,12 @@ static int add_home(const char *path, const char *fstype) {
 }
 
 static int enumerate_partitions(struct udev *udev, dev_t dev) {
-        struct udev_device *parent = NULL;
         _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
         _cleanup_udev_device_unref_ struct udev_device *d = NULL;
+        _cleanup_free_ char *home = NULL, *home_fstype = NULL, *srv = NULL, *srv_fstype = NULL;
+        unsigned home_nr = (unsigned) -1, srv_nr = (unsigned )-1;
         struct udev_list_entry *first, *item;
-        unsigned home_nr = (unsigned) -1;
-        _cleanup_free_ char *home = NULL, *home_fstype = NULL;
+        struct udev_device *parent = NULL;
         int r;
 
         e = udev_enumerate_new(udev);
@@ -266,16 +268,15 @@ static int enumerate_partitions(struct udev *udev, dev_t dev) {
 
         r = udev_enumerate_scan_devices(e);
         if (r < 0) {
-                log_error("Failed to enumerate partitions on /dev/block/%u:%u: %s",
-                          major(dev), minor(dev), strerror(-r));
+                log_error("Failed to enumerate partitions on /dev/block/%u:%u: %s", major(dev), minor(dev), strerror(-r));
                 return r;
         }
 
         first = udev_enumerate_get_list_entry(e);
         udev_list_entry_foreach(item, first) {
+                _cleanup_udev_device_unref_ struct udev_device *q;
                 _cleanup_free_ char *fstype = NULL;
                 const char *node = NULL;
-                _cleanup_udev_device_unref_ struct udev_device *q;
                 sd_id128_t type_id;
                 unsigned nr;
 
@@ -298,8 +299,7 @@ static int enumerate_partitions(struct udev *udev, dev_t dev) {
                         /* skip child devices which are not detected properly */
                         if (r == -EBADSLT)
                                 continue;
-                        log_error("Failed to verify GPT partition %s: %s",
-                                  node, strerror(-r));
+                        log_error("Failed to verify GPT partition %s: %s", node, strerror(-r));
                         return r;
                 }
                 if (r == 0)
@@ -307,24 +307,48 @@ static int enumerate_partitions(struct udev *udev, dev_t dev) {
 
                 if (sd_id128_equal(type_id, GPT_SWAP))
                         add_swap(node, fstype);
+
                 else if (sd_id128_equal(type_id, GPT_HOME)) {
-                        if (!home || nr < home_nr) {
-                                free(home);
-                                home = strdup(node);
-                                if (!home)
-                                        return log_oom();
-
-                                home_nr = nr;
-
-                                free(home_fstype);
-                                home_fstype = fstype;
-                                fstype = NULL;
-                        }
+
+                        /* We only care for the first /home partition */
+                        if (home && nr >= home_nr)
+                                continue;
+
+                        home_nr = nr;
+
+                        free(home);
+                        home = strdup(node);
+                        if (!home)
+                                return log_oom();
+
+                        free(home_fstype);
+                        home_fstype = fstype;
+                        fstype = NULL;
+
+                } else if (sd_id128_equal(type_id, GPT_SRV)) {
+
+                        /* We only care for the first /srv partition */
+                        if (srv && nr >= srv_nr)
+                                continue;
+
+                        srv_nr = nr;
+
+                        free(srv);
+                        srv = strdup(node);
+                        if (!srv)
+                                return log_oom();
+
+                        free(srv_fstype);
+                        srv_fstype = fstype;
+                        fstype = NULL;
                 }
         }
 
         if (home && home_fstype)
-                add_home(home, home_fstype);
+                add_mount(home, "/home", home_fstype, "Home Partition");
+
+        if (srv && srv_fstype)
+                add_mount(srv, "/srv", srv_fstype, "Server Data Partition");
 
         return r;
 }
@@ -384,7 +408,7 @@ static int get_block_device(const char *path, dev_t *dev) {
         assert(path);
         assert(dev);
 
-        if (lstat("/", &st))
+        if (lstat(path, &st))
                 return -errno;
 
         if (major(st.st_dev) != 0) {
@@ -392,7 +416,7 @@ static int get_block_device(const char *path, dev_t *dev) {
                 return 1;
         }
 
-        if (statfs("/", &sfs) < 0)
+        if (statfs(path, &sfs) < 0)
                 return -errno;
 
         if (F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC))
@@ -423,15 +447,14 @@ static int devno_to_devnode(struct udev *udev, dev_t devno, char **ret) {
 }
 
 int main(int argc, char *argv[]) {
-        _cleanup_free_ char *node = NULL;
         _cleanup_udev_unref_ struct udev *udev = NULL;
+        _cleanup_free_ char *node = NULL;
         dev_t devno;
         int r = 0;
 
         if (argc > 1 && argc != 4) {
                 log_error("This program takes three or no arguments.");
-                r = -EINVAL;
-                goto finish;
+                return EXIT_FAILURE;
         }
 
         if (argc > 1)
@@ -445,34 +468,33 @@ int main(int argc, char *argv[]) {
 
         if (in_initrd()) {
                 log_debug("In initrd, exiting.");
-                goto finish;
+                return EXIT_SUCCESS;
         }
 
