[GIT PULL] libnvdimm fixes for 4.3-rc2

["Williams, Dan J" <dan.j.williams@intel.com>]

Hi Linus, please pull from:

    git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm libnvdimm-fixes

...to receive:

1/ A boot regression (since v4.2) fix for some ARM configurations from
Tyler

2/ Regression (since v4.1) fixes for mkfs.xfs on a DAX enabled device
from Jeff.  These are tagged for -stable.

3/ A pair of locking fixes from Axel that are hidden from lockdep since
they involve device_lock().  The "btt" one is tagged for -stable, the
other only applies to the new "pfn" mechanism in v4.3.

4/ A fix for the pmem ->rw_page() path to use wmb_pmem() from Ross.

Full log and diff below.

---

The following changes since commit 6ff33f3902c3b1c5d0db6b1e2c70b6d76fba357f:

  Linux 4.3-rc1 (2015-09-12 16:35:56 -0700)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm libnvdimm-fixes

for you to fetch changes up to ae4f976968896f8f41b3a7aa21be6146492211e5:

  mm: fix type cast in __pfn_to_phys() (2015-09-19 03:58:10 -0400)

----------------------------------------------------------------
Axel Lin (2):
      libnvdimm: btt_devs: Fix locking in namespace_store
      libnvdimm: pfn_devs: Fix locking in namespace_store

Jeff Moyer (2):
      dax: fix O_DIRECT I/O to the last block of a blockdev
      blockdev: don't set S_DAX for misaligned partitions

Ross Zwisler (1):
      pmem: add proper fencing to pmem_rw_page()

Tyler Baker (1):
      mm: fix type cast in __pfn_to_phys()

 drivers/nvdimm/btt_devs.c          | 4 ++--
 drivers/nvdimm/pfn_devs.c          | 4 ++--
 drivers/nvdimm/pmem.c              | 2 ++
 fs/block_dev.c                     | 7 +++++++
 fs/dax.c                           | 3 ++-
 include/asm-generic/memory_model.h | 2 +-
 6 files changed, 16 insertions(+), 6 deletions(-)

commit ae4f976968896f8f41b3a7aa21be6146492211e5
Author: Tyler Baker <tyler.baker@linaro.org>
Date:   Sat Sep 19 03:58:10 2015 -0400

    mm: fix type cast in __pfn_to_phys()
    
    The various definitions of __pfn_to_phys() have been consolidated to
    use a generic macro in include/asm-generic/memory_model.h. This hit
    mainline in the form of 012dcef3f058 "mm: move __phys_to_pfn and
    __pfn_to_phys to asm/generic/memory_model.h". When the generic macro
    was implemented the type cast to phys_addr_t was dropped which caused
    boot regressions on ARM platforms with more than 4GB of memory and
    LPAE enabled.
    
    It was suggested to use PFN_PHYS() defined in include/linux/pfn.h
    as provides the correct logic and avoids further duplication.
    
    Reported-by: kernelci.org bot <bot@kernelci.org>
    Suggested-by: Dan Williams <dan.j.williams@intel.com>
    Signed-off-by: Tyler Baker <tyler.baker@linaro.org>
    Signed-off-by: Dan Williams <dan.j.williams@intel.com>

commit ba8fe0f85e15d047686caf8a42463b592c63c98c
Author: Ross Zwisler <ross.zwisler@linux.intel.com>
Date:   Wed Sep 16 14:52:21 2015 -0600

    pmem: add proper fencing to pmem_rw_page()
    
    pmem_rw_page() needs to call wmb_pmem() on writes to make sure that the
    newly written data is durable.  This flow was added to pmem_rw_bytes()
    and pmem_make_request() with this commit:
    
    commit 61031952f4c8 ("arch, x86: pmem api for ensuring durability of
    	persistent memory updates")
    
    ...the pmem_rw_page() path was missed.
    
    Cc: <stable@vger.kernel.org>
    Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
    Signed-off-by: Dan Williams <dan.j.williams@intel.com>

commit 4ca8b57a0af145f4e791f21dbca6ad789da9ee8b
Author: Axel Lin <axel.lin@ingics.com>
Date:   Wed Sep 16 21:25:38 2015 +0800

    libnvdimm: pfn_devs: Fix locking in namespace_store
    
    Always take device_lock() before nvdimm_bus_lock() to prevent deadlock.
    
    Signed-off-by: Axel Lin <axel.lin@ingics.com>
    Signed-off-by: Dan Williams <dan.j.williams@intel.com>

commit 4be9c1fc3df9c3b03c9bde8aec5e44fc73996a3f
Author: Axel Lin <axel.lin@ingics.com>
Date:   Wed Sep 16 21:24:47 2015 +0800

    libnvdimm: btt_devs: Fix locking in namespace_store
    
    Always take device_lock() before nvdimm_bus_lock() to prevent deadlock.
    
