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 --- include/linux/iomap.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux/iomap.h') diff --git a/include/linux/iomap.h b/include/linux/iomap.h index e2b836c2e119..54f50d34fd9d 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -58,7 +58,11 @@ struct vm_fault; #define IOMAP_F_DIRTY (1U << 1) #define IOMAP_F_SHARED (1U << 2) #define IOMAP_F_MERGED (1U << 3) +#ifdef CONFIG_BUFFER_HEAD #define IOMAP_F_BUFFER_HEAD (1U << 4) +#else +#define IOMAP_F_BUFFER_HEAD 0 +#endif /* CONFIG_BUFFER_HEAD */ #define IOMAP_F_XATTR (1U << 5) /* -- cgit v1.2.3