diff options
| author |   Vineet Gupta <vgupta@synopsys.com> | 2013-06-12 13:49:02 +0530 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2013-06-22 19:23:20 +0530 |
| commit | 3e1ae441886b82fbf605f37ac0756b811d55f3d5 (patch) | |
| tree | 36c7e28d41922288ae1b3a466cf851f7a64da68e /arch/arc/mm | |
| parent | ARC: [mm] Make stack/heap Non-executable by default (diff) | |
| download | linux-dev-3e1ae441886b82fbf605f37ac0756b811d55f3d5.tar.xz linux-dev-3e1ae441886b82fbf605f37ac0756b811d55f3d5.zip | |
ARC: [mm] Remove @write argument to do_page_fault()
This can be ascertained within do_page_fault() since it gets the full
ECR (Exception Cause Register).
Further, for both the callers of do_page_fault(): Prot-V / D-TLB-Miss,
the cause sub-fields in ECR are same for same type of access, making the
code much more simpler.
D-TLB-Miss [LD] 0x00_21_01_00
Prot-V [LD] 0x00_23_01_00
^^
D-TLB-Miss [ST] 0x00_21_02_00
Prot-V [ST] 0x00_23_02_00
^^
D-TLB-Miss [EX] 0x00_21_03_00
Prot-V [EX] 0x00_23_03_00
^^
This helps code consolidation, which is even better when moving code from
assembler to "C".
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc/mm')
| -rw-r--r-- | arch/arc/mm/fault.c | 3 | ||||
| -rw-r--r-- | arch/arc/mm/tlbex.S | 14 |
2 files changed, 4 insertions, 13 deletions
diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c index c0decc1f8d22..fdafeb1917cc 100644 --- a/arch/arc/mm/fault.c +++ b/arch/arc/mm/fault.c @@ -52,7 +52,7 @@ bad_area: return 1; } -void do_page_fault(struct pt_regs *regs, int write, unsigned long address, +void do_page_fault(struct pt_regs *regs, unsigned long address, unsigned long cause_code) { struct vm_area_struct *vma = NULL; @@ -60,6 +60,7 @@ void do_page_fault(struct pt_regs *regs, int write, unsigned long address, struct mm_struct *mm = tsk->mm; siginfo_t info; int fault, ret; + int write = cause_code & (1 << ECR_C_BIT_DTLB_ST_MISS); /* ST/EX */ unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE | (write ? FAULT_FLAG_WRITE : 0); diff --git a/arch/arc/mm/tlbex.S b/arch/arc/mm/tlbex.S index 7bf811d51af8..bd8bc90f61d3 100644 --- a/arch/arc/mm/tlbex.S +++ b/arch/arc/mm/tlbex.S @@ -381,18 +381,8 @@ do_slow_path_pf: ; ------- setup args for Linux Page fault Hanlder --------- mov_s r0, sp - lr r2, [efa] - lr r3, [ecr] - - ; Both st and ex imply WRITE access of some sort, hence do_page_fault( ) - ; invoked with write=1 for DTLB-st/ex Miss and write=0 for ITLB miss or - ; DTLB-ld Miss - ; DTLB Miss Cause code is ld = 0x01 , st = 0x02, ex = 0x03 - ; Following code uses that fact that st/ex have one bit in common - - btst_s r3, ECR_C_BIT_DTLB_ST_MISS - mov.z r1, 0 - mov.nz r1, 1 + lr r1, [efa] + lr r2, [ecr] ; We don't want exceptions to be disabled while the fault is handled. ; Now that we have saved the context we return from exception hence |