[GIT PULL] libnvdimm ABI fixup for 4.2

[Williams, Dan J]

Hi Linus, please pull from:

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

...to receive one final fix for 4.2.

I pushed back on this change quite hard given the late date, that it
appears to be purely cosmetic, sysfs is not necessarily meant to be a
user friendly UI, and the kernel interprets the reversed polarity of the
ACPI_NFIT_MEM_ARMED flag correctly.  When this flag is set, the energy
source of an NVDIMM is not armed and any new writes to the DIMM may not
be preserved.

However, Bob Moore warned me that it is important to get these things
named correctly wherever they appear otherwise we run the risk of a less
than cautious firmware engineer implementing the polarity the wrong way.
Once a mistake like that escapes into production platforms the flag
becomes useless and we need to move to a new bit position.

Bob has agreed to take a change through ACPICA to rename
ACPI_NFIT_MEM_ARMED to ACPI_NFIT_MEM_NOT_ARMED, and the patch below from
Toshi brings the sysfs representation of these flags in line with their
respective polarities.

Please pull for 4.2 as this is the first kernel to expose the ACPI NFIT
sysfs representation, and this is likely a kernel that firmware
developers will be using for checking out their NVDIMM enabling.

The following changes since commit de4a196c02a2a2631b516d90da6e8d052ccb07e8:

  nfit, nd_blk: BLK status register is only 32 bits (2015-08-25 19:42:01 -0400)

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 402bae597ec68b84498432f5a0069f28bfb807d6:

  nfit: Clarify memory device state flags strings (2015-08-27 14:35:58 -0400)

----------------------------------------------------------------
Toshi Kani (1):
      nfit: Clarify memory device state flags strings

 drivers/acpi/nfit.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

commit 402bae597ec68b84498432f5a0069f28bfb807d6
Author: Toshi Kani <toshi.kani@xxxxxx>
Date:   Wed Aug 26 10:20:23 2015 -0600

    nfit: Clarify memory device state flags strings
    
    ACPI 6.0 NFIT Memory Device State Flags in Table 5-129 defines
    NVDIMM status as follows.  These bits indicate multiple info,
    such as failures, pending event, and capability.
    
      Bit [0] set to 1 to indicate that the previous SAVE to the
      Memory Device failed.
      Bit [1] set to 1 to indicate that the last RESTORE from the
      Memory Device failed.
      Bit [2] set to 1 to indicate that platform flush of data to
      Memory Device failed. As a result, the restored data content
      may be inconsistent even if SAVE and RESTORE do not indicate
      failure.
      Bit [3] set to 1 to indicate that the Memory Device is observed
      to be not armed prior to OSPM hand off. A Memory Device is
      considered armed if it is able to accept persistent writes.
      Bit [4] set to 1 to indicate that the Memory Device observed
      SMART and health events prior to OSPM handoff.
    
    /sys/bus/nd/devices/nmemX/nfit/flags shows this flags info.
    The output strings associated with the bits are "save", "restore",
    "smart", etc., which can be confusing as they may be interpreted
    as positive status, i.e. save succeeded.
    
    Change also the dev_info() message in acpi_nfit_register_dimms()
    to be consistent with the sysfs flags strings.
    
    Reported-by: Robert Elliott <elliott@xxxxxx>
    Signed-off-by: Toshi Kani <toshi.kani@xxxxxx>
    [ross: rename 'not_arm' to 'not_armed']
    Cc: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
    [djbw: defer adding bit5, HEALTH_ENABLED, for now]
    Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>

diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index bb29e56276bd..cf0fd96a7602 100644
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -702,11 +702,11 @@ static ssize_t flags_show(struct device *dev,
 	u16 flags = to_nfit_memdev(dev)->flags;
 
 	return sprintf(buf, "%s%s%s%s%s\n",
-			flags & ACPI_NFIT_MEM_SAVE_FAILED ? "save " : "",
-			flags & ACPI_NFIT_MEM_RESTORE_FAILED ? "restore " : "",
-			flags & ACPI_NFIT_MEM_FLUSH_FAILED ? "flush " : "",
-			flags & ACPI_NFIT_MEM_ARMED ? "arm " : "",
-			flags & ACPI_NFIT_MEM_HEALTH_OBSERVED ? "smart " : "");
+		flags & ACPI_NFIT_MEM_SAVE_FAILED ? "save_fail " : "",
+		flags & ACPI_NFIT_MEM_RESTORE_FAILED ? "restore_fail " : "",
+		flags & ACPI_NFIT_MEM_FLUSH_FAILED ? "flush_fail " : "",
+		flags & ACPI_NFIT_MEM_ARMED ? "not_armed " : "",
+		flags & ACPI_NFIT_MEM_HEALTH_OBSERVED ? "smart_event " : "");
 }
 static DEVICE_ATTR_RO(flags);
 
@@ -849,12 +849,12 @@ static int acpi_nfit_register_dimms(struct acpi_nfit_desc *acpi_desc)
 		if ((mem_flags & ACPI_NFIT_MEM_FAILED_MASK) == 0)
 			continue;
 
-		dev_info(acpi_desc->dev, "%s: failed: %s%s%s%s\n",
+		dev_info(acpi_desc->dev, "%s flags:%s%s%s%s\n",
 				nvdimm_name(nvdimm),
-			mem_flags & ACPI_NFIT_MEM_SAVE_FAILED ? "save " : "",
-			mem_flags & ACPI_NFIT_MEM_RESTORE_FAILED ? "restore " : "",
-			mem_flags & ACPI_NFIT_MEM_FLUSH_FAILED ? "flush " : "",
-			mem_flags & ACPI_NFIT_MEM_ARMED ? "arm " : "");
+		  mem_flags & ACPI_NFIT_MEM_SAVE_FAILED ? " save_fail" : "",
+		  mem_flags & ACPI_NFIT_MEM_RESTORE_FAILED ? " restore_fail":"",
+		  mem_flags & ACPI_NFIT_MEM_FLUSH_FAILED ? " flush_fail" : "",
+		  mem_flags & ACPI_NFIT_MEM_ARMED ? " not_armed" : "");
 
 	}