On Mon, 2022-01-17 at 13:47 +0000, Matthew Wilcox wrote:
> On Mon, Jan 17, 2022 at 12:44:33PM +0000, David Howells wrote:
> > + if (ceph_caps_issued(ci) & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) {
> > + folio = filemap_get_folio(inode->i_mapping, 0);
> > + if (folio) {
> > + if (folio_test_uptodate(folio)) {
> > from_pagecache = true;
> > - lock_page(page);
> > + folio_lock(folio);
> > } else {
> > - put_page(page);
> > - page = NULL;
> > + folio_put(folio);
> > + folio = NULL;
>
> This all falls very much under "doing it the hard way", and quite
> possibly under the "actively buggy with races" category.
>
> read_mapping_folio() does what you want, as long as you pass 'filp'
> as your 'void *data'. I should fix that type ...
>
That would be nicer, I think. If you do that though, then patch #3
probably needs to come first in the series...
--
Jeff Layton <jlayton@xxxxxxxxxx>
