nfs: disintegrate UAPI for nfs

This is to complete part of the Userspace API (UAPI) disintegration for which
the preparatory patches were pulled recently.  After these patches, userspace
headers will be segregated into:

        include/uapi/linux/.../foo.h

for the userspace interface stuff, and:

        include/linux/.../foo.h

for the strictly kernel internal stuff.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 65 insertions, 50 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 57361708d1a..fb135ba4aba 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -712,7 +712,7 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
 	add_taint(TAINT_BAD_PAGE);
 }
 
-static inline int is_cow_mapping(vm_flags_t flags)
+static inline bool is_cow_mapping(vm_flags_t flags)
 {
 	return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
 }
@@ -1039,6 +1039,9 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 	unsigned long next;
 	unsigned long addr = vma->vm_start;
 	unsigned long end = vma->vm_end;
+	unsigned long mmun_start;	/* For mmu_notifiers */
+	unsigned long mmun_end;		/* For mmu_notifiers */
+	bool is_cow;
 	int ret;
 
 	/*
@@ -1047,7 +1050,8 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 	 * readonly mappings. The tradeoff is that copy_page_range is more
 	 * efficient than faulting.
 	 */
-	if (!(vma->vm_flags & (VM_HUGETLB|VM_NONLINEAR|VM_PFNMAP|VM_INSERTPAGE))) {
+	if (!(vma->vm_flags & (VM_HUGETLB | VM_NONLINEAR |
+			       VM_PFNMAP | VM_MIXEDMAP))) {
 		if (!vma->anon_vma)
 			return 0;
 	}
@@ -1055,12 +1059,12 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 	if (is_vm_hugetlb_page(vma))
 		return copy_hugetlb_page_range(dst_mm, src_mm, vma);
 
-	if (unlikely(is_pfn_mapping(vma))) {
+	if (unlikely(vma->vm_flags & VM_PFNMAP)) {
 		/*
 		 * We do not free on error cases below as remove_vma
 		 * gets called on error from higher level routine
 		 */
-		ret = track_pfn_vma_copy(vma);
+		ret = track_pfn_copy(vma);
 		if (ret)
 			return ret;
 	}
@@ -1071,8 +1075,12 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 	 * parent mm. And a permission downgrade will only happen if
 	 * is_cow_mapping() returns true.
 	 */
-	if (is_cow_mapping(vma->vm_flags))
-		mmu_notifier_invalidate_range_start(src_mm, addr, end);
+	is_cow = is_cow_mapping(vma->vm_flags);
+	mmun_start = addr;
+	mmun_end   = end;
+	if (is_cow)
+		mmu_notifier_invalidate_range_start(src_mm, mmun_start,
+						    mmun_end);
 
 	ret = 0;
 	dst_pgd = pgd_offset(dst_mm, addr);
@@ -1088,9 +1096,8 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 		}
 	} while (dst_pgd++, src_pgd++, addr = next, addr != end);
 
-	if (is_cow_mapping(vma->vm_flags))
-		mmu_notifier_invalidate_range_end(src_mm,
-						  vma->vm_start, end);
+	if (is_cow)
+		mmu_notifier_invalidate_range_end(src_mm, mmun_start, mmun_end);
 	return ret;
 }
 
@@ -1327,8 +1334,8 @@ static void unmap_single_vma(struct mmu_gather *tlb,
 	if (vma->vm_file)
 		uprobe_munmap(vma, start, end);
 
-	if (unlikely(is_pfn_mapping(vma)))
-		untrack_pfn_vma(vma, 0, 0);
+	if (unlikely(vma->vm_flags & VM_PFNMAP))
+		untrack_pfn(vma, 0, 0);
 
