[PATCH v2 0/7] dax: I/O path enhancements

[Ross Zwisler]

The goal of this series is to enhance the DAX I/O path so that all operations
that store data (I/O writes, zeroing blocks, punching holes, etc.) properly
synchronize the stores to media using the PMEM API.  This ensures that the data
DAX is writing is durable on media before the operation completes.

Patches 1-4 are a few random cleanups.

Changes from v1:
 - Removed patches to PMEM for the "read flush" _DSM flag.  These are different
   enough that they deserve their own series, and they have a separate baseline
   which is currently moving (Dan's memremap() series).
 - Added clear_pmem() PMEM API to zero DAX memory and flush it in one call.
   (Dave)
 - Open coded flushing in arch_wb_cache_pmem() instead of adding a generic
   clwb_flush_range().  This allowed me to avoid having extra memory barriers
   and instead rely completely on arch_wmb_pmem() for ordering. (Dave)
 - Moved the arch implementation of the PMEM API into it's own arch header
   (Christoph).

Ross Zwisler (7):
  brd: make rd_size static
  pmem, x86: move x86 PMEM API to new pmem.h header
  pmem: remove layer when calling arch_has_wmb_pmem()
  pmem, x86: clean up conditional pmem includes
  pmem: add wb_cache_pmem() and clear_pmem()
  dax: update I/O path to do proper PMEM flushing
  pmem, dax: have direct_access use __pmem annotation

 Documentation/filesystems/Locking |   3 +-
 MAINTAINERS                       |   1 +
 arch/powerpc/sysdev/axonram.c     |   7 ++-
 arch/x86/include/asm/cacheflush.h |  71 ----------------------
 arch/x86/include/asm/pmem.h       | 123 ++++++++++++++++++++++++++++++++++++++
 drivers/block/brd.c               |   6 +-
 drivers/nvdimm/pmem.c             |   4 +-
 drivers/s390/block/dcssblk.c      |  10 ++--
 fs/block_dev.c                    |   2 +-
 fs/dax.c                          |  73 ++++++++++++++--------
 include/linux/blkdev.h            |   8 +--
 include/linux/pmem.h              |  66 ++++++++++++++++----
 12 files changed, 247 insertions(+), 127 deletions(-)
 create mode 100644 arch/x86/include/asm/pmem.h

-- 
2.1.0