linux-toradex.git/drivers/nvdimm/pfn_devs.c, branch v5.10-rc6

mm/memremap_pages: support multiple ranges per invocation

2020-10-14T01:38:28+00:00

In support of device-dax growing the ability to front physically
dis-contiguous ranges of memory, update devm_memremap_pages() to track
multiple ranges with a single reference counter and devm instance.

Convert all [devm_]memremap_pages() users to specify the number of ranges
they are mapping in their 'struct dev_pagemap' instance.

Signed-off-by: Dan Williams 
Signed-off-by: Andrew Morton 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Benjamin Herrenschmidt 
Cc: Vishal Verma 
Cc: Vivek Goyal 
Cc: Dave Jiang 
Cc: Ben Skeggs 
Cc: David Airlie 
Cc: Daniel Vetter 
Cc: Ira Weiny 
Cc: Bjorn Helgaas 
Cc: Boris Ostrovsky 
Cc: Juergen Gross 
Cc: Stefano Stabellini 
Cc: "Jérôme Glisse" 
Cc: Ard Biesheuvel 
Cc: Ard Biesheuvel 
Cc: Borislav Petkov 
Cc: Brice Goglin 
Cc: Catalin Marinas 
Cc: Dave Hansen 
Cc: David Hildenbrand 
Cc: Greg Kroah-Hartman 
Cc: "H. Peter Anvin" 
Cc: Hulk Robot 
Cc: Ingo Molnar 
Cc: Jason Gunthorpe 
Cc: Jason Yan 
Cc: Jeff Moyer 
Cc: "Jérôme Glisse" 
Cc: Jia He 
Cc: Joao Martins 
Cc: Jonathan Cameron 
Cc: kernel test robot 
Cc: Mike Rapoport 
Cc: Pavel Tatashin 
Cc: Peter Zijlstra 
Cc: "Rafael J. Wysocki" 
Cc: Randy Dunlap 
Cc: Thomas Gleixner 
Cc: Tom Lendacky 
Cc: Wei Yang 
Cc: Will Deacon 
Link: https://lkml.kernel.org/r/159643103789.4062302.18426128170217903785.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/160106116293.30709.13350662794915396198.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds

mm/memremap_pages: convert to 'struct range'

2020-10-14T01:38:28+00:00

The 'struct resource' in 'struct dev_pagemap' is only used for holding
resource span information.  The other fields, 'name', 'flags', 'desc',
'parent', 'sibling', and 'child' are all unused wasted space.

This is in preparation for introducing a multi-range extension of
devm_memremap_pages().

The bulk of this change is unwinding all the places internal to libnvdimm
that used 'struct resource' unnecessarily, and replacing instances of
'struct dev_pagemap'.res with 'struct dev_pagemap'.range.

P2PDMA had a minor usage of the resource flags field, but only to report
failures with "%pR".  That is replaced with an open coded print of the
range.

[dan.carpenter@oracle.com: mm/hmm/test: use after free in dmirror_allocate_chunk()]
  Link: https://lkml.kernel.org/r/20200926121402.GA7467@kadam

Signed-off-by: Dan Williams 
Signed-off-by: Dan Carpenter 
Signed-off-by: Andrew Morton 
Reviewed-by: Boris Ostrovsky 	[xen]
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Benjamin Herrenschmidt 
Cc: Vishal Verma 
Cc: Vivek Goyal 
Cc: Dave Jiang 
Cc: Ben Skeggs 
Cc: David Airlie 
Cc: Daniel Vetter 
Cc: Ira Weiny 
Cc: Bjorn Helgaas 
Cc: Juergen Gross 
Cc: Stefano Stabellini 
Cc: "Jérôme Glisse" 
Cc: Andy Lutomirski 
Cc: Ard Biesheuvel 
Cc: Ard Biesheuvel 
Cc: Borislav Petkov 
Cc: Brice Goglin 
Cc: Catalin Marinas 
Cc: Dave Hansen 
Cc: David Hildenbrand 
Cc: Greg Kroah-Hartman 
Cc: "H. Peter Anvin" 
Cc: Hulk Robot 
Cc: Ingo Molnar 
Cc: Jason Gunthorpe 
Cc: Jason Yan 
Cc: Jeff Moyer 
Cc: Jia He 
Cc: Joao Martins 
Cc: Jonathan Cameron 
Cc: kernel test robot 
Cc: Mike Rapoport 
Cc: Pavel Tatashin 
Cc: Peter Zijlstra 
Cc: "Rafael J. Wysocki" 
Cc: Randy Dunlap 
Cc: Thomas Gleixner 
Cc: Tom Lendacky 
Cc: Wei Yang 
Cc: Will Deacon 
Link: https://lkml.kernel.org/r/159643103173.4062302.768998885691711532.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/160106115761.30709.13539840236873663620.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds

