* [PATCH 02/18] xen/netfront: switch netfront to use INVALID_GRANT_REF
2022-04-20 15:09 [PATCH 00/18] xen: simplify frontend side ring setup Juergen Gross
@ 2022-04-20 15:09 ` Juergen Gross
2022-04-20 15:09 ` [PATCH 11/18] xen/netfront: use xenbus_setup_ring() and xenbus_teardown_ring() Juergen Gross
1 sibling, 0 replies; 3+ messages in thread
From: Juergen Gross @ 2022-04-20 15:09 UTC (permalink / raw)
To: xen-devel, netdev, linux-kernel
Cc: Juergen Gross, Boris Ostrovsky, Stefano Stabellini,
David S. Miller, Jakub Kicinski, Paolo Abeni
Instead of using a private macro for an invalid grant reference use
the common one.
Signed-off-by: Juergen Gross <jgross@suse.com>
---
drivers/net/xen-netfront.c | 36 +++++++++++++++++-------------------
1 file changed, 17 insertions(+), 19 deletions(-)
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index e2b4a1893a13..af3d3de7d9fa 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -78,8 +78,6 @@ struct netfront_cb {
#define RX_COPY_THRESHOLD 256
-#define GRANT_INVALID_REF 0
-
#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, XEN_PAGE_SIZE)
#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, XEN_PAGE_SIZE)
@@ -224,7 +222,7 @@ static grant_ref_t xennet_get_rx_ref(struct netfront_queue *queue,
{
int i = xennet_rxidx(ri);
grant_ref_t ref = queue->grant_rx_ref[i];
- queue->grant_rx_ref[i] = GRANT_INVALID_REF;
+ queue->grant_rx_ref[i] = INVALID_GRANT_REF;
return ref;
}
@@ -432,7 +430,7 @@ static bool xennet_tx_buf_gc(struct netfront_queue *queue)
}
gnttab_release_grant_reference(
&queue->gref_tx_head, queue->grant_tx_ref[id]);
- queue->grant_tx_ref[id] = GRANT_INVALID_REF;
+ queue->grant_tx_ref[id] = INVALID_GRANT_REF;
queue->grant_tx_page[id] = NULL;
add_id_to_list(&queue->tx_skb_freelist, queue->tx_link, id);
dev_kfree_skb_irq(skb);
@@ -1021,7 +1019,7 @@ static int xennet_get_responses(struct netfront_queue *queue,
* the backend driver. In future this should flag the bad
* situation to the system controller to reboot the backend.
*/
- if (ref == GRANT_INVALID_REF) {
+ if (ref == INVALID_GRANT_REF) {
if (net_ratelimit())
dev_warn(dev, "Bad rx response id %d.\n",
rx->id);
@@ -1390,7 +1388,7 @@ static void xennet_release_tx_bufs(struct netfront_queue *queue)
gnttab_end_foreign_access(queue->grant_tx_ref[i],
(unsigned long)page_address(queue->grant_tx_page[i]));
queue->grant_tx_page[i] = NULL;
- queue->grant_tx_ref[i] = GRANT_INVALID_REF;
+ queue->grant_tx_ref[i] = INVALID_GRANT_REF;
add_id_to_list(&queue->tx_skb_freelist, queue->tx_link, i);
dev_kfree_skb_irq(skb);
}
@@ -1411,7 +1409,7 @@ static void xennet_release_rx_bufs(struct netfront_queue *queue)
continue;
ref = queue->grant_rx_ref[id];
- if (ref == GRANT_INVALID_REF)
+ if (ref == INVALID_GRANT_REF)
continue;
page = skb_frag_page(&skb_shinfo(skb)->frags[0]);
@@ -1422,7 +1420,7 @@ static void xennet_release_rx_bufs(struct netfront_queue *queue)
get_page(page);
gnttab_end_foreign_access(ref,
(unsigned long)page_address(page));
- queue->grant_rx_ref[id] = GRANT_INVALID_REF;
+ queue->grant_rx_ref[id] = INVALID_GRANT_REF;
kfree_skb(skb);
}
