ret = 1;
device->fs_devices = fs_devices;
} else if (!device->name || strcmp(device->name->str, path)) {
+ /*
+ * When FS is already mounted.
+ * 1. If you are here and if the device->name is NULL that
+ * means this device was missing at time of FS mount.
+ * 2. If you are here and if the device->name is different
+ * from 'path' that means either
+ * a. The same device disappeared and reappeared with
+ * different name. or
+ * b. The missing-disk-which-was-replaced, has
+ * reappeared now.
+ *
+ * We must allow 1 and 2a above. But 2b would be a spurious
+ * and unintentional.
+ *
+ * Further in case of 1 and 2a above, the disk at 'path'
+ * would have missed some transaction when it was away and
+ * in case of 2a the stale bdev has to be updated as well.
+ * 2b must not be allowed at all time.
+ */
+
+ /*
+ * As of now don't allow update to btrfs_fs_device through
+ * the btrfs dev scan cli, after FS has been mounted.
+ */
+ if (fs_devices->opened) {
+ return -EBUSY;
+ } else {
+ /*
+ * That is if the FS is _not_ mounted and if you
+ * are here, that means there is more than one
+ * disk with same uuid and devid.We keep the one
+ * with larger generation number or the last-in if
+ * generation are equal.
+ */
+ if (found_transid < device->generation)
+ return -EEXIST;
+ }
+
name = rcu_string_strdup(path, GFP_NOFS);
if (!name)
return -ENOMEM;
}
}
+ /*
+ * Unmount does not free the btrfs_device struct but would zero
+ * generation along with most of the other members. So just update
+ * it back. We need it to pick the disk with largest generation
+ * (as above).
+ */
+ if (!fs_devices->opened)
+ device->generation = found_transid;
+
if (found_transid > fs_devices->latest_trans) {
fs_devices->latest_devid = devid;
fs_devices->latest_trans = found_transid;
btrfs_set_device_io_align(leaf, dev_item, device->io_align);
btrfs_set_device_io_width(leaf, dev_item, device->io_width);
btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
- btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
+ btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes);
btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
btrfs_set_device_group(leaf, dev_item, 0);
btrfs_set_device_seek_speed(leaf, dev_item, 0);
device->fs_devices->total_devices--;
if (device->missing)
- root->fs_info->fs_devices->missing_devices--;
+ device->fs_devices->missing_devices--;
next_device = list_entry(root->fs_info->fs_devices->devices.next,
struct btrfs_device, dev_list);
if (srcdev->bdev) {
fs_info->fs_devices->open_devices--;
- /* zero out the old super */
- btrfs_scratch_superblock(srcdev);
+ /*
+ * zero out the old super if it is not writable
+ * (e.g. seed device)
+ */
+ if (srcdev->writeable)
+ btrfs_scratch_superblock(srcdev);
}
call_rcu(&srcdev->rcu, free_device);
fs_devices->seeding = 0;
fs_devices->num_devices = 0;
fs_devices->open_devices = 0;
+ fs_devices->missing_devices = 0;
+ fs_devices->num_can_discard = 0;
+ fs_devices->rotating = 0;
fs_devices->seed = seed_devices;
generate_random_uuid(fs_devices->fsid);
else
generate_random_uuid(dev->uuid);
- btrfs_init_work(&dev->work, pending_bios_fn, NULL, NULL);
+ btrfs_init_work(&dev->work, btrfs_submit_helper,
+ pending_bios_fn, NULL, NULL);
return dev;
}