libnvdimm: Convert to DEVICE_ATTR_ADMIN_RO()

2020-07-28T18:21:10+00:00

Move libnvdimm sysfs attributes that currently use an open coded
DEVICE_ATTR() to hide sensitive root-only information (physical memory
layout) to the new DEVICE_ATTR_ADMIN_RO() helper.

Cc: Vishal Verma 
Cc: Dave Jiang 
Cc: Ira Weiny 
Signed-off-by: Dan Williams 
Signed-off-by: Vishal Verma

libnvdimm/namespace: Enforce memremap_compat_align()

2020-03-17T19:23:21+00:00

The pmem driver on PowerPC crashes with the following signature when
instantiating misaligned namespaces that map their capacity via
memremap_pages().

    BUG: Unable to handle kernel data access at 0xc001000406000000
    Faulting instruction address: 0xc000000000090790
    NIP [c000000000090790] arch_add_memory+0xc0/0x130
    LR [c000000000090744] arch_add_memory+0x74/0x130
    Call Trace:
     arch_add_memory+0x74/0x130 (unreliable)
     memremap_pages+0x74c/0xa30
     devm_memremap_pages+0x3c/0xa0
     pmem_attach_disk+0x188/0x770
     nvdimm_bus_probe+0xd8/0x470

With the assumption that only memremap_pages() has alignment
constraints, enforce memremap_compat_align() for
pmem_should_map_pages(), nd_pfn, and nd_dax cases. This includes
preventing the creation of namespaces where the base address is
misaligned and cases there infoblock padding parameters are invalid.

Reported-by: Aneesh Kumar K.V 
Cc: Jeff Moyer 
Fixes: a3619190d62e ("libnvdimm/pfn: stop padding pmem namespaces to section alignment")
Reviewed-by: Aneesh Kumar K.V 
Signed-off-by: Dan Williams

libnvdimm/pfn: Prevent raw mode fallback if pfn-infoblock valid

2020-03-17T19:23:21+00:00

The EOPNOTSUPP return code from the pmem driver indicates that the
namespace has a configuration that may be valid, but the current kernel
does not support it. Expand this to all of the nd_pfn_validate() error
conditions after the infoblock has been verified as self consistent.

This prevents exposing the namespace to I/O when the infoblock needs to
be corrected, or the system needs to be put into a different
configuration (like changing the page size on PowerPC).

Cc: Aneesh Kumar K.V 
Cc: Jeff Moyer 
Reviewed-by: Aneesh Kumar K.V 
Signed-off-by: Dan Williams

mm/memremap_pages: Introduce memremap_compat_align()

2020-02-21T00:58:55+00:00

The "sub-section memory hotplug" facility allows memremap_pages() users
like libnvdimm to compensate for hardware platforms like x86 that have a
section size larger than their hardware memory mapping granularity.  The
compensation that sub-section support affords is being tolerant of
physical memory resources shifting by units smaller (64MiB on x86) than
the memory-hotplug section size (128 MiB). Where the platform
physical-memory mapping granularity is limited by the number and
capability of address-decode-registers in the memory controller.

While the sub-section support allows memremap_pages() to operate on
sub-section (2MiB) granularity, the Power architecture may still
require 16MiB alignment on "!radix_enabled()" platforms.

In order for libnvdimm to be able to detect and manage this per-arch
limitation, introduce memremap_compat_align() as a common minimum
alignment across all driver-facing memory-mapping interfaces, and let
Power override it to 16MiB in the "!radix_enabled()" case.

