In case performance stats for an nvdimm are not available, reading the
'perf_stats' sysfs file returns an -ENOENT error. A better approach is
to make the 'perf_stats' file entirely invisible to indicate that
performance stats for an nvdimm are unavailable.

So this patch updates 'papr_nd_attribute_group' to add a 'is_visible'
callback implemented as newly introduced 'papr_nd_attribute_visible()'
that returns an appropriate mode in case performance stats aren't
supported in a given nvdimm.

Also the initialization of 'papr_scm_priv.stat_buffer_len' is moved
from papr_scm_nvdimm_init() to papr_scm_probe() so that it value is
available when 'papr_nd_attribute_visible()' is called during nvdimm
initialization.

Even though 'perf_stats' attribute is available since v5.9, there are
no known user-space tools/scripts that are dependent on presence of its
sysfs file. Hence I dont expect any user-space breakage with this
patch.

Fixes: 2d02bf83 ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP")
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210513092349.285021-1-vaibhav@linux.ibm.com

Parse to and export from UUID own type, before dereferencing.
This also fixes wrong comment (Little Endian UUID is something else)
and should eliminate the direct strict types assignments.

Fixes: 43001c52 ("powerpc/papr_scm: Use ibm,unit-guid as the iset cookie")
Fixes: 259a948c ("powerpc/pseries/scm: Use a specific endian format for storing uuid from the device tree")
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210616134303.58185-1-andriy.shevchenko@linux.intel.com

Currently drc_pmem_qeury_stats() generates a dev_err in case
"Enable Performance Information Collection" feature is disabled from
HMC or performance stats are not available for an nvdimm. The error is
of the form below:

papr_scm ibm,persistent-memory:ibm,pmemory@44104001: Failed to query
	 performance stats, Err:-10

This error message confuses users as it implies a possible problem
with the nvdimm even though its due to a disabled/unavailable
feature. We fix this by explicitly handling the H_AUTHORITY and
H_UNSUPPORTED errors from the H_SCM_PERFORMANCE_STATS hcall.

In case of H_AUTHORITY error an info message is logged instead of an
error, saying that "Permission denied while accessing performance
stats" and an EPERM error is returned back.

In case of H_UNSUPPORTED error we return a EOPNOTSUPP error back from
drc_pmem_query_stats() indicating that performance stats-query
operation is not supported on this nvdimm.

Fixes: 2d02bf83 ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP")
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210508043642.114076-1-vaibhav@linux.ibm.com

In case an nvdimm is found to be unarmed during probe then set its
NDD_UNARMED flag before nvdimm_create(). This would enforce a
read-only access to the ndimm region. Presently even if an nvdimm is
unarmed its not marked as read-only on ppc64 guests.

The patch updates papr_scm_nvdimm_init() to force query of nvdimm
health via __drc_pmem_query_health() and if nvdimm is found to be
unarmed then set the nvdimm flag ND_UNARMED for nvdimm_create().
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210329113103.476760-1-vaibhav@linux.ibm.com

When I changed the rc variable to be long rather than int64_t I
neglected to update the printk(), leading to a build break:

  arch/powerpc/platforms/pseries/papr_scm.c: In function 'papr_scm_pmem_flush':
  arch/powerpc/platforms/pseries/papr_scm.c:144:26: warning: format
    '%lld' expects argument of type 'long long int', but argument 3 has
    type 'long int' [-Wformat=]

Fixes: 75b7c05e ("powerpc/papr_scm: Implement support for H_SCM_FLUSH hcall")
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210416111209.765444-2-mpe@ellerman.id.au

Add support for ND_REGION_ASYNC capability if the device tree
indicates 'ibm,hcall-flush-required' property in the NVDIMM node.
Flush is done by issuing H_SCM_FLUSH hcall to the hypervisor.

If the flush request failed, the hypervisor is expected to
to reflect the problem in the subsequent nvdimm H_SCM_HEALTH call.

This patch prevents mmap of namespaces with MAP_SYNC flag if the
nvdimm requires an explicit flush[1].

References:
[1] https://github.com/avocado-framework-tests/avocado-misc-tests/blob/master/memory/ndctl.py.data/map_sync.cSigned-off-by: NShivaprasad G Bhat <sbhat@linux.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Use unsigned long / long instead of uint64_t/int64_t]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/161703936121.36.7260632399582101498.stgit@e1fbed493c87

Add NVDIMM_FAMILY_PAPR to the list of valid 'dimm_family_mask'
acceptable by papr_scm. This is needed as since commit
92fe2aa8 ("libnvdimm: Validate command family indices") libnvdimm
performs a validation of 'nd_cmd_pkg.nd_family' received as part of
ND_CMD_CALL processing to ensure only known command families can use
the general ND_CMD_CALL pass-through functionality.

