[RFC v2 2/2] pmem: device flush over VIRTIO

From: Pankaj Gupta
Date: Wed Apr 25 2018 - 07:24:55 EST


This patch adds functionality to perform
flush from guest to hosy over VIRTIO
when 'ND_REGION_VIRTIO'flag is set on
nd_negion. Flag is set by 'virtio-pmem'
driver.

Signed-off-by: Pankaj Gupta <pagupta@xxxxxxxxxx>
---
drivers/nvdimm/region_devs.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index a612be6..6c6454e 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -20,6 +20,7 @@
#include <linux/nd.h>
#include "nd-core.h"
#include "nd.h"
+#include <linux/virtio_pmem.h>

/*
* For readq() and writeq() on 32-bit builds, the hi-lo, lo-hi order is
@@ -1074,6 +1075,12 @@ void nvdimm_flush(struct nd_region *nd_region)
struct nd_region_data *ndrd = dev_get_drvdata(&nd_region->dev);
int i, idx;

+ /* call PV device flush */
+ if (test_bit(ND_REGION_VIRTIO, &nd_region->flags)) {
+ virtio_pmem_flush(&nd_region->dev);
+ return;
+ }
+
/*
* Try to encourage some diversity in flush hint addresses
* across cpus assuming a limited number of flush hints.
--
2.9.3