         if (detect_container(NULL) > 0) {
                 log_debug("In a container, exiting.");
-                goto finish;
+                return EXIT_SUCCESS;
         }
 
         r = get_block_device("/", &devno);
         if (r < 0) {
                 log_error("Failed to determine block device of root file system: %s", strerror(-r));
-                goto finish;
-        }
-        if (r == 0) {
+                return EXIT_FAILURE;
+        } else if (r == 0) {
                 log_debug("Root file system not on a (single) block device.");
-                goto finish;
+                return EXIT_SUCCESS;
         }
 
         udev = udev_new();
         if (!udev) {
-                r = log_oom();
-                goto finish;
+                log_oom();
+                return EXIT_FAILURE;
         }
 
         r = devno_to_devnode(udev, devno, &node);
         if (r < 0) {
                 log_error("Failed to determine block device node from major/minor: %s", strerror(-r));
-                goto finish;
+                return EXIT_FAILURE;
         }
 
         log_debug("Root device %s.", node);
@@ -480,13 +502,16 @@ int main(int argc, char *argv[]) {
         r = verify_gpt_partition(node, NULL, NULL, NULL);
         if (r < 0) {
                 log_error("Failed to verify GPT partition %s: %s", node, strerror(-r));
-                goto finish;
+                return EXIT_FAILURE;
+        }
+        if (r == 0) {
+                log_debug("Not a GPT disk, exiting.");
+                return EXIT_SUCCESS;
         }
-        if (r == 0)
-                goto finish;
 
         r = enumerate_partitions(udev, devno);
+        if (r < 0)
+                return EXIT_FAILURE;
 
-finish:
-        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+        return EXIT_SUCCESS;
 }
diff --git a/src/shared/generator.c b/src/shared/generator.c
new file mode 100644
index 0000000000..49647c1ab6
--- /dev/null
+++ b/src/shared/generator.c
@@ -0,0 +1,84 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2014 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <unistd.h>
+
+#include "util.h"
+#include "special.h"
+#include "mkdir.h"
+#include "unit-name.h"
+#include "generator.h"
+
+int generator_write_fsck_deps(
+                FILE *f,
+                const char *dest,
+                const char *what,
+                const char *where,
+                const char *type) {
+
+        assert(f);
+
+        if (!is_device_path(what)) {
+                log_warning("Checking was requested for \"%s\", but it is not a device.", what);
+                return 0;
+        }
+
+        if (type && !streq(type, "auto")) {
+                const char *checker;
+                int r;
+
+                checker = strappenda("/sbin/fsck.", type);
+                r = access(checker, X_OK);
+                if (r < 0) {
+                        log_warning("Checking was requested for %s, but %s cannot be used: %m", what, checker);
+
+                        /* treat missing check as essentially OK */
+                        return errno == ENOENT ? 0 : -errno;
+                }
+        }
+
+        if (streq(where, "/")) {
+                char *lnk;
+
+                lnk = strappenda(dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/systemd-fsck-root.service");
+
+                mkdir_parents(lnk, 0755);
+                if (symlink(SYSTEM_DATA_UNIT_PATH "/systemd-fsck-root.service", lnk) < 0) {
+                        log_error("Failed to create symlink %s: %m", lnk);
+                        return -errno;
+                }
+
+        } else {
+                _cleanup_free_ char *fsck = NULL;
+
+                fsck = unit_name_from_path_instance("systemd-fsck", what, ".service");
+                if (!fsck)
+                        return log_oom();
+
+                fprintf(f,
+                        "RequiresOverridable=%s\n"
+                        "After=%s\n",
+                        fsck,
+                        fsck);
+        }
+
+        return 0;
+}
diff --git a/src/shared/generator.h b/src/shared/generator.h
new file mode 100644
index 0000000000..0140aa943f
--- /dev/null
+++ b/src/shared/generator.h
@@ -0,0 +1,26 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2014 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+
+int generator_write_fsck_deps(FILE *f, const char *dest, const char *what, const char *where, const char *type);
diff --git a/src/shared/gpt.h b/src/shared/gpt.h
new file mode 100644
index 0000000000..2956377b48
--- /dev/null
+++ b/src/shared/gpt.h
@@ -0,0 +1,28 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2014 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "sd-id128.h"
+
+#define GPT_ESP  SD_ID128_MAKE(c1,2a,73,28,f8,1f,11,d2,ba,4b,00,a0,c9,3e,c9,3b)
+#define GPT_ROOT SD_ID128_MAKE(4f,68,bc,e3,e8,cd,4d,b1,96,e7,fb,ca,f9,84,b7,09)
+#define GPT_SWAP SD_ID128_MAKE(06,57,fd,6d,a4,ab,43,c4,84,e5,09,33,c8,4b,4f,4f)
+#define GPT_HOME SD_ID128_MAKE(93,3a,c7,e1,2e,b4,4f,13,b8,44,0e,14,e2,ae,f9,15)
+#define GPT_SRV  SD_ID128_MAKE(3b,8f,84,25,20,e0,4f,3b,90,7f,1a,25,a7,6f,98,e8)