installer: Add code to proper unmount the BTRFS layout

[ipfire-2.x.git] / src / installer / hw.c

diff --git a/src/installer/hw.c b/src/installer/hw.c
index 5665cb9552d1c9e39fd5afacd9de74f1b3683f4e..3b26920d1b94e5f30ce083bd90afd01be9d65b76 100644 (file)
--- a/src/installer/hw.c
+++ b/src/installer/hw.c
@@ -1123,13 +1123,83 @@ int hw_umount_filesystems(struct hw_destination* dest, const char* prefix) {
                return -1;
 
        // root
-       r = hw_umount(prefix, NULL);
+       if(dest->filesystem == HW_FS_BTRFS) {
+               r = hw_umount_btrfs_layout();
+       } else {
+               r = hw_umount(prefix, NULL);
+       }
+
        if (r)
                return -1;
 
        return 0;
 }
 
+int hw_umount_btrfs_layout() {
+       const struct btrfs_subvolumes* subvolume = NULL;
+       char path[STRING_SIZE];
+       int counter = 0;
+       int retry = 1;
+       int r;
+
+       do {
+               // Reset the retry marker
+               retry = 0;
+
+               // Loop through the list of subvolumes
+               for (subvolume = btrfs_subvolumes; subvolume->name; subvolume++) {
+                       // Abort if the subvolume path could not be assigned.
+                       r = snprintf(path, sizeof(path), "%s%s", DESTINATION_MOUNT_PATH, subvolume->mount_path);
+
+                       if (r < 0) {
+                               return r;
+                       }
+
+                       // Try to umount the subvolume.
+                       r = umount2(path, 0);
+
+                       // Handle return codes.
+                       if (r) {
+                               switch(errno) {
+                                       case EBUSY:
+                                               // Set marker to retry the umount.
+                                               retry = 1;
+
+                                               // Ignore if the subvolume could not be unmounted yet,
+                                               // because it is still used.
+                                               continue;
+
+                                       case EINVAL:
+                                               // Ignore if the subvolume already has been unmounted
+                                               continue;
+                                       case ENOENT:
+                                               // Ignore if the directory does not longer exist.
+                                               continue;
+                                       default:
+                                               fprintf(flog, "Could not umount %s from %s - Error: %d\n", subvolume->name, path, r);
+                                               return r;
+                               }
+                       }
+
+                       // Print log message
+                       fprintf(flog, "Umounted %s from %s\n", subvolume->name, path);
+               }
+
+               // Abort loop if all mountpoins got umounted
+               if (retry == 0) {
+                       return 0;
+               }
+
+               // Abort after five failed umount attempts
+               if (counter == 5) {
+                       return -1;
+               }
+
+               // Increment counter.
+               counter++;
+       } while (1);
+}
+
 int hw_destroy_raid_superblocks(const struct hw_destination* dest, const char* output) {
        char cmd[STRING_SIZE];