The assumption / requirement for 16MiB to be a viable
memremap_compat_align() value is that Power does not have platforms
where its equivalent of address-decode-registers never hardware remaps a
persistent memory resource on smaller than 16MiB boundaries. Note that I
tried my best to not add a new Kconfig symbol, but header include
entanglements defeated the #ifndef memremap_compat_align design pattern
and the need to export it defeats the __weak design pattern for arch
overrides.

Based on an initial patch by Aneesh.

Link: http://lore.kernel.org/r/CAPcyv4gBGNP95APYaBcsocEa50tQj9b5h__83vgngjq3ouGX_Q@mail.gmail.com
Reported-by: Aneesh Kumar K.V 
Reported-by: Jeff Moyer 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Reviewed-by: Aneesh Kumar K.V 
Acked-by: Michael Ellerman  (powerpc)
Signed-off-by: Dan Williams

libnvdimm: Simplify root read-only definition for the 'resource' attribute

2019-11-19T17:52:12+00:00

Rather than update the permission in ->is_visible() set the permission
directly at declaration time.

Cc: Ira Weiny 
Cc: Vishal Verma 
Signed-off-by: Dan Williams 
Reviewed-by: Aneesh Kumar K.V 
Link: https://lore.kernel.org/r/157309905534.1582359.13927459228885931097.stgit@dwillia2-desk3.amr.corp.intel.com

libnvdimm: Move attribute groups to device type

2019-11-17T17:17:38+00:00

Statically initialize the attribute groups for each libnvdimm
device_type. This is a preparation step for removing unnecessary exports
of attributes that can be included in the device_type by default.

Also take the opportunity to mark 'struct device_type' instances const.

Cc: Ira Weiny 
Cc: Vishal Verma 
Signed-off-by: Dan Williams 
Reviewed-by: Aneesh Kumar K.V 
Link: https://lore.kernel.org/r/157309900111.1582359.2445687530383470348.stgit@dwillia2-desk3.amr.corp.intel.com

libnvdimm/namespace: Differentiate between probe mapping and runtime mapping

2019-11-15T03:08:47+00:00

The nvdimm core currently maps the full namespace to an ioremap range
while probing the namespace mode. This can result in probe failures on
architectures that have limited ioremap space.

For example, with a large btt namespace that consumes most of I/O remap
range, depending on the sequence of namespace initialization, the user
can find a pfn namespace initialization failure due to unavailable I/O
remap space which nvdimm core uses for temporary mapping.

nvdimm core can avoid this failure by only mapping the reserved info
block area to check for pfn superblock type and map the full namespace
resource only before using the namespace.

Given that personalities like BTT can be layered on top of any namespace
type create a generic form of devm_nsio_enable (devm_namespace_enable)
and use it inside the per-personality attach routines. Now
devm_namespace_enable() is always paired with disable unless the mapping
is going to be used for long term runtime access.

Signed-off-by: Aneesh Kumar K.V 
Link: https://lore.kernel.org/r/20191017073308.32645-1-aneesh.kumar@linux.ibm.com
[djbw: reworks to move devm_namespace_{en,dis}able into *attach helpers]
Reported-by: kbuild test robot 
Link: https://lore.kernel.org/r/20191031105741.102793-2-aneesh.kumar@linux.ibm.com
Signed-off-by: Dan Williams

libnvdimm/pfn_dev: Don't clear device memmap area during generic namespace probe

2019-11-15T03:08:47+00:00

nvdimm core use nd_pfn_validate when looking for devdax or fsdax namespace. In this
case device resources are allocated against nd_namespace_io dev. In-order to
allow remap of range in nd_pfn_clear_memmap_error(), move the device memmap
area clearing while initializing pfn namespace. With this device
resource are allocated against nd_pfn and we can use nd_pfn->dev for remapping.

This also avoids calling nd_pfn_clear_mmap_errors twice. Once while probing the
namespace and second while initializing a pfn namespace.

Signed-off-by: Aneesh Kumar K.V 
Link: https://lore.kernel.org/r/20191101032728.113001-1-aneesh.kumar@linux.ibm.com
Signed-off-by: Dan Williams