Merge pull request #17822 from abbradar/systemd-mounts

nixos filesystems: unify special filesystems handling

nixos/modules/system/activation/activation-script.nix

@@ -154,9 +154,15 @@ in
 
     system.activationScripts.tmpfs =
       ''
-        ${pkgs.utillinux}/bin/mount -o "remount,size=${config.boot.devSize}" none /dev
-        ${pkgs.utillinux}/bin/mount -o "remount,size=${config.boot.devShmSize}" none /dev/shm
-        ${pkgs.utillinux}/bin/mount -o "remount,size=${config.boot.runSize}" none /run
+        specialMount() {
+          local device="$1"
+          local mountPoint="$2"
+          local options="$3"
+          local fsType="$4"
+
+          ${pkgs.utillinux}/bin/mount -t "$fsType" -o "remount,$options" "$device" "$mountPoint"
+        }
+        source ${config.system.build.earlyMountScript}
       '';
 
   };

nixos/modules/system/boot/stage-1-init.sh

@@ -59,22 +59,24 @@ echo
 echo "<<< NixOS Stage 1 >>>"
 echo
 
-
-# Mount special file systems.
+# Make several required directories.
 mkdir -p /etc/udev
 touch /etc/fstab # to shut up mount
-touch /etc/mtab # to shut up mke2fs
+ln -s /proc/mounts /etc/mtab # to shut up mke2fs
 touch /etc/udev/hwdb.bin # to shut up udev
 touch /etc/initrd-release
-mkdir -p /proc
-mount -t proc proc /proc
-mkdir -p /sys
-mount -t sysfs sysfs /sys
-mount -t devtmpfs -o "size=@devSize@" devtmpfs /dev
-mkdir -p /run
-mount -t tmpfs -o "mode=0755,size=@runSize@" tmpfs /run
-mkdir /dev/pts
-mount -t devpts devpts /dev/pts
+
+# Mount special file systems.
+specialMount() {
+  local device="$1"
+  local mountPoint="$2"
+  local options="$3"
+  local fsType="$4"
+
+  mkdir -m 0755 -p "$mountPoint"
+  mount -n -t "$fsType" -o "$options" "$device" "$mountPoint"
+}
+source @earlyMountScript@
 
 # Log the script output to /dev/kmsg or /run/log/stage-1-init.log.
 mkdir -p /tmp

nixos/modules/system/boot/stage-1.nix

@@ -190,7 +190,9 @@ let
 
     inherit udevRules extraUtils modulesClosure;
 
-    inherit (config.boot) resumeDevice devSize runSize;
+    inherit (config.boot) resumeDevice;
+
+    inherit (config.system.build) earlyMountScript;
 
     inherit (config.boot.initrd) checkJournalingFS
       preLVMCommands preDeviceCommands postDeviceCommands postMountCommands preFailCommands kernelModules;

nixos/modules/system/boot/stage-2-init.sh

@@ -37,12 +37,16 @@ fi
 # Likewise, stage 1 mounts /proc, /dev and /sys, so if we don't have a
 # stage 1, we need to do that here.
 if [ ! -e /proc/1 ]; then
-    mkdir -m 0755 -p /proc
-    mount -n -t proc proc /proc
-    mkdir -m 0755 -p /dev
-    mount -t devtmpfs devtmpfs /dev
-    mkdir -m 0755 -p /sys
-    mount -t sysfs sysfs /sys
+    specialMount() {
+        local device="$1"
+        local mountPoint="$2"
+        local options="$3"
+        local fsType="$4"
+
+        mkdir -m 0755 -p "$mountPoint"
+        mount -n -t "$fsType" -o "$options" "$device" "$mountPoint"
+    }
+    source @earlyMountScript@
 fi
 
 
@@ -87,11 +91,6 @@ done
 
 
 # More special file systems, initialise required directories.
-if ! mountpoint -q /dev/shm; then
-    mkdir -m 0755 /dev/shm
-    mount -t tmpfs -o "rw,nosuid,nodev,size=@devShmSize@" tmpfs /dev/shm
-fi
-mkdir -m 0755 -p /dev/pts
 [ -e /proc/bus/usb ] && mount -t usbfs usbfs /proc/bus/usb # UML doesn't have USB by default
 mkdir -m 01777 -p /tmp
 mkdir -m 0755 -p /var /var/log /var/lib /var/db
@@ -112,14 +111,6 @@ rm -f /etc/{group,passwd,shadow}.lock
 rm -rf /nix/var/nix/gcroots/tmp /nix/var/nix/temproots
 
 
-# Create a tmpfs on /run to hold runtime state for programs such as
-# udev (if stage 1 hasn't already done so).
-if ! mountpoint -q /run; then
-    rm -rf /run
-    mkdir -m 0755 -p /run
-    mount -t tmpfs -o "mode=0755,size=@runSize@" tmpfs /run
-fi
-
 # Create a ramfs on /run/keys to hold secrets that shouldn't be
 # written to disk (generally used for NixOps, harmless elsewhere).
 if ! mountpoint -q /run/keys; then

nixos/modules/system/boot/stage-2.nix

@@ -20,10 +20,9 @@ let
     src = ./stage-2-init.sh;
     shellDebug = "${pkgs.bashInteractive}/bin/bash";
     isExecutable = true;
-    inherit (config.boot) devShmSize runSize;
     inherit (config.nix) readOnlyStore;
     inherit (config.networking) useHostResolvConf;
-    ttyGid = config.ids.gids.tty;
+    inherit (config.system.build) earlyMountScript;
     path =
       [ pkgs.coreutils
         pkgs.utillinux