Without this change the ND_CMD_CALL pass-through targeting
NVDIMM_FAMILY_PAPR error out with -EINVAL.

Fixes: 92fe2aa8 ("libnvdimm: Validate command family indices")
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200913211904.24472-1-vaibhav@linux.ibm.com

Build the kernel with 'make C=2':
arch/powerpc/platforms/pseries/papr_scm.c:825:1: warning: symbol
'dev_attr_perf_stats' was not declared. Should it be static?
Signed-off-by: NWang Wensheng <wangwensheng4@huawei.com>
Reviewed-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200918085951.44983-1-wangwensheng4@huawei.com

A warning is reported by the kernel in case perf_stats_show() returns
an error code. The warning is of the form below:

 papr_scm ibm,persistent-memory:ibm,pmemory@44100001:
 	  Failed to query performance stats, Err:-10
 dev_attr_show: perf_stats_show+0x0/0x1c0 [papr_scm] returned bad count
 fill_read_buffer: dev_attr_show+0x0/0xb0 returned bad count

On investigation it looks like that the compiler is silently
truncating the return value of drc_pmem_query_stats() from 'long' to
'int', since the variable used to store the return code 'rc' is an
'int'. This truncated value is then returned back as a 'ssize_t' back
from perf_stats_show() to 'dev_attr_show()' which thinks of it as a
large unsigned number and triggers this warning..

To fix this we update the type of variable 'rc' from 'int' to
'ssize_t' that prevents the compiler from truncating the return value
of drc_pmem_query_stats() and returning correct signed value back from
perf_stats_show().

Fixes: 2d02bf83 ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP")
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200912081451.66225-1-vaibhav@linux.ibm.com

The newly introduced 'perf_stats' attribute uses the default access
mode of 0444, allowing non-root users to access performance stats of
an nvdimm and potentially force the kernel into issuing a large number
of expensive hypercalls. Since the information exposed by this
attribute cannot be cached it is better to ward off access to this
attribute from users who don't need to access to these performance
statistics.

Hence update the access mode of 'perf_stats' attribute to be only
readable by root users.

Fixes: 2d02bf83 ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP")
Reported-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200907110540.21349-1-vaibhav@linux.ibm.com

We add support for reporting 'fuel-gauge' NVDIMM metric via
PAPR_PDSM_HEALTH pdsm payload. 'fuel-gauge' metric indicates the usage
life remaining of a papr-scm compatible NVDIMM. PHYP exposes this
metric via the H_SCM_PERFORMANCE_STATS.

The metric value is returned from the pdsm by extending the return
payload 'struct nd_papr_pdsm_health' without breaking the ABI. A new
field 'dimm_fuel_gauge' to hold the metric value is introduced at the
end of the payload struct and its presence is indicated by by
extension flag PDSM_DIMM_HEALTH_RUN_GAUGE_VALID.

The patch introduces a new function papr_pdsm_fuel_gauge() that is
called from papr_pdsm_health(). If fetching NVDIMM performance stats
is supported then 'papr_pdsm_fuel_gauge()' allocated an output buffer
large enough to hold the performance stat and passes it to
drc_pmem_query_stats() that issues the HCALL to PHYP. The return value
of the stat is then populated in the 'struct
nd_papr_pdsm_health.dimm_fuel_gauge' field with extension flag
'PDSM_DIMM_HEALTH_RUN_GAUGE_VALID' set in 'struct
nd_papr_pdsm_health.extension_flags'
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200731064153.182203-3-vaibhav@linux.ibm.com

Update papr_scm.c to query dimm performance statistics from PHYP via
H_SCM_PERFORMANCE_STATS hcall and export them to user-space as PAPR
specific NVDIMM attribute 'perf_stats' in sysfs. The patch also
provide a sysfs ABI documentation for the stats being reported and
their meanings.

During NVDIMM probe time in papr_scm_nvdimm_init() a special variant
of H_SCM_PERFORMANCE_STATS hcall is issued to check if collection of
performance statistics is supported or not. If successful then a PHYP
returns a maximum possible buffer length needed to read all
performance stats. This returned value is stored in a per-nvdimm
attribute 'stat_buffer_len'.

