[PATCH v4 1/3] x86/mm/pat: Move follow_phys to pat-related file

[Wupeng Ma <mawupeng1@huawei.com>]

From: Ma Wupeng <mawupeng1@huawei.com>

Since only PAT in x86 use follow_phys(), move this to from memory.c to
memtype.c and make it static.

Since config HAVE_IOREMAP_PROT is selected by x86, drop this config macro.

Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
---
 arch/x86/mm/pat/memtype.c | 28 ++++++++++++++++++++++++++++
 include/linux/mm.h        |  2 --
 mm/memory.c               | 28 ----------------------------
 3 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
index 0904d7e8e126..d8c37aaaf041 100644
--- a/arch/x86/mm/pat/memtype.c
+++ b/arch/x86/mm/pat/memtype.c
@@ -950,6 +950,34 @@ static void free_pfn_range(u64 paddr, unsigned long size)
 		memtype_free(paddr, paddr + size);
 }
 
+static int follow_phys(struct vm_area_struct *vma,
+		unsigned long address, unsigned int flags,
+		unsigned long *prot, resource_size_t *phys)
+{
+	int ret = -EINVAL;
+	pte_t *ptep, pte;
+	spinlock_t *ptl;
+
+	if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
+		goto out;
+
+	if (follow_pte(vma->vm_mm, address, &ptep, &ptl))
+		goto out;
+	pte = ptep_get(ptep);
+
+	if ((flags & FOLL_WRITE) && !pte_write(pte))
+		goto unlock;
+
+	*prot = pgprot_val(pte_pgprot(pte));
+	*phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT;
+
+	ret = 0;
+unlock:
+	pte_unmap_unlock(ptep, ptl);
+out:
+	return ret;
+}
+
 /*
  * track_pfn_copy is called when vma that is covering the pfnmap gets
  * copied through copy_page_range().
diff --git a/include/linux/mm.h b/include/linux/mm.h
index f5a97dec5169..75c683f2f5ae 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2375,8 +2375,6 @@ int follow_pte(struct mm_struct *mm, unsigned long address,
 	       pte_t **ptepp, spinlock_t **ptlp);
 int follow_pfn(struct vm_area_struct *vma, unsigned long address,
 	unsigned long *pfn);
-int follow_phys(struct vm_area_struct *vma, unsigned long address,
-		unsigned int flags, unsigned long *prot, resource_size_t *phys);
 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
 			void *buf, int len, int write);
 
diff --git a/mm/memory.c b/mm/memory.c
index 15f8b10ea17c..86ad7f1ca3af 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -5802,34 +5802,6 @@ int follow_pfn(struct vm_area_struct *vma, unsigned long address,
 EXPORT_SYMBOL(follow_pfn);
 
 #ifdef CONFIG_HAVE_IOREMAP_PROT
-int follow_phys(struct vm_area_struct *vma,
-		unsigned long address, unsigned int flags,
-		unsigned long *prot, resource_size_t *phys)
-{
-	int ret = -EINVAL;
-	pte_t *ptep, pte;
-	spinlock_t *ptl;
-
-	if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
-		goto out;
-
-	if (follow_pte(vma->vm_mm, address, &ptep, &ptl))
-		goto out;
-	pte = ptep_get(ptep);
-
-	if ((flags & FOLL_WRITE) && !pte_write(pte))
-		goto unlock;
-
-	*prot = pgprot_val(pte_pgprot(pte));
-	*phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT;
-
-	ret = 0;
-unlock:
-	pte_unmap_unlock(ptep, ptl);
-out:
-	return ret;
-}
-
 /**
  * generic_access_phys - generic implementation for iomem mmap access
  * @vma: the vma to access
-- 
2.25.1