4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Bhavesh Davda <bhavesh.davda@xxxxxxxxxx>
[ Upstream commit 7ed8ce1c5fc7cf25b3602c73bef897a3466a6645 ]
negotiate_mq should happen in all cases of a new VBD being discovered by
xen-blkfront, whether called through _probe() or a hot-attached new VBD
from dom-0 via xenstore. Otherwise, hot-attached new VBDs are left
configured without multi-queue.
Signed-off-by: Bhavesh Davda <bhavesh.davda@xxxxxxxxxx>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/block/xen-blkfront.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -262,6 +262,7 @@ static DEFINE_SPINLOCK(minor_lock);
static int blkfront_setup_indirect(struct blkfront_ring_info *rinfo);
static void blkfront_gather_backend_features(struct blkfront_info *info);
+static int negotiate_mq(struct blkfront_info *info);
static int get_id_from_freelist(struct blkfront_ring_info *rinfo)
{
@@ -1774,11 +1775,18 @@ static int talk_to_blkback(struct xenbus
unsigned int i, max_page_order;
unsigned int ring_page_order;
+ if (!info)
+ return -ENODEV;
+
max_page_order = xenbus_read_unsigned(info->xbdev->otherend,
"max-ring-page-order", 0);
ring_page_order = min(xen_blkif_max_ring_order, max_page_order);
info->nr_ring_pages = 1 << ring_page_order;
+ err = negotiate_mq(info);
+ if (err)
+ goto destroy_blkring;
+
for (i = 0; i < info->nr_rings; i++) {
struct blkfront_ring_info *rinfo = &info->rinfo[i];
@@ -1978,11 +1986,6 @@ static int blkfront_probe(struct xenbus_
}
info->xbdev = dev;
- err = negotiate_mq(info);
- if (err) {
- kfree(info);
- return err;
- }
mutex_init(&info->mutex);
info->vdevice = vdevice;
@@ -2099,10 +2102,6 @@ static int blkfront_resume(struct xenbus
blkif_free(info, info->connected == BLKIF_STATE_CONNECTED);
- err = negotiate_mq(info);
- if (err)
- return err;
-
err = talk_to_blkback(dev, info);
if (!err)
blk_mq_update_nr_hw_queues(&info->tag_set, info->nr_rings);