The layout of request buffer for reading NVDIMM performance stats from
PHYP is defined in 'struct papr_scm_perf_stats' and 'struct
papr_scm_perf_stat'. These structs are used in newly introduced
drc_pmem_query_stats() that issues the H_SCM_PERFORMANCE_STATS hcall.

The sysfs access function perf_stats_show() uses value
'stat_buffer_len' to allocate a buffer large enough to hold all
possible NVDIMM performance stats and passes it to
drc_pmem_query_stats() to populate. Finally statistics reported in the
buffer are formatted into the sysfs access function output buffer.
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200731064153.182203-2-vaibhav@linux.ibm.com

The sparse tool complains as follows:

arch/powerpc/platforms/pseries/papr_scm.c:97:1: warning:
 symbol 'papr_nd_regions' was not declared. Should it be static?
arch/powerpc/platforms/pseries/papr_scm.c:98:1: warning:
 symbol 'papr_ndr_lock' was not declared. Should it be static?

Those variables are not used outside of papr_scm.c, so this
commit marks them static.

Fixes: 85343a8d ("powerpc/papr/scm: Add bad memory ranges to nvdimm bad ranges")
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200725091949.75234-1-weiyongjun1@huawei.com

Subscribe to the MCE notification and add the physical address which
generated a memory error to nvdimm bad range.
Signed-off-by: NSantosh Sivaraj <santosh@fossix.org>
Reviewed-by: NMahesh Salgaonkar <mahesh@linux.ibm.com>
Reviewed-by: NChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709135142.721504-2-santosh@fossix.org

With kernel now supporting new pmem flush/sync instructions, we can now
enable the kernel to initialize the device. On P10 these devices would
appear with a new compatible string. For PAPR device we have

compatible       "ibm,pmemory-v2"

and for OF pmem device we have

compatible       "pmem-region-v2"
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200701072235.223558-8-aneesh.kumar@linux.ibm.com

This patch implements support for PDSM request 'PAPR_PDSM_HEALTH'
that returns a newly introduced 'struct nd_papr_pdsm_health' instance
containing dimm health information back to user space in response to
ND_CMD_CALL. This functionality is implemented in newly introduced
papr_pdsm_health() that queries the nvdimm health information and
then copies this information to the package payload whose layout is
defined by 'struct nd_papr_pdsm_health'.
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20200615124407.32596-7-vaibhav@linux.ibm.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

Introduce support for PAPR NVDIMM Specific Methods (PDSM) in papr_scm
module and add the command family NVDIMM_FAMILY_PAPR to the white list
of NVDIMM command sets. Also advertise support for ND_CMD_CALL for the
nvdimm command mask and implement necessary scaffolding in the module
to handle ND_CMD_CALL ioctl and PDSM requests that we receive.

The layout of the PDSM request as we expect from libnvdimm/libndctl is
described in newly introduced uapi header 'papr_pdsm.h' which
defines a 'struct nd_pkg_pdsm' and a maximal union named
'nd_pdsm_payload'. These new structs together with 'struct nd_cmd_pkg'
for a pdsm envelop thats sent by libndctl to libnvdimm and serviced by
papr_scm in 'papr_scm_service_pdsm()'. The PDSM request is
communicated by member 'struct nd_cmd_pkg.nd_command' together with
other information on the pdsm payload (size-in, size-out).

The patch also introduces 'struct pdsm_cmd_desc' instances of which
are stored in an array __pdsm_cmd_descriptors[] indexed with PDSM cmd
and corresponding access function pdsm_cmd_desc() is
introduced. 'struct pdsm_cdm_desc' holds the service function for a
given PDSM and corresponding payload in/out sizes.

A new function papr_scm_service_pdsm() is introduced and is called from
papr_scm_ndctl() in case of a PDSM request is received via ND_CMD_CALL
command from libnvdimm. The function performs validation on the PDSM
payload based on info present in corresponding PDSM descriptor and if
valid calls the 'struct pdcm_cmd_desc.service' function to service the
PDSM.
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20200615124407.32596-6-vaibhav@linux.ibm.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

Since papr_scm_ndctl() can be called from outside papr_scm, its
exposed to the possibility of receiving NULL as value of 'cmd_rc'
argument. This patch updates papr_scm_ndctl() to protect against such
possibility by assigning it pointer to a local variable in case cmd_rc
== NULL.

