Operating Systems (CS 273 (OS), Fall 2020)

Page fault handling

Hardware trap to kernel; save some state
TO UPDATE: Save some process state; call OS (arch/i386/mm/fault.c:do_page_fault())
TO UPDATE: OS finds desired VPN (mm/swap.c)
TO UPDATE: Check validity and protection of VPN. Get free page frame (mm/page_alloc.c)
TO UPDATE: If page frame is dirty, page out (mm/page_io.c:rw_swap_page()) and block process. Reserve that page frame
TO UPDATE: Get page from disk (mm/page_io.c:rw_swap_page() or rw_swap_page_nolock()) (block the process)
Update page tables, mark page frame as being in use
Instruction backup
TO UPDATE: Schedule the process (kernel/sched.c)
Restore process state; continue execution