mirror of https://github.com/torvalds/linux.git
de21e1377c
Persistent memory devices like NVDIMMs can loose cached writes in case something prevents flush on power-fail. Such situations are termed as dirty shutdown and are exposed to applications as last-shutdown-state (LSS) flag and a dirty-shutdown-counter(DSC) as described at [1]. The latter being useful in conditions where multiple applications want to detect a dirty shutdown event without racing with one another. PAPR-NVDIMMs have so far only exposed LSS style flags to indicate a dirty-shutdown-state. This patch further adds support for DSC via the "ibm,persistence-failed-count" device tree property of an NVDIMM. This property is a monotonic increasing 64-bit counter thats an indication of number of times an NVDIMM has encountered a dirty-shutdown event causing persistence loss. Since this value is not expected to change after system-boot hence papr_scm reads & caches its value during NVDIMM probe and exposes it as a PAPR sysfs attributed named 'dirty_shutdown' to match the name of similarly named NFIT sysfs attribute. Also this value is available to libnvdimm via PAPR_PDSM_HEALTH payload. 'struct nd_papr_pdsm_health' has been extended to add a new member called 'dimm_dsc' presence of which is indicated by the newly introduced PDSM_DIMM_DSC_VALID flag. References: [1] https://pmem.io/documents/Dirty_Shutdown_Handling-V1.0.pdf Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210624080621.252038-1-vaibhav@linux.ibm.com |
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| .. | ||
| Kbuild | ||
| auxvec.h | ||
| bitsperlong.h | ||
| bootx.h | ||
| bpf_perf_event.h | ||
| byteorder.h | ||
| cputable.h | ||
| eeh.h | ||
| elf.h | ||
| epapr_hcalls.h | ||
| errno.h | ||
| fcntl.h | ||
| ioctl.h | ||
| ioctls.h | ||
| ipcbuf.h | ||
| kvm.h | ||
| kvm_para.h | ||
| mman.h | ||
| msgbuf.h | ||
| nvram.h | ||
| opal-prd.h | ||
| papr_pdsm.h | ||
| perf_event.h | ||
| perf_regs.h | ||
| posix_types.h | ||
| ps3fb.h | ||
| ptrace.h | ||
| sembuf.h | ||
| setup.h | ||
| shmbuf.h | ||
| sigcontext.h | ||
| signal.h | ||
| socket.h | ||
| spu_info.h | ||
| stat.h | ||
| swab.h | ||
| termbits.h | ||
| termios.h | ||
| tm.h | ||
| types.h | ||
| ucontext.h | ||
| unistd.h | ||
| vas-api.h | ||