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2015-09-08Merge tag 'libnvdimm-for-4.3' of ↵Linus Torvalds1-43/+36
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: "This update has successfully completed a 0day-kbuild run and has appeared in a linux-next release. The changes outside of the typical drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and the introduction of ZONE_DEVICE + devm_memremap_pages(). Summary: - Introduce ZONE_DEVICE and devm_memremap_pages() as a generic mechanism for adding device-driver-discovered memory regions to the kernel's direct map. This facility is used by the pmem driver to enable pfn_to_page() operations on the page frames returned by DAX ('direct_access' in 'struct block_device_operations'). For now, the 'memmap' allocation for these "device" pages comes from "System RAM". Support for allocating the memmap from device memory will arrive in a later kernel. - Introduce memremap() to replace usages of ioremap_cache() and ioremap_wt(). memremap() drops the __iomem annotation for these mappings to memory that do not have i/o side effects. The replacement of ioremap_cache() with memremap() is limited to the pmem driver to ease merging the api change in v4.3. Completion of the conversion is targeted for v4.4. - Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem driver, update the VFS DAX implementation and PMEM api to provide persistence guarantees for kernel operations on a DAX mapping. - Convert the ACPI NFIT 'BLK' driver to map the block apertures as cacheable to improve performance. - Miscellaneous updates and fixes to libnvdimm including support for issuing "address range scrub" commands, clarifying the optimal 'sector size' of pmem devices, a clarification of the usage of the ACPI '_STA' (status) property for DIMM devices, and other minor fixes" * tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits) libnvdimm, pmem: direct map legacy pmem by default libnvdimm, pmem: 'struct page' for pmem libnvdimm, pfn: 'struct page' provider infrastructure x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB add devm_memremap_pages mm: ZONE_DEVICE for "device memory" mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h dax: drop size parameter to ->direct_access() nd_blk: change aperture mapping from WC to WB nvdimm: change to use generic kvfree() pmem, dax: have direct_access use __pmem annotation dax: update I/O path to do proper PMEM flushing pmem: add copy_from_iter_pmem() and clear_pmem() pmem, x86: clean up conditional pmem includes pmem: remove layer when calling arch_has_wmb_pmem() pmem, x86: move x86 PMEM API to new pmem.h header libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option pmem: switch to devm_ allocations devres: add devm_memremap libnvdimm, btt: write and validate parent_uuid ...
2015-08-27x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WBDan Williams1-1/+2
Given that a write-back (WB) mapping plus non-temporal stores is expected to be the most efficient way to access PMEM, update the definition of ARCH_HAS_PMEM_API to imply arch support for WB-mapped-PMEM. This is needed as a pre-requisite for adding PMEM to the direct map and mapping it with struct page. The above clarification for X86_64 means that memcpy_to_pmem() is permitted to use the non-temporal arch_memcpy_to_pmem() rather than needlessly fall back to default_memcpy_to_pmem() when the pcommit instruction is not available. When arch_memcpy_to_pmem() is not guaranteed to flush writes out of cache, i.e. on older X86_32 implementations where non-temporal stores may just dirty cache, ARCH_HAS_PMEM_API is simply disabled. The default fall back for persistent memory handling remains. Namely, map it with the WT (write-through) cache-type and hope for the best. arch_has_pmem_api() is updated to only indicate whether the arch provides the proper helpers to meet the minimum "writes are visible outside the cache hierarchy after memcpy_to_pmem() + wmb_pmem()". Code that cares whether wmb_pmem() actually flushes writes to pmem must now call arch_has_wmb_pmem() directly. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> [hch: set ARCH_HAS_PMEM_API=n on x86_32] Reviewed-by: Christoph Hellwig <hch@lst.de> [toshi: x86_32 compile fixes] Signed-off-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-27nd_blk: change aperture mapping from WC to WBRoss Zwisler1-24/+31
