kernel/linux.git/drivers/nvdimm, branch linux-4.20.y

mm, devm_memremap_pages: fix shutdown handling

2019-01-13T08:24:03+00:00

commit a95c90f1e2c253b280385ecf3d4ebfe476926b28 upstream. The last step before devm_memremap_pages() returns success is to allocate a release action, devm_memremap_pages_release(), to tear the entire setup down. However, the result from devm_add_action() is not checked. Checking the error from devm_add_action() is not enough. The api currently relies on the fact that the percpu_ref it is using is killed by the time the devm_memremap_pages_release() is run. Rather than continue this awkward situation, offload the responsibility of killing the percpu_ref to devm_memremap_pages_release() directly. This allows devm_memremap_pages() to do the right thing relative to init failures and shutdown. Without this change we could fail to register the teardown of devm_memremap_pages(). The likelihood of hitting this failure is tiny as small memory allocations almost always succeed. However, the impact of the failure is large given any future reconfiguration, or disable/enable, of an nvdimm namespace will fail forever as subsequent calls to devm_memremap_pages() will fail to setup the pgmap_radix since there will be stale entries for the physical address range. An argument could be made to require that the ->kill() operation be set in the @pgmap arg rather than passed in separately. However, it helps code readability, tracking the lifetime of a given instance, to be able to grep the kill routine directly at the devm_memremap_pages() call site. Link: http://lkml.kernel.org/r/154275558526.76910.7535251937849268605.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Fixes: e8d513483300 ("memremap: change devm_memremap_pages interface...") Reviewed-by: "Jérôme Glisse" Reported-by: Logan Gunthorpe Reviewed-by: Logan Gunthorpe Reviewed-by: Christoph Hellwig Cc: Balbir Singh Cc: Michal Hocko Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

libnvdimm, pfn: Pad pfn namespaces relative to other regions

2018-12-05T22:16:12+00:00

Commit cfe30b872058 "libnvdimm, pmem: adjust for section collisions with 'System RAM'" enabled Linux to workaround occasions where platform firmware arranges for "System RAM" and "Persistent Memory" to collide within a single section boundary. Unfortunately, as reported in this issue [1], platform firmware can inflict the same collision between persistent memory regions. The approach of interrogating iomem_resource does not work in this case because platform firmware may merge multiple regions into a single iomem_resource range. Instead provide a method to interrogate regions that share the same parent bus. This is a stop-gap until the core-MM can grow support for hotplug on sub-section boundaries. [1]: https://github.com/pmem/ndctl/issues/76 Fixes: cfe30b872058 ("libnvdimm, pmem: adjust for section collisions with...") Cc: Reported-by: Patrick Geary Tested-by: Patrick Geary Reviewed-by: Vishal Verma Signed-off-by: Dan Williams

Merge tag 'libnvdimm-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2018-10-25T13:31:56+00:00

Pull libnvdimm updates from Dan Williams: - Improve the efficiency and performance of reading nvdimm-namespace labels. Reduce the amount of label data read at driver load time by a few orders of magnitude. Reduce heavyweight call-outs to platform-firmware routines. - Handle media errors located in the 'struct page' array stored on a persistent memory namespace. Let the kernel clear these errors rather than an awkward userspace workaround. - Fix Address Range Scrub (ARS) completion tracking. Correct occasions where the kernel indicates completion of ARS before submission. - Fix asynchronous device registration reference counting. - Add support for reporting an nvdimm dirty-shutdown-count via sysfs. - Fix various small libnvdimm core and uapi issues. * tag 'libnvdimm-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits) acpi, nfit: Further restrict userspace ARS start requests acpi, nfit: Fix Address Range Scrub completion tracking UAPI: ndctl: Remove use of PAGE_SIZE UAPI: ndctl: Fix g++-unsupported initialisation in headers tools/testing/nvdimm: Populate dirty shutdown data acpi, nfit: Collect shutdown status acpi, nfit: Introduce nfit_mem flags libnvdimm, label: Fix sparse warning nvdimm: Use namespace index data to reduce number of label reads needed nvdimm: Split label init out from the logic for getting config data nvdimm: Remove empty if statement nvdimm: Clarify comment in sizeof_namespace_index nvdimm: Sanity check labeloff libnvdimm, dimm: Maximize label transfer size libnvdimm, pmem: Fix badblocks population for 'raw' namespaces libnvdimm, namespace: Drop the repeat assignment for variable dev->parent libnvdimm, region: Fail badblocks listing for inactive regions libnvdimm, pfn: during init, clear errors in the metadata area libnvdimm: Set device node in nd_device_register libnvdimm: Hold reference on parent while scheduling async init ...

