From: Huaisheng Ye <yehs1@xxxxxxxxxx> Some functions within fs/dax and dax/super don't need to get kaddr from direct_access. Assigning NULL to kaddr to ->direct_access() is more straightforward and simple than offering a useless local pointer. So all direct_access() need to check the validity of second rank pointer kaddr for NULL assignment. If kaddr equals to NULL, it doesn't need to calculate its value. * This series are supplement to [PATCH v2 00/14]mm: Asynchronous + multithreaded memmap init for ZONE_DEVICE. [1] [1]: https://lkml.org/lkml/2018/7/16/828 Huaisheng Ye (5): libnvdimm, pmem: Allow a NULL-kaddr to ->direct_access() tools/testing/nvdimm: Allow a NULL-kaddr to ->direct_access() s390, dcssblk: Allow a NULL-kaddr to ->direct_access() filesystem-dax: Do not request a pointer kaddr when not required dax/super: Do not request a pointer kaddr when not required drivers/dax/super.c | 3 +-- drivers/nvdimm/pmem.c | 4 +++- drivers/s390/block/dcssblk.c | 3 ++- fs/dax.c | 3 +-- tools/testing/nvdimm/pmem-dax.c | 6 ++++-- 5 files changed, 11 insertions(+), 8 deletions(-) -- 1.8.3.1
