openrisc: fix up vmalloc page table loading

vmalloc'ed pages are faulted into a process' page tables on demand.  In
order to facilitate this, do_page_fault needs to know whether it was
called via a page fault exception or a TLB-miss exception.

This patch adds a wrapper around the _x_page_fault_handler entry points
that the TLB-miss exceptions can call into in order to have the relevant
parameter set to satisfy do_page_fault.

This fixes a bug and is "good enough" for now.  That said, this whole
handling of vmalloc needs to be audited for correctness at some point.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
This commit is contained in:
Jonas Bonn 2013-02-14 16:16:49 +01:00
parent 7f81ea7e28
commit a81252d75e
2 changed files with 14 additions and 6 deletions

View File

@ -201,12 +201,17 @@ EXCEPTION_ENTRY(_bus_fault_handler)
l.nop
/* ---[ 0x300: Data Page Fault exception ]------------------------------- */
EXCEPTION_ENTRY(_dtlb_miss_page_fault_handler)
l.and r5,r5,r0
l.j 1f
l.nop
EXCEPTION_ENTRY(_data_page_fault_handler)
/* set up parameters for do_page_fault */
l.ori r5,r0,0x300 // exception vector
1:
l.addi r3,r1,0 // pt_regs
/* r4 set be EXCEPTION_HANDLE */ // effective address of fault
l.ori r5,r0,0x300 // exception vector
/*
* __PHX__: TODO
@ -276,12 +281,17 @@ EXCEPTION_ENTRY(_data_page_fault_handler)
l.nop
/* ---[ 0x400: Insn Page Fault exception ]------------------------------- */
EXCEPTION_ENTRY(_itlb_miss_page_fault_handler)
l.and r5,r5,r0
l.j 1f
l.nop
EXCEPTION_ENTRY(_insn_page_fault_handler)
/* set up parameters for do_page_fault */
l.ori r5,r0,0x400 // exception vector
1:
l.addi r3,r1,0 // pt_regs
/* r4 set be EXCEPTION_HANDLE */ // effective address of fault
l.ori r5,r0,0x400 // exception vector
l.ori r6,r0,0x0 // !write access
/* call fault.c handler in or32/mm/fault.c */

View File

@ -1069,8 +1069,7 @@ d_pte_not_present:
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
EXCEPTION_LOAD_GPR6
l.j _dispatch_do_dpage_fault
l.nop
EXCEPTION_HANDLE(_dtlb_miss_page_fault_handler)
/* ==============================================[ ITLB miss handler ]=== */
ENTRY(itlb_miss_handler)
@ -1192,8 +1191,7 @@ i_pte_not_present:
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
EXCEPTION_LOAD_GPR6
l.j _dispatch_do_ipage_fault
l.nop
EXCEPTION_HANDLE(_itlb_miss_page_fault_handler)
/* ==============================================[ boot tlb handlers ]=== */