[RFC PATCH 3/5] hugetlbfs: move routine remove_huge_page to hugetlb.c

[Mike Kravetz <mike.kravetz@oracle.com>]

In preparation for code in hugetlb.c removing pages from the page
cache, move remove_huge_page to hugetlb.c.  For a more descriptive
global name, rename to hugetlb_delete_from_page_cache.  Also,
rename huge_add_to_page_cache to be consistent.

Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
---
 fs/hugetlbfs/inode.c    | 24 ++++++++----------------
 include/linux/hugetlb.h |  3 ++-
 mm/hugetlb.c            | 15 +++++++++++----
 3 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 56cd75b6cfc0..0cf352555354 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -396,13 +396,6 @@ static int hugetlbfs_write_end(struct file *file, struct address_space *mapping,
 	return -EINVAL;
 }
 
-static void remove_huge_page(struct page *page)
-{
-	ClearPageDirty(page);
-	ClearPageUptodate(page);
-	delete_from_page_cache(page);
-}
-
 static void
 hugetlb_vmdelete_list(struct rb_root_cached *root, pgoff_t start, pgoff_t end)
 {
@@ -514,15 +507,14 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart,
 			lock_page(page);
 			/*
 			 * We must free the huge page and remove from page
-			 * cache (remove_huge_page) BEFORE removing the
-			 * region/reserve map (hugetlb_unreserve_pages).  In
-			 * rare out of memory conditions, removal of the
-			 * region/reserve map could fail. Correspondingly,
-			 * the subpool and global reserve usage count can need
-			 * to be adjusted.
+			 * cache BEFORE removing the region/reserve map
+			 * (hugetlb_unreserve_pages).  In rare out of memory
+			 * conditions, removal of the region/reserve map could
+			 * fail. Correspondingly, the subpool and global
+			 * reserve usage count can need to be adjusted.
 			 */
 			VM_BUG_ON(HPageRestoreReserve(page));
-			remove_huge_page(page);
+			hugetlb_delete_from_page_cache(page);
 			freed++;
 			if (!truncate_op) {
 				if (unlikely(hugetlb_unreserve_pages(inode,
@@ -720,7 +712,7 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
 		}
 		clear_huge_page(page, addr, pages_per_huge_page(h));
 		__SetPageUptodate(page);
-		error = huge_add_to_page_cache(page, mapping, index);
+		error = hugetlb_add_to_page_cache(page, mapping, index);
 		if (unlikely(error)) {
 			restore_reserve_on_error(h, &pseudo_vma, addr, page);
 			put_page(page);
@@ -972,7 +964,7 @@ static int hugetlbfs_error_remove_page(struct address_space *mapping,
 	struct inode *inode = mapping->host;
 	pgoff_t index = page->index;
 
-	remove_huge_page(page);
+	hugetlb_delete_from_page_cache(page);
 	if (unlikely(hugetlb_unreserve_pages(inode, index, index + 1, 1)))
 		hugetlb_fix_reserve_counts(inode);
 
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index d1897a69c540..2cf99d769f61 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -640,8 +640,9 @@ struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
 				nodemask_t *nmask, gfp_t gfp_mask);
 struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma,
 				unsigned long address);
-int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
+int hugetlb_add_to_page_cache(struct page *page, struct address_space *mapping,
 			pgoff_t idx);
+void hugetlb_delete_from_page_cache(struct page *page);
 void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma,
 				unsigned long address, struct page *page);
 
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 8fa2386bf7c0..c6d76f61de98 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5281,7 +5281,7 @@ static bool hugetlbfs_pagecache_present(struct hstate *h,
 	return page != NULL;
 }
 
-int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
+int hugetlb_add_to_page_cache(struct page *page, struct address_space *mapping,
 			   pgoff_t idx)
 {
 	struct inode *inode = mapping->host;
@@ -5304,6 +5304,13 @@ int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
 	return 0;
 }
 
+void hugetlb_delete_from_page_cache(struct page *page)
+{
+	ClearPageDirty(page);
+	ClearPageUptodate(page);
+	delete_from_page_cache(page);
+}
+
 static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma,
 						  struct address_space *mapping,
 						  pgoff_t idx,
@@ -5412,7 +5419,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
 		new_page = true;
 
 		if (vma->vm_flags & VM_MAYSHARE) {
-			int err = huge_add_to_page_cache(page, mapping, idx);
+			int err = hugetlb_add_to_page_cache(page, mapping, idx);
 			if (err) {
 				put_page(page);
 				if (err == -EEXIST)
@@ -5788,11 +5795,11 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
 
 		/*
 		 * Serialization between remove_inode_hugepages() and
-		 * huge_add_to_page_cache() below happens through the
+		 * hugetlb_add_to_page_cache() below happens through the
 		 * hugetlb_fault_mutex_table that here must be hold by
 		 * the caller.
 		 */
-		ret = huge_add_to_page_cache(page, mapping, idx);
+		ret = hugetlb_add_to_page_cache(page, mapping, idx);
 		if (ret)
 			goto out_release_nounlock;
 		page_in_pagecache = true;
-- 
2.35.1