[RFC PATCH v1 06/10] mm: filemap: Export filemap_remove_folio()

[Ackerley Tng <ackerleytng@google.com>]

Export filemap_remove_folio() for use by KVM.

KVM requires this function to remove folios from guest_memfd's filemap.

guest_memfd used to rely on higher-level, exported truncation functions. To
track memory that is actually allocated (i.e. i_blocks, st_blocks),
guest_memfd will need a custom truncation function to do accounting cleanup
and will be using filemap_remove_folio() for truncation.

Signed-off-by: Ackerley Tng <ackerleytng@google.com>
---
 mm/filemap.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/filemap.c b/mm/filemap.c
index ebd75684cb0a7..379d62239fc5f 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -49,6 +49,7 @@
 #include <linux/sched/mm.h>
 #include <linux/sysctl.h>
 #include <linux/pgalloc.h>
+#include <linux/kvm_types.h>
 
 #include <asm/tlbflush.h>
 #include "internal.h"
@@ -262,6 +263,7 @@ void filemap_remove_folio(struct folio *folio)
 
 	filemap_free_folio(mapping, folio);
 }
+EXPORT_SYMBOL_FOR_KVM(filemap_remove_folio);
 
 /*
  * page_cache_delete_batch - delete several folios from page cache
-- 
2.53.0.345.g96ddfc5eaa-goog