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

Signed-off-by: Kefeng Wang <wangkefeng.w...@huawei.com>
---
 arch/x86/mm/fault.c | 55 +++++++++++++++++++--------------------------
 1 file changed, 23 insertions(+), 32 deletions(-)

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index ab778eac1952..3edc9edc0b28 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1227,6 +1227,13 @@ do_kern_addr_fault(struct pt_regs *regs, unsigned long 
hw_error_code,
 }
 NOKPROBE_SYMBOL(do_kern_addr_fault);
 
+#ifdef CONFIG_PER_VMA_LOCK
+bool arch_vma_access_error(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+       return access_error(vmf->fault_code, vma);
+}
+#endif
+
 /*
  * Handle faults in the user portion of the address space.  Nothing in here
  * should check X86_PF_USER without a specific justification: for almost
@@ -1241,13 +1248,13 @@ void do_user_addr_fault(struct pt_regs *regs,
                        unsigned long address)
 {
        struct vm_area_struct *vma;
-       struct task_struct *tsk;
-       struct mm_struct *mm;
+       struct mm_struct *mm = current->mm;
        vm_fault_t fault;
-       unsigned int flags = FAULT_FLAG_DEFAULT;
-
-       tsk = current;
-       mm = tsk->mm;
+       struct vm_fault vmf = {
+               .real_address = address,
+               .fault_code = error_code,
+               .flags = FAULT_FLAG_DEFAULT
+       };
 
        if (unlikely((error_code & (X86_PF_USER | X86_PF_INSTR)) == 
X86_PF_INSTR)) {
                /*
@@ -1311,7 +1318,7 @@ void do_user_addr_fault(struct pt_regs *regs,
         */
        if (user_mode(regs)) {
                local_irq_enable();
-               flags |= FAULT_FLAG_USER;
+               vmf.flags |= FAULT_FLAG_USER;
        } else {
                if (regs->flags & X86_EFLAGS_IF)
                        local_irq_enable();
@@ -1326,11 +1333,11 @@ void do_user_addr_fault(struct pt_regs *regs,
         * maybe_mkwrite() can create a proper shadow stack PTE.
         */
        if (error_code & X86_PF_SHSTK)
-               flags |= FAULT_FLAG_WRITE;
+               vmf.flags |= FAULT_FLAG_WRITE;
        if (error_code & X86_PF_WRITE)
-               flags |= FAULT_FLAG_WRITE;
+               vmf.flags |= FAULT_FLAG_WRITE;
        if (error_code & X86_PF_INSTR)
-               flags |= FAULT_FLAG_INSTRUCTION;
+               vmf.flags |= FAULT_FLAG_INSTRUCTION;
 
 #ifdef CONFIG_X86_64
        /*
@@ -1350,26 +1357,11 @@ void do_user_addr_fault(struct pt_regs *regs,
        }
 #endif
 
-       if (!(flags & FAULT_FLAG_USER))
-               goto lock_mmap;
-
-       vma = lock_vma_under_rcu(mm, address);
-       if (!vma)
-               goto lock_mmap;
-
-       if (unlikely(access_error(error_code, vma))) {
-               vma_end_read(vma);
-               goto lock_mmap;
-       }
-       fault = handle_mm_fault(vma, address, 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);
+       fault = try_vma_locked_page_fault(&vmf);
+       if (fault == VM_FAULT_NONE)
+               goto retry;
+       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)) {
@@ -1379,7 +1371,6 @@ void do_user_addr_fault(struct pt_regs *regs,
                                                 ARCH_DEFAULT_PKEY);
                return;
        }
-lock_mmap:
 
 retry:
        vma = lock_mm_and_find_vma(mm, address, regs);
@@ -1410,7 +1401,7 @@ void do_user_addr_fault(struct pt_regs *regs,
         * userland). The return to userland is identified whenever
         * FAULT_FLAG_USER|FAULT_FLAG_KILLABLE are both set in flags.
         */
-       fault = handle_mm_fault(vma, address, flags, regs);
+       fault = handle_mm_fault(vma, address, vmf.flags, regs);
 
        if (fault_signal_pending(fault, regs)) {
                /*
@@ -1434,7 +1425,7 @@ void do_user_addr_fault(struct pt_regs *regs,
         * that we made any progress. Handle this case first.
         */
        if (unlikely(fault & VM_FAULT_RETRY)) {
-               flags |= FAULT_FLAG_TRIED;
+               vmf.flags |= FAULT_FLAG_TRIED;
                goto retry;
        }
 
-- 
2.27.0

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