This should result in a pretty sizeable performance gain for reads. For rough comparison I did some simple read testing using PMEM to compare reads of write combining (WC) mappings vs write-back (WB). This was done on a random lab machine. PMEM reads from a write combining mapping: # dd of=/dev/null if=/dev/pmem0 bs=4096 count=100000 100000+0 records in 100000+0 records out 409600000 bytes (410 MB) copied, 9.2855 s, 44.1 MB/s PMEM reads from a write-back mapping: # dd of=/dev/null if=/dev/pmem0 bs=4096 count=1000000 1000000+0 records in 1000000+0 records out 4096000000 bytes (4.1 GB) copied, 3.44034 s, 1.2 GB/s To be able to safely support a write-back aperture I needed to add support for the "read flush" _DSM flag, as outlined in the DSM spec: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf This flag tells the ND BLK driver that it needs to flush the cache lines associated with the aperture after the aperture is moved but before any new data is read. This ensures that any stale cache lines from the previous contents of the aperture will be discarded from the processor cache, and the new data will be read properly from the DIMM. We know that the cache lines are clean and will be discarded without any writeback because either a) the previous aperture operation was a read, and we never modified the contents of the aperture, or b) the previous aperture operation was a write and we must have written back the dirtied contents of the aperture to the DIMM before the I/O was completed. In order to add support for the "read flush" flag I needed to add a generic routine to invalidate cache lines, mmio_flush_range(). This is protected by the ARCH_HAS_MMIO_FLUSH Kconfig variable, and is currently only supported on x86. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-27nfit: Clarify memory device state flags stringsToshi Kani1-10/+10
ACPI 6.0 NFIT Memory Device State Flags in Table 5-129 defines NVDIMM status as follows. These bits indicate multiple info, such as failures, pending event, and capability. Bit [0] set to 1 to indicate that the previous SAVE to the Memory Device failed. Bit [1] set to 1 to indicate that the last RESTORE from the Memory Device failed. Bit [2] set to 1 to indicate that platform flush of data to Memory Device failed. As a result, the restored data content may be inconsistent even if SAVE and RESTORE do not indicate failure. Bit [3] set to 1 to indicate that the Memory Device is observed to be not armed prior to OSPM hand off. A Memory Device is considered armed if it is able to accept persistent writes. Bit [4] set to 1 to indicate that the Memory Device observed SMART and health events prior to OSPM handoff. /sys/bus/nd/devices/nmemX/nfit/flags shows this flags info. The output strings associated with the bits are "save", "restore", "smart", etc., which can be confusing as they may be interpreted as positive status, i.e. save succeeded. Change also the dev_info() message in acpi_nfit_register_dimms() to be consistent with the sysfs flags strings. Reported-by: Robert Elliott <elliott@hp.com> Signed-off-by: Toshi Kani <toshi.kani@hp.com> [ross: rename 'not_arm' to 'not_armed'] Cc: Ross Zwisler <ross.zwisler@linux.intel.com> [djbw: defer adding bit5, HEALTH_ENABLED, for now] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-25nfit, nd_blk: BLK status register is only 32 bitsRoss Zwisler1-2/+2
Only read 32 bits for the BLK status register in read_blk_stat(). The format and size of this register is defined in the "NVDIMM Driver Writer's guide": http://pmem.io/documents/NVDIMM_Driver_Writers_Guide.pdf Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reported-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com> Tested-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-07-27nfit: Don't check _STA on NVDIMM devicesLinda Knippers1-18/+2
The _STA only applies to the root device, not the individual NVDIMMS, so don't check here. NVDIMM device state flags are checked elsewhere. Signed-off-by: Linda Knippers <linda.knippers@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-07-27libnvdimm: Add DSM support for Address Range Scrub commandsVishal Verma1-0/+1
Add support for the three ARS DSM commands: - Query ARS Capabilities - Queries the firmware to check if a given range supports scrub, and if so, which type (persistent vs. volatile) - Start ARS - Starts a scrub for a given range/type - Query ARS Status - Checks status of a previously started scrub, and provides the error logs if any. The commands are described by the example DSM spec at: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf Also add these commands to the nfit_test test framework, and return canned data. Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-07-10nfit: add support for NVDIMM "latch" flagRoss Zwisler1-1/+32
Add support in the NFIT BLK I/O path for the "latch" flag defined in the "Get Block NVDIMM Flags" _DSM function: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf This flag requires the driver to read back the command register after it is written in the block I/O path. This ensures that the hardware has fully processed the new command and moved the aperture appropriately. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-07-10nfit: update block I/O path to use PMEM APIRoss Zwisler1-11/+86