libnvdimm, label: Fix sparse warning

2018-10-12T15:39:41+00:00

The kbuild robot reports: drivers/nvdimm/label.c:500:32: warning: restricted __le32 degrades to integer ...read 'nslot' into a local u32. Reported-by: kbuild test robot Acked-by: Alexander Duyck Signed-off-by: Dan Williams

nvdimm: Use namespace index data to reduce number of label reads needed

2018-10-12T15:39:31+00:00

This patch adds logic that is meant to make use of the namespace index data to reduce the number of reads that are needed to initialize a given namespace. The general idea is that once we have enough data to validate the namespace index we do so and then proceed to fetch only those labels that are not listed as being "free". By doing this I am seeing a total time reduction from about 4-5 seconds to 2-3 seconds for 24 NVDIMM modules each with 128K of label config area. Reviewed-by: Toshi Kani Signed-off-by: Alexander Duyck Signed-off-by: Dan Williams

nvdimm: Split label init out from the logic for getting config data

2018-10-12T15:39:24+00:00

This patch splits the initialization of the label data into two functions. One for doing the init, and another for reading the actual configuration data. The idea behind this is that by doing this we create a symmetry between the getting and setting of config data in that we have a function for both. In addition it will make it easier for us to identify the bits that are related to init versus the pieces that are a wrapper for reading data from the ACPI interface. So for example by splitting things out like this it becomes much more obvious that we were performing checks that weren't necessarily related to the set/get operations such as relying on ndd->data being present when the set and get ops should not care about a locally cached copy of the label area. Reviewed-by: Toshi Kani Signed-off-by: Alexander Duyck Signed-off-by: Dan Williams

nvdimm: Remove empty if statement

2018-10-12T15:39:15+00:00

This patch removes an empty statement from an if expression and promotes the else statement to the if expression with the expression logic reversed. I feel this is more readable as the empty statement can lead to issues if any additional logic was ever added. Reviewed-by: Toshi Kani Signed-off-by: Alexander Duyck Signed-off-by: Dan Williams

nvdimm: Clarify comment in sizeof_namespace_index

2018-10-12T15:39:10+00:00

When working on the label code I found it rather confusing to see several spots that reference a minimum label size of 256 while working with labels that are 128 bytes in size. This patch is meant to provide a clarification on one of the comments that was at the heart of the issue. Specifically for version 1.2 and later of the namespace specification the minimum label size is 256, prior to that the minimum label size was 128. So we should state that as such to avoid confusion. Reviewed-by: Toshi Kani Signed-off-by: Alexander Duyck Signed-off-by: Dan Williams

nvdimm: Sanity check labeloff

2018-10-12T15:38:53+00:00

This patch adds validation for the labeloff field in the indexes. Reviewed-by: Toshi Kani Signed-off-by: Alexander Duyck Signed-off-by: Dan Williams

libnvdimm, dimm: Maximize label transfer size

2018-10-11T03:54:16+00:00

Use kvzalloc() to bypass the arbitrary PAGE_SIZE limit of label transfer operations. Given the expense of calling into firmware, maximize the amount of label data we transfer per call to be up to the total label space if allowed by the firmware. Instead of limiting based on PAGE_SIZE we can instead simply limit the maximum size based on either the config_size int he case of the get operation, or the length of the write based on the set operation. On a system with 24 NVDIMM modules each with a config_size of 128K and a maximum transfer size of 64K - 4, this patch reduces the init time for the label data from around 24 seconds down to between 4-5 seconds. Reviewed-by: Toshi Kani Signed-off-by: Alexander Duyck Signed-off-by: Dan Williams