[rfc,-next,03/10] arm64: mm: use try_vma_locked_page_fault()

Commit Message

Kefeng Wang July 13, 2023, 9:53 a.m. UTC

Use new try_vma_locked_page_fault() helper to simplify code.
No functional change intended.

Signed-off-by: Kefeng Wang <[e-mail]>
---
 arch/arm64/mm/fault.c | 28 +++++-----------------------
 1 file changed, 5 insertions(+), 23 deletions(-)

Patch

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index b8c80f7b8a5f..614bb53fc1bc 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -537,6 +537,7 @@  static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
 	unsigned int mm_flags = FAULT_FLAG_DEFAULT;
 	unsigned long addr = untagged_addr(far);
 	struct vm_area_struct *vma;
+	struct vm_locked_fault vmlf;
 
 	if (kprobe_page_fault(regs, esr))
 		return 0;
@@ -587,27 +588,11 @@  static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
 
 	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr);
 
-#ifdef CONFIG_PER_VMA_LOCK
-	if (!(mm_flags & FAULT_FLAG_USER))
-		goto lock_mmap;
-
-	vma = lock_vma_under_rcu(mm, addr);
-	if (!vma)
-		goto lock_mmap;
-
-	if (!(vma->vm_flags & vm_flags)) {
-		vma_end_read(vma);
-		goto lock_mmap;
-	}
-	fault = handle_mm_fault(vma, addr, mm_flags | FAULT_FLAG_VMA_LOCK, regs);
-	if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED)))
-		vma_end_read(vma);
-
-	if (!(fault & VM_FAULT_RETRY)) {
-		count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
+	VM_LOCKED_FAULT_INIT(vmlf, mm, addr, mm_flags, vm_flags, regs, esr);
+	if (try_vma_locked_page_fault(&vmlf, &fault))
+		goto retry;
+	else if (!(fault | VM_FAULT_RETRY))
 		goto done;
-	}
-	count_vm_vma_lock_event(VMA_LOCK_RETRY);
 
 	/* Quick path to respond to signals */
 	if (fault_signal_pending(fault, regs)) {
@@ -615,9 +600,6 @@  static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
 			goto no_context;
 		return 0;
 	}
-lock_mmap:
-#endif /* CONFIG_PER_VMA_LOCK */
-
 retry:
 	vma = lock_mm_and_find_vma(mm, addr, regs);
 	if (unlikely(!vma)) {