4 files changed, 55 insertions, 14 deletions

diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c
index 41aa1f01fc07..18a267d5073f 100644
--- a/drivers/nvdimm/btt.c
+++ b/drivers/nvdimm/btt.c
@@ -6,6 +6,7 @@
 #include <linux/highmem.h>
 #include <linux/debugfs.h>
 #include <linux/blkdev.h>
+#include <linux/pagemap.h>
 #include <linux/module.h>
 #include <linux/device.h>
 #include <linux/mutex.h>
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 48f0985ca8a0..3a777d0073b7 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -631,16 +631,14 @@ void nvdimm_check_and_set_ro(struct gendisk *disk)
 	struct nd_region *nd_region = to_nd_region(dev->parent);
 	int disk_ro = get_disk_ro(disk);
 
-	/*
-	 * Upgrade to read-only if the region is read-only preserve as
-	 * read-only if the disk is already read-only.
-	 */
-	if (disk_ro || nd_region->ro == disk_ro)
+	/* catch the disk up with the region ro state */
+	if (disk_ro == nd_region->ro)
 		return;
 
-	dev_info(dev, "%s read-only, marking %s read-only\n",
-			dev_name(&nd_region->dev), disk->disk_name);
-	set_disk_ro(disk, 1);
+	dev_info(dev, "%s read-%s, marking %s read-%s\n",
+		 dev_name(&nd_region->dev), nd_region->ro ? "only" : "write",
+		 disk->disk_name, nd_region->ro ? "only" : "write");
+	set_disk_ro(disk, nd_region->ro);
 }
 EXPORT_SYMBOL(nvdimm_check_and_set_ro);
 
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index b8a85bfb2e95..ed10a8b66068 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -8,6 +8,7 @@
  */
 
 #include <linux/blkdev.h>
+#include <linux/pagemap.h>
 #include <linux/hdreg.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
@@ -26,6 +27,7 @@
 #include <linux/mm.h>
 #include <asm/cacheflush.h>
 #include "pmem.h"
+#include "btt.h"
 #include "pfn.h"
 #include "nd.h"
 
@@ -585,7 +587,7 @@ static void nd_pmem_shutdown(struct device *dev)
 	nvdimm_flush(to_nd_region(dev->parent), NULL);
 }
 
-static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
+static void pmem_revalidate_poison(struct device *dev)
 {
 	struct nd_region *nd_region;
 	resource_size_t offset = 0, end_trunc = 0;
@@ -595,9 +597,6 @@ static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
 	struct range range;
 	struct kernfs_node *bb_state;
 
-	if (event != NVDIMM_REVALIDATE_POISON)
-		return;
-
 	if (is_nd_btt(dev)) {
 		struct nd_btt *nd_btt = to_nd_btt(dev);
 
@@ -635,6 +634,37 @@ static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
 		sysfs_notify_dirent(bb_state);
 }
 
+static void pmem_revalidate_region(struct device *dev)
+{
+	struct pmem_device *pmem;
+
+	if (is_nd_btt(dev)) {
+		struct nd_btt *nd_btt = to_nd_btt(dev);
+		struct btt *btt = nd_btt->btt;
+
+		nvdimm_check_and_set_ro(btt->btt_disk);
+		return;
+	}
+
+	pmem = dev_get_drvdata(dev);
+	nvdimm_check_and_set_ro(pmem->disk);
+}
+
+static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
+{
+	switch (event) {
+	case NVDIMM_REVALIDATE_POISON:
+		pmem_revalidate_poison(dev);
+		break;
+	case NVDIMM_REVALIDATE_REGION:
+		pmem_revalidate_region(dev);
+		break;
+	default:
+		dev_WARN_ONCE(dev, 1, "notify: unknown event: %d\n", event);
+		break;
+	}
+}
+
 MODULE_ALIAS("pmem");
 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index ef23119db574..9ccf3d608799 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -518,6 +518,12 @@ static ssize_t read_only_show(struct device *dev,
 	return sprintf(buf, "%d\n", nd_region->ro);
 }
 
+static int revalidate_read_only(struct device *dev, void *data)
+{
+	nd_device_notify(dev, NVDIMM_REVALIDATE_REGION);
+	return 0;
+}
+
 static ssize_t read_only_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t len)
 {
@@ -529,6 +535,7 @@ static ssize_t read_only_store(struct device *dev,
 		return rc;
 
 	nd_region->ro = ro;
+	device_for_each_child(dev, NULL, revalidate_read_only);
 	return len;
 }
 static DEVICE_ATTR_RW(read_only);
@@ -1239,6 +1246,11 @@ int nvdimm_has_flush(struct nd_region *nd_region)
 			|| !IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API))
 		return -ENXIO;
 
+	/* Test if an explicit flush function is defined */
+	if (test_bit(ND_REGION_ASYNC, &nd_region->flags) && nd_region->flush)
+		return 1;
+
+	/* Test if any flush hints for the region are available */
 	for (i = 0; i < nd_region->ndr_mappings; i++) {
 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 		struct nvdimm *nvdimm = nd_mapping->nvdimm;
@@ -1249,8 +1261,8 @@ int nvdimm_has_flush(struct nd_region *nd_region)
 	}
 
 	/*
-	 * The platform defines dimm devices without hints, assume
-	 * platform persistence mechanism like ADR
+	 * The platform defines dimm devices without hints nor explicit flush,
+	 * assume platform persistence mechanism like ADR
 	 */
 	return 0;
 }