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

[Dave Jiang]

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.ji...@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: