[PATCH v5 1/4] powerpc/papr_scm: Fetch nvdimm health information from PHYP
Vaibhav Jain
vaibhav at linux.ibm.com
Wed Apr 1 01:32:26 AEDT 2020
Implement support for fetching nvdimm health information via
H_SCM_HEALTH hcall as documented in Ref[1]. The hcall returns a pair
of 64-bit big-endian integers which are then stored in 'struct
papr_scm_priv' and subsequently partially exposed to user-space via
newly introduced dimm specific attribute 'papr_flags'. Also a new asm
header named 'papr-scm.h' is added that describes the interface
between PHYP and guest kernel.
Following flags are reported via 'papr_flags' sysfs attribute contents
of which are space separated string flags indicating various nvdimm
states:
* "not_armed" : Indicating that nvdimm contents wont survive a power
cycle.
* "save_fail" : Indicating that nvdimm contents couldn't be flushed
during last shutdown event.
* "restore_fail": Indicating that nvdimm contents couldn't be restored
during dimm initialization.
* "encrypted" : Dimm contents are encrypted.
* "smart_notify": There is health event for the nvdimm.
* "scrubbed" : Indicating that contents of the nvdimm have been
scrubbed.
* "locked" : Indicating that nvdimm contents cant be modified
until next power cycle.
[1]: commit 58b278f568f0 ("powerpc: Provide initial documentation for
PAPR hcalls")
Signed-off-by: Vaibhav Jain <vaibhav at linux.ibm.com>
---
Changelog:
v4..v5 : None
v3..v4 : None
v2..v3 : Removed PAPR_SCM_DIMM_HEALTH_NON_CRITICAL as a condition for
NVDIMM unarmed [Aneesh]
v1..v2 : New patch in the series.
---
arch/powerpc/include/asm/papr_scm.h | 48 ++++++++++
arch/powerpc/platforms/pseries/papr_scm.c | 105 +++++++++++++++++++++-
2 files changed, 151 insertions(+), 2 deletions(-)
create mode 100644 arch/powerpc/include/asm/papr_scm.h
diff --git a/arch/powerpc/include/asm/papr_scm.h b/arch/powerpc/include/asm/papr_scm.h
new file mode 100644
index 000000000000..868d3360f56a
--- /dev/null
+++ b/arch/powerpc/include/asm/papr_scm.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Structures and defines needed to manage nvdimms for spapr guests.
+ */
+#ifndef _ASM_POWERPC_PAPR_SCM_H_
+#define _ASM_POWERPC_PAPR_SCM_H_
+
+#include <linux/types.h>
+#include <asm/bitsperlong.h>
+
+/* DIMM health bitmap bitmap indicators */
+/* SCM device is unable to persist memory contents */
+#define PAPR_SCM_DIMM_UNARMED PPC_BIT(0)
+/* SCM device failed to persist memory contents */
+#define PAPR_SCM_DIMM_SHUTDOWN_DIRTY PPC_BIT(1)
+/* SCM device contents are persisted from previous IPL */
+#define PAPR_SCM_DIMM_SHUTDOWN_CLEAN PPC_BIT(2)
+/* SCM device contents are not persisted from previous IPL */
+#define PAPR_SCM_DIMM_EMPTY PPC_BIT(3)
+/* SCM device memory life remaining is critically low */
+#define PAPR_SCM_DIMM_HEALTH_CRITICAL PPC_BIT(4)
+/* SCM device will be garded off next IPL due to failure */
+#define PAPR_SCM_DIMM_HEALTH_FATAL PPC_BIT(5)
+/* SCM contents cannot persist due to current platform health status */
+#define PAPR_SCM_DIMM_HEALTH_UNHEALTHY PPC_BIT(6)
+/* SCM device is unable to persist memory contents in certain conditions */
+#define PAPR_SCM_DIMM_HEALTH_NON_CRITICAL PPC_BIT(7)
+/* SCM device is encrypted */
+#define PAPR_SCM_DIMM_ENCRYPTED PPC_BIT(8)
+/* SCM device has been scrubbed and locked */
+#define PAPR_SCM_DIMM_SCRUBBED_AND_LOCKED PPC_BIT(9)
+
+/* Bits status indicators for health bitmap indicating unarmed dimm */
+#define PAPR_SCM_DIMM_UNARMED_MASK (PAPR_SCM_DIMM_UNARMED | \
+ PAPR_SCM_DIMM_HEALTH_UNHEALTHY)
+
+/* Bits status indicators for health bitmap indicating unflushed dimm */
+#define PAPR_SCM_DIMM_BAD_SHUTDOWN_MASK (PAPR_SCM_DIMM_SHUTDOWN_DIRTY)
+
+/* Bits status indicators for health bitmap indicating unrestored dimm */
+#define PAPR_SCM_DIMM_BAD_RESTORE_MASK (PAPR_SCM_DIMM_EMPTY)
+
+/* Bit status indicators for smart event notification */
+#define PAPR_SCM_DIMM_SMART_EVENT_MASK (PAPR_SCM_DIMM_HEALTH_CRITICAL | \
+ PAPR_SCM_DIMM_HEALTH_FATAL | \
+ PAPR_SCM_DIMM_HEALTH_UNHEALTHY)
+
+#endif
diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c