Update the nfit block I/O path to use the new PMEM API and to adhere to the read/write flows outlined in the "NVDIMM Block Window Driver Writer's Guide": http://pmem.io/documents/NVDIMM_Driver_Writers_Guide.pdf This includes adding support for targeted NVDIMM flushes called "flush hints" in the ACPI 6.0 specification: http://www.uefi.org/sites/default/files/resources/ACPI_6.0.pdf For performance and media durability the mapping for a BLK aperture is moved to a write-combining mapping which is consistent with memcpy_to_pmem() and wmb_blk(). Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-30nfit: fix smatch "use after null check" reportDan Williams1-2/+2
drivers/acpi/nfit.c:1224 acpi_nfit_blk_region_enable() error: we previously assumed 'nfit_mem' could be null (see line 1223) drivers/acpi/nfit.c 1222 nfit_mem = nvdimm_provider_data(nvdimm); 1223 if (!nfit_mem || !nfit_mem->dcr || !nfit_mem->bdw) { ^^^^^^^^ Check. 1224 dev_dbg(dev, "%s: missing%s%s%s\n", __func__, 1225 nfit_mem ? "" : " nfit_mem", 1226 nfit_mem->dcr ? "" : " dcr", ^^^^^^^^^^^^^ Unchecked dereference. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26libnvdimm: Add sysfs numa_node to NVDIMM devicesToshi Kani1-0/+1
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>
2015-06-26libnvdimm: Set numa_node to NVDIMM devicesToshi Kani1-0/+6
ACPI NFIT table has System Physical Address Range Structure entries that describe a proximity ID of each range when ACPI_NFIT_PROXIMITY_VALID is set in the flags. Change acpi_nfit_register_region() to map a proximity ID to its node ID, and set it to a new numa_node field of nd_region_desc, which is then conveyed to the nd_region device. The device core arranges for btt and namespace devices to inherit their node from their parent region. Signed-off-by: Toshi Kani <toshi.kani@hp.com> [djbw: move set_dev_node() from region.c to bus.c] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26libnvdimm, nfit: handle unarmed dimms, mark namespaces read-onlyDan Williams1-0/+31
Upon detection of an unarmed dimm in a region, arrange for descendant BTT, PMEM, or BLK instances to be read-only. A dimm is primarily marked "unarmed" via flags passed by platform firmware (NFIT). The flags in the NFIT memory device sub-structure indicate the state of the data on the nvdimm relative to its energy source or last "flush to persistence". For the most part there is nothing the driver can do but advertise the state of these flags in sysfs and emit a message if firmware indicates that the contents of the device may be corrupted. However, for the case of ACPI_NFIT_MEM_ARMED, the driver can arrange for the block devices incorporating that nvdimm to be marked read-only. This is a safe default as the data is still available and new writes are held off until the administrator either forces read-write mode, or the energy source becomes armed. A 'read_only' attribute is added to REGION devices to allow for overriding the default read-only policy of all descendant block devices. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26tools/testing/nvdimm: libnvdimm unit test infrastructureDan Williams1-4/+8
'libnvdimm' is the first driver sub-system in the kernel to implement mocking for unit test coverage. The nfit_test module gets built as an external module and arranges for external module replacements of nfit, libnvdimm, nd_pmem, and nd_blk. These replacements use the linker --wrap option to redirect calls to ioremap() + request_mem_region() to custom defined unit test resources. The end result is a fully functional nvdimm_bus, as far as userspace is concerned, but with the capability to perform otherwise destructive tests on emulated resources. Q: Why not use QEMU for this emulation? QEMU is not suitable for unit testing. QEMU's role is to faithfully emulate the platform. A unit test's role is to unfaithfully implement the platform with the goal of triggering bugs in the corners of the sub-system implementation. As bugs are discovered in platforms, or the sub-system itself, the unit tests are extended to backstop a fix with a reproducer unit test. Another problem with QEMU is that it would require coordination of 3 software projects instead of 2 (kernel + libndctl [1]) to maintain and execute the tests. The chances for bit rot and the difficulty of getting the tests running goes up non-linearly the more components involved. Q: Why submit this to the kernel tree instead of external modules in libndctl? Simple, to alleviate the same risk that out-of-tree external modules face. Updates to drivers/nvdimm/ can be immediately evaluated to see if they have any impact on tools/testing/nvdimm/. Q: What are the negative implications of merging this? It is a unique maintenance burden because the purpose of mocking an interface to enable a unit test is to purposefully short circuit the semantics of a routine to enable testing. For example __wrap_ioremap_cache() fakes the pmem driver into "ioremap()'ing" a test resource buffer allocated by dma_alloc_coherent(). The future maintenance burden hits when someone changes the semantics of ioremap_cache() and wonders what the implications are for the unit test. [1]: https://github.com/pmem/ndctl Cc: <linux-acpi@vger.kernel.org> Cc: Lv Zheng <lv.zheng@intel.com> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memoryRoss Zwisler1-14/+435
