[PATCH rfc -next 06/10] riscv: mm: use try_vma_locked_page_fault()
Kefeng Wang
wangkefeng.wang at huawei.com
Thu Jul 13 02:53:34 PDT 2023
Use new try_vma_locked_page_fault() helper to simplify code.
No functional change intended.
Signed-off-by: Kefeng Wang <wangkefeng.wang at huawei.com>
---
arch/riscv/mm/fault.c | 38 +++++++++++++++-----------------------
1 file changed, 15 insertions(+), 23 deletions(-)
diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 6ea2cce4cc17..13bc60370b5c 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -215,6 +215,16 @@ static inline bool access_error(unsigned long cause, struct vm_area_struct *vma)
return false;
}
+#ifdef CONFIG_PER_VMA_LOCK
+int arch_vma_check_access(struct vm_area_struct *vma,
+ struct vm_locked_fault *vmlf)
+{
+ if (unlikely(access_error(vmlf->fault_code, vma)))
+ return -EINVAL;
+ return 0;
+}
+#endif
+
/*
* This routine handles page faults. It determines the address and the
* problem, and then passes it off to one of the appropriate routines.
@@ -228,6 +238,7 @@ void handle_page_fault(struct pt_regs *regs)
unsigned int flags = FAULT_FLAG_DEFAULT;
int code = SEGV_MAPERR;
vm_fault_t fault;
+ struct vm_locked_fault vmlf;
cause = regs->cause;
addr = regs->badaddr;
@@ -283,35 +294,18 @@ void handle_page_fault(struct pt_regs *regs)
flags |= FAULT_FLAG_WRITE;
else if (cause == EXC_INST_PAGE_FAULT)
flags |= FAULT_FLAG_INSTRUCTION;
-#ifdef CONFIG_PER_VMA_LOCK
- if (!(flags & FAULT_FLAG_USER))
- goto lock_mmap;
- vma = lock_vma_under_rcu(mm, addr);
- if (!vma)
- goto lock_mmap;
-
- if (unlikely(access_error(cause, vma))) {
- vma_end_read(vma);
- goto lock_mmap;
- }
-
- fault = handle_mm_fault(vma, addr, flags | FAULT_FLAG_VMA_LOCK, regs);
- vma_end_read(vma);
-
- if (!(fault & VM_FAULT_RETRY)) {
- count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
+ VM_LOCKED_FAULT_INIT(vmlf, mm, addr, flags, 0, regs, cause);
+ 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);
if (fault_signal_pending(fault, regs)) {
if (!user_mode(regs))
no_context(regs, addr);
return;
}
-lock_mmap:
-#endif /* CONFIG_PER_VMA_LOCK */
retry:
vma = lock_mm_and_find_vma(mm, addr, regs);
@@ -368,9 +362,7 @@ void handle_page_fault(struct pt_regs *regs)
mmap_read_unlock(mm);
-#ifdef CONFIG_PER_VMA_LOCK
done:
-#endif
if (unlikely(fault & VM_FAULT_ERROR)) {
tsk->thread.bad_cause = cause;
mm_fault_error(regs, addr, fault);
--
2.27.0
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