libnvdimm, nfit: add interleave-set state-tracking infrastructure
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>
Showing
Please register or sign in to comment