mm: simplify follow_pte{,pmd}
Merge __follow_pte_pmd, follow_pte_pmd and follow_pte into a single
follow_pte function and just pass two additional NULL arguments for the
two previous follow_pte callers.
[sfr@canb.auug.org.au: merge fix for "s390/pci: remove races against pte updates"]
Link: https://lkml.kernel.org/r/20201111221254.7f6a3658@canb.auug.org.au
Link: https://lkml.kernel.org/r/20201029101432.47011-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memory.c b/mm/memory.c
index 126e140..7d60876 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4707,9 +4707,9 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
}
#endif /* __PAGETABLE_PMD_FOLDED */
-static int __follow_pte_pmd(struct mm_struct *mm, unsigned long address,
- struct mmu_notifier_range *range,
- pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp)
+int follow_pte(struct mm_struct *mm, unsigned long address,
+ struct mmu_notifier_range *range, pte_t **ptepp, pmd_t **pmdpp,
+ spinlock_t **ptlp)
{
pgd_t *pgd;
p4d_t *p4d;
@@ -4774,31 +4774,6 @@ static int __follow_pte_pmd(struct mm_struct *mm, unsigned long address,
return -EINVAL;
}
-static inline int follow_pte(struct mm_struct *mm, unsigned long address,
- pte_t **ptepp, spinlock_t **ptlp)
-{
- int res;
-
- /* (void) is needed to make gcc happy */
- (void) __cond_lock(*ptlp,
- !(res = __follow_pte_pmd(mm, address, NULL,
- ptepp, NULL, ptlp)));
- return res;
-}
-
-int follow_pte_pmd(struct mm_struct *mm, unsigned long address,
- struct mmu_notifier_range *range,
- pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp)
-{
- int res;
-
- /* (void) is needed to make gcc happy */
- (void) __cond_lock(*ptlp,
- !(res = __follow_pte_pmd(mm, address, range,
- ptepp, pmdpp, ptlp)));
- return res;
-}
-
/**
* follow_pfn - look up PFN at a user virtual address
* @vma: memory mapping
@@ -4819,7 +4794,7 @@ int follow_pfn(struct vm_area_struct *vma, unsigned long address,
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
return ret;
- ret = follow_pte(vma->vm_mm, address, &ptep, &ptl);
+ ret = follow_pte(vma->vm_mm, address, NULL, &ptep, NULL, &ptl);
if (ret)
return ret;
*pfn = pte_pfn(*ptep);
@@ -4840,7 +4815,7 @@ int follow_phys(struct vm_area_struct *vma,
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
goto out;
- if (follow_pte(vma->vm_mm, address, &ptep, &ptl))
+ if (follow_pte(vma->vm_mm, address, NULL, &ptep, NULL, &ptl))
goto out;
pte = *ptep;