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/s390/mm/fault.c | 66 ++++++++++++++++++--------------------------
1 file changed, 27 insertions(+), 39 deletions(-)
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 099c4824dd8a..fbbdebde6ea7 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -357,16 +357,18 @@ static noinline void do_fault_error(struct pt_regs *regs,
vm_fault_t fault)
static inline vm_fault_t do_exception(struct pt_regs *regs, int access)
{
struct gmap *gmap;
- struct task_struct *tsk;
- struct mm_struct *mm;
struct vm_area_struct *vma;
enum fault_type type;
- unsigned long address;
- unsigned int flags;
+ struct mm_struct *mm = current->mm;
+ unsigned long address = get_fault_address(regs);
vm_fault_t fault;
bool is_write;
+ struct vm_fault vmf = {
+ .real_address = address,
+ .flags = FAULT_FLAG_DEFAULT,
+ .vm_flags = access,
+ };
- tsk = current;
/*
* The instruction that caused the program check has
* been nullified. Don't signal single step via SIGTRAP.
@@ -376,8 +378,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs,
int access)
if (kprobe_page_fault(regs, 14))
return 0;
- mm = tsk->mm;
- address = get_fault_address(regs);
is_write = fault_is_write(regs);
/*
@@ -398,45 +398,33 @@ static inline vm_fault_t do_exception(struct pt_regs
*regs, int access)
}
perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
- flags = FAULT_FLAG_DEFAULT;
if (user_mode(regs))
- flags |= FAULT_FLAG_USER;
+ vmf.flags |= FAULT_FLAG_USER;
if (is_write)
- access = VM_WRITE;
- if (access == VM_WRITE)
- flags |= FAULT_FLAG_WRITE;
- if (!(flags & FAULT_FLAG_USER))
- goto lock_mmap;
- vma = lock_vma_under_rcu(mm, address);
- if (!vma)
- goto lock_mmap;
- if (!(vma->vm_flags & access)) {
- 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);
- if (likely(!(fault & VM_FAULT_ERROR)))
- fault = 0;
+ vmf.vm_flags = VM_WRITE;
+ if (vmf.vm_flags == VM_WRITE)
+ vmf.flags |= FAULT_FLAG_WRITE;
+
+ fault = try_vma_locked_page_fault(&vmf);
+ if (fault == VM_FAULT_NONE)
+ goto lock_mm;
+ if (!(fault & VM_FAULT_RETRY))
goto out;
- }
- count_vm_vma_lock_event(VMA_LOCK_RETRY);
+
/* Quick path to respond to signals */
if (fault_signal_pending(fault, regs)) {
fault = VM_FAULT_SIGNAL;
goto out;
}
-lock_mmap:
+
+lock_mm:
mmap_read_lock(mm);
gmap = NULL;
if (IS_ENABLED(CONFIG_PGSTE) && type == GMAP_FAULT) {
gmap = (struct gmap *) S390_lowcore.gmap;
current->thread.gmap_addr = address;
- current->thread.gmap_write_flag = !!(flags & FAULT_FLAG_WRITE);
+ current->thread.gmap_write_flag = !!(vmf.flags &
FAULT_FLAG_WRITE);
current->thread.gmap_int_code = regs->int_code & 0xffff;
address = __gmap_translate(gmap, address);
if (address == -EFAULT) {
@@ -444,7 +432,7 @@ static inline vm_fault_t do_exception(struct pt_regs *regs,
int access)
goto out_up;
}
if (gmap->pfault_enabled)
- flags |= FAULT_FLAG_RETRY_NOWAIT;
+ vmf.flags |= FAULT_FLAG_RETRY_NOWAIT;
}
retry:
@@ -466,7 +454,7 @@ static inline vm_fault_t do_exception(struct pt_regs *regs,
int access)
* we can handle it..
*/
fault = VM_FAULT_BADACCESS;
- if (unlikely(!(vma->vm_flags & access)))
+ if (unlikely(!(vma->vm_flags & vmf.vm_flags)))
goto out_up;
/*
@@ -474,10 +462,10 @@ static inline vm_fault_t do_exception(struct pt_regs
*regs, int access)
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
- fault = handle_mm_fault(vma, address, flags, regs);
+ fault = handle_mm_fault(vma, address, vmf.flags, regs);
if (fault_signal_pending(fault, regs)) {
fault = VM_FAULT_SIGNAL;
- if (flags & FAULT_FLAG_RETRY_NOWAIT)
+ if (vmf.flags & FAULT_FLAG_RETRY_NOWAIT)
goto out_up;
goto out;
}
@@ -497,7 +485,7 @@ static inline vm_fault_t do_exception(struct pt_regs *regs,
int access)
if (fault & VM_FAULT_RETRY) {
if (IS_ENABLED(CONFIG_PGSTE) && gmap &&
- (flags & FAULT_FLAG_RETRY_NOWAIT)) {
+ (vmf.flags & FAULT_FLAG_RETRY_NOWAIT)) {
/*
* FAULT_FLAG_RETRY_NOWAIT has been set, mmap_lock has
* not been released
@@ -506,8 +494,8 @@ static inline vm_fault_t do_exception(struct pt_regs *regs,
int access)
fault = VM_FAULT_PFAULT;
goto out_up;
}
- flags &= ~FAULT_FLAG_RETRY_NOWAIT;
- flags |= FAULT_FLAG_TRIED;
+ vmf.flags &= ~FAULT_FLAG_RETRY_NOWAIT;
+ vmf.flags |= FAULT_FLAG_TRIED;
mmap_read_lock(mm);
goto retry;
}
--
2.27.0