 	if (start != end) {
 		if (unlikely(is_vm_hugetlb_page(vma))) {
@@ -1521,7 +1528,7 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
 				spin_unlock(&mm->page_table_lock);
 				wait_split_huge_page(vma->anon_vma, pmd);
 			} else {
-				page = follow_trans_huge_pmd(mm, address,
+				page = follow_trans_huge_pmd(vma, address,
 							     pmd, flags);
 				spin_unlock(&mm->page_table_lock);
 				goto out;
@@ -1576,12 +1583,12 @@ split_fallthrough:
 		if (page->mapping && trylock_page(page)) {
 			lru_add_drain();  /* push cached pages to LRU */
 			/*
-			 * Because we lock page here and migration is
-			 * blocked by the pte's page reference, we need
-			 * only check for file-cache page truncation.
+			 * Because we lock page here, and migration is
+			 * blocked by the pte's page reference, and we
+			 * know the page is still mapped, we don't even
+			 * need to check for file-cache page truncation.
 			 */
-			if (page->mapping)
-				mlock_vma_page(page);
+			mlock_vma_page(page);
 			unlock_page(page);
 		}
 	}
@@ -2085,6 +2092,11 @@ out:
  * ask for a shared writable mapping!
  *
  * The page does not need to be reserved.
+ *
+ * Usually this function is called from f_op->mmap() handler
+ * under mm->mmap_sem write-lock, so it can change vma->vm_flags.
+ * Caller must set VM_MIXEDMAP on vma if it wants to call this
+ * function from other places, for example from page-fault handler.
  */
 int vm_insert_page(struct vm_area_struct *vma, unsigned long addr,
 			struct page *page)
@@ -2093,7 +2105,11 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr,
 		return -EFAULT;
 	if (!page_count(page))
 		return -EINVAL;
-	vma->vm_flags |= VM_INSERTPAGE;
+	if (!(vma->vm_flags & VM_MIXEDMAP)) {
+		BUG_ON(down_read_trylock(&vma->vm_mm->mmap_sem));
+		BUG_ON(vma->vm_flags & VM_PFNMAP);
+		vma->vm_flags |= VM_MIXEDMAP;
+	}
 	return insert_page(vma, addr, page, vma->vm_page_prot);
 }
 EXPORT_SYMBOL(vm_insert_page);
@@ -2132,7 +2148,7 @@ out:
  * @addr: target user address of this page
  * @pfn: source kernel pfn
  *
- * Similar to vm_inert_page, this allows drivers to insert individual pages
+ * Similar to vm_insert_page, this allows drivers to insert individual pages
  * they've allocated into a user vma. Same comments apply.
  *
  * This function should only be called from a vm_ops->fault handler, and
@@ -2162,14 +2178,11 @@ int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
 
 	if (addr < vma->vm_start || addr >= vma->vm_end)
 		return -EFAULT;
-	if (track_pfn_vma_new(vma, &pgprot, pfn, PAGE_SIZE))
+	if (track_pfn_insert(vma, &pgprot, pfn))
 		return -EINVAL;
 
 	ret = insert_pfn(vma, addr, pfn, pgprot);
 
-	if (ret)
-		untrack_pfn_vma(vma, pfn, PAGE_SIZE);
-
 	return ret;
 }
 EXPORT_SYMBOL(vm_insert_pfn);
@@ -2290,37 +2303,30 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
 	 * rest of the world about it:
 	 *   VM_IO tells people not to look at these pages
 	 *	(accesses can have side effects).
-	 *   VM_RESERVED is specified all over the place, because
-	 *	in 2.4 it kept swapout's vma scan off this vma; but
-	 *	in 2.6 the LRU scan won't even find its pages, so this
-	 *	flag means no more than count its pages in reserved_vm,
-	 * 	and omit it from core dump, even when VM_IO turned off.
 	 *   VM_PFNMAP tells the core MM that the base pages are just
 	 *	raw PFN mappings, and do not have a "struct page" associated
 	 *	with them.
+	 *   VM_DONTEXPAND
+	 *      Disable vma merging and expanding with mremap().
+	 *   VM_DONTDUMP
+	 *      Omit vma from core dump, even when VM_IO turned off.
 	 *
 	 * There's a horrible special case to handle copy-on-write
 	 * behaviour that some programs depend on. We mark the "original"
 	 * un-COW'ed pages by matching them up with "vma->vm_pgoff".
+	 * See vm_normal_page() for details.
 	 */
-	if (addr == vma->vm_start && end == vma->vm_end) {
+	if (is_cow_mapping(vma->vm_flags)) {
+		if (addr != vma->vm_start || end != vma->vm_end)
+			return -EINVAL;
 		vma->vm_pgoff = pfn;
-		vma->vm_flags |= VM_PFN_AT_MMAP;
-	} else if (is_cow_mapping(vma->vm_flags))
-		return -EINVAL;
-
-	vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
+	}
 
