Commit Graph

22 Commits

Author SHA1 Message Date
Thomas Gleixner 5b497af42f treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of version 2 of the gnu general public license as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 64 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.894819585@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:38 +02:00
Aditya Pakki 486fa92df4 libnvdimm/btt: Fix a kmemdup failure check
In case kmemdup fails, the fix releases resources and returns to
avoid the NULL pointer dereference.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-03-27 10:08:55 -07:00
Vishal Verma 9dedc73a46 libnvdimm/btt: Fix LBA masking during 'free list' population
The Linux BTT implementation assumes that log entries will never have
the 'zero' flag set, and indeed it never sets that flag for log entries
itself.

However, the UEFI spec is ambiguous on the exact format of the LBA field
of a log entry, specifically as to whether it should include the
additional flag bits or not. While a zero bit doesn't make sense in the
context of a log entry, other BTT implementations might still have it set.

If an implementation does happen to have it set, we would happily read
it in as the next block to write to for writes. Since a high bit is set,
it pushes the block number out of the range of an 'arena', and we fail
such a write with an EIO.

Follow the robustness principle, and tolerate such implementations by
stripping out the zero flag when populating the free list during
initialization. Additionally, use the same stripped out entries for
detection of incomplete writes and map restoration that happens at this
stage.

Add a sysfs file 'log_zero_flags' that indicates the ability to accept
such a layout to userspace applications. This enables 'ndctl
check-namespace' to recognize whether the kernel is able to handle zero
flags, or whether it should attempt a fix-up under the --repair option.

Cc: Dan Williams <dan.j.williams@intel.com>
Reported-by: Dexuan Cui <decui@microsoft.com>
Reported-by: Pedro d'Aquino Filocre F S Barbuda <pbarbuda@microsoft.com>
Tested-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-28 09:57:39 -08:00
Dan Williams 426824d63b libnvdimm: remove redundant __func__ in dev_dbg
Dynamic debug can be instructed to add the function name to the debug
output using the +f switch, so there is no need for the libnvdimm
modules to do it again. If a user decides to add the +f switch for
libnvdimm's dynamic debug this results in double prints of the function
name.

Reported-by: Johannes Thumshirn <jthumshirn@suse.de>
Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-06 08:44:17 -08:00
Dan Williams b2c48f9f95 libnvdimm: rename nd_sector_size_{show,store} to nd_size_select_{show,store}
Prepare for other another consumer of this size selection scheme that is
not a 'sector size'.

Cc: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-11 17:36:54 -07:00
Vishal Verma 14e4945426 libnvdimm, btt: BTT updates for UEFI 2.7 format
The UEFI 2.7 specification defines an updated BTT metadata format,
bumping the revision to 2.0. Add support for the new format, while
retaining compatibility for the old 1.1 format.

Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Linda Knippers <linda.knippers@hpe.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-29 13:50:38 -07:00
Dan Williams b3fde74ea1 libnvdimm, label: add address abstraction identifiers
Starting with v1.2 labels, 'address abstractions' can be hinted via an
address abstraction id that implies an info-block format. The standard
address abstraction in the specification is the v2 format of the
Block-Translation-Table (BTT). Support for that is saved for a later
patch, for now we add support for the Linux supported address
abstractions BTT (v1), PFN, and DAX.

The new 'holder_class' attribute for namespace devices is added for
tooling to specify the 'abstraction_guid' to store in the namespace label.
For v1.1 labels this field is undefined and any setting of
'holder_class' away from the default 'none' value will only have effect
until the driver is unloaded. Setting 'holder_class' requires that
whatever device tries to claim the namespace must be of the specified
class.

Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15 14:31:40 -07:00
Christoph Hellwig ef40dda5bb uuid: hoist uuid_is_null() helper from libnvdimm
Hoist the libnvdimm helper as an inline helper to linux/uuid.h
using an auxiliary const variable uuid_null in lib/uuid.c.

[hch: also add the guid variant.  Both do the same but I'd like
to keep casts to a minimum]

The common helper uses the new abstract type uuid_t * instead of
u8 *.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
[hch: added guid_is_null]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:05 +02:00
Vishal Verma 3ae3d67ba7 libnvdimm: add an atomic vs process context flag to rw_bytes
nsio_rw_bytes can clear media errors, but this cannot be done while we
are in an atomic context due to locking within ACPI. From the BTT,
->rw_bytes may be called either from atomic or process context depending
on whether the calls happen during initialization or during IO.

During init, we want to ensure error clearing happens, and the flag
marking process context allows nsio_rw_bytes to do that. When called
during IO, we're in atomic context, and error clearing can be skipped.

Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-10 21:46:22 -07:00
Dan Williams 452bae0aed libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering
A debug patch to turn the standard device_lock() into something that
lockdep can analyze yielded the following:

 ======================================================
 [ INFO: possible circular locking dependency detected ]
 4.11.0-rc4+ #106 Tainted: G           O
 -------------------------------------------------------
 lt-libndctl/1898 is trying to acquire lock:
  (&dev->nvdimm_mutex/3){+.+.+.}, at: [<ffffffffc023c948>] nd_attach_ndns+0x178/0x1b0 [libnvdimm]

 but task is already holding lock:
  (&nvdimm_bus->reconfig_mutex){+.+.+.}, at: [<ffffffffc022e0b1>] nvdimm_bus_lock+0x21/0x30 [libnvdimm]

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (&nvdimm_bus->reconfig_mutex){+.+.+.}:
        lock_acquire+0xf6/0x1f0
        __mutex_lock+0x88/0x980
        mutex_lock_nested+0x1b/0x20
        nvdimm_bus_lock+0x21/0x30 [libnvdimm]
        nvdimm_namespace_capacity+0x1b/0x40 [libnvdimm]
        nvdimm_namespace_common_probe+0x230/0x510 [libnvdimm]
        nd_pmem_probe+0x14/0x180 [nd_pmem]
        nvdimm_bus_probe+0xa9/0x260 [libnvdimm]

 -> #0 (&dev->nvdimm_mutex/3){+.+.+.}:
        __lock_acquire+0x1107/0x1280
        lock_acquire+0xf6/0x1f0
        __mutex_lock+0x88/0x980
        mutex_lock_nested+0x1b/0x20
        nd_attach_ndns+0x178/0x1b0 [libnvdimm]
        nd_namespace_store+0x308/0x3c0 [libnvdimm]
        namespace_store+0x87/0x220 [libnvdimm]

In this case '&dev->nvdimm_mutex/3' mirrors '&dev->mutex'.

Fix this by replacing the use of device_lock() with nvdimm_bus_lock() to protect
nd_{attach,detach}_ndns() operations.

Cc: <stable@vger.kernel.org>
Fixes: 8c2f7e8658 ("libnvdimm: infrastructure for btt devices")
Reported-by: Yi Zhang <yizhan@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-01 08:29:37 -07:00
Vishal Verma abe8b4e3ce nvdimm, btt: add a size attribute for BTTs
To be consistent with other namespaces, expose a 'size' attribute for
BTT devices also.

Cc: Dan Williams <dan.j.williams@intel.com>
Reported-by: Linda Knippers <linda.knippers@hpe.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-08-08 09:26:14 -07:00
Markus Elfring d4c5725d57 libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register"
The __nd_device_register() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-07-24 08:04:55 -07:00
Dan Williams 200c79da82 libnvdimm, pmem, pfn: make pmem_rw_bytes generic and refactor pfn setup
In preparation for providing an alternative (to block device) access
mechanism to persistent memory, convert pmem_rw_bytes() to
nsio_rw_bytes().  This allows ->rw_bytes() functionality without
requiring a 'struct pmem_device' to be instantiated.

In other words, when ->rw_bytes() is in use i/o is driven through
'struct nd_namespace_io', otherwise it is driven through 'struct
pmem_device' and the block layer.  This consolidates the disjoint calls
to devm_exit_badblocks() and devm_memunmap() into a common
devm_nsio_disable() and cleans up the init path to use a unified
pmem_attach_disk() implementation.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-22 12:26:23 -07:00
Dan Williams e32bc729a3 libnvdimm, btt, convert nd_btt_probe() to devm
Pass the device performing the probe so we can use a devm allocation for
the btt superblock.

Cc: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-22 10:59:54 -07:00
Axel Lin 4be9c1fc3d 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>
2015-09-17 11:37:16 -04:00
Dan Williams e1455744b2 libnvdimm, pfn: 'struct page' provider infrastructure
Implement the base infrastructure for libnvdimm PFN devices. Similar to
BTT devices they take a namespace as a backing device and layer
functionality on top. In this case the functionality is reserving space
for an array of 'struct page' entries to be handed out through
pfn_to_page(). For now this is just the basic libnvdimm-device-model for
configuring the base PFN device.

As the namespace claiming mechanism for PFN devices is mostly identical
to BTT devices drivers/nvdimm/claim.c is created to house the common
bits.

Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-28 23:39:36 -04:00
Vishal Verma 6ec689542b libnvdimm, btt: write and validate parent_uuid
When a BTT is instantiated on a namespace it must validate the namespace
uuid matches the 'parent_uuid' stored in the btt superblock. This
property enforces that changing the namespace UUID invalidates all
former BTT instances on that storage. For "IO namespaces" that don't
have a label or UUID, the parent_uuid is set to zero, and this
validation is skipped. For such cases, old BTTs have to be invalidated
by forcing the namespace to raw mode, and overwriting the BTT info
blocks.