@@ -1761,7 +1759,7 @@ static int netfront_probe(struct xenbus_device *dev,
static void xennet_end_access(int ref, void *page)
{
/* This frees the page as a side-effect */
- if (ref != GRANT_INVALID_REF)
+ if (ref != INVALID_GRANT_REF)
gnttab_end_foreign_access(ref, (unsigned long)page);
}
@@ -1798,8 +1796,8 @@ static void xennet_disconnect_backend(struct netfront_info *info)
xennet_end_access(queue->tx_ring_ref, queue->tx.sring);
xennet_end_access(queue->rx_ring_ref, queue->rx.sring);
- queue->tx_ring_ref = GRANT_INVALID_REF;
- queue->rx_ring_ref = GRANT_INVALID_REF;
+ queue->tx_ring_ref = INVALID_GRANT_REF;
+ queue->rx_ring_ref = INVALID_GRANT_REF;
queue->tx.sring = NULL;
queue->rx.sring = NULL;
@@ -1927,8 +1925,8 @@ static int setup_netfront(struct xenbus_device *dev,
grant_ref_t gref;
int err;
- queue->tx_ring_ref = GRANT_INVALID_REF;
- queue->rx_ring_ref = GRANT_INVALID_REF;
+ queue->tx_ring_ref = INVALID_GRANT_REF;
+ queue->rx_ring_ref = INVALID_GRANT_REF;
queue->rx.sring = NULL;
queue->tx.sring = NULL;
@@ -1978,17 +1976,17 @@ static int setup_netfront(struct xenbus_device *dev,
* granted pages because backend is not accessing it at this point.
*/
fail:
- if (queue->rx_ring_ref != GRANT_INVALID_REF) {
+ if (queue->rx_ring_ref != INVALID_GRANT_REF) {
gnttab_end_foreign_access(queue->rx_ring_ref,
(unsigned long)rxs);
- queue->rx_ring_ref = GRANT_INVALID_REF;
+ queue->rx_ring_ref = INVALID_GRANT_REF;
} else {
free_page((unsigned long)rxs);
}
- if (queue->tx_ring_ref != GRANT_INVALID_REF) {
+ if (queue->tx_ring_ref != INVALID_GRANT_REF) {
gnttab_end_foreign_access(queue->tx_ring_ref,
(unsigned long)txs);
- queue->tx_ring_ref = GRANT_INVALID_REF;
+ queue->tx_ring_ref = INVALID_GRANT_REF;
} else {
free_page((unsigned long)txs);
}
@@ -2020,7 +2018,7 @@ static int xennet_init_queue(struct netfront_queue *queue)
queue->tx_pend_queue = TX_LINK_NONE;
for (i = 0; i < NET_TX_RING_SIZE; i++) {
queue->tx_link[i] = i + 1;
- queue->grant_tx_ref[i] = GRANT_INVALID_REF;
+ queue->grant_tx_ref[i] = INVALID_GRANT_REF;
queue->grant_tx_page[i] = NULL;
}
queue->tx_link[NET_TX_RING_SIZE - 1] = TX_LINK_NONE;
@@ -2028,7 +2026,7 @@ static int xennet_init_queue(struct netfront_queue *queue)
/* Clear out rx_skbs */
for (i = 0; i < NET_RX_RING_SIZE; i++) {
queue->rx_skbs[i] = NULL;
- queue->grant_rx_ref[i] = GRANT_INVALID_REF;
+ queue->grant_rx_ref[i] = INVALID_GRANT_REF;
}
/* A grant for every tx ring slot */
--
2.34.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* [PATCH 11/18] xen/netfront: use xenbus_setup_ring() and xenbus_teardown_ring()
2022-04-20 15:09 [PATCH 00/18] xen: simplify frontend side ring setup Juergen Gross
2022-04-20 15:09 ` [PATCH 02/18] xen/netfront: switch netfront to use INVALID_GRANT_REF Juergen Gross
@ 2022-04-20 15:09 ` Juergen Gross
1 sibling, 0 replies; 3+ messages in thread
From: Juergen Gross @ 2022-04-20 15:09 UTC (permalink / raw)
To: xen-devel, netdev, linux-kernel
Cc: Juergen Gross, Boris Ostrovsky, Stefano Stabellini,
David S. Miller, Jakub Kicinski, Paolo Abeni
Simplify netfront's ring creation and removal via xenbus_setup_ring()
and xenbus_teardown_ring().
