guest_memfd will be using truncate_inode_folio() to remove folios from
guest_memfd's filemap.

Change-Id: Iab72c6d4138cf19f6efeb38341eabe28ded42fd6
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
---
 include/linux/mm.h    | 1 +
 mm/guestmem_hugetlb.c | 2 +-
 mm/internal.h         | 1 -
 mm/truncate.c         | 1 +
 4 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index e4e73c231ced..74ca6b7d1d43 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2530,6 +2530,7 @@ extern void truncate_pagecache(struct inode *inode, loff_t new);
 extern void truncate_setsize(struct inode *inode, loff_t newsize);
 void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
 void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
+int truncate_inode_folio(struct address_space *mapping, struct folio *folio);
 int generic_error_remove_folio(struct address_space *mapping,
 		struct folio *folio);
 
diff --git a/mm/guestmem_hugetlb.c b/mm/guestmem_hugetlb.c
index 5459ef7eb329..ec5a188ca2a7 100644
--- a/mm/guestmem_hugetlb.c
+++ b/mm/guestmem_hugetlb.c
@@ -4,12 +4,12 @@
  * as an allocator for guest_memfd.
  */
 
-#include <linux/mm_types.h>
 #include <linux/guestmem.h>
 #include <linux/hugetlb.h>
 #include <linux/hugetlb_cgroup.h>
 #include <linux/mempolicy.h>
 #include <linux/mm.h>
+#include <linux/mm_types.h>
 #include <linux/pagemap.h>
 
 #include <uapi/linux/guestmem.h>
diff --git a/mm/internal.h b/mm/internal.h
index 25a29872c634..a1694f030539 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -448,7 +448,6 @@ unsigned find_lock_entries(struct address_space *mapping, pgoff_t *start,
 unsigned find_get_entries(struct address_space *mapping, pgoff_t *start,
 		pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices);
 void filemap_free_folio(struct address_space *mapping, struct folio *folio);
-int truncate_inode_folio(struct address_space *mapping, struct folio *folio);
 bool truncate_inode_partial_folio(struct folio *folio, loff_t start,
 		loff_t end);
 long mapping_evict_folio(struct address_space *mapping, struct folio *folio);
diff --git a/mm/truncate.c b/mm/truncate.c
index 057e4aa73aa9..4baab1e5d2cf 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -176,6 +176,7 @@ int truncate_inode_folio(struct address_space *mapping, struct folio *folio)
 	filemap_remove_folio(folio);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(truncate_inode_folio);
 
 /*
  * Handle partial folios.  The folio may be entirely within the
-- 
2.49.0.1045.g170613ef41-goog