fs/btrfs/block-rsv.c

18  *   currently reserved for this block reserve.
24  *   -> Reserve
62  *   to make our extent tree updates.  This block reserve acts as an overflow
63  *   buffer in case our delayed refs reserve does not reserve enough space to
79  *   reservation.  We use the transaction items and pre-reserve space for every
85  *   the most dynamic block reserve in the system, we will try to refill this
86  *   block reserve first with any excess returned by any other block reserve.
89  *   This is the fallback block reserve to make us try to reserve space if we
92  *   content to just reserve space from the space_info on demand.
96  *   allocate a block reserve, set it to some size, and then truncate bytes
101  *   re-reserve.
283 	 * If we are a delayed block reserve then push to the global rsv,  in btrfs_block_rsv_release()
284 	 * otherwise dump into the global delayed reserve if it is not full.  in btrfs_block_rsv_release()
364 	 * But we also want to reserve enough space so we can do the fallback  in btrfs_update_global_block_rsv()
365 	 * global reserve for an unlink, which is an additional  in btrfs_update_global_block_rsv()
512 	 * The global reserve still exists to save us from ourselves, so don't  in btrfs_use_block_rsv()
513 	 * warn_on if we are short on our delayed refs reserve.  in btrfs_use_block_rsv()
531 	 * If we couldn't reserve metadata bytes try and use some from  in btrfs_use_block_rsv()
532 	 * the global reserve if its space type is the same as the global  in btrfs_use_block_rsv()