Based on a patch by Dan Williams <dan.j.williams@intel.com>

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-14 13:43:04 -04:00
Vishal Verma ab45e76327 libnvdimm, btt: consolidate arena validation
Use arena_is_valid as a common routine for checking the validity of an
info block from both discover_arenas, and nd_btt_probe.

As a result, don't check for validity of the BTT's UUID, and lbasize.
The checksum in the BTT info block guarantees self-consistency, and when
we're called from nd_btt_probe, we don't have a valid uuid or lbasize
available to check against.

Also cleanup to return a bool instead of an int.

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-14 13:43:04 -04:00
Toshi Kani 74ae66c3b1 libnvdimm: Add sysfs numa_node to NVDIMM devices
Add support of sysfs 'numa_node' to I/O-related NVDIMM devices
under /sys/bus/nd/devices, regionN, namespaceN.0, and bttN.x.

An example of numa_node values on a 2-socket system with a single
NVDIMM range on each socket is shown below.
  /sys/bus/nd/devices
  |-- btt0.0/numa_node:0
  |-- btt1.0/numa_node:1
  |-- btt1.1/numa_node:1
  |-- namespace0.0/numa_node:0
  |-- namespace1.0/numa_node:1
  |-- region0/numa_node:0
  |-- region1/numa_node:1

These numa_node files are then linked under the block class of
their device names.
  /sys/class/block/pmem0/device/numa_node:0
  /sys/class/block/pmem1s/device/numa_node:1

This enables numactl(8) to accept 'block:' and 'file:' paths of
pmem and btt devices as shown in the examples below.
  numactl --preferred block:pmem0 --show
  numactl --preferred file:/dev/pmem1s --show

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26 11:23:38 -04:00
Vishal Verma 41cd8b70c3 libnvdimm, btt: add support for blk integrity
Support multiple block sizes (sector + metadata) using the blk integrity
framework. This registers a new integrity template that defines the
protection information tuple size based on the configured metadata size,
and simply acts as a passthrough for protection information generated by
another layer. The metadata is written to the storage as-is, and read back
with each sector.

Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26 11:23:38 -04:00
Vishal Verma 5212e11fde nd_btt: atomic sector updates
BTT stands for Block Translation Table, and is a way to provide power
fail sector atomicity semantics for block devices that have the ability
to perform byte granularity IO. It relies on the capability of libnvdimm
namespace devices to do byte aligned IO.

The BTT works as a stacked blocked device, and reserves a chunk of space
from the backing device for its accounting metadata. It is a bio-based
driver because all IO is done synchronously, and there is no queuing or
asynchronous completions at either the device or the driver level.

The BTT uses 'lanes' to index into various 'on-disk' data structures,
and lanes also act as a synchronization mechanism in case there are more
CPUs than available lanes. We did a comparison between two lane lock
strategies - first where we kept an atomic counter around that tracked
which was the last lane that was used, and 'our' lane was determined by
atomically incrementing that. That way, for the nr_cpus > nr_lanes case,
theoretically, no CPU would be blocked waiting for a lane. The other
strategy was to use the cpu number we're scheduled on to and hash it to
a lane number. Theoretically, this could block an IO that could've
otherwise run using a different, free lane. But some fio workloads
showed that the direct cpu -> lane hash performed faster than tracking
'last lane' - my reasoning is the cache thrash caused by moving the
atomic variable made that approach slower than simply waiting out the
in-progress IO. This supports the conclusion that the driver can be a
very simple bio-based one that does synchronous IOs instead of queuing.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
[jmoyer: fix nmi watchdog timeout in btt_map_init]
[jmoyer: move btt initialization to module load path]
[jmoyer: fix memory leak in the btt initialization path]
[jmoyer: Don't overwrite corrupted arenas]
Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26 11:23:38 -04:00
Dan Williams 8c2f7e8658 libnvdimm: infrastructure for btt devices
NVDIMM namespaces, in addition to accepting "struct bio" based requests,
also have the capability to perform byte-aligned accesses.  By default
only the bio/block interface is used.  However, if another driver can
make effective use of the byte-aligned capability it can claim namespace
interface and use the byte-aligned ->rw_bytes() interface.

The BTT driver is the initial first consumer of this mechanism to allow
adding atomic sector update semantics to a pmem or blk namespace.  This
patch is the sysfs infrastructure to allow configuring a BTT instance
for a namespace.  Enabling that BTT and performing i/o is in a
subsequent patch.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-25 04:20:04 -04:00