queue-5.0/libnvdimm-pmem-honor-force_raw-for-legacy-pmem-regions.patch

   1 From fa7d2e639cd90442d868dfc6ca1d4cc9d8bf206e Mon Sep 17 00:00:00 2001
   2 From: Dan Williams <dan.j.williams@intel.com>
   3 Date: Thu, 24 Jan 2019 17:33:06 -0800
   4 Subject: libnvdimm/pmem: Honor force_raw for legacy pmem regions
   5
   6 From: Dan Williams <dan.j.williams@intel.com>
   7
   8 commit fa7d2e639cd90442d868dfc6ca1d4cc9d8bf206e upstream.
   9
  10 For recovery, where non-dax access is needed to a given physical address
  11 range, and testing, allow the 'force_raw' attribute to override the
  12 default establishment of a dev_pagemap.
  13
  14 Otherwise without this capability it is possible to end up with a
  15 namespace that can not be activated due to corrupted info-block, and one
  16 that can not be repaired due to a section collision.
  17
  18 Cc: <stable@vger.kernel.org>
  19 Fixes: 004f1afbe199 ("libnvdimm, pmem: direct map legacy pmem by default")
  20 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
  21 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  22
  23 ---
  24  drivers/nvdimm/namespace_devs.c |    4 ++++
  25  1 file changed, 4 insertions(+)
  26
  27 --- a/drivers/nvdimm/namespace_devs.c
  28 +++ b/drivers/nvdimm/namespace_devs.c
  29 @@ -138,6 +138,7 @@ bool nd_is_uuid_unique(struct device *de
  30  bool pmem_should_map_pages(struct device *dev)
  31  {
  32         struct nd_region *nd_region = to_nd_region(dev->parent);
  33 +       struct nd_namespace_common *ndns = to_ndns(dev);
  34         struct nd_namespace_io *nsio;
  35
  36         if (!IS_ENABLED(CONFIG_ZONE_DEVICE))
  37 @@ -149,6 +150,9 @@ bool pmem_should_map_pages(struct device
  38         if (is_nd_pfn(dev) || is_nd_btt(dev))
  39                 return false;
  40
  41 +       if (ndns->force_raw)
  42 +               return false;
  43 +
  44         nsio = to_nd_namespace_io(dev);
  45         if (region_intersects(nsio->res.start, resource_size(&nsio->res),
  46                                 IORESOURCE_SYSTEM_RAM,