Finally the patch also updates the 'default' add a debug log unknown
'cmd' values.
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20200615124407.32596-5-vaibhav@linux.ibm.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

Implement support for fetching nvdimm health information via
H_SCM_HEALTH hcall as documented in Ref[1]. The hcall returns a pair
of 64-bit bitmap, bitwise-and of which is then stored in
'struct papr_scm_priv' and subsequently partially exposed to
user-space via newly introduced dimm specific attribute
'papr/flags'. Since the hcall is costly, the health information is
cached and only re-queried, 60s after the previous successful hcall.

The patch also adds a  documentation text describing flags reported by
the the new sysfs attribute 'papr/flags' is also introduced at
Documentation/ABI/testing/sysfs-bus-papr-pmem.

[1] commit 58b278f5 ("powerpc: Provide initial documentation for
PAPR hcalls")
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20200615124407.32596-4-vaibhav@linux.ibm.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

Currently, kernel shows the below values
	"persistence_domain":"cpu_cache"
	"persistence_domain":"memory_controller"
	"persistence_domain":"unknown"

"cpu_cache" indicates no extra instructions is needed to ensure the persistence
of data in the pmem media on power failure.

"memory_controller" indicates cpu cache flush instructions are required to flush
the data. Platform provides mechanisms to automatically flush outstanding
write data from memory controler to pmem on system power loss.

Based on the above use memory_controller for non volatile regions on ppc64.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/20200324034821.60869-1-aneesh.kumar@linux.ibm.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

The NDD_ALIASING flag is used to indicate where pmem capacity might
alias with blk capacity and require labeling. It is also used to
indicate whether the DIMM supports labeling. Separate this latter
capability into its own flag so that the NDD_ALIASING flag is scoped to
true aliased configurations.

To my knowledge aliased configurations only exist in the ACPI spec,
there are no known platforms that ship this support in production.

This clarity allows namespace-capacity alignment constraints around
interleave-ways to be relaxed.

Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: NJeff Moyer <jmoyer@redhat.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/158041477856.3889308.4212605617834097674.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

Function papr_scm_ndctl() is neither exported from the module nor
called directly from outside 'papr.c' hence should be marked 'static'.
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200130040206.79998-1-vaibhav@linux.ibm.com

Now that the core exports numa_map_to_online_node() switch to that
instead of the locally coded duplicate.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
Reported-by: N"Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157401276263.43284.12616818803654229788.stgit@dwillia2-desk3.amr.corp.intel.comReviewed-by: NIngo Molnar <mingo@kernel.org>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/158188325830.894464.9454884523846454529.stgit@dwillia2-desk3.amr.corp.intel.com

String 'bus_desc.provider_name' allocated inside
papr_scm_nvdimm_init() will leaks in case call to
nvdimm_bus_register() fails or when papr_scm_remove() is called.

This minor patch ensures that 'bus_desc.provider_name' is freed in
error path for nvdimm_bus_register() as well as in papr_scm_remove().

Fixes: b5beae5e ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200122155140.120429-1-vaibhav@linux.ibm.com

Setting ND_REGION_PAGEMAP flag implies namespace mode defaults to fsdax mode.
This also means kernel ends up creating struct page backing for these namspace
ranges. With large namespaces that is not the right thing to do. We
should let the user select the mode he/she wants the namespace to be created
with.

Hence disable ND_REGION_PAGEMAP for papr_scm regions. We still keep the flag for
of_pmem because it supports only small persistent memory regions.

This is similar to what is done for x86 with commit
commit: 004f1afb ("libnvdimm, pmem: direct map legacy pmem by default")
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200108064647.169637-1-aneesh.kumar@linux.ibm.com

Resource struct p->res is assigned later. Avoid using %pR before the resource
struct is assigned.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191202063855.154321-1-aneesh.kumar@linux.ibm.com

A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nvdimm_bus_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309903815.1582359.6418211876315050283.stgit@dwillia2-desk3.amr.corp.intel.com

A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nvdimm_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309903201.1582359.10966209746585062329.stgit@dwillia2-desk3.amr.corp.intel.com

A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_mapping_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309902686.1582359.6749533709859492704.stgit@dwillia2-desk3.amr.corp.intel.com

A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_region_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309902169.1582359.16828508538444551337.stgit@dwillia2-desk3.amr.corp.intel.com

A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_numa_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157401269537.43284.14411189404186877352.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_device_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

For regions this creates a new nd_region_attribute_groups[] added to the
per-region device-type instances.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309901138.1582359.12909354140826530394.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>

Remove .owner field if calls are used which set it automatically
Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190218133950.95225-1-yuehaibing@huawei.com

A validation check to prevent out of bounds read/write inside
functions papr_scm_meta_{get,set}() is off-by-one that prevent reads
and writes to the last byte of the label area.