    Cc: <stable@vger.kernel.org>
    Signed-off-by: Axel Lin <axel.lin@ingics.com>
    Signed-off-by: Dan Williams <dan.j.williams@intel.com>

commit f0b2e563bc419df7c1b3d2f494574c25125f6aed
Author: Jeff Moyer <jmoyer@redhat.com>
Date:   Fri Aug 14 16:15:32 2015 -0400

    blockdev: don't set S_DAX for misaligned partitions
    
    The dax code doesn't currently support misaligned partitions,
    so disable O_DIRECT via dax until such time as that support
    materializes.
    
    Cc: <stable@vger.kernel.org>
    Suggested-by: Boaz Harrosh <boaz@plexistor.com>
    Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
    Signed-off-by: Dan Williams <dan.j.williams@intel.com>

commit e94f5a2285fc94202a9efb2c687481f29b64132c
Author: Jeff Moyer <jmoyer@redhat.com>
Date:   Fri Aug 14 16:15:31 2015 -0400

    dax: fix O_DIRECT I/O to the last block of a blockdev
    
    commit bbab37ddc20b (block: Add support for DAX reads/writes to
    block devices) caused a regression in mkfs.xfs.  That utility
    sets the block size of the device to the logical block size
    using the BLKBSZSET ioctl, and then issues a single sector read
    from the last sector of the device.  This results in the dax_io
    code trying to do a page-sized read from 512 bytes from the end
    of the device.  The result is -ERANGE being returned to userspace.
    
    The fix is to align the block to the page size before calling
    get_block.
    
    Thanks to willy for simplifying my original patch.
    
    Cc: <stable@vger.kernel.org>
    Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
    Tested-by:  Linda Knippers <linda.knippers@hp.com>
    Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c
index 59ad54a63d9f..cb477518dd0e 100644
--- a/drivers/nvdimm/btt_devs.c
+++ b/drivers/nvdimm/btt_devs.c
@@ -128,13 +128,13 @@ static ssize_t namespace_store(struct device *dev,
 	struct nd_btt *nd_btt = to_nd_btt(dev);
 	ssize_t rc;
 
-	nvdimm_bus_lock(dev);
 	device_lock(dev);
+	nvdimm_bus_lock(dev);
 	rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
 	dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
 			rc, buf, buf[len - 1] == '\n' ? "" : "\n");
-	device_unlock(dev);
 	nvdimm_bus_unlock(dev);
+	device_unlock(dev);
 
 	return rc;
 }
diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c
index 3fd7d0d81a47..71805a1aa0f3 100644
--- a/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@ -148,13 +148,13 @@ static ssize_t namespace_store(struct device *dev,
 	struct nd_pfn *nd_pfn = to_nd_pfn(dev);
 	ssize_t rc;
 
-	nvdimm_bus_lock(dev);
 	device_lock(dev);
+	nvdimm_bus_lock(dev);
 	rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len);
 	dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
 			rc, buf, buf[len - 1] == '\n' ? "" : "\n");
-	device_unlock(dev);
 	nvdimm_bus_unlock(dev);
+	device_unlock(dev);
 
 	return rc;
 }
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index b9525385c0dc..0ba6a978f227 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -92,6 +92,8 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector,
 	struct pmem_device *pmem = bdev->bd_disk->private_data;
 
 	pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector);
+	if (rw & WRITE)
+		wmb_pmem();
 	page_endio(page, rw & WRITE, 0);
 
 	return 0;
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 22ea424ee741..073bb57adab1 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1242,6 +1242,13 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
 				goto out_clear;
 			}
 			bd_set_size(bdev, (loff_t)bdev->bd_part->nr_sects << 9);
+			/*
+			 * If the partition is not aligned on a page
+			 * boundary, we can't do dax I/O to it.
+			 */
+			if ((bdev->bd_part->start_sect % (PAGE_SIZE / 512)) ||
+			    (bdev->bd_part->nr_sects % (PAGE_SIZE / 512)))
+				bdev->bd_inode->i_flags &= ~S_DAX;
 		}
 	} else {
 		if (bdev->bd_contains == bdev) {
diff --git a/fs/dax.c b/fs/dax.c
index 93bf2f990ace..7ae6df7ea1d2 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -119,7 +119,8 @@ static ssize_t dax_io(struct inode *inode, struct iov_iter *iter,
 		size_t len;
 		if (pos == max) {
 			unsigned blkbits = inode->i_blkbits;
-			sector_t block = pos >> blkbits;
+			long page = pos >> PAGE_SHIFT;
+			sector_t block = page << (PAGE_SHIFT - blkbits);
 			unsigned first = pos - (block << blkbits);
 			long size;
 
diff --git a/include/asm-generic/memory_model.h b/include/asm-generic/memory_model.h
index f20f407ce45d..4b4b056a6eb0 100644
--- a/include/asm-generic/memory_model.h
+++ b/include/asm-generic/memory_model.h
@@ -73,7 +73,7 @@
  * Convert a physical address to a Page Frame Number and back
  */
 #define	__phys_to_pfn(paddr)	((unsigned long)((paddr) >> PAGE_SHIFT))
-#define	__pfn_to_phys(pfn)	((pfn) << PAGE_SHIFT)
+#define	__pfn_to_phys(pfn)	PFN_PHYS(pfn)
 
 #define page_to_pfn __page_to_pfn
 #define pfn_to_page __pfn_to_page