How to use update & DLC in rpcs3?

If I write/change anything else to /dev_bdvd/: ""
I get error & can't boot any game. maybe this is game specific error.

E {PPU[0x100000d] Thread (fios mediathread 5) [0x00e9e090]} sys_fs: sys_fs_open(“/dev_bdvd/PS3_GAME/USRDIR/data.psarc”) failed: device not mounted

E {PPU[0x100000d] Thread (fios mediathread 5) [0x00e9e090]} : 'sys_fs_open' failed with 0x8001003a : CELL_ENOTMOUNTED

E {PPU[0x100000d] Thread (fios mediathread 5) [0x00e9dee4]} : 'sys_fs_stat' failed with 0x8001003a : CELL_ENOTMOUNTED