This is done along the lines of ext4 and xfs. I primarily wanted ->writepages hook at this time so that I could call into dax_writeback_mapping_range(). This in turn will decide which pfns need to be written back. Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx> --- fs/fuse/file.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index f1ad8b95b546..0eecb4097c14 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -2669,6 +2669,16 @@ static int fuse_writepages_fill(struct page *page, return err; } +static int fuse_dax_writepages(struct address_space *mapping, + struct writeback_control *wbc) +{ + + struct inode *inode = mapping->host; + struct fuse_conn *fc = get_fuse_conn(inode); + + return dax_writeback_mapping_range(mapping, fc->dax_dev, wbc); +} + static int fuse_writepages(struct address_space *mapping, struct writeback_control *wbc) { @@ -4021,6 +4031,13 @@ static const struct address_space_operations fuse_file_aops = { .write_end = fuse_write_end, }; +static const struct address_space_operations fuse_dax_file_aops = { + .writepages = fuse_dax_writepages, + .direct_IO = noop_direct_IO, + .set_page_dirty = noop_set_page_dirty, + .invalidatepage = noop_invalidatepage, +}; + void fuse_init_file_inode(struct inode *inode) { struct fuse_inode *fi = get_fuse_inode(inode); @@ -4036,6 +4053,8 @@ void fuse_init_file_inode(struct inode *inode) fi->writepages = RB_ROOT; fi->dmap_tree = RB_ROOT_CACHED; - if (fc->dax_dev) + if (fc->dax_dev) { inode->i_flags |= S_DAX; + inode->i_data.a_ops = &fuse_dax_file_aops; + } } -- 2.25.4