Signed-off-by: Juergen Gross <jgross@suse.com>
---
drivers/net/xen-netfront.c | 49 +++++++++-----------------------------
1 file changed, 11 insertions(+), 38 deletions(-)
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index af3d3de7d9fa..880b10d435d9 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1921,8 +1921,7 @@ static int setup_netfront(struct xenbus_device *dev,
struct netfront_queue *queue, unsigned int feature_split_evtchn)
{
struct xen_netif_tx_sring *txs;
- struct xen_netif_rx_sring *rxs = NULL;
- grant_ref_t gref;
+ struct xen_netif_rx_sring *rxs;
int err;
queue->tx_ring_ref = INVALID_GRANT_REF;
@@ -1930,34 +1929,22 @@ static int setup_netfront(struct xenbus_device *dev,
queue->rx.sring = NULL;
queue->tx.sring = NULL;
- txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
- if (!txs) {
- err = -ENOMEM;
- xenbus_dev_fatal(dev, err, "allocating tx ring page");
+ err = xenbus_setup_ring(dev, GFP_NOIO | __GFP_HIGH, (void **)&txs,
+ 1, &queue->tx_ring_ref);
+ if (err)
goto fail;
- }
+
SHARED_RING_INIT(txs);
FRONT_RING_INIT(&queue->tx, txs, XEN_PAGE_SIZE);
- err = xenbus_grant_ring(dev, txs, 1, &gref);
- if (err < 0)
+ err = xenbus_setup_ring(dev, GFP_NOIO | __GFP_HIGH, (void **)&rxs,
+ 1, &queue->rx_ring_ref);
+ if (err)
goto fail;
- queue->tx_ring_ref = gref;
- rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
- if (!rxs) {
- err = -ENOMEM;
- xenbus_dev_fatal(dev, err, "allocating rx ring page");
- goto fail;
- }
SHARED_RING_INIT(rxs);
FRONT_RING_INIT(&queue->rx, rxs, XEN_PAGE_SIZE);
- err = xenbus_grant_ring(dev, rxs, 1, &gref);
- if (err < 0)
- goto fail;
- queue->rx_ring_ref = gref;
-
if (feature_split_evtchn)
err = setup_netfront_split(queue);
/* setup single event channel if
@@ -1972,24 +1959,10 @@ static int setup_netfront(struct xenbus_device *dev,
return 0;
- /* If we fail to setup netfront, it is safe to just revoke access to
- * granted pages because backend is not accessing it at this point.
- */
fail:
- if (queue->rx_ring_ref != INVALID_GRANT_REF) {
- gnttab_end_foreign_access(queue->rx_ring_ref,
- (unsigned long)rxs);
- queue->rx_ring_ref = INVALID_GRANT_REF;
- } else {
- free_page((unsigned long)rxs);
- }
- if (queue->tx_ring_ref != INVALID_GRANT_REF) {
- gnttab_end_foreign_access(queue->tx_ring_ref,
- (unsigned long)txs);
- queue->tx_ring_ref = INVALID_GRANT_REF;
- } else {
- free_page((unsigned long)txs);
- }
+ xenbus_teardown_ring((void **)&queue->rx.sring, 1, &queue->rx_ring_ref);
+ xenbus_teardown_ring((