diff options
Diffstat (limited to 'arch/powerpc/kernel/entry_32.S')
| -rw-r--r-- | arch/powerpc/kernel/entry_32.S | 127 |
1 files changed, 89 insertions, 38 deletions
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 3e57a00b8cb..22b45a4955c 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -89,6 +89,10 @@ crit_transfer_to_handler: mfspr r0,SPRN_SRR1 stw r0,_SRR1(r11) + /* set the stack limit to the current stack + * and set the limit to protect the thread_info + * struct + */ mfspr r8,SPRN_SPRG_THREAD lwz r0,KSP_LIMIT(r8) stw r0,SAVED_KSP_LIMIT(r11) @@ -109,6 +113,10 @@ crit_transfer_to_handler: mfspr r0,SPRN_SRR1 stw r0,crit_srr1@l(0) + /* set the stack limit to the current stack + * and set the limit to protect the thread_info + * struct + */ mfspr r8,SPRN_SPRG_THREAD lwz r0,KSP_LIMIT(r8) stw r0,saved_ksp_limit@l(0) @@ -158,7 +166,7 @@ transfer_to_handler: tophys(r11,r11) addi r11,r11,global_dbcr0@l #ifdef CONFIG_SMP - rlwinm r9,r1,0,0,(31-THREAD_SHIFT) + CURRENT_THREAD_INFO(r9, r1) lwz r9,TI_CPU(r9) slwi r9,r9,3 add r11,r11,r9 @@ -179,7 +187,7 @@ transfer_to_handler: ble- stack_ovf /* then the kernel stack overflowed */ 5: #if defined(CONFIG_6xx) || defined(CONFIG_E500) - rlwinm r9,r1,0,0,31-THREAD_SHIFT + CURRENT_THREAD_INFO(r9, r1) tophys(r9,r9) /* check local flags */ lwz r12,TI_LOCAL_FLAGS(r9) mtcrf 0x01,r12 @@ -206,40 +214,37 @@ reenable_mmu: /* re-enable mmu so we can */ andi. r10,r10,MSR_EE /* Did EE change? */ beq 1f - /* Save handler and return address into the 2 unused words - * of the STACK_FRAME_OVERHEAD (sneak sneak sneak). Everything - * else can be recovered from the pt_regs except r3 which for - * normal interrupts has been set to pt_regs and for syscalls - * is an argument, so we temporarily use ORIG_GPR3 to save it - */ - stw r9,8(r1) - stw r11,12(r1) - stw r3,ORIG_GPR3(r1) /* * The trace_hardirqs_off will use CALLER_ADDR0 and CALLER_ADDR1. * If from user mode there is only one stack frame on the stack, and * accessing CALLER_ADDR1 will cause oops. So we need create a dummy * stack frame to make trace_hardirqs_off happy. + * + * This is handy because we also need to save a bunch of GPRs, + * r3 can be different from GPR3(r1) at this point, r9 and r11 + * contains the old MSR and handler address respectively, + * r4 & r5 can contain page fault arguments that need to be passed + * along as well. r12, CCR, CTR, XER etc... are left clobbered as + * they aren't useful past this point (aren't syscall arguments), + * the rest is restored from the exception frame. */ - andi. r12,r12,MSR_PR - beq 11f - stwu r1,-16(r1) - bl trace_hardirqs_off - addi r1,r1,16 - b 12f - -11: + stwu r1,-32(r1) + stw r9,8(r1) + stw r11,12(r1) + stw r3,16(r1) + stw r4,20(r1) + stw r5,24(r1) bl trace_hardirqs_off -12: + lwz r5,24(r1) + lwz r4,20(r1) + lwz r3,16(r1) + lwz r11,12(r1) + lwz r9,8(r1) + addi r1,r1,32 lwz r0,GPR0(r1) - lwz r3,ORIG_GPR3(r1) - lwz r4,GPR4(r1) - lwz r5,GPR5(r1) lwz r6,GPR6(r1) lwz r7,GPR7(r1) lwz r8,GPR8(r1) - lwz r9,8(r1) - lwz r11,12(r1) 1: mtctr r11 mtlr r9 bctr /* jump to handler */ @@ -330,7 +335,7 @@ _GLOBAL(DoSyscall) mtmsr r11 1: #endif /* CONFIG_TRACE_IRQFLAGS */ - rlwinm r10,r1,0,0,(31-THREAD_SHIFT) /* current_thread_info() */ + CURRENT_THREAD_INFO(r10, r1) lwz r11,TI_FLAGS(r10) andi. r11,r11,_TIF_SYSCALL_T_OR_A bne- syscall_dotrace @@ -351,7 +356,7 @@ ret_from_syscall: bl do_show_syscall_exit #endif mr r6,r3 - rlwinm r12,r1,0,0,(31-THREAD_SHIFT) /* current_thread_info() */ + CURRENT_THREAD_INFO(r12, r1) /* disable interrupts so current_thread_info()->flags can't change */ LOAD_MSR_KERNEL(r10,MSR_KERNEL) /* doesn't include MSR_EE */ /* Note: We don't bother telling lockdep about it */ @@ -430,6 +435,17 @@ ret_from_fork: li r3,0 b ret_from_syscall + .globl ret_from_kernel_thread +ret_from_kernel_thread: + REST_NVGPRS(r1) + bl schedule_tail + mtlr r14 + mr r3,r15 + PPC440EP_ERR42 + blrl + li r3,0 + b ret_from_syscall + /* Traced system call support */ syscall_dotrace: SAVE_NVGPRS(r1) @@ -812,7 +828,7 @@ ret_from_except: user_exc_return: /* r10 contains MSR_KERNEL here */ /* Check current_thread_info()->flags */ - rlwinm r9,r1,0,0,(31-THREAD_SHIFT) + CURRENT_THREAD_INFO(r9, r1) lwz r9,TI_FLAGS(r9) andi. r0,r9,_TIF_USER_WORK_MASK bne do_work @@ -826,19 +842,56 @@ restore_user: bnel- load_dbcr0 #endif -#ifdef CONFIG_PREEMPT b restore /* N.B. the only way to get here is from the beq following ret_from_except. */ resume_kernel: + /* check current_thread_info, _TIF_EMULATE_STACK_STORE */ + CURRENT_THREAD_INFO(r9, r1) + lwz r8,TI_FLAGS(r9) + andis. r0,r8,_TIF_EMULATE_STACK_STORE@h + beq+ 1f + + addi r8,r1,INT_FRAME_SIZE /* Get the kprobed function entry */ + + lwz r3,GPR1(r1) + subi r3,r3,INT_FRAME_SIZE /* dst: Allocate a trampoline exception frame */ + mr r4,r1 /* src: current exception frame */ + mr r1,r3 /* Reroute the trampoline frame to r1 */ + + /* Copy from the original to the trampoline. */ + li r5,INT_FRAME_SIZE/4 /* size: INT_FRAME_SIZE */ + li r6,0 /* start offset: 0 */ + mtctr r5 +2: lwzx r0,r6,r4 + stwx r0,r6,r3 + addi r6,r6,4 + bdnz 2b + + /* Do real store operation to complete stwu */ + lwz r5,GPR1(r1) + stw r8,0(r5) + + /* Clear _TIF_EMULATE_STACK_STORE flag */ + lis r11,_TIF_EMULATE_STACK_STORE@h + addi r5,r9,TI_FLAGS +0: lwarx r8,0,r5 + andc r8,r8,r11 +#ifdef CONFIG_IBM405_ERR77 + dcbt 0,r5 +#endif + stwcx. r8,0,r5 + bne- 0b +1: + +#ifdef CONFIG_PREEMPT /* check current_thread_info->preempt_count */ - rlwinm r9,r1,0,0,(31-THREAD_SHIFT) lwz r0,TI_PREEMPT(r9) cmpwi 0,r0,0 /* if non-zero, just restore regs and return */ bne restore - lwz r0,TI_FLAGS(r9) - andi. r0,r0,_TIF_NEED_RESCHED + andi. r8,r8,_TIF_NEED_RESCHED beq+ restore + lwz r3,_MSR(r1) andi. r0,r3,MSR_EE /* interrupts off? */ beq restore /* don't schedule if so */ #ifdef CONFIG_TRACE_IRQFLAGS @@ -849,7 +902,7 @@ resume_kernel: bl trace_hardirqs_off #endif 1: bl preempt_schedule_irq - rlwinm r9,r1,0,0,(31-THREAD_SHIFT) + CURRENT_THREAD_INFO(r9, r1) lwz r3,TI_FLAGS(r9) andi. r0,r3,_TIF_NEED_RESCHED bne- 1b @@ -859,8 +912,6 @@ resume_kernel: */ bl trace_hardirqs_on #endif -#else -resume_kernel: #endif /* CONFIG_PREEMPT */ /* interrupts are hard-disabled at this point */ @@ -1119,7 +1170,7 @@ ret_from_debug_exc: lwz r10,SAVED_KSP_LIMIT(r1) stw r10,KSP_LIMIT(r9) lwz r9,THREAD_INFO-THREAD(r9) - rlwinm r10,r1,0,0,(31-THREAD_SHIFT) + CURRENT_THREAD_INFO(r10, r1) lwz r10,TI_PREEMPT(r10) stw r10,TI_PREEMPT(r9) RESTORE_xSRR(SRR0,SRR1); @@ -1153,7 +1204,7 @@ load_dbcr0: lis r11,global_dbcr0@ha addi r11,r11,global_dbcr0@l #ifdef CONFIG_SMP - rlwinm r9,r1,0,0,(31-THREAD_SHIFT) + CURRENT_THREAD_INFO(r9, r1) lwz r9,TI_CPU(r9) slwi r9,r9,3 add r11,r11,r9 @@ -1194,7 +1245,7 @@ recheck: LOAD_MSR_KERNEL(r10,MSR_KERNEL) SYNC MTMSRD(r10) /* disable interrupts */ - rlwinm r9,r1,0,0,(31-THREAD_SHIFT) + CURRENT_THREAD_INFO(r9, r1) lwz r9,TI_FLAGS(r9) andi. r0,r9,_TIF_NEED_RESCHED bne- do_resched |