-	err = track_pfn_vma_new(vma, &prot, pfn, PAGE_ALIGN(size));
-	if (err) {
-		/*
-		 * To indicate that track_pfn related cleanup is not
-		 * needed from higher level routine calling unmap_vmas
-		 */
-		vma->vm_flags &= ~(VM_IO | VM_RESERVED | VM_PFNMAP);
-		vma->vm_flags &= ~VM_PFN_AT_MMAP;
+	err = track_pfn_remap(vma, &prot, pfn, addr, PAGE_ALIGN(size));
+	if (err)
 		return -EINVAL;
-	}
+
+	vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
 
 	BUG_ON(addr >= end);
 	pfn -= addr >> PAGE_SHIFT;
@@ -2335,7 +2341,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
 	} while (pgd++, addr = next, addr != end);
 
 	if (err)
-		untrack_pfn_vma(vma, pfn, PAGE_ALIGN(size));
+		untrack_pfn(vma, pfn, PAGE_ALIGN(size));
 
 	return err;
 }
@@ -2516,11 +2522,14 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 		spinlock_t *ptl, pte_t orig_pte)
 	__releases(ptl)
 {
-	struct page *old_page, *new_page;
+	struct page *old_page, *new_page = NULL;
 	pte_t entry;
 	int ret = 0;
 	int page_mkwrite = 0;
 	struct page *dirty_page = NULL;
+	unsigned long mmun_start;	/* For mmu_notifiers */
+	unsigned long mmun_end;		/* For mmu_notifiers */
+	bool mmun_called = false;	/* For mmu_notifiers */
 
 	old_page = vm_normal_page(vma, address, orig_pte);
 	if (!old_page) {
@@ -2698,6 +2707,11 @@ gotten:
 	if (mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))
 		goto oom_free_new;
 
+	mmun_start  = address & PAGE_MASK;
+	mmun_end    = (address & PAGE_MASK) + PAGE_SIZE;
+	mmun_called = true;
+	mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+
 	/*
 	 * Re-check the pte - we dropped the lock
 	 */
@@ -2764,6 +2778,8 @@ gotten:
 		page_cache_release(new_page);
 unlock:
 	pte_unmap_unlock(page_table, ptl);
+	if (mmun_called)
+		mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
 	if (old_page) {
 		/*
 		 * Don't let another task, with possibly unlocked vma,
@@ -2801,14 +2817,13 @@ static void unmap_mapping_range_vma(struct vm_area_struct *vma,
 	zap_page_range_single(vma, start_addr, end_addr - start_addr, details);
 }
 
-static inline void unmap_mapping_range_tree(struct prio_tree_root *root,
+static inline void unmap_mapping_range_tree(struct rb_root *root,
 					    struct zap_details *details)
 {
 	struct vm_area_struct *vma;
-	struct prio_tree_iter iter;
 	pgoff_t vba, vea, zba, zea;
 
-	vma_prio_tree_foreach(vma, &iter, root,
+	vma_interval_tree_foreach(vma, root,
 			details->first_index, details->last_index) {
 
 		vba = vma->vm_pgoff;
@@ -2839,7 +2854,7 @@ static inline void unmap_mapping_range_list(struct list_head *head,
 	 * across *all* the pages in each nonlinear VMA, not just the pages
 	 * whose virtual address lies outside the file truncation point.
 	 */
-	list_for_each_entry(vma, head, shared.vm_set.list) {
+	list_for_each_entry(vma, head, shared.nonlinear) {
 		details->nonlinear_vma = vma;
 		unmap_mapping_range_vma(vma, vma->vm_start, vma->vm_end, details);
 	}
@@ -2883,7 +2898,7 @@ void unmap_mapping_range(struct address_space *mapping,
 
 
 	mutex_lock(&mapping->i_mmap_mutex);
-	if (unlikely(!prio_tree_empty(&mapping->i_mmap)))
+	if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap)))
 		unmap_mapping_range_tree(&mapping->i_mmap, &details);
 	if (unlikely(!list_empty(&mapping->i_mmap_nonlinear)))
 		unmap_mapping_range_list(&mapping->i_mmap_nonlinear, &details);