Re: [PATCH v2 7/7] pmem, dax: have direct_access use __pmem annotation

On Thu, 2015-08-13 at 14:20 -0700, Dan Williams wrote:

On Thu, Aug 13, 2015 at 9:51 AM, Ross Zwisler
[off-list ref] wrote:

quoted

Update the annotation for the kaddr pointer returned by direct_access()
so that it is a __pmem pointer.  This is consistent with the PMEM driver
and with how this direct_access() pointer is used in the DAX code.

Signed-off-by: Ross Zwisler <redacted>
---
 Documentation/filesystems/Locking |  3 ++-
 arch/powerpc/sysdev/axonram.c     |  7 ++++---
 drivers/block/brd.c               |  4 ++--
 drivers/nvdimm/pmem.c             |  4 ++--
 drivers/s390/block/dcssblk.c      | 10 +++++----
 fs/block_dev.c                    |  2 +-
 fs/dax.c                          | 44 +++++++++++++++++++++------------------
 include/linux/blkdev.h            |  8 +++----
 8 files changed, 45 insertions(+), 37 deletions(-)

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 6a34a0f..06d4434 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking

@@ -397,7 +397,8 @@ prototypes:
        int (*release) (struct gendisk *, fmode_t);
        int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
        int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
-       int (*direct_access) (struct block_device *, sector_t, void **, unsigned long *);
+       int (*direct_access) (struct block_device *, sector_t, void __pmem **,
+                               unsigned long *);

So this collides with the __pfn_t work.  I think the we have a
reasonable chance of getting that in to 4.3, so I'd wait to see if we
hit any major roadblocks with that set [1] before merging these.

[1]: https://lists.01.org/pipermail/linux-nvdimm/2015-August/001803.html

Fair enough.  Yea, I hadn't merged with that series yet a) because I didn't
know when its review cycle would settle down and b) because that series hadn't
pulled in changes from Matthew for PMD support, which I was originally using
as a baseline.

I'll merge with your code for v3.