commit d4f323672aa63713b7ca26da418f66cc30d3a41a
author Dan Williams <dan.j.williams@intel.com> Thu Mar 03 16:08:54 2016 -0800
committer Dan Williams <dan.j.williams@intel.com> Sat Mar 05 18:06:14 2016 -0800
tree c073dd799eab97ed7b6e7e04a94c16e793361285
parent 07accfa9d1a8bac8262f6d24a94a54d2d1f35149

nfit, libnvdimm: clear poison command support

Add the boiler-plate for a 'clear error' command based on section
9.20.7.6 "Function Index 4 - Clear Uncorrectable Error" from the ACPI
6.1 specification, and add a reference implementation in nfit_test.

Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/acpi/nfit.c

diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index 0def4eb..c067d74 100644
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -87,6 +87,7 @@
 
 static int xlat_status(void *buf, unsigned int cmd)
 {
+	struct nd_cmd_clear_error *clear_err;
 	struct nd_cmd_ars_status *ars_status;
 	struct nd_cmd_ars_start *ars_start;
 	struct nd_cmd_ars_cap *ars_cap;
@@ -149,6 +150,15 @@
 		if (ars_status->status >> 16)
 			return -EIO;
 		break;
+	case ND_CMD_CLEAR_ERROR:
+		clear_err = buf;
+		if (clear_err->status & 0xffff)
+			return -EIO;
+		if (!clear_err->cleared)
+			return -EIO;
+		if (clear_err->length > clear_err->cleared)
+			return clear_err->cleared;
+		break;
 	default:
 		break;
 	}
@@ -1002,7 +1012,7 @@
 	if (!adev)
 		return;
 
-	for (i = ND_CMD_ARS_CAP; i <= ND_CMD_ARS_STATUS; i++)
+	for (i = ND_CMD_ARS_CAP; i <= ND_CMD_CLEAR_ERROR; i++)
 		if (acpi_check_dsm(adev->handle, uuid, 1, 1ULL << i))
 			set_bit(i, &nd_desc->dsm_mask);
 }

drivers/nvdimm/bus.c

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 2e9ac22..cb6fd64 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -421,6 +421,12 @@
 		.out_num = 3,
 		.out_sizes = { 4, 4, UINT_MAX, },
 	},
+	[ND_CMD_CLEAR_ERROR] = {
+		.in_num = 2,
+		.in_sizes = { 8, 8, },
+		.out_num = 3,
+		.out_sizes = { 4, 4, 8, },
+	},
 };
 
 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
@@ -489,6 +495,13 @@
 	} while (true);
 }
 
+static int pmem_active(struct device *dev, void *data)
+{
+	if (is_nd_pmem(dev) && dev->driver)
+		return -EBUSY;
+	return 0;
+}
+
 /* set_config requires an idle interleave set */
 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
 		struct nvdimm *nvdimm, unsigned int cmd)
@@ -503,6 +516,11 @@
 			return rc;
 	}
 
+	/* require clear error to go through the pmem driver */
+	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
+		return device_for_each_child(&nvdimm_bus->dev, NULL,
+				pmem_active);
+
 	if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
 		return 0;
 
@@ -551,6 +569,7 @@
 		case ND_CMD_VENDOR:
 		case ND_CMD_SET_CONFIG_DATA:
 		case ND_CMD_ARS_START:
+		case ND_CMD_CLEAR_ERROR:
 			dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n",
 					nvdimm ? nvdimm_cmd_name(cmd)
 					: nvdimm_bus_cmd_name(cmd));