Commit 7b65c810 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'for-6.9-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux 

Pull btrfs fix from David Sterba:
 "Fix a problem found in 6.7 after adding the temp-fsid feature which
  changed device tracking in memory and broke grub-probe. This is used
  on initrd-less systems. There were several iterations of the fix and
  it took longer than expected"

* tag 'for-6.9-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: do not skip re-registration for the mounted device
parents 1b3e2513 d565fffa

fs/btrfs/volumes.c

+47 −11
Original line number Diff line number Diff line
@@ -1303,6 +1303,47 @@ int btrfs_forget_devices(dev_t devt) 
	return ret;

}



static bool btrfs_skip_registration(struct btrfs_super_block *disk_super,

				    const char *path, dev_t devt,

				    bool mount_arg_dev)

{

	struct btrfs_fs_devices *fs_devices;



	/*

	 * Do not skip device registration for mounted devices with matching

	 * maj:min but different paths. Booting without initrd relies on

	 * /dev/root initially, later replaced with the actual root device.

	 * A successful scan ensures grub2-probe selects the correct device.

	 */

	list_for_each_entry(fs_devices, &fs_uuids, fs_list) {

		struct btrfs_device *device;



		mutex_lock(&fs_devices->device_list_mutex);



		if (!fs_devices->opened) {

			mutex_unlock(&fs_devices->device_list_mutex);

			continue;

		}



		list_for_each_entry(device, &fs_devices->devices, dev_list) {

			if (device->bdev && (device->bdev->bd_dev == devt) &&

			    strcmp(device->name->str, path) != 0) {

				mutex_unlock(&fs_devices->device_list_mutex);



				/* Do not skip registration. */

				return false;

			}

		}

		mutex_unlock(&fs_devices->device_list_mutex);

	}



	if (!mount_arg_dev && btrfs_super_num_devices(disk_super) == 1 &&

	    !(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING))

		return true;



	return false;

}



/*

 * Look for a btrfs signature on a device. This may be called out of the mount path

 * and we are not allowed to call set_blocksize during the scan. The superblock
@@ -1320,6 +1361,7 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags, 
	struct btrfs_device *device = NULL;

	struct file *bdev_file;

	u64 bytenr, bytenr_orig;

	dev_t devt;

	int ret;



	lockdep_assert_held(&uuid_mutex);
@@ -1359,19 +1401,13 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags, 
		goto error_bdev_put;

	}



	if (!mount_arg_dev && btrfs_super_num_devices(disk_super) == 1 &&

	    !(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING)) {

		dev_t devt;

	devt = file_bdev(bdev_file)->bd_dev;

	if (btrfs_skip_registration(disk_super, path, devt, mount_arg_dev)) {

		pr_debug("BTRFS: skip registering single non-seed device %s (%d:%d)\n",

			  path, MAJOR(devt), MINOR(devt));



		ret = lookup_bdev(path, &devt);

		if (ret)

			btrfs_warn(NULL, "lookup bdev failed for path %s: %d",

				   path, ret);

		else

		btrfs_free_stale_devices(devt, NULL);



	pr_debug("BTRFS: skip registering single non-seed device %s (%d:%d)\n",

			path, MAJOR(devt), MINOR(devt));

		device = NULL;

		goto free_disk_super;

	}