Ira Weiny <ira.we...@intel.com> writes: > On Fri, Jun 05, 2020 at 05:11:36AM +0530, Vaibhav Jain wrote: >> This patch implements support for PDSM request 'PAPR_PDSM_HEALTH' >> that returns a newly introduced 'struct nd_papr_pdsm_health' instance >> containing dimm health information back to user space in response to >> ND_CMD_CALL. This functionality is implemented in newly introduced >> papr_pdsm_health() that queries the nvdimm health information and >> then copies this information to the package payload whose layout is >> defined by 'struct nd_papr_pdsm_health'. >> >> Cc: "Aneesh Kumar K . V" <aneesh.ku...@linux.ibm.com> >> Cc: Dan Williams <dan.j.willi...@intel.com> >> Cc: Michael Ellerman <m...@ellerman.id.au> >> Cc: Ira Weiny <ira.we...@intel.com> >> Signed-off-by: Vaibhav Jain <vaib...@linux.ibm.com> >> --- >> Changelog: >> >> v9..v10: >> * Removed code in papr_pdsm_health that performed validation on pdsm >> payload version and corrosponding struct and defines used for >> validation of payload version. >> * Dropped usage of struct papr_pdsm_health in 'struct >> papr_scm_priv'. Instead papr_psdm_health() now uses >> 'papr_scm_priv.health_bitmap' to populate the pdsm payload. >> * Above change also fixes the problem where this patch was removing >> the code that was previously introduced in this patch-series. >> [ Ira ] >> * Introduced a new def ND_PDSM_ENVELOPE_HDR_SIZE that indicates the >> space allocated to 'struct nd_pdsm_cmd_pkg' fields except 'struct >> nd_cmd_pkg'. This def is useful in validating payload sizes. >> * Reworked papr_pdsm_health() to enforce a specific payload size for >> 'PAPR_PDSM_HEALTH' pdsm request. >> >> Resend: >> * Added ack from Aneesh. >> >> v8..v9: >> * s/PAPR_SCM_PDSM_HEALTH/PAPR_PDSM_HEALTH/g [ Dan , Aneesh ] >> * s/PAPR_SCM_PSDM_DIMM_*/PAPR_PDSM_DIMM_*/g >> * Renamed papr_scm_get_health() to papr_psdm_health() >> * Updated patch description to replace papr-scm dimm with nvdimm. >> >> v7..v8: >> * None >> >> Resend: >> * None >> >> v6..v7: >> * Updated flags_show() to use seq_buf_printf(). [Mpe] >> * Updated papr_scm_get_health() to use newly introduced >> __drc_pmem_query_health() bypassing the cache [Mpe]. >> >> v5..v6: >> * Added attribute '__packed' to 'struct nd_papr_pdsm_health_v1' to >> gaurd against possibility of different compilers adding different >> paddings to the struct [ Dan Williams ] >> >> * Updated 'struct nd_papr_pdsm_health_v1' to use __u8 instead of >> 'bool' and also updated drc_pmem_query_health() to take this into >> account. [ Dan Williams ] >> >> v4..v5: >> * None >> >> v3..v4: >> * Call the DSM_PAPR_SCM_HEALTH service function from >> papr_scm_service_dsm() instead of papr_scm_ndctl(). [Aneesh] >> >> v2..v3: >> * Updated struct nd_papr_scm_dimm_health_stat_v1 to use '__xx' types >> as its exported to the userspace [Aneesh] >> * Changed the constants DSM_PAPR_SCM_DIMM_XX indicating dimm health >> from enum to #defines [Aneesh] >> >> v1..v2: >> * New patch in the series >> --- >> arch/powerpc/include/uapi/asm/papr_pdsm.h | 33 +++++++++++ >> arch/powerpc/platforms/pseries/papr_scm.c | 70 +++++++++++++++++++++++ >> 2 files changed, 