Unverified Commit afb8c6fe authored by Pekka Enberg's avatar Pekka Enberg Committed by Palmer Dabbelt
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riscv/mm/fault: Move access error check to function 



Move the access error check into a access_error() function to simplify
the control flow in do_page_fault().

Signed-off-by: default avatarPekka Enberg <penberg@kernel.org>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent 67474301

arch/riscv/mm/fault.c

+27 −21
Original line number Diff line number Diff line
@@ -156,6 +156,30 @@ static void inline vmalloc_fault(struct pt_regs *regs, int code, unsigned long a 
	local_flush_tlb_page(addr);

}



static inline bool access_error(unsigned long cause, struct vm_area_struct *vma)

{

	switch (cause) {

	case EXC_INST_PAGE_FAULT:

		if (!(vma->vm_flags & VM_EXEC)) {

			return true;

		}

		break;

	case EXC_LOAD_PAGE_FAULT:

		if (!(vma->vm_flags & VM_READ)) {

			return true;

		}

		break;

	case EXC_STORE_PAGE_FAULT:

		if (!(vma->vm_flags & VM_WRITE)) {

			return true;

		}

		break;

	default:

		panic("%s: unhandled cause %lu", __func__, cause);

	}

	return false;

}



/*

 * This routine handles page faults.  It determines the address and the

 * problem, and then passes it off to one of the appropriate routines.
@@ -236,28 +260,10 @@ asmlinkage void do_page_fault(struct pt_regs *regs) 
good_area:

	code = SEGV_ACCERR;



	switch (cause) {

	case EXC_INST_PAGE_FAULT:

		if (!(vma->vm_flags & VM_EXEC)) {

			bad_area(regs, mm, code, addr);

			return;

		}

		break;

	case EXC_LOAD_PAGE_FAULT:

		if (!(vma->vm_flags & VM_READ)) {

	if (unlikely(access_error(cause, vma))) {

		bad_area(regs, mm, code, addr);

		return;

	}

		break;

	case EXC_STORE_PAGE_FAULT:

		if (!(vma->vm_flags & VM_WRITE)) {

			bad_area(regs, mm, code, addr);

			return;

		}

		break;

	default:

		panic("%s: unhandled cause %lu", __func__, cause);

	}



	/*

	 * If for any reason at all we could not handle the fault,