powerpc/mm: Rework mm_fault_error() (b5c8f0fd) · Commits · 戴 / test

arch/powerpc/mm/fault.c

+28 −38

Original line number	Diff line number	Diff line
		@@ -147,10 +147,6 @@ static noinline int bad_area(struct pt_regs *regs, unsigned long address)
		return __bad_area(regs, address, SEGV_MAPERR);
		}

		#define MM_FAULT_RETURN 0
		#define MM_FAULT_CONTINUE -1
		#define MM_FAULT_ERR(sig) (sig)

		static int do_sigbus(struct pt_regs *regs, unsigned long address,
		unsigned int fault)
		{
		@@ -158,7 +154,7 @@ static int do_sigbus(struct pt_regs *regs, unsigned long address,
		unsigned int lsb = 0;

		if (!user_mode(regs))
		return MM_FAULT_ERR(SIGBUS);
		return SIGBUS;

		current->thread.trap_nr = BUS_ADRERR;
		info.si_signo = SIGBUS;
		@@ -179,25 +175,17 @@ static int do_sigbus(struct pt_regs *regs, unsigned long address,
		#endif
		info.si_addr_lsb = lsb;
		force_sig_info(SIGBUS, &info, current);
		return MM_FAULT_RETURN;
		return 0;
		}

		static int mm_fault_error(struct pt_regs *regs, unsigned long addr, int fault)
		{
		/*
		* Pagefault was interrupted by SIGKILL. We have no reason to
		* continue the pagefault.
		* Kernel page fault interrupted by SIGKILL. We have no reason to
		* continue processing.
		*/
		if (fatal_signal_pending(current)) {
		/* Coming from kernel, we need to deal with uaccess fixups */
		if (user_mode(regs))
		return MM_FAULT_RETURN;
		return MM_FAULT_ERR(SIGKILL);
		}

		/* No fault: be happy */
		if (!(fault & VM_FAULT_ERROR))
		return MM_FAULT_CONTINUE;
		if (fatal_signal_pending(current) && !user_mode(regs))
		return SIGKILL;

		/* Out of memory */
		if (fault & VM_FAULT_OOM) {
		@@ -206,17 +194,18 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr, int fault)
		* made us unable to handle the page fault gracefully.
		*/
		if (!user_mode(regs))
		return MM_FAULT_ERR(SIGKILL);
		return SIGSEGV;
		pagefault_out_of_memory();
		return MM_FAULT_RETURN;
		}

		if (fault & (VM_FAULT_SIGBUS\|VM_FAULT_HWPOISON\|VM_FAULT_HWPOISON_LARGE))
		} else {
		if (fault & (VM_FAULT_SIGBUS\|VM_FAULT_HWPOISON\|
		VM_FAULT_HWPOISON_LARGE))
		return do_sigbus(regs, addr, fault);

		/* We don't understand the fault code, this is fatal */
		else if (fault & VM_FAULT_SIGSEGV)
		return bad_area_nosemaphore(regs, addr);
		else
		BUG();
		return MM_FAULT_CONTINUE;
		}
		return 0;
		}

		/* Is this a bad kernel fault ? */
		@@ -274,7 +263,7 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
		int is_user = user_mode(regs);
		int is_write = page_fault_is_write(error_code);
		int fault;
		int rc = 0, store_update_sp = 0;
		int store_update_sp = 0;

		#ifdef CONFIG_PPC_ICSWX
		/*
		@@ -283,7 +272,7 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
		* look at it
		*/
		if (error_code & ICSWX_DSI_UCT) {
		rc = acop_handle_fault(regs, address, error_code);
		int rc = acop_handle_fault(regs, address, error_code);
		if (rc)
		return rc;
		}
		@@ -492,18 +481,19 @@ good_area:
		if (!fatal_signal_pending(current))
		goto retry;
		}
		/* We will enter mm_fault_error() below */
		} else
		up_read(&current->mm->mmap_sem);

		if (unlikely(fault & (VM_FAULT_RETRY\|VM_FAULT_ERROR))) {
		if (fault & VM_FAULT_SIGSEGV)
		return bad_area_nosemaphore(regs, address);
		rc = mm_fault_error(regs, address, fault);
		if (rc >= MM_FAULT_RETURN)
		return rc;
		/*
		* User mode? Just return to handle the fatal exception otherwise
		* return to bad_page_fault
		*/
		return is_user ? 0 : SIGBUS;
		}

		up_read(&current->mm->mmap_sem);

		if (unlikely(fault & VM_FAULT_ERROR))
		return mm_fault_error(regs, address, fault);

		/*
		* Major/minor page fault accounting.
		*/

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