The libnvdimm implementation handles allocating dimm address space (DPA) between PMEM and BLK mode interfaces. After DPA has been allocated from a BLK-region to a BLK-namespace the nd_blk driver attaches to handle I/O as a struct bio based block device. Unlike PMEM, BLK is required to handle platform specific details like mmio register formats and memory controller interleave. For this reason the libnvdimm generic nd_blk driver calls back into the bus provider to carry out the I/O. This initial implementation handles the BLK interface defined by the ACPI 6 NFIT [1] and the NVDIMM DSM Interface Example [2] composed from DCR (dimm control region), BDW (block data window), IDT (interleave descriptor) NFIT structures and the hardware register format. [1]: http://www.uefi.org/sites/default/files/resources/ACPI_6.0.pdf [2]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf 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> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26nd_btt: atomic sector updatesVishal Verma1-0/+1
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>
2015-06-24libnvdimm, nfit: add interleave-set state-tracking infrastructureDan Williams1-2/+91
On platforms that have firmware support for reading/writing per-dimm label space, a portion of the dimm may be accessible via an interleave set PMEM mapping in addition to the dimm's BLK (block-data-window aperture(s)) interface. A label, stored in a "configuration data region" on the dimm, disambiguates which dimm addresses are accessed through which exclusive interface. Add infrastructure that allows the kernel to block modifications to a label in the set while any member dimm is active. Note that this is meant only for enforcing "no modifications of active labels" via the coarse ioctl command. Adding/deleting namespaces from an active interleave set is always possible via sysfs. Another aspect of tracking interleave sets is tracking their integrity when DIMMs in a set are physically re-ordered. For this purpose we generate an "interleave-set cookie" that can be recorded in a label and validated against the current configuration. It is the bus provider implementation's responsibility to calculate the interleave set cookie and attach it to a given region. Cc: Neil Brown <neilb@suse.de> Cc: <linux-acpi@vger.kernel.org> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24libnvdimm: support for legacy (non-aliasing) nvdimmsDan Williams1-0/+1
The libnvdimm region driver is an intermediary driver that translates non-volatile "region"s into "namespace" sub-devices that are surfaced by persistent memory block-device drivers (PMEM and BLK). ACPI 6 introduces the concept that a given nvdimm may simultaneously offer multiple access modes to its media through direct PMEM load/store access, or windowed BLK mode. Existing nvdimms mostly implement a PMEM interface, some offer a BLK-like mode, but never both as ACPI 6 defines. If an nvdimm is single interfaced, then there is no need for dimm metadata labels. For these devices we can take the region boundaries directly to create a child namespace device (nd_namespace_io). Acked-by: Christoph Hellwig <hch@lst.de> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24libnvdimm, nfit: regions (block-data-window, persistent memory, volatile memory)Dan Williams1-1/+147
A "region" device represents the maximum capacity of a BLK range (mmio block-data-window(s)), or a PMEM range (DAX-capable persistent memory or volatile memory), without regard for aliasing. Aliasing, in the dimm-local address space (DPA), is resolved by metadata on a dimm to designate which exclusive interface will access the aliased DPA ranges. Support for the per-dimm metadata/label arrvies is in a subsequent patch. The name format of "region" devices is "regionN" where, like dimms, N is a global ida index assigned at discovery time. This id is not reliable across reboots nor in the presence of hotplug. Look to attributes of the region or static id-data of the sub-namespace to generate a persistent name. However, if the platform configuration does not change it is reasonable to expect the same region id to be assigned at the next boot. "region"s have 2 generic attributes "size", and "mapping"s where: - size: the BLK accessible capacity or the span of the system physical address range in the case of PMEM. - mappingN: a tuple describing a dimm's contribution to the region's capacity in the format (<nmemX>,<dpa>,<size>). For a PMEM-region there will be at least one mapping per dimm in the interleave set. For a BLK-region there is only "mapping0" listing the starting DPA of the BLK-region and the available DPA capacity of that space (matches "size" above). The max number of mappings per "region" is hard coded per the constraints of sysfs attribute groups. That said the number of mappings per region should never exceed the maximum number of possible dimms in the system. If the current number turns out to not be enough then the "mappings" attribute clarifies how many there are supposed to be. "32 should be enough for anybody...". Cc: Neil Brown <neilb@suse.de> Cc: <linux-acpi@vger.kernel.org> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24libnvdimm, nvdimm: dimm driver and base libnvdimm device-driver infrastructureDan Williams1-3/+10