This bug manifests as a failure to probe a dimm when libnvdimm is
unable to read the entire config-area as advertised by
ND_CMD_GET_CONFIG_SIZE. This usually happens when there are large
number of namespaces created in the region backed by the dimm and the
label-index spans max possible config-area. An error of the form below
usually reported in the kernel logs:

[  255.293912] nvdimm: probe of nmem0 failed with error -22

The patch fixes these validation checks there by letting libnvdimm
access the entire config-area.

Fixes: 53e80bd0('powerpc/nvdimm: Add support for multibyte read/write for metadata')
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190927062002.3169-1-vaibhav@linux.ibm.com

Right now we force an unbind of SCM memory at drcindex on H_OVERLAP error.
This really slows down operations like kexec where we get the H_OVERLAP
error because we don't go through a full hypervisor re init.

H_OVERLAP error for a H_SCM_BIND_MEM hcall indicates that SCM memory at
drc index is already bound. Since we don't specify a logical memory
address for bind hcall, we can use the H_SCM_QUERY hcall to query
the already bound logical address.

Boot time difference with and without patch is:

[    5.583617] IOMMU table initialized, virtual merging enabled
[    5.603041] papr_scm ibm,persistent-memory:ibm,pmemory@44104001: Retrying bind after unbinding
[  301.514221] papr_scm ibm,persistent-memory:ibm,pmemory@44108001: Retrying bind after unbinding
[  340.057238] hv-24x7: read 1530 catalog entries, created 537 event attrs (0 failures), 275 descs

after fix

[    5.101572] IOMMU table initialized, virtual merging enabled
[    5.116984] papr_scm ibm,persistent-memory:ibm,pmemory@44104001: Querying SCM details
[    5.117223] papr_scm ibm,persistent-memory:ibm,pmemory@44108001: Querying SCM details
[    5.120530] hv-24x7: read 1530 catalog entries, created 537 event attrs (0 failures), 275 descs
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903123452.28620-2-aneesh.kumar@linux.ibm.com

This simplifies the error handling and also enable us to switch to
H_SCM_QUERY hcall in a later patch on H_OVERLAP error.

We also do some kernel print formatting fixup in this patch.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903123452.28620-1-aneesh.kumar@linux.ibm.com

Currently, nvdimm subsystem expects the device numa node for SCM device to be
an online node. It also doesn't try to bring the device numa node online. Hence
if we use a non-online numa node as device node we hit crashes like below. This
is because we try to access uninitialized NODE_DATA in different code paths.

cpu 0x0: Vector: 300 (Data Access) at [c0000000fac53170]
    pc: c0000000004bbc50: ___slab_alloc+0x120/0xca0
    lr: c0000000004bc834: __slab_alloc+0x64/0xc0
    sp: c0000000fac53400
   msr: 8000000002009033
   dar: 73e8
 dsisr: 80000
  current = 0xc0000000fabb6d80
  paca    = 0xc000000003870000   irqmask: 0x03   irq_happened: 0x01
    pid   = 7, comm = kworker/u16:0
Linux version 5.2.0-06234-g76bd729b2644 (kvaneesh@ltc-boston123) (gcc version 7.4.0 (Ubuntu 7.4.0-1ubuntu1~18.04.1)) #135 SMP Thu Jul 11 05:36:30 CDT 2019
enter ? for help
[link register   ] c0000000004bc834 __slab_alloc+0x64/0xc0
[c0000000fac53400] c0000000fac53480 (unreliable)
[c0000000fac53500] c0000000004bc818 __slab_alloc+0x48/0xc0
[c0000000fac53560] c0000000004c30a0 __kmalloc_node_track_caller+0x3c0/0x6b0
[c0000000fac535d0] c000000000cfafe4 devm_kmalloc+0x74/0xc0
[c0000000fac53600] c000000000d69434 nd_region_activate+0x144/0x560
[c0000000fac536d0] c000000000d6b19c nd_region_probe+0x17c/0x370
[c0000000fac537b0] c000000000d6349c nvdimm_bus_probe+0x10c/0x230
[c0000000fac53840] c000000000cf3cc4 really_probe+0x254/0x4e0
[c0000000fac538d0] c000000000cf429c driver_probe_device+0x16c/0x1e0
[c0000000fac53950] c000000000cf0b44 bus_for_each_drv+0x94/0x130
[c0000000fac539b0] c000000000cf392c __device_attach+0xdc/0x200
[c0000000fac53a50] c000000000cf231c bus_probe_device+0x4c/0xf0
[c0000000fac53a90] c000000000ced268 device_add+0x528/0x810
[c0000000fac53b60] c000000000d62a58 nd_async_device_register+0x28/0xa0
[c0000000fac53bd0] c0000000001ccb8c async_run_entry_fn+0xcc/0x1f0
[c0000000fac53c50] c0000000001bcd9c process_one_work+0x46c/0x860
[c0000000fac53d20] c0000000001bd4f4 worker_thread+0x364/0x5f0
[c0000000fac53db0] c0000000001c7260 kthread+0x1b0/0x1c0
[c0000000fac53e20] c00000000000b954 ret_from_kernel_thread+0x5c/0x68

