libnvdimm: nd_region flush callback support
This patch adds functionality to perform flush from guest
to host over VIRTIO. We are registering a callback based
on 'nd_region' type. virtio_pmem driver requires this special
flush function. For rest of the region types we are registering
existing flush function. Report error returned by host fsync
failure to userspace.
Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 03d5c3a..e13100f 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -11,6 +11,7 @@
#include <linux/types.h>
#include <linux/uuid.h>
#include <linux/spinlock.h>
+#include <linux/bio.h>
struct badrange_entry {
u64 start;
@@ -57,6 +58,9 @@ enum {
*/
ND_REGION_PERSIST_MEMCTRL = 2,
+ /* Platform provides asynchronous flush mechanism */
+ ND_REGION_ASYNC = 3,
+
/* mark newly adjusted resources as requiring a label update */
DPA_RESOURCE_ADJUSTED = 1 << 0,
};
@@ -113,6 +117,7 @@ struct nd_mapping_desc {
int position;
};
+struct nd_region;
struct nd_region_desc {
struct resource *res;
struct nd_mapping_desc *mapping;
@@ -125,6 +130,7 @@ struct nd_region_desc {
int target_node;
unsigned long flags;
struct device_node *of_node;
+ int (*flush)(struct nd_region *nd_region, struct bio *bio);
};
struct device;
@@ -252,7 +258,8 @@ unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr);
unsigned int nd_region_acquire_lane(struct nd_region *nd_region);
void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane);
u64 nd_fletcher64(void *addr, size_t len, bool le);
-void nvdimm_flush(struct nd_region *nd_region);
+int nvdimm_flush(struct nd_region *nd_region, struct bio *bio);
+int generic_nvdimm_flush(struct nd_region *nd_region);
int nvdimm_has_flush(struct nd_region *nd_region);
int nvdimm_has_cache(struct nd_region *nd_region);
int nvdimm_in_overwrite(struct nvdimm *nvdimm);