This new interface is similar to how struct device (and many others)
work. The caller initializes a 'struct dev_pagemap' as required
and calls 'devm_memremap_pages'. This allows the pagemap structure to
be embedded in another structure and thus container_of can be used. In
this way application specific members can be stored in a containing
struct.
This will be used by the P2P infrastructure and HMM could probably
be cleaned up to use it as well (instead of having it's own, similar
'hmm_devmem_pages_create' function).
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
nfit_test needs to use the poison list manipulation code as well. Make
it more generic and in the process rename poison to badrange, and move
all the related helpers to a new file.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
[vishal: Add badrange.o to nfit_test's Kbuild]
[vishal: add a missed include in bus.c for the new badrange functions]
[vishal: rename all instances of 'be' to 'bre']
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
If we successfully enable a DIMM then it must not be locked and we can
clear the label-read failure condition. Otherwise, we need to reload the
entire bus provider driver to achieve the same effect, and that can
disrupt unrelated DIMMs and namespaces.
Fixes: 9d62ed9651 ("libnvdimm: handle locked label storage areas")
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* Media error handling support in the Block Translation Table (BTT)
driver is reworked to address sleeping-while-atomic locking and
memory-allocation-context conflicts.
* The dax_device lookup overhead for xfs and ext4 is moved out of the
iomap hot-path to a mount-time lookup.
* A new 'ecc_unit_size' sysfs attribute is added to advertise the
read-modify-write boundary property of a persistent memory range.
* Preparatory fix-ups for arm and powerpc pmem support are included
along with other miscellaneous fixes.
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Merge tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm from Dan Williams:
"A rework of media error handling in the BTT driver and other updates.
It has appeared in a few -next releases and collected some late-
breaking build-error and warning fixups as a result.
Summary:
- Media error handling support in the Block Translation Table (BTT)
driver is reworked to address sleeping-while-atomic locking and
memory-allocation-context conflicts.
- The dax_device lookup overhead for xfs and ext4 is moved out of the
iomap hot-path to a mount-time lookup.
- A new 'ecc_unit_size' sysfs attribute is added to advertise the
read-modify-write boundary property of a persistent memory range.
- Preparatory fix-ups for arm and powerpc pmem support are included
along with other miscellaneous fixes"
* tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (26 commits)
libnvdimm, btt: fix format string warnings
libnvdimm, btt: clean up warning and error messages
ext4: fix null pointer dereference on sbi
libnvdimm, nfit: move the check on nd_reserved2 to the endpoint
dax: fix FS_DAX=n BLOCK=y compilation
libnvdimm: fix integer overflow static analysis warning
libnvdimm, nd_blk: remove mmio_flush_range()
libnvdimm, btt: rework error clearing
libnvdimm: fix potential deadlock while clearing errors
libnvdimm, btt: cache sector_size in arena_info
libnvdimm, btt: ensure that flags were also unchanged during a map_read
libnvdimm, btt: refactor map entry operations with macros
libnvdimm, btt: fix a missed NVDIMM_IO_ATOMIC case in the write path
libnvdimm, nfit: export an 'ecc_unit_size' sysfs attribute
ext4: perform dax_device lookup at mount
ext2: perform dax_device lookup at mount
xfs: perform dax_device lookup at mount
dax: introduce a fs_dax_get_by_bdev() helper
libnvdimm, btt: check memory allocation failure
libnvdimm, label: fix index block size calculation
...
The old calculation assumed that the label space was 128k and the label
size is 128. With v1.2 labels where the label size is 256 this
calculation will return zero. We are saved by the fact that the
nsindex_size is always pre-initialized from a previous 128 byte
assumption and we are lucky that the index sizes turn out the same.
Fix this going forward in case we start encountering different
geometries of label areas besides 128k.
Since the label size can change from one call to the next, drop the
caching of nsindex_size.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This way we don't need a block_device structure to submit I/O. The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open. Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).
For the actual I/O path all that we need is the gendisk, which exists
once per block device. But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.
Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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>
No functional change in this patch, just in preparation for
basing the inflight mechanism on the queue in question.
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It is useful to be able to know the position of a DIMM in an
interleave-set. Consider the case where the order of the DIMMs changes
causing a namespace to be invalidated because the interleave-set cookie no
longer matches. If the before and after state of each DIMM position is
known this state debugged by the system owner.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Currently libnvdimm uses HPAGE_SIZE as the default alignment for DAX and
PFN devices. HPAGE_SIZE is the default hugetlbfs page size and when
hugetlbfs is disabled it defaults to PAGE_SIZE. Given DAX has more
in common with THP than hugetlbfs we should proably be using
HPAGE_PMD_SIZE, but this is undefined when THP is disabled so lets just
give it a new name.
