Add x-systemd.growfs option for fstab

3 files changed, 76 insertions, 5 deletions

diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index 5bdeae04c3..68e7c23cbe 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -52,6 +52,7 @@ typedef enum MountpointFlags {
         NOFAIL    = 1 << 1,
         AUTOMOUNT = 1 << 2,
         MAKEFS    = 1 << 3,
+        GROWFS    = 1 << 4,
 } MountpointFlags;
 
 static const char *arg_dest = "/tmp";
@@ -162,6 +163,10 @@ static int add_swap(
                         return r;
         }
 
+        if (flags & GROWFS)
+                /* TODO: swap devices must be wiped and recreated */
+                log_warning("%s: growing swap devices is currently unsupported.", what);
+
         if (!(flags & NOAUTO)) {
                 r = generator_add_symlink(arg_dest, SPECIAL_SWAP_TARGET,
                                           (flags & NOFAIL) ? "wants" : "requires", name);
@@ -459,6 +464,12 @@ static int add_mount(
                         return r;
         }
 
+        if (flags & GROWFS) {
+                r = generator_hook_up_growfs(dest, where, post);
+                if (r < 0)
+                        return r;
+        }
+
         if (!(flags & NOAUTO) && !(flags & AUTOMOUNT)) {
                 r = generator_add_symlink(dest, post,
                                           (flags & NOFAIL) ? "wants" : "requires", name);
@@ -544,7 +555,7 @@ static int parse_fstab(bool initrd) {
 
         while ((me = getmntent(f))) {
                 _cleanup_free_ char *where = NULL, *what = NULL, *canonical_where = NULL;
-                bool makefs, noauto, nofail;
+                bool makefs, growfs, noauto, nofail;
                 int k;
 
                 if (initrd && !mount_in_initrd(me))
@@ -587,6 +598,7 @@ static int parse_fstab(bool initrd) {
                 }
 
                 makefs = fstab_test_option(me->mnt_opts, "x-systemd.makefs\0");
+                growfs = fstab_test_option(me->mnt_opts, "x-systemd.growfs\0");
                 noauto = fstab_test_yes_no_option(me->mnt_opts, "noauto\0" "auto\0");
                 nofail = fstab_test_yes_no_option(me->mnt_opts, "nofail\0" "fail\0");
                 log_debug("Found entry what=%s where=%s type=%s makefs=%s nofail=%s noauto=%s",
@@ -596,7 +608,7 @@ static int parse_fstab(bool initrd) {
 
                 if (streq(me->mnt_type, "swap"))
                         k = add_swap(what, me,
-                                     makefs*MAKEFS | noauto*NOAUTO | nofail*NOFAIL);
+                                     makefs*MAKEFS | growfs*GROWFS | noauto*NOAUTO | nofail*NOFAIL);
                 else {
                         bool automount;
                         const char *post;
@@ -618,12 +630,12 @@ static int parse_fstab(bool initrd) {
                                       me->mnt_type,
                                       me->mnt_opts,
                                       me->mnt_passno,
-                                      makefs*MAKEFS | noauto*NOAUTO | nofail*NOFAIL | automount*AUTOMOUNT,
+                                      makefs*MAKEFS | growfs*GROWFS | noauto*NOAUTO | nofail*NOFAIL | automount*AUTOMOUNT,
                                       post,
                                       fstab_path);
                 }
 
-                if (k < 0)
+                if (r >= 0 && k < 0)
                         r = k;
         }
 
@@ -679,7 +691,7 @@ static int add_sysroot_mount(void) {
                          arg_root_fstype,
                          opts,
                          is_device_path(what) ? 1 : 0, /* passno */
-                         0,                            /* makefs off, noauto off, nofail off, automount off */
+                         0,                            /* makefs off, growfs off, noauto off, nofail off, automount off */
                          SPECIAL_INITRD_ROOT_FS_TARGET,
                          "/proc/cmdline");
 }
diff --git a/src/shared/generator.c b/src/shared/generator.c
index 7c764328d6..3495a7ef7d 100644
--- a/src/shared/generator.c
+++ b/src/shared/generator.c
@@ -427,3 +427,58 @@ int generator_hook_up_mkfs(
 
         return generator_add_symlink(dir, where_unit, "requires", unit);
 }
+
+int generator_hook_up_growfs(
+                const char *dir,
+                const char *where,
+                const char *target) {
+
+        _cleanup_free_ char *unit = NULL, *escaped = NULL, *where_unit = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        const char *unit_file;
+        int r;
+
+        escaped = cescape(where);
+        if (!escaped)
+                return log_oom();
+
+        r = unit_name_from_path_instance("systemd-growfs", where, ".service", &unit);
+        if (r < 0)
+                return log_error_errno(r, "Failed to make unit instance name from path \"%s\": %m",
+                                       where);
+
+        r = unit_name_from_path(where, ".mount", &where_unit);
+        if (r < 0)
+                return log_error_errno(r, "Failed to make unit name from path \"%s\": %m",
+                                       where);
+
+        unit_file = strjoina(dir, "/", unit);
+        log_debug("Creating %s", unit_file);
+
+        f = fopen(unit_file, "wxe");
+        if (!f)
+                return log_error_errno(errno, "Failed to create unit file %s: %m",
+                                       unit_file);
+
+        fprintf(f,
+                "# Automatically generated by %s\n\n"
+                "[Unit]\n"
+                "Description=Grow File System on %%f\n"
+                "Documentation=man:systemd-growfs@.service(8)\n"
+                "DefaultDependencies=no\n"
+                "BindsTo=%%i.mount\n"
+                "After=%%i.mount\n"
+                "Before=shutdown.target\n"
+                "Before=%s\n"
+                "\n"
+                "[Service]\n"
+                "Type=oneshot\n"
+                "RemainAfterExit=yes\n"
+                "ExecStart="SYSTEMD_GROWFS_PATH " %s\n"
+                "TimeoutSec=0\n",
+                program_invocation_short_name,
+                target,
+                escaped);
+
+        return generator_add_symlink(dir, where_unit, "wants", unit);
+}
diff --git a/src/shared/generator.h b/src/shared/generator.h
index f4109b95a3..32d1ad021c 100644
--- a/src/shared/generator.h
+++ b/src/shared/generator.h
@@ -56,3 +56,7 @@ int generator_hook_up_mkfs(
         const char *what,
         const char *where,
         const char *type);
+int generator_hook_up_growfs(
+        const char *dir,
+        const char *where,
+        const char *target);