Commit 47cbd598 authored by Juergen Gross's avatar Juergen Gross
Browse files

xen/blkfront: use xenbus_setup_ring() and xenbus_teardown_ring() 



Simplify blkfront's ring creation and removal via xenbus_setup_ring()
and xenbus_teardown_ring().

Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: default avatarRoger Pau Monné <roger.pau@citrix.com>
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
parent 7050096d

drivers/block/xen-blkfront.c

+8 −29
Original line number Diff line number Diff line
@@ -1280,15 +1280,8 @@ static void blkif_free_ring(struct blkfront_ring_info *rinfo) 
	flush_work(&rinfo->work);



	/* Free resources associated with old device channel. */

	for (i = 0; i < info->nr_ring_pages; i++) {

		if (rinfo->ring_ref[i] != INVALID_GRANT_REF) {

			gnttab_end_foreign_access(rinfo->ring_ref[i], 0);

			rinfo->ring_ref[i] = INVALID_GRANT_REF;

		}

	}

	free_pages_exact(rinfo->ring.sring,

			 info->nr_ring_pages * XEN_PAGE_SIZE);

	rinfo->ring.sring = NULL;

	xenbus_teardown_ring((void **)&rinfo->ring.sring, info->nr_ring_pages,

			     rinfo->ring_ref);



	if (rinfo->irq)

		unbind_from_irqhandler(rinfo->irq, rinfo);
@@ -1679,30 +1672,16 @@ static int setup_blkring(struct xenbus_device *dev, 
			 struct blkfront_ring_info *rinfo)

{

	struct blkif_sring *sring;

	int err, i;

	int err;

	struct blkfront_info *info = rinfo->dev_info;

	unsigned long ring_size = info->nr_ring_pages * XEN_PAGE_SIZE;

	grant_ref_t gref[XENBUS_MAX_RING_GRANTS];



	for (i = 0; i < info->nr_ring_pages; i++)

		rinfo->ring_ref[i] = INVALID_GRANT_REF;



	sring = alloc_pages_exact(ring_size, GFP_NOIO);

	if (!sring) {

		xenbus_dev_fatal(dev, -ENOMEM, "allocating shared ring");

		return -ENOMEM;

	}

	SHARED_RING_INIT(sring);

	FRONT_RING_INIT(&rinfo->ring, sring, ring_size);



	err = xenbus_grant_ring(dev, rinfo->ring.sring, info->nr_ring_pages, gref);

	if (err < 0) {

		free_pages_exact(sring, ring_size);

		rinfo->ring.sring = NULL;

	err = xenbus_setup_ring(dev, GFP_NOIO, (void **)&sring,

				info->nr_ring_pages, rinfo->ring_ref);

	if (err)

		goto fail;

	}

	for (i = 0; i < info->nr_ring_pages; i++)

		rinfo->ring_ref[i] = gref[i];



	XEN_FRONT_RING_INIT(&rinfo->ring, sring, ring_size);



	err = xenbus_alloc_evtchn(dev, &rinfo->evtchn);

	if (err)