Commit d35f18b5 authored by Vaibhav Jain's avatar Vaibhav Jain Committed by Dan Williams
Browse files

powerpc/papr_scm: Implement support for PAPR_PDSM_HEALTH 



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'.

Signed-off-by: default avatarVaibhav Jain <vaibhav@linux.ibm.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20200615124407.32596-7-vaibhav@linux.ibm.com


Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent f517f792

arch/powerpc/include/uapi/asm/papr_pdsm.h

+37 −0
Original line number Diff line number Diff line
@@ -66,17 +66,54 @@ 
#define ND_PDSM_HDR_SIZE \

	(sizeof(struct nd_pkg_pdsm) - ND_PDSM_PAYLOAD_MAX_SIZE)



/* 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.

 *

 * extension_flags	: Any extension fields present in the struct.

 * 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 {

	union {

		struct {

			__u32 extension_flags;

			__u8 dimm_unarmed;

			__u8 dimm_bad_shutdown;

			__u8 dimm_bad_restore;

			__u8 dimm_scrubbed;

			__u8 dimm_locked;

			__u8 dimm_encrypted;

			__u16 dimm_health;

		};

		__u8 buf[ND_PDSM_PAYLOAD_MAX_SIZE];

	};

};



/*

 * Methods to be embedded in ND_CMD_CALL request. These are sent to the kernel

 * via 'nd_cmd_pkg.nd_command' member of the ioctl struct

 */

enum papr_pdsm {

	PAPR_PDSM_MIN = 0x0,

	PAPR_PDSM_HEALTH,

	PAPR_PDSM_MAX,

};



/* Maximal union that can hold all possible payload types */

union nd_pdsm_payload {

	struct nd_papr_pdsm_health health;

	__u8 buf[ND_PDSM_PAYLOAD_MAX_SIZE];

} __packed;

arch/powerpc/platforms/pseries/papr_scm.c

+51 −0
Original line number Diff line number Diff line
@@ -416,6 +416,52 @@ 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,

			    union nd_pdsm_payload *payload)

{

	int rc;



	/* 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 */

	payload->health = (struct nd_papr_pdsm_health) {

		.extension_flags = 0,

		.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_scrubbed = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),

		.dimm_locked = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),

		.dimm_encrypted = !!(p->health_bitmap & PAPR_PMEM_ENCRYPTED),

		.dimm_health = PAPR_PDSM_DIMM_HEALTHY,

	};



	/* Update field dimm_health based on health_bitmap flags */

	if (p->health_bitmap & PAPR_PMEM_HEALTH_FATAL)

		payload->health.dimm_health = PAPR_PDSM_DIMM_FATAL;

	else if (p->health_bitmap & PAPR_PMEM_HEALTH_CRITICAL)

		payload->health.dimm_health = PAPR_PDSM_DIMM_CRITICAL;

	else if (p->health_bitmap & PAPR_PMEM_HEALTH_UNHEALTHY)

		payload->health.dimm_health = PAPR_PDSM_DIMM_UNHEALTHY;



	/* struct populated hence can release the mutex now */

	mutex_unlock(&p->health_mutex);

	rc = sizeof(struct nd_papr_pdsm_health);



out:

	return rc;

}



/*

 * 'struct pdsm_cmd_desc'

 * Identifies supported PDSMs' expected length of in/out payloads
@@ -444,6 +490,11 @@ static const struct pdsm_cmd_desc __pdsm_cmd_descriptors[] = { 
	},

	/* New PDSM command descriptors to be added below */



	[PAPR_PDSM_HEALTH] = {

		.size_in = 0,

		.size_out = sizeof(struct nd_papr_pdsm_health),

		.service = papr_pdsm_health,

	},

	/* Empty */

	[PAPR_PDSM_MAX] = {

		.size_in = 0,