On Mon, Apr 5, 2021 at 4:31 AM Aneesh Kumar K.V <[email protected]> wrote: > > Vaibhav Jain <[email protected]> writes: > > > In case a platform doesn't provide explicit flush-hints but provides an > > explicit flush callback via ND_REGION_ASYNC region flag, then > > nvdimm_has_flush() still returns '0' indicating that writes do not > > require flushing. This happens on PPC64 with patch at [1] applied, > > where 'deep_flush' of a region was denied even though an explicit > > flush function was provided. > > > > Fix this by adding a condition to nvdimm_has_flush() to test for the > > ND_REGION_ASYNC flag on the region and see if a 'region->flush' > > callback is assigned. > > > > May be this should have > Fixes: c5d4355d10d4 ("libnvdimm: nd_region flush callback support")
Yes, thanks for that. > > Without this we will mark the pmem disk not having FUA support? Yes. > > > > References: > > [1] "powerpc/papr_scm: Implement support for H_SCM_FLUSH hcall" > > https://lore.kernel.org/linux-nvdimm/161703936121.36.7260632399 > > 582101498.stgit@e1fbed493c87 > > > > Reported-by: Shivaprasad G Bhat <[email protected]> > > Signed-off-by: Vaibhav Jain <[email protected]> > > --- > > drivers/nvdimm/region_devs.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c > > index ef23119db574..e05cc9f8a9fd 100644 > > --- a/drivers/nvdimm/region_devs.c > > +++ b/drivers/nvdimm/region_devs.c > > @@ -1239,6 +1239,11 @@ int nvdimm_has_flush(struct nd_region *nd_region) > > || !IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API)) > > return -ENXIO; > > > > + /* Test if an explicit flush function is defined */ > > + if (test_bit(ND_REGION_ASYNC, &nd_region->flags) && nd_region->flush) > > + return 1; > > > + > > + /* Test if any flush hints for the region are available */ > > for (i = 0; i < nd_region->ndr_mappings; i++) { > > struct nd_mapping *nd_mapping = &nd_region->mapping[i]; > > struct nvdimm *nvdimm = nd_mapping->nvdimm; > > @@ -1249,8 +1254,8 @@ int nvdimm_has_flush(struct nd_region *nd_region) > > } > > > > /* > > - * The platform defines dimm devices without hints, assume > > - * platform persistence mechanism like ADR > > + * The platform defines dimm devices without hints nor explicit flush, > > + * assume platform persistence mechanism like ADR > > */ > > return 0; > > } > > -- > > 2.30.2 > > _______________________________________________ > > Linux-nvdimm mailing list -- [email protected] > > To unsubscribe send an email to [email protected] _______________________________________________ Linux-nvdimm mailing list -- [email protected] To unsubscribe send an email to [email protected]
