[RFC PATCH 06/19] mm: hugetlb: Provide hugetlb_filemap_add_folio()

[Ackerley Tng]

hstate_inode() is hugetlbfs-specific, limiting
hugetlb_add_to_page_cache() to hugetlbfs.

hugetlb_filemap_add_folio() allows hstate to be specified and further
separates hugetlb from hugetlbfs.

Signed-off-by: Ackerley Tng <ackerleytng@google.com>
---
 include/linux/hugetlb.h |  2 ++
 mm/hugetlb.c            | 13 ++++++++++---
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 14df89d1642c..7d49048c5a2a 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -756,6 +756,8 @@ struct folio *alloc_hugetlb_folio_nodemask(struct hstate 
*h, int preferred_nid,
                                nodemask_t *nmask, gfp_t gfp_mask);
 struct folio *alloc_hugetlb_folio_vma(struct hstate *h, struct vm_area_struct 
*vma,
                                unsigned long address);
+int hugetlb_filemap_add_folio(struct address_space *mapping, struct hstate *h,
+                             struct folio *folio, pgoff_t idx);
 int hugetlb_add_to_page_cache(struct folio *folio, struct address_space 
*mapping,
                        pgoff_t idx);
 void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma,
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 99ab4bbdb2ce..d16c6417b90f 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5665,11 +5665,10 @@ static bool hugetlbfs_pagecache_present(struct hstate 
*h,
        return present;
 }
 
-int hugetlb_add_to_page_cache(struct folio *folio, struct address_space 
*mapping,
-                          pgoff_t idx)
+int hugetlb_filemap_add_folio(struct address_space *mapping, struct hstate *h,
+                             struct folio *folio, pgoff_t idx)
 {
        struct inode *inode = mapping->host;
-       struct hstate *h = hstate_inode(inode);
        int err;
 
        __folio_set_locked(folio);
@@ -5693,6 +5692,14 @@ int hugetlb_add_to_page_cache(struct folio *folio, 
struct address_space *mapping
        return 0;
 }
 
+int hugetlb_add_to_page_cache(struct folio *folio, struct address_space 
*mapping,
+                             pgoff_t idx)
+{
+       struct hstate *h = hstate_inode(mapping->host);
+
+       return hugetlb_filemap_add_folio(mapping, h, folio, idx);
+}
+
 static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma,
                                                  struct address_space *mapping,
                                                  pgoff_t idx,
-- 
2.41.0.rc0.172.g3f132b7071-goog