The other usage of HPAGE_SIZE in libnvdimm is when determining how large
the altmap should be. For the reasons mentioned above it doesn't really
make sense to use HPAGE_SIZE here either. PMD_SIZE seems to be safe to
use in generic code and it happens to match the vmemmap allocation block
on x86 and Power. It's still a hack, but it's a slightly nicer hack.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
Sysfs "badblocks" information may be updated during run-time that:
- MCE, SCI, and sysfs "scrub" may add new bad blocks
- Writes and ioctl() may clear bad blocks
Add support to send sysfs notifications to sysfs "badblocks" file
under region and pmem directories when their badblocks information
is re-evaluated (but is not necessarily changed) during run-time.
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Linda Knippers <linda.knippers@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
Previously we only honored the lba size for blk-aperture mode
namespaces. For pmem namespaces the lba size was just assumed to be 512.
With the new v1.2 label definition and compatibility with other
operating environments, the ->lbasize property is now respected for pmem
namespaces.
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The interleave-set-cookie algorithm is extended to incorporate all the
same components that are used to generate an nvdimm unique-id. For
backwards compatibility we still maintain the old v1.1 definition.
Reported-by: Nicholas Moulin <nicholas.w.moulin@intel.com>
Reported-by: Kaushik Kanetkar <kaushik.a.kanetkar@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In support of improved interoperability between operating systems and pre-boot
environments the Intel proposed NVDIMM Namespace Specification [1], has been
adopted and modified to the the UEFI 2.7 NVDIMM Label Protocol [2].
Update the definitions of the namespace label data structures so that the new
format can be supported alongside the existing label format.
The new specification changes the default label size to 256 bytes, so
everywhere that relied on sizeof(struct nd_namespace_label) must now use the
sizeof_namespace_label() helper.
There should be no functional differences from these changes as the
default is still the v1.1 128-byte format. Future patches will move the
default to the v1.2 definition.
[1]: http://pmem.io/documents/NVDIMM_Namespace_Spec.pdf
[2]: http://www.uefi.org/sites/default/files/resources/UEFI_Spec_2_7.pdf
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
This is a preparation patch for handling locked nvdimm label regions, a
new concept as introduced by the latest DSM document on pmem.io [1]. A
future patch will leverage nvdimm_set_locked() at DIMM probe time to
flag regions that can not be enabled. There should be no functional
difference resulting from this change.
[1]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example-V1.3.pdf
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
badblocks sysfs file will be export at region level. When nvdimm event
notifier happens for NVDIMM_REVALIATE_POISON, the badblocks in the
region will be updated.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The interleave-set cookie is a sum that sanity checks the composition of
an interleave set has not changed from when the namespace was initially
created. The checksum is calculated by sorting the DIMMs by their
location in the interleave-set. The comparison for the sort must be
64-bit wide, not byte-by-byte as performed by memcmp() in the broken
case.
Fix the implementation to accept correct cookie values in addition to
the Linux "memcmp" order cookies, but only allow correct cookies to be
generated going forward. It does mean that namespaces created by
third-party-tooling, or created by newer kernels with this fix, will not
validate on older kernels. However, there are a couple mitigating
conditions:
1/ platforms with namespace-label capable NVDIMMs are not widely
available.
2/ interleave-sets with a single-dimm are by definition not affected
(nothing to sort). This covers the QEMU-KVM NVDIMM emulation case.
The cookie stored in the namespace label will be fixed by any write the
namespace label, the most straightforward way to achieve this is to
write to the "alt_name" attribute of a namespace in sysfs.
Cc: <stable@vger.kernel.org>
Fixes: eaf961536e ("libnvdimm, nfit: add interleave-set state-tracking infrastructure")
Reported-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com>
Tested-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Platforms like QEMU-KVM implement an NFIT table and label DSMs.
However, since that environment does not define an aliased
configuration, the labels are currently ignored and the kernel registers
a single full-sized pmem-namespace per region. Now that the kernel
supports sub-divisions of pmem regions the labels have a purpose.
Arrange for the labels to be honored when we find an existing / valid
namespace index block.
Cc: <qemu-devel@nongnu.org>
Cc: Haozhong Zhang <haozhong.zhang@intel.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
nd_iostat_start() and nd_iostat_end() implement the same functionality
that generic_start_io_acct() and generic_end_io_acct() already provide.
Change nd_iostat_start() and nd_iostat_end() to call the generic iostat
interfaces. There is no change in the nd interfaces.
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for enabling multiple namespaces per pmem region, convert
the label tracking to use a linked list. In particular this will allow
select_pmem_id() to move labels from the unvalidated state to the
validated state. Currently we only track one validated set per-region.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Before we add more libnvdimm-private fields to nd_mapping make it clear
which parameters are input vs libnvdimm internals. Use struct
nd_mapping_desc instead of struct nd_mapping in nd_region_desc and make
struct nd_mapping private to libnvdimm.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The definition of the flush hint table as:
void __iomem *flush_wpq[0][0];
...passed the unit test, but is broken as flush_wpq[0][1] and
flush_wpq[1][0] refer to the same entry. Fix this to use a helper that
calculates a slot in the table based on the geometry of flush hints in
the region. This is important to get right since virtualization
solutions use this mechanism to trigger hypervisor flushes to platform
persistence.
