On Wed, Dec 04, 2019 at 05:17:10PM +0900, Naohiro Aota wrote: > HMZONED mode cannot be used together with the RAID5/6 profile for now. > Introduce the function btrfs_check_hmzoned_mode() to check this. This > function will also check if HMZONED flag is enabled on the file system and > if the file system consists of zoned devices with equal zone size. I have a question, you wrote you check for a file system consisting of zoned devices with equal zone size. What happens if you create a multi device file system combining zoned and regular devices? Is this even supported and if no where are the checks for it? [...] > +int btrfs_check_hmzoned_mode(struct btrfs_fs_info *fs_info) > +{ > + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; > + struct btrfs_device *device; > + u64 hmzoned_devices = 0; > + u64 nr_devices = 0; > + u64 zone_size = 0; > + int incompat_hmzoned = btrfs_fs_incompat(fs_info, HMZONED); > + int ret = 0; > + > + /* Count zoned devices */ > + list_for_each_entry(device, &fs_devices->devices, dev_list) { > + if (!device->bdev) > + continue; Nit: enum blk_zoned_model zone_model = blk_zoned_model(device->bdev); if (zone_model == BLK_ZONED_HM || zone_model == BLK_ZONED_HA && incompat_hmzoned) { > + if (bdev_zoned_model(device->bdev) == BLK_ZONED_HM || > + (bdev_zoned_model(device->bdev) == BLK_ZONED_HA && > + incompat_hmzoned)) { > + hmzoned_devices++; > + if (!zone_size) { > + zone_size = device->zone_info->zone_size; > + } else if (device->zone_info->zone_size != zone_size) { > + btrfs_err(fs_info, > + "Zoned block devices must have equal zone sizes"); > + ret = -EINVAL; > + goto out; > + } > + } > + nr_devices++; > + }