index 0b4467e378e5..aaf2e4ab1f75 100644
--- a/arch/powerpc/platforms/pseries/papr_scm.c
+++ b/arch/powerpc/platforms/pseries/papr_scm.c
@@ -14,6 +14,7 @@
#include <linux/delay.h>
#include <asm/plpar_wrappers.h>
+#include <asm/papr_scm.h>
#define BIND_ANY_ADDR (~0ul)
@@ -39,6 +40,13 @@ struct papr_scm_priv {
struct resource res;
struct nd_region *region;
struct nd_interleave_set nd_set;
+
+ /* Protect dimm data from concurrent access */
+ struct mutex dimm_mutex;
+
+ /* Health information for the dimm */
+ __be64 health_bitmap;
+ __be64 health_bitmap_valid;
};
static int drc_pmem_bind(struct papr_scm_priv *p)
@@ -144,6 +152,35 @@ static int drc_pmem_query_n_bind(struct papr_scm_priv *p)
return drc_pmem_bind(p);
}
+static int drc_pmem_query_health(struct papr_scm_priv *p)
+{
+ unsigned long ret[PLPAR_HCALL_BUFSIZE];
+ int64_t rc;
+
+ rc = plpar_hcall(H_SCM_HEALTH, ret, p->drc_index);
+ if (rc != H_SUCCESS) {
+ dev_err(&p->pdev->dev,
+ "Failed to query health information, Err:%lld\n", rc);
+ return -ENXIO;
+ }
+
+ /* Protect modifications to papr_scm_priv with the mutex */
+ rc = mutex_lock_interruptible(&p->dimm_mutex);
+ if (rc)
+ return rc;
+
+ /* Store the retrieved health information in dimm platform data */
+ p->health_bitmap = ret[0];
+ p->health_bitmap_valid = ret[1];
+
+ dev_dbg(&p->pdev->dev,
+ "Queried dimm health info. Bitmap:0x%016llx Mask:0x%016llx\n",
+ be64_to_cpu(p->health_bitmap),
+ be64_to_cpu(p->health_bitmap_valid));
+
+ mutex_unlock(&p->dimm_mutex);
+ return 0;
+}
static int papr_scm_meta_get(struct papr_scm_priv *p,
struct nd_cmd_get_config_data_hdr *hdr)
@@ -304,6 +341,67 @@ static inline int papr_scm_node(int node)
return min_node;
}
+static ssize_t papr_flags_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct nvdimm *dimm = to_nvdimm(dev);
+ struct papr_scm_priv *p = nvdimm_provider_data(dimm);
+ __be64 health;
+ int rc;
+
+ rc = drc_pmem_query_health(p);
+ if (rc)
+ return rc;
+
+ /* Protect against modifications to papr_scm_priv with the mutex */
+ rc = mutex_lock_interruptible(&p->dimm_mutex);
+ if (rc)
+ return rc;
+
+ health = p->health_bitmap & p->health_bitmap_valid;
+
+ /* Check for various masks in bitmap and set the buffer */
+ if (health & PAPR_SCM_DIMM_UNARMED_MASK)
+ rc += sprintf(buf, "not_armed ");
+
+ if (health & PAPR_SCM_DIMM_BAD_SHUTDOWN_MASK)
+ rc += sprintf(buf + rc, "save_fail ");
+
+ if (health & PAPR_SCM_DIMM_BAD_RESTORE_MASK)
+ rc += sprintf(buf + rc, "restore_fail ");
+
+ if (health & PAPR_SCM_DIMM_ENCRYPTED)
+ rc += sprintf(buf + rc, "encrypted ");
+
+ if (health & PAPR_SCM_DIMM_SMART_EVENT_MASK)
+ rc += sprintf(buf + rc, "smart_notify ");
+
+ if (health & PAPR_SCM_DIMM_SCRUBBED_AND_LOCKED)
+ rc += sprintf(buf + rc, "scrubbed locked ");
+
+ if (rc > 0)
+ rc += sprintf(buf + rc, "\n");
+
+ mutex_unlock(&p->dimm_mutex);
+ return rc;
+}
+DEVICE_ATTR_RO(papr_flags);
+
+/* papr_scm specific dimm attributes */
+static struct attribute *papr_scm_nd_attributes[] = {
+ &dev_attr_papr_flags.attr,
+ NULL,
+};
+
+static struct attribute_group papr_scm_nd_attribute_group = {
+ .attrs = papr_scm_nd_attributes,
+};
+
+static const struct attribute_group *papr_scm_dimm_attr_groups[] = {
+ &papr_scm_nd_attribute_group,
+ NULL,
+};
+
static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
{
struct device *dev = &p->pdev->dev;
@@ -330,8 +428,8 @@ static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
dimm_flags = 0;
set_bit(NDD_ALIASING, &dimm_flags);
- p->nvdimm = nvdimm_create(p->bus, p, NULL, dimm_flags,
- PAPR_SCM_DIMM_CMD_MASK, 0, NULL);
+ p->nvdimm = nvdimm_create(p->bus, p, papr_scm_dimm_attr_groups,
+ dimm_flags, PAPR_SCM_DIMM_CMD_MASK, 0, NULL);
if (!p->nvdimm) {
dev_err(dev, "Error creating DIMM object for %pOF\n", p->dn);
goto err;
@@ -415,6 +513,9 @@ static int papr_scm_probe(struct platform_device *pdev)
if (!p)
return -ENOMEM;
+ /* Initialize the dimm mutex */
+ mutex_init(&p->dimm_mutex);
+
/* optional DT properties */
of_property_read_u32(dn, "ibm,metadata-size", &metadata_size);
--
2.25.1
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