Reported-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
'ndctl list --buses --dimms' does not list any NVDIMM-Ns since
they are considered as idle. ndctl checks if any driver is
attached to nmem device. nvdimm_probe() always fails in
nvdimm_init_nsarea() since NVDIMM-Ns do not implement optinal
ND_CMD_GET_CONFIG_DATA command.
Change nvdimm_probe() to accept the case that the CONFIG_DATA
command is not implemented for NVDIMM-Ns. The driver attaches
without ndd, which keeps it no-op to the device.
Reported-by: Brian Boylston <brian.boylston@hpe.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
When the NFIT provides multiple flush hint addresses per-dimm it is
expressing that the platform is capable of processing multiple flush
requests in parallel. There is some fixed cost per flush request, let
the cost be shared in parallel on multiple cpus.
Since there may not be enough flush hint addresses for each cpu to have
one, keep a per-cpu index of the last used hint, hash it with current
pid, and assume that access pattern and scheduler randomness will keep
the flush-hint usage somewhat staggered across cpus.
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for triggering flushes of a DIMM's writes-posted-queue
(WPQ) via the pmem driver move mapping of flush hint addresses to the
region driver. Since this uses devm_nvdimm_memremap() the flush
addresses will remain mapped while any region to which the dimm belongs
is active.
We need to communicate more information to the nvdimm core to facilitate
this mapping, namely each dimm object now carries an array of flush hint
address resources.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that all shared mappings are handled by devm_nvdimm_memremap() we no
longer need nfit_spa_map() nor do we need to trigger a callback to the
bus provider at region disable time.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
For autodetecting a previously established dax configuration we need the
info block to indicate block-device vs device-dax mode, and we need to
have the default namespace probe hand-off the configuration to the
dax_pmem driver.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Device DAX is the device-centric analogue of Filesystem DAX
(CONFIG_FS_DAX). It allows persistent memory ranges to be allocated and
mapped without need of an intervening file system. This initial
infrastructure arranges for a libnvdimm pfn-device to be represented as
a different device-type so that it can be attached to a driver other
than the pmem driver.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that pmem internals have been disentangled from pfn setup, that code
can move to the core. This is in preparation for adding another user of
the pfn-device capabilities.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
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>
Pass the device performing the probe so we can use a devm allocation for
the pfn superblock.
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
We can derive the common namespace from other information. We also do
not need to cache it because all the usages are in slow paths.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
When section alignment padding is in effect we need to shift / truncate
the range that is queried for poison by the 'start_pad' or 'end_trunc'
reservations.
It's easiest if we just pass in an adjusted resource range rather than
deriving it from the passed in namespace. With the resource range
resolution pushed out to the caller we can also push the
namespace-to-region lookup to the caller and drop the implicit pmem-type
assumption about the passed in namespace object.
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
If a write is directed at a known bad block perform the following:
1/ write the data
2/ send a clear poison command
3/ invalidate the poison out of the cache hierarchy
Cc: <x86@kernel.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for asynchronous address range scrub support add an
ability for the pmem driver to dynamically consume address range scrub
results.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
If a device will ever have badblocks it should always have a badblocks
instance available. So, similar to md, embed a badblocks instance in
pmem_device. This reduces pointer chasing in the i/o fast path, and
simplifies the init path.
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
During region creation, perform Address Range Scrubs (ARS) for the SPA
(System Physical Address) ranges to retrieve known poison locations from
firmware. Add a new data structure 'nd_poison' which is used as a list
in nvdimm_bus to store these poison locations.
When creating a pmem namespace, if there is any known poison associated
with its physical address space, convert the poison ranges to bad sectors
that are exposed using the badblocks interface.
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
When setting aside capacity for struct page it must be aligned to the
largest mapping size that is to be made available via DAX. Make the
alignment configurable to enable support for 1GiB page-size mappings.
The offset for PFN_MODE_RAM may now be larger than SZ_8K, so fixup the
offset check in nvdimm_namespace_attach_pfn().
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The alignment constraint isn't necessary now that devm_memremap_pages()
allows for unaligned mappings.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The expectation is that the legacy / non-standard pmem discovery method
(e820 type-12) will only ever be used to describe small quantities of
persistent memory. Larger capacities will be described via the ACPI
NFIT. When "allocate struct page from pmem" support is added this default
policy can be overridden by assigning a legacy pmem namespace to a pfn
device, however this would be only be necessary if a platform used the
legacy mechanism to define a very large range.
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Enable the pmem driver to handle PFN device instances. Attaching a pmem
namespace to a pfn device triggers the driver to allocate and initialize
struct page entries for pmem. Memory capacity for this allocation comes
exclusively from RAM for now which is suitable for low PMEM to RAM
ratios. This mechanism will be expanded later for setting an "allocate
from PMEM" policy.
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
Christoph Hellwig