From 07073eb01c5f630344bc1c3e56b0e0d94aedf919 Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 14 Feb 2023 15:01:42 +0000 Subject: splice: Add a func to do a splice from a buffered file without ITER_PIPE Provide a function to do splice read from a buffered file, pulling the folios out of the pagecache directly by calling filemap_get_pages() to do any required reading and then pasting the returned folios into the pipe. A helper function is provided to do the actual folio pasting and will handle multipage folios by splicing as many of the relevant subpages as will fit into the pipe. The code is loosely based on filemap_read() and might belong in mm/filemap.c with that as it needs to use filemap_get_pages(). Signed-off-by: David Howells Reviewed-by: Jens Axboe cc: Christoph Hellwig cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Signed-off-by: Steve French --- mm/internal.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'mm/internal.h') diff --git a/mm/internal.h b/mm/internal.h index bcf75a8b032d..6d4ca98f3844 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -794,6 +794,12 @@ struct migration_target_control { gfp_t gfp_mask; }; +/* + * mm/filemap.c + */ +size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, + struct folio *folio, loff_t fpos, size_t size); + /* * mm/vmalloc.c */ -- cgit v1.2.3