103 insertions(+) >> >> diff --git a/arch/powerpc/include/uapi/asm/papr_pdsm.h >> b/arch/powerpc/include/uapi/asm/papr_pdsm.h >> index 8b1a4f8fa316..c4c990ede5d4 100644 >> --- a/arch/powerpc/include/uapi/asm/papr_pdsm.h >> +++ b/arch/powerpc/include/uapi/asm/papr_pdsm.h >> @@ -71,12 +71,17 @@ struct nd_pdsm_cmd_pkg { >> __u8 payload[]; /* In/Out: Sub-cmd data buffer */ >> } __packed; >> >> +/* Calculate size used by the pdsm header fields minus 'struct nd_cmd_pkg' >> */ >> +#define ND_PDSM_ENVELOPE_HDR_SIZE \ >> + (sizeof(struct nd_pdsm_cmd_pkg) - sizeof(struct nd_cmd_pkg)) >> + [ ] > > This is kind of a weird name for this. > > Isn't this just the ND PDSM header size? What is 'envelope' mean > here? Was referring to 'nd_cmd_pkg' envelop here. But yes removing 'ENVELOPE' should make it more concise. Have already done this in v11 of this patch.
> >> /* >> * Methods to be embedded in ND_CMD_CALL request. These are sent to the >> kernel >> * via 'nd_pdsm_cmd_pkg.hdr.nd_command' member of the ioctl struct >> */ >> enum papr_pdsm { >> PAPR_PDSM_MIN = 0x0, >> + PAPR_PDSM_HEALTH, >> PAPR_PDSM_MAX, >> }; >> >> @@ -95,4 +100,32 @@ static inline void *pdsm_cmd_to_payload(struct >> nd_pdsm_cmd_pkg *pcmd) >> return (void *)(pcmd->payload); >> } >> >> +/* Various nvdimm health indicators */ >> +#define PAPR_PDSM_DIMM_HEALTHY 0 >> +#define PAPR_PDSM_DIMM_UNHEALTHY 1 >> +#define PAPR_PDSM_DIMM_CRITICAL 2 >> +#define PAPR_PDSM_DIMM_FATAL 3 >> + >> +/* >> + * Struct exchanged between kernel & ndctl in for PAPR_PDSM_HEALTH >> + * Various flags indicate the health status of the dimm. >> + * >> + * dimm_unarmed : Dimm not armed. So contents wont persist. >> + * dimm_bad_shutdown : Previous shutdown did not persist contents. >> + * dimm_bad_restore : Contents from previous shutdown werent restored. >> + * dimm_scrubbed : Contents of the dimm have been scrubbed. >> + * dimm_locked : Contents of the dimm cant be modified until >> CEC reboot >> + * dimm_encrypted : Contents of dimm are encrypted. >> + * dimm_health : Dimm health indicator. One of >> PAPR_PDSM_DIMM_XXXX >> + */ >> +struct nd_papr_pdsm_health { >> + __u8 dimm_unarmed; >> + __u8 dimm_bad_shutdown; >> + __u8 dimm_bad_restore; >> + __u8 dimm_scrubbed; >> + __u8 dimm_locked; >> + __u8 dimm_encrypted; >> + __u16 dimm_health; >> +} __packed; >> + >> #endif /* _UAPI_ASM_POWERPC_PAPR_PDSM_H_ */ >> diff --git a/arch/powerpc/platforms/pseries/papr_scm.c >> b/arch/powerpc/platforms/pseries/papr_scm.c >> index 05eb56ecab5e..984942be24c1 100644 >> --- a/arch/powerpc/platforms/pseries/papr_scm.c >> +++ b/arch/powerpc/platforms/pseries/papr_scm.c >> @@ -421,6 +421,72 @@ static int is_cmd_valid(struct nvdimm *nvdimm, unsigned >> int cmd, void *buf, >> return 0; >> } >> >> +/* Fetch the DIMM health info and populate it in provided package. */ >> +static int papr_pdsm_health(struct papr_scm_priv *p, >> + struct nd_pdsm_cmd_pkg *pkg) >> +{ >> + int rc; >> + struct nd_papr_pdsm_health health = { 0 }; >> + u16 copysize = sizeof(struct nd_papr_pdsm_health); >> + u16 payload_size = pkg->hdr.nd_size_out - ND_PDSM_ENVELOPE_HDR_SIZE; >> + >> + /* Ensure correct payload size that can