Changes since v3 [1]: - Collect Aneesh's Reviewed-by for Patch1-Patch3 - Add commentary to "libnvdimm/namespace: Enforce memremap_compat_align()" to clarify alignment validation and why start_pad is deprecated (Aneesh)
[1]: http://lore.kernel.org/r/158291746615.1609624.7591692546429050845.st...@dwillia2-desk3.amr.corp.intel.com --- Patch "mm/memremap_pages: Introduce memremap_compat_align()" still needs a PowerPC maintainer ack for the touches to arch/powerpc/mm/ioremap.c. --- Aneesh reports that PowerPC requires 16MiB alignment for the address range passed to devm_memremap_pages(), and Jeff reports that it is possible to create a misaligned namespace which blocks future namespace creation in that region. Both of these issues require namespace alignment to be managed at the region level rather than padding at the namespace level which has been a broken approach to date. Introduce memremap_compat_align() to indicate the hard requirements of an arch's memremap_pages() implementation. Use the maximum known memremap_compat_align() to set the default namespace alignment for libnvdimm. Consult that alignment when allocating free space. Finally, allow the default region alignment to be overridden to maintain the same namespace creation capability as previous kernels (modulo dax operation not being supported with a non-zero start_pad). The ndctl unit tests, which have some misaligned namespace assumptions, are updated to use the alignment override where necessary. Thanks to Aneesh for early feedback and testing on this change to alignment handling. --- Dan Williams (5): mm/memremap_pages: Introduce memremap_compat_align() libnvdimm/pfn: Prevent raw mode fallback if pfn-infoblock valid libnvdimm/namespace: Enforce memremap_compat_align() libnvdimm/region: Introduce NDD_LABELING libnvdimm/region: Introduce an 'align' attribute arch/powerpc/Kconfig | 1 arch/powerpc/mm/ioremap.c | 21 +++++ arch/powerpc/platforms/pseries/papr_scm.c | 2 drivers/acpi/nfit/core.c | 4 + drivers/nvdimm/dimm.c | 2 drivers/nvdimm/dimm_devs.c | 95 +++++++++++++++++---- drivers/nvdimm/namespace_devs.c | 28 +++++- drivers/nvdimm/nd.h | 3 - drivers/nvdimm/pfn.h | 12 +++ drivers/nvdimm/pfn_devs.c | 40 +++++++-- drivers/nvdimm/region_devs.c | 132 ++++++++++++++++++++++++++--- include/linux/libnvdimm.h | 2 include/linux/memremap.h | 8 ++ include/linux/mmzone.h | 1 lib/Kconfig | 3 + mm/memremap.c | 23 +++++ 16 files changed, 330 insertions(+), 47 deletions(-) base-commit: 1d0827b75ee7df497f611a2ac412a88135fb0ef5
