BCH_OPT(inodes_32bit, u8, OPT_RUNTIME, \
OPT_BOOL(), \
BCH_SB_INODE_32BIT, false) \
- BCH_OPT(gc_reserve_percent, u8, OPT_MOUNT, \
+ BCH_OPT(gc_reserve_percent, u8, OPT_RUNTIME, \
OPT_UINT(5, 21), \
BCH_SB_GC_RESERVE, 8) \
+ BCH_OPT(gc_reserve_bytes, u64, OPT_RUNTIME, \
+ OPT_UINT(0, U64_MAX), \
+ BCH_SB_GC_RESERVE_BYTES, 0) \
BCH_OPT(root_reserve_percent, u8, OPT_MOUNT, \
OPT_UINT(0, 100), \
BCH_SB_ROOT_RESERVE, 0) \