diff --git a/nixos/modules/config/swap.nix b/nixos/modules/config/swap.nix index f0353c5a35e..62b6e011713 100644 --- a/nixos/modules/config/swap.nix +++ b/nixos/modules/config/swap.nix @@ -30,8 +30,7 @@ let description = '' If this option is set, ‘device’ is interpreted as the path of a swapfile that will be created automatically - with the indicated size (in megabytes) if it doesn't - exist. + with the indicated size (in megabytes). ''; }; @@ -132,9 +131,13 @@ in script = '' ${optionalString (sw.size != null) '' - if [ ! -e "${sw.device}" ]; then + currentSize=$(( $(stat -c "%s" "${sw.device}" 2>/dev/null || echo 0) / 1024 / 1024 )) + if [ "${toString sw.size}" != "$currentSize" ]; then fallocate -l ${toString sw.size}M "${sw.device}" || dd if=/dev/zero of="${sw.device}" bs=1M count=${toString sw.size} + if [ "${toString sw.size}" -lt "$currentSize" ]; then + truncate --size "${toString sw.size}M" "${sw.device}" + fi chmod 0600 ${sw.device} ${optionalString (!sw.randomEncryption) "mkswap ${sw.realDevice}"} fi