libnvdimm, pmem: clear poison on write
If a write is directed at a known bad block perform the following:
1/ write the data
2/ send a clear poison command
3/ invalidate the poison out of the cache hierarchy
Cc: <x86@kernel.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index cb6fd64..3355748 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -159,6 +159,52 @@
}
EXPORT_SYMBOL_GPL(nvdimm_region_notify);
+long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
+ unsigned int len)
+{
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct nvdimm_bus_descriptor *nd_desc;
+ struct nd_cmd_clear_error clear_err;
+ struct nd_cmd_ars_cap ars_cap;
+ u32 clear_err_unit, mask;
+ int cmd_rc, rc;
+
+ if (!nvdimm_bus)
+ return -ENXIO;
+
+ nd_desc = nvdimm_bus->nd_desc;
+ if (!nd_desc->ndctl)
+ return -ENXIO;
+
+ memset(&ars_cap, 0, sizeof(ars_cap));
+ ars_cap.address = phys;
+ ars_cap.length = len;
+ rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
+ sizeof(ars_cap), &cmd_rc);
+ if (rc < 0)
+ return rc;
+ if (cmd_rc < 0)
+ return cmd_rc;
+ clear_err_unit = ars_cap.clear_err_unit;
+ if (!clear_err_unit || !is_power_of_2(clear_err_unit))
+ return -ENXIO;
+
+ mask = clear_err_unit - 1;
+ if ((phys | len) & mask)
+ return -ENXIO;
+ memset(&clear_err, 0, sizeof(clear_err));
+ clear_err.address = phys;
+ clear_err.length = len;
+ rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
+ sizeof(clear_err), &cmd_rc);
+ if (rc < 0)
+ return rc;
+ if (cmd_rc < 0)
+ return cmd_rc;
+ return clear_err.cleared;
+}
+EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
+
static struct bus_type nvdimm_bus_type = {
.name = "nd",
.uevent = nvdimm_bus_uevent,