From 925c86a19bacf8ce10eb666328fb3fa5aff7b951 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 1 Aug 2023 19:22:01 +0200 Subject: fs: add CONFIG_BUFFER_HEAD Add a new config option that controls building the buffer_head code, and select it from all file systems and stacking drivers that need it. For the block device nodes and alternative iomap based buffered I/O path is provided when buffer_head support is not enabled, and iomap needs a a small tweak to define the IOMAP_F_BUFFER_HEAD flag to 0 to not call into the buffer_head code when it doesn't exist. Otherwise this is just Kconfig and ifdef changes. Signed-off-by: Christoph Hellwig Reviewed-by: Luis Chamberlain Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20230801172201.1923299-7-hch@lst.de Signed-off-by: Jens Axboe --- mm/migrate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'mm/migrate.c') diff --git a/mm/migrate.c b/mm/migrate.c index 24baad2571e3..fe6f8d454aff 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -684,7 +684,7 @@ int migrate_folio(struct address_space *mapping, struct folio *dst, } EXPORT_SYMBOL(migrate_folio); -#ifdef CONFIG_BLOCK +#ifdef CONFIG_BUFFER_HEAD /* Returns true if all buffers are successfully locked */ static bool buffer_migrate_lock_buffers(struct buffer_head *head, enum migrate_mode mode) @@ -837,7 +837,7 @@ int buffer_migrate_folio_norefs(struct address_space *mapping, return __buffer_migrate_folio(mapping, dst, src, mode, true); } EXPORT_SYMBOL_GPL(buffer_migrate_folio_norefs); -#endif +#endif /* CONFIG_BUFFER_HEAD */ int filemap_migrate_folio(struct address_space *mapping, struct folio *dst, struct folio *src, enum migrate_mode mode) -- cgit v1.2.3