[NDCTL PATCH] cxl/region: Add -f option for disable-region

[Dave Jiang <dave.jiang@intel.com>]

The current operation for disable_region does not check if the memory
covered by a region is online before attempting to disable the cxl region.
Provide a -f option for the region to force offlining of currently online
memory before disabling the region. Also add a check to fail the operation
entirely if the memory is non-movable.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
 Documentation/cxl/cxl-disable-region.txt |    5 +++
 cxl/region.c                             |   49 +++++++++++++++++++++++++++++-
 2 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/Documentation/cxl/cxl-disable-region.txt b/Documentation/cxl/cxl-disable-region.txt
index 6a39aee6ea69..1778ec3a0f3f 100644
--- a/Documentation/cxl/cxl-disable-region.txt
+++ b/Documentation/cxl/cxl-disable-region.txt
@@ -25,6 +25,11 @@ OPTIONS
 -------
 include::bus-option.txt[]
 
+-f::
+--force::
+	Force offline of memory if they are online before disabling the active
+	region. This does not allow offline of unmovable memory.
+
 include::decoder-option.txt[]
 
 include::debug-option.txt[]
diff --git a/cxl/region.c b/cxl/region.c
index bcd703956207..79a5fb81c257 100644
--- a/cxl/region.c
+++ b/cxl/region.c
@@ -14,6 +14,7 @@
 #include <util/parse-options.h>
 #include <ccan/minmax/minmax.h>
 #include <ccan/short_types/short_types.h>
+#include <daxctl/libdaxctl.h>
 
 #include "filter.h"
 #include "json.h"
@@ -95,6 +96,8 @@ static const struct option enable_options[] = {
 
 static const struct option disable_options[] = {
 	BASE_OPTIONS(),
+	OPT_BOOLEAN('f', "force", &param.force,
+		    "disable region even if memory currently online"),
 	OPT_END(),
 };
 
@@ -789,13 +792,57 @@ static int destroy_region(struct cxl_region *region)
 	return cxl_region_delete(region);
 }
 
+static int disable_region(struct cxl_region *region)
+{
+	const char *devname = cxl_region_get_devname(region);
+	struct daxctl_region *dax_region;
+	struct daxctl_memory *mem;
+	struct daxctl_dev *dev;
+	int rc;
+
+	dax_region = cxl_region_get_daxctl_region(region);
+	if (!dax_region)
+		goto out;
+
+	daxctl_dev_foreach(dax_region, dev) {
+		mem = daxctl_dev_get_memory(dev);
+		if (!mem)
+			return -ENXIO;
+
+		if (daxctl_memory_online_no_movable(mem)) {
+			log_err(&rl, "%s: memory unmovable for %s\n",
+					devname,
+					daxctl_dev_get_devname(dev));
+			return -EPERM;
+		}
+
+		/*
+		 * If memory is still online and user wants to force it, attempt
+		 * to offline it.
+		 */
+		if (daxctl_memory_is_online(mem) && param.force) {
+			rc = daxctl_memory_offline(mem);
+			if (rc) {
+				log_err(&rl, "%s: unable to offline %s: %s\n",
+					devname,
+					daxctl_dev_get_devname(dev),
+					strerror(abs(rc)));
+				return rc;
+			}
+		}
+	}
+
+out:
+	return cxl_region_disable(region);
+}
+
 static int do_region_xable(struct cxl_region *region, enum region_actions action)
 {
 	switch (action) {
 	case ACTION_ENABLE:
 		return cxl_region_enable(region);
 	case ACTION_DISABLE:
-		return cxl_region_disable(region);
+		return disable_region(region);
 	case ACTION_DESTROY:
 		return destroy_region(region);
 	default: