feat: do not mount tmp dir for /boot swap

usr/lib/akshara/classes/rootfs.py

@@ -29,6 +29,33 @@ class RootFS:
         """
         return os.path.exists(os.path.join(self.rootfs_path, path))
 
+    def exec_chroot(self, cmd, **kwargs) -> subprocess.CompletedProcess:
+        """Runs command within rootfs using chroot.
+
+        Args:
+            cmd: List comprising command and arguments.
+            **kwargs: Keyword arguments list for subprocess.run().
+        """
+
+        for dir in ("sys, proc", "dev"):
+            subprocess.run(
+                ["mount", "--bind", f"/{dir}", os.path.join(self.rootfs_path, dir)]
+            )
+
+        completedProcess = subprocess.run(
+            [
+                "chroot",
+                self.rootfs_path,
+            ]
+            + list(cmd),
+            **kwargs,
+        )
+
+        for dir in ("sys, proc", "dev"):
+            subprocess.run(["umount", os.path.join(self.rootfs_path, dir)])
+
+        return completedProcess
+
     def exec(self, cmd, **kwargs) -> subprocess.CompletedProcess:
         """Runs command within rootfs.
 

usr/lib/akshara/utils/update.py

@@ -18,6 +18,8 @@ def update_cleanup() -> None:
     for path in (
         "/etc/grub.d",
         "/etc/default/grub",
+        "/var/cache/akshara/rootfs/dev",
+        "/var/cache/akshara/rootfs/proc",
         "/var/cache/akshara/rootfs/var/cache/blendOS",
     ):
         subprocess.run(
@@ -140,31 +142,10 @@ def merge_var(new_rootfs: RootFS, overrides_keep_new: dict) -> None:
                 )
 
 
-def is_bind_mnt(src, mountpoint) -> bool:
-    """Checks if /boot presently has /.tmp.boot bind-mounted to it.
-
-    Args:
-        src: Source directory of bind-mount.
-        mountpoint: Mountpoint for bind-mount.
-    """
-    with open("/proc/self/mountinfo") as mountinfo_file:
-        for line in mountinfo_file:
-            parts = line.strip().split()
-            if parts[3] != "/" and parts[3] == src and parts[4] == mountpoint:
-                return True
-    return False
-
-
 def handle_boot(new_rootfs, boot_config) -> None:
     """Handles /boot partition."""
 
-    if os.path.isdir("/.tmp.boot"):
-        if is_bind_mnt("/.tmp.boot", "/boot"):
-            subprocess.run(["umount", "-l", "/boot"])
-        subprocess.run(["rm", "-rf", "/.tmp.boot"])
-
     subprocess.run(["cp", "-ax", os.path.join(str(new_rootfs), "boot"), "/.tmp.boot"])
-    subprocess.run(["mount", "--bind", "/.tmp.boot", "/boot"])
 
     if boot_config["type"] == "bios":
         if boot_config["loader"] == "grub":
@@ -173,6 +154,7 @@ def handle_boot(new_rootfs, boot_config) -> None:
                     [
                         "grub-install",
                         f"--directory={os.path.join(str(new_rootfs), 'usr/lib/grub/i386-pc')}",
+                        "--boot-directory=/.tmp.boot",
                         "--target=i386-pc",
                         boot_config["device"],
                     ]
@@ -180,7 +162,6 @@ def handle_boot(new_rootfs, boot_config) -> None:
                 != 0
             ):
                 output.error("aborting update...")
-                subprocess.run(["umount", "-l", "/boot"])
                 subprocess.run(["rm", "-rf", "/.tmp.boot"])
                 output.error("failed to install GRUB")
                 exit(1)
@@ -196,7 +177,8 @@ def handle_boot(new_rootfs, boot_config) -> None:
                     [
                         "grub-install",
                         f"--directory={os.path.join(str(new_rootfs), 'usr/lib/grub/x86_64-efi')}",
-                        "--efi-directory=/boot",
+                        "--efi-directory=/.tmp.boot",
+                        "--boot-directory=/.tmp.boot",
                         "--target=x86_64-efi",
                         "--removable",
                         "--bootloader-id=blendOS",
@@ -205,12 +187,10 @@ def handle_boot(new_rootfs, boot_config) -> None:
                 != 0
             ):
                 output.error("aborting update...")
-                subprocess.run(["umount", "-l", "/boot"])
                 subprocess.run(["rm", "-rf", "/.tmp.boot"])
                 output.error("failed to install GRUB")
                 exit(1)
         else:
-            subprocess.run(["umount", "-l", "/boot"])
             subprocess.run(["rm", "-rf", "/.tmp.boot"])
             output.error("unsupported bootloader for BIOS configuration")
             exit(1)
@@ -221,15 +201,14 @@ def handle_boot(new_rootfs, boot_config) -> None:
         exit(1)
 
     if boot_config["loader"] == "grub":
-        new_rootfs.exec(["grub-mkconfig", "-o", "/grub.cfg"])
+        new_rootfs.exec_chroot(["grub-mkconfig", "-o", "/grub.cfg"])
-        subprocess.run(["cp", f"{new_rootfs}/grub.cfg", "/boot/grub/grub.cfg"])
+        subprocess.run(["cp", f"{new_rootfs}/grub.cfg", "/.tmp.boot/grub/grub.cfg"])
-
-    subprocess.run(["umount", "-l", "/boot"])
 
     # Replace /boot with /.tmp.boot
     # FIXME: should be atomic
     for tmp_boot, dirs, files in os.walk("/.tmp.boot"):
         boot = tmp_boot.replace("/tmp.boot", "/boot", 1)
+        subprocess.run(["mkdir", "-p", boot])
         for path in dirs + files:
             subprocess.run(["rm", "-rf", "--", os.path.join(boot, path)])
             subprocess.run(