hold struct nd_papr_pdsm_health >> */ >> + if (payload_size != copysize) { >> + dev_dbg(&p->pdev->dev, >> + "Unexpected payload-size (%u). Expected (%u)", >> + pkg->hdr.nd_size_out, copysize); >> + rc = -ENOSPC; >> + goto out; >> + } >> + >> + /* Ensure dimm health mutex is taken preventing concurrent access */ >> + rc = mutex_lock_interruptible(&p->health_mutex); >> + if (rc) >> + goto out; >> + >> + /* Always fetch upto date dimm health data ignoring cached values */ >> + rc = __drc_pmem_query_health(p); >> + if (rc) { >> + mutex_unlock(&p->health_mutex); >> + goto out; >> + } >> + >> + /* update health struct with various flags derived from health bitmap */ >> + health = (struct nd_papr_pdsm_health) { >> + .dimm_unarmed = p->health_bitmap & PAPR_PMEM_UNARMED_MASK, >> + .dimm_bad_shutdown = p->health_bitmap & >> PAPR_PMEM_BAD_SHUTDOWN_MASK, >> + .dimm_bad_restore = p->health_bitmap & >> PAPR_PMEM_BAD_RESTORE_MASK, >> + .dimm_encrypted = p->health_bitmap & PAPR_PMEM_ENCRYPTED, >> + .dimm_locked = p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED, >> + .dimm_scrubbed = p->health_bitmap & >> PAPR_PMEM_SCRUBBED_AND_LOCKED, > > Are you sure these work? These are not assignments to a bool so I don't think > gcc will do what you want here. Yeah, somehow this slipped by and didnt show up in my tests. I checked the assembly dump and seems GCC was silently skipping initializing these fields without making any noise. Have rectified this in v11 by changing these designated initilizers to .dimm_locked = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED) Thanks for catching this. ~ Vaibhav > > Ira > >> + .dimm_health = PAPR_PDSM_DIMM_HEALTHY, >> + }; >> + >> + /* Update field dimm_health based on health_bitmap flags */ >> + if (p->health_bitmap & PAPR_PMEM_HEALTH_FATAL) >> + health.dimm_health = PAPR_PDSM_DIMM_FATAL; >> + else if (p->health_bitmap & PAPR_PMEM_HEALTH_CRITICAL) >> + health.dimm_health = PAPR_PDSM_DIMM_CRITICAL; >> + else if (p->health_bitmap & PAPR_PMEM_HEALTH_UNHEALTHY) >> + health.dimm_health = PAPR_PDSM_DIMM_UNHEALTHY; >> + >> + /* struct populated hence can release the mutex now */ >> + mutex_unlock(&p->health_mutex); >> + >> + dev_dbg(&p->pdev->dev, "Copying payload size=%u\n", copysize); >> + >> + /* Copy the health struct to the payload */ >> + memcpy(pdsm_cmd_to_payload(pkg), &health, copysize); >> + >> + /* Update fw size including size of struct nd_pdsm_cmd_pkg fields */ >> + pkg->hdr.nd_fw_size = copysize + ND_PDSM_ENVELOPE_HDR_SIZE; >> + >> +out: >> + dev_dbg(&p->pdev->dev, "completion code = %d\n", rc); >> + >> + return rc; >> +} >> + >> /* >> * For a given pdsm request call an appropriate service function. >> * Note: Use 'nd_pdsm_cmd_pkg.cmd_status to report psdm servicing errors. >> Hence >> @@ -435,6 +501,10 @@ static void papr_scm_service_pdsm(struct papr_scm_priv >> *p, >> >> /* Call pdsm service function */ >> switch (pdsm) { >> + case PAPR_PDSM_HEALTH: >> + pkg->cmd_status = papr_pdsm_health(p, pkg); >> + break; >> + >> default: >> dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Unsupported PDSM request\n", >> pdsm); >> -- >> 2.26.2 >> -- Cheers ~ Vaibhav