guix-daemon.service.in: Make service restartable.

Currently the service cannot be restarted, because the gnu store mount makes
it read-only. So fix this by removing the mount when starting the service.

"-" to accept failures, in case the command doesn't finish successfully,
chances are, the store can be mounted as RW, so continue.
"+" to run as root

Fixes: #4744

* etc/guix-daemon.service.in
(Service)<ExecStartPre>: Stop gnu-store.mount
(Service)<ExecStartPost>: Start gnu-store.mount

Change-Id: I296f5d8805497f8a7364b68d627eb6d4fc05dbff

1 files changed, 6 insertions, 0 deletions

diff --git a/etc/guix-daemon.service.in b/etc/guix-daemon.service.in
index 88929fa904e..869bc4dc0b6 100644
--- a/etc/guix-daemon.service.in
+++ b/etc/guix-daemon.service.in
@@ -14,6 +14,12 @@ ExecStart=@localstatedir@/guix/profiles/per-user/root/current-guix/bin/guix-daem
     --substitute-urls='@GUIX_SUBSTITUTE_URLS@'
 Environment='GUIX_STATE_DIRECTORY=@localstatedir@/guix' 'GUIX_LOCPATH=@localstatedir@/guix/profiles/per-user/root/guix-profile/lib/locale' LC_ALL=en_US.utf8
 
+# Stop the gnu-store.mount so that the daemon can capture the store as
+# read-write in its private mount namespace.
+# See <https://codeberg.org/guix/guix/issues/4744>.
+ExecStartPre=-+systemctl stop gnu-store.mount
+ExecStartPost=-+systemctl start gnu-store.mount --no-block
+
 # Run under a dedicated unprivileged user account.
 User=guix-daemon