Alistair Popple wrote: > On Mon, Jan 13, 2025 at 07:35:07PM -0800, Dan Williams wrote: > > Alistair Popple wrote: > > [...] > > > ...and here is that aformentioned patch: > > This patch is different from what you originally posted here: > https://yhbt.net/lore/linux-s390/172721874675.497781.3277495908107141898.stgit@xxxxxxxxxxxxxxxxxxxxxxxxx/ > > > -- 8< -- > > Subject: dcssblk: Mark DAX broken, remove FS_DAX_LIMITED support > > > > From: Dan Williams <dan.j.williams@xxxxxxxxx> > > > > The dcssblk driver has long needed special case supoprt to enable > > limited dax operation, so called CONFIG_FS_DAX_LIMITED. This mode > > works around the incomplete support for ZONE_DEVICE on s390 by forgoing > > the ability of dax-mapped pages to support GUP. > > > > Now, pending cleanups to fsdax that fix its reference counting [1] depend on > > the ability of all dax drivers to supply ZONE_DEVICE pages. > > > > To allow that work to move forward, dax support needs to be paused for > > dcssblk until ZONE_DEVICE support arrives. That work has been known for > > a few years [2], and the removal of "pte_devmap" requirements [3] makes the > > conversion easier. > > > > For now, place the support behind CONFIG_BROKEN, and remove PFN_SPECIAL > > (dcssblk was the only user). > > Specifically it no longer removes PFN_SPECIAL. Was this intentional? Or should I > really have picked up the original patch from the mailing list? I think this patch that only removes the dccsblk usage of PFN_SPECIAL is sufficient. Leave the rest to the pfn_t cleanup.
