Commit Graph

20 Commits

Author SHA1 Message Date
Dan Williams
b18d4b8a25 libnvdimm, namespace: fix label initialization to use valid seq numbers
The set of valid sequence numbers is {1,2,3}. The specification
indicates that an implementation should consider 0 a sign of a critical
error:

    UEFI 2.7: 13.19 NVDIMM Label Protocol

    Software never writes the sequence number 00, so a correctly
    check-summed Index Block with this sequence number probably indicates a
    critical error. When software discovers this case it treats it as an
    invalid Index Block indication.

While the expectation is that the invalid block is just thrown away, the
Robustness Principle says we should fix this to make both sequence
numbers valid.

Fixes: f524bf271a ("libnvdimm: write pmem label set")
Cc: <stable@vger.kernel.org>
Reported-by: Juston Li <juston.li@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-28 09:13:06 -07:00
Dan Williams
0288176869 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>
2017-08-29 18:28:18 -07:00
Dan Williams
2de5148ffb libnvdimm, namespace: record 'lbasize' for pmem namespaces
Commit f979b13c3c "libnvdimm, label: honor the lba size specified in
v1.2 labels") neglected to update the 'lbasize' in the label when the
namespace sector_size attribute was written. We need this value in the
label for inter-OS / pre-OS compatibility.

Fixes: f979b13c3c ("libnvdimm, label: honor the lba size specified in v1.2 labels")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-07-03 16:30:44 -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
8990cdf10c libnvdimm, label: switch to using v1.2 labels by default
The rules for which version of the label specification are in effect at
any given point in time are as follows:

1/ If a DIMM has an existing / valid index block then the version
   specified is used regardless if it is a previous version.

2/ By default when the kernel is initializing new index blocks the
   latest specification version (v1.2 at time of writing) is used.

3/ An environment that wants to force create v1.1 label-sets must
   arrange for userspace to disable all active regions / namespaces /
   dimms and write a valid set of v1.1 index blocks to the dimms.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15 14:31:41 -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
Dan Williams
355d838878 libnvdimm, label: add v1.2 label checksum support
The v1.2 namespace label specification adds a fletcher checksum to each
label instance. Add generation and validation support for the new field.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15 14:31:40 -07:00
Dan Williams
3934d8410c libnvdimm, label: update 'nlabel' and 'position' handling for local namespaces
The v1.2 namespace label specification requires 'nlabel' and 'position'
to be valid for the first ("lowest dpa") label in the set. It also
requires all non-first labels to set those fields to 0xff.

Linux does not much care if these values are correct, because we can
just trust the count of labels with the matching uuid like the v1.1
case. However, we set them correctly in case other environments care.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15 14:31:40 -07:00
Dan Williams
8f2bc2430e libnvdimm, label: populate 'isetcookie' for blk-aperture namespaces
Starting with the v1.2 definition of namespace labels, the isetcookie
field is populated and validated for blk-aperture namespaces. This adds
some safety against inadvertent copying of namespace labels from one
DIMM-device to another.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15 14:31:40 -07:00
Dan Williams
faec6f8a1c libnvdimm, label: populate the type_guid property for v1.2 namespaces
The type_guid refers to the "Address Range Type GUID" for the region
backing a namespace as defined the ACPI NFIT (NVDIMM Firmware Interface
Table). This 'type' identifier specifies an access mechanism for the
given namespace. This capability replaces the confusing usage of the
'NSLABEL_FLAG_LOCAL' flag to indicate a block-aperture-mode namespace.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15 14:31:40 -07:00
Dan Williams
c12c48ce86 libnvdimm, label: add v1.2 interleave-set-cookie algorithm
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>
2017-06-15 14:31:39 -07:00
Dan Williams
564e871aa6 libnvdimm, label: add v1.2 nvdimm label definitions
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>
2017-06-15 14:31:39 -07:00
Nicolas Iooss
2d9a02744f nvdimm: use the right length of "pmem"
In order to test that the name of a resource begins with "pmem", call
strncmp() with 4 as length instead of 3 to match the whole prefix.

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-11-11 20:37:42 -08:00
Dan Williams
16660eaea0 libnvdimm, namespace: update label implementation for multi-pmem
Instead of assuming that there will only ever be one allocated range at
the start of the region, account for additional namespaces that might
start at an offset from the region base.

After this change pmem namespaces now have a reason to carry an array of
resources similar to blk.  Unifying the resource tracking infrastructure
in nd_namespace_common is a future cleanup candidate.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-10-07 09:22:53 -07:00
Dan Williams
ae8219f186 libnvdimm, label: convert label tracking to a linked list
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>
2016-09-30 19:13:42 -07:00
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
Dan Williams
0ba1c63489 libnvdimm: write blk label set
After 'uuid', 'size', 'sector_size', and optionally 'alt_name' have been
set to valid values the labels on the dimm can be updated.  The
difference with the pmem case is that blk namespaces are limited to one
dimm and can cover discontiguous ranges in dpa space.

Also, after allocating label slots, it is useful for userspace to know
how many slots are left.  Export this information in sysfs.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams
f524bf271a libnvdimm: write pmem label set
After 'uuid', 'size', and optionally 'alt_name' have been set to valid
values the labels on the dimms can be updated.

Write procedure is:
1/ Allocate and write new labels in the "next" index
2/ Free the old labels in the working copy
3/ Write the bitmap and the label space on the dimm
4/ Write the index to make the update valid

Label ranges directly mirror the dpa resource values for the given
label_id of the namespace.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams
bf9bccc14c libnvdimm: pmem label sets and namespace instantiation.
A complete label set is a PMEM-label per-dimm per-interleave-set where
all the UUIDs match and the interleave set cookie matches the hosting
interleave set.

Present sysfs attributes for manipulation of a PMEM-namespace's
'alt_name', 'uuid', and 'size' attributes.  A later patch will make
these settings persistent by writing back the label.

Note that PMEM allocations grow forwards from the start of an interleave
set (lowest dimm-physical-address (DPA)).  BLK-namespaces that alias
with a PMEM interleave set will grow allocations backward from the
highest DPA.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams
4a826c83db libnvdimm: namespace indices: read and validate
This on media label format [1] consists of two index blocks followed by
an array of labels.  None of these structures are ever updated in place.
A sequence number tracks the current active index and the next one to
write, while labels are written to free slots.

    +------------+
    |            |
    |  nsindex0  |
    |            |
    +------------+
    |            |
    |  nsindex1  |
    |            |
    +------------+
    |   label0   |
    +------------+
    |   label1   |
    +------------+
    |            |
     ....nslot...
    |            |
    +------------+
    |   labelN   |
    +------------+

After reading valid labels, store the dpa ranges they claim into
per-dimm resource trees.

[1]: http://pmem.io/documents/NVDIMM_Namespace_Spec.pdf

Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00