The patch tries to fix this by picking the nearest online node as the SCM node.
This does have a problem of us losing the information that SCM node is
equidistant from two other online nodes. If applications need to understand these
fine-grained details we should express then like x86 does via
/sys/devices/system/node/nodeX/accessY/initiators/

With the patch we get

 # numactl -H
available: 2 nodes (0-1)
node 0 cpus:
node 0 size: 0 MB
node 0 free: 0 MB
node 1 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
node 1 size: 130865 MB
node 1 free: 129130 MB
node distances:
node   0   1
  0:  10  20
  1:  20  10
 # cat /sys/bus/nd/devices/region0/numa_node
0
 # dmesg | grep papr_scm
[   91.332305] papr_scm ibm,persistent-memory:ibm,pmemory@44104001: Region registered with target node 2 and online node 0
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190729095128.23707-1-aneesh.kumar@linux.ibm.com

In some cases initial bind of scm memory for an lpar can fail if
previously it wasn't released using a scm-unbind hcall. This situation
can arise due to panic of the previous kernel or forced lpar
fadump. In such cases the H_SCM_BIND_MEM return a H_OVERLAP error.

To mitigate such cases the patch updates papr_scm_probe() to force a
call to drc_pmem_unbind() in case the initial bind of scm memory fails
with EBUSY error. In case scm-bind operation again fails after the
forced scm-unbind then we follow the existing error path. We also
update drc_pmem_bind() to handle the H_OVERLAP error returned by phyp
and indicate it as a EBUSY error back to the caller.
Suggested-by: N"Oliver O'Halloran" <oohall@gmail.com>
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: NOliver O'Halloran <oohall@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190629160610.23402-4-vaibhav@linux.ibm.com

The new hcall named H_SCM_UNBIND_ALL has been introduce that can
unbind all or specific scm memory assigned to an lpar. This is
more efficient than using H_SCM_UNBIND_MEM as currently we don't
support partial unbind of scm memory.

Hence this patch proposes following changes to drc_pmem_unbind():

    * Update drc_pmem_unbind() to replace hcall H_SCM_UNBIND_MEM to
      H_SCM_UNBIND_ALL.

    * Update drc_pmem_unbind() to handles cases when PHYP asks the guest
      kernel to wait for specific amount of time before retrying the
      hcall via the 'LONG_BUSY' return value.

    * Ensure appropriate error code is returned back from the function
      in case of an error.
Reviewed-by: NOliver O'Halloran <oohall@gmail.com>
Signed-off-by: NVaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190629160610.23402-3-vaibhav@linux.ibm.com

We used uuid_parse to convert uuid string from device tree to two u64
components. We want to make sure we look at the uuid read from device
tree in an endian-neutral fashion. For now, I am picking little-endian
to be format so that we don't end up doing an additional conversion.

The reason to store in a specific endian format is to enable reading
the namespace created with a little-endian kernel config on a
big-endian kernel. We do store the device tree uuid string as a 64-bit
little-endian cookie in the label area. When booting the kernel we
also compare this cookie against what is read from the device tree.
For this, to work we have to store and compare these values in a CPU
endian config independent fashion.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>