* Implement the device-model infrastructure for loading modules and attaching drivers to nvdimm devices. This is a simple association of a nd-device-type number with a driver that has a bitmask of supported device types. To facilitate userspace bind/unbind operations 'modalias' and 'devtype', that also appear in the uevent, are added as generic sysfs attributes for all nvdimm devices. The reason for the device-type number is to support sub-types within a given parent devtype, be it a vendor-specific sub-type or otherwise. * The first consumer of this infrastructure is the driver for dimm devices. It simply uses control messages to retrieve and store the configuration-data image (label set) from each dimm. Note: nd_device_register() arranges for asynchronous registration of nvdimm bus devices by default. Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Neil Brown <neilb@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devicesDan Williams1-2/+214
Most discovery/configuration of the nvdimm-subsystem is done via sysfs attributes. However, some nvdimm_bus instances, particularly the ACPI.NFIT bus, define a small set of messages that can be passed to the platform. For convenience we derive the initial libnvdimm-ioctl command formats directly from the NFIT DSM Interface Example formats. ND_CMD_SMART: media health and diagnostics ND_CMD_GET_CONFIG_SIZE: size of the label space ND_CMD_GET_CONFIG_DATA: read label space ND_CMD_SET_CONFIG_DATA: write label space ND_CMD_VENDOR: vendor-specific command passthrough ND_CMD_ARS_CAP: report address-range-scrubbing capabilities ND_CMD_ARS_START: initiate scrubbing ND_CMD_ARS_STATUS: report on scrubbing state ND_CMD_SMART_THRESHOLD: configure alarm thresholds for smart events If a platform later defines different commands than this set it is straightforward to extend support to those formats. Most of the commands target a specific dimm. However, the address-range-scrubbing commands target the bus. The 'commands' attribute in sysfs of an nvdimm_bus, or nvdimm, enumerate the supported commands for that object. Cc: <linux-acpi@vger.kernel.org> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reported-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24libnvdimm, nfit: dimm/memory-devicesDan Williams1-1/+160
Enable nvdimm devices to be registered on a nvdimm_bus. The kernel assigned device id for nvdimm devicesis dynamic. If userspace needs a more static identifier it should consult a provider-specific attribute. In the case where NFIT is the provider, the 'nmemX/nfit/handle' or 'nmemX/nfit/serial' attributes may be used for this purpose. Cc: Neil Brown <neilb@suse.de> Cc: <linux-acpi@vger.kernel.org> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24libnvdimm: control character device and nvdimm_bus sysfs attributesDan Williams1-0/+28
The control device for a nvdimm_bus is registered as an "nd" class device. The expectation is that there will usually only be one "nd" bus registered under /sys/class/nd. However, we allow for the possibility of multiple buses and they will listed in discovery order as ndctl0...ndctlN. This character device hosts the ioctl for passing control messages. The initial command set has a 1:1 correlation with the commands listed in the by the "NFIT DSM Example" document [1], but this scheme is extensible to future command sets. Note, nd_ioctl() and the backing ->ndctl() implementation are defined in a subsequent patch. This is simply the initial registrations and sysfs attributes. [1]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf Cc: Neil Brown <neilb@suse.de> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: <linux-acpi@vger.kernel.org> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24libnvdimm, nfit: initial libnvdimm infrastructure and NFIT supportDan Williams1-0/+481
A struct nvdimm_bus is the anchor device for registering nvdimm resources and interfaces, for example, a character control device, nvdimm devices, and I/O region devices. The ACPI NFIT (NVDIMM Firmware Interface Table) is one possible platform description for such non-volatile memory resources in a system. The nfit.ko driver attaches to the "ACPI0012" device that indicates the presence of the NFIT and parses the table to register a struct nvdimm_bus instance. Cc: <linux-acpi@vger.kernel.org> Cc: Lv Zheng <lv.zheng@intel.com> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>