From 9973c98ecfda3a1dfcab981665b5f1e39bcde64a Mon Sep 17 00:00:00 2001 From: Ross Zwisler Date: Fri, 22 Jan 2016 15:10:47 -0800 Subject: dax: add support for fsync/sync To properly handle fsync/msync in an efficient way DAX needs to track dirty pages so it is able to flush them durably to media on demand. The tracking of dirty pages is done via the radix tree in struct address_space. This radix tree is already used by the page writeback infrastructure for tracking dirty pages associated with an open file, and it already has support for exceptional (non struct page*) entries. We build upon these features to add exceptional entries to the radix tree for DAX dirty PMD or PTE pages at fault time. [dan.j.williams@intel.com: fix dax_pmd_dbg build warning] Signed-off-by: Ross Zwisler Cc: "H. Peter Anvin" Cc: "J. Bruce Fields" Cc: "Theodore Ts'o" Cc: Alexander Viro Cc: Andreas Dilger Cc: Dave Chinner Cc: Ingo Molnar Cc: Jan Kara Cc: Jeff Layton Cc: Matthew Wilcox Cc: Thomas Gleixner Cc: Matthew Wilcox Cc: Dave Hansen Signed-off-by: Dan Williams Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/filemap.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'mm/filemap.c') diff --git a/mm/filemap.c b/mm/filemap.c index 1e215fc36c83..2e7c8d980d5e 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -482,6 +482,12 @@ int filemap_write_and_wait_range(struct address_space *mapping, { int err = 0; + if (dax_mapping(mapping) && mapping->nrexceptional) { + err = dax_writeback_mapping_range(mapping, lstart, lend); + if (err) + return err; + } + if (mapping->nrpages) { err = __filemap_fdatawrite_range(mapping, lstart, lend, WB_SYNC_ALL); -- cgit v1.2.3