From b2373f255cacdc1ea4da25e75a5a78949ffd9d66 Mon Sep 17 00:00:00 2001 From: Anand Jain Date: Tue, 3 Jun 2014 11:36:03 +0800 Subject: [PATCH] btrfs: create sprout should rename fsid on the sysfs as well Creating sprout will change the fsid of the mounted root. do the same on the sysfs as well. reproducer: mount /dev/sdb /btrfs (seed disk) btrfs dev add /dev/sdc /btrfs mount -o rw,remount /btrfs btrfs dev del /dev/sdb /btrfs mount /dev/sdb /btrfs Error: kobject_add_internal failed for fe350492-dc28-4051-a601-e017b17e6145 with -EEXIST, don't try to register things with the same name in the same directory. Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: Chris Mason --- fs/btrfs/volumes.c | 9 +++++++++ include/uapi/linux/btrfs.h | 1 + 2 files changed, 10 insertions(+) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 19b67e969b52..6ca0d9cc46f9 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2154,6 +2154,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path) mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); if (seeding_dev) { + char fsid_buf[BTRFS_UUID_UNPARSED_SIZE]; ret = init_first_rw_device(trans, root, device); if (ret) { btrfs_abort_transaction(trans, root, ret); @@ -2164,6 +2165,14 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path) btrfs_abort_transaction(trans, root, ret); goto error_trans; } + + /* Sprouting would change fsid of the mounted root, + * so rename the fsid on the sysfs + */ + snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", + root->fs_info->fsid); + if (kobject_rename(&root->fs_info->super_kobj, fsid_buf)) + goto error_trans; } else { ret = btrfs_add_device(trans, root, device); if (ret) { diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index 6f9c38ce45c7..2f47824e7a36 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -38,6 +38,7 @@ struct btrfs_ioctl_vol_args { #define BTRFS_SUBVOL_QGROUP_INHERIT (1ULL << 2) #define BTRFS_FSID_SIZE 16 #define BTRFS_UUID_SIZE 16 +#define BTRFS_UUID_UNPARSED_SIZE 37 #define BTRFS_QGROUP_INHERIT_SET_LIMITS (1ULL << 0) -- 2.20.1