From caed89dab0ca0e73d7e016c04e1f5957650f4ec3 Mon Sep 17 00:00:00 2001 From: Wang Kefeng Date: Wed, 22 Sep 2021 14:56:27 +0100 Subject: [PATCH] ARM: 9128/1: mm: Refactor the __do_page_fault() Clean up the multiple goto statements and drops local variable vm_fault_t fault, which will make the __do_page_fault() much more readability. No functional change. Signed-off-by: Kefeng Wang Signed-off-by: Russell King (Oracle) --- arch/arm/mm/fault.c | 34 +++++++++++++--------------------- 1 file changed, 13 insertions(+), 21 deletions(-) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index efa4020..662ac3c 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -205,35 +205,27 @@ __do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, unsigned int flags, struct task_struct *tsk, struct pt_regs *regs) { - struct vm_area_struct *vma; - vm_fault_t fault; - - vma = find_vma(mm, addr); - fault = VM_FAULT_BADMAP; + struct vm_area_struct *vma = find_vma(mm, addr); if (unlikely(!vma)) - goto out; - if (unlikely(vma->vm_start > addr)) - goto check_stack; + return VM_FAULT_BADMAP; + + if (unlikely(vma->vm_start > addr)) { + if (!(vma->vm_flags & VM_GROWSDOWN)) + return VM_FAULT_BADMAP; + if (addr < FIRST_USER_ADDRESS) + return VM_FAULT_BADMAP; + if (expand_stack(vma, addr)) + return VM_FAULT_BADMAP; + } /* * Ok, we have a good vm_area for this * memory access, so we can handle it. */ -good_area: - if (access_error(fsr, vma)) { - fault = VM_FAULT_BADACCESS; - goto out; - } + if (access_error(fsr, vma)) + return VM_FAULT_BADACCESS; return handle_mm_fault(vma, addr & PAGE_MASK, flags, regs); - -check_stack: - /* Don't allow expansion below FIRST_USER_ADDRESS */ - if (vma->vm_flags & VM_GROWSDOWN && - addr >= FIRST_USER_ADDRESS && !expand_stack(vma, addr)) - goto good_area; -out: - return fault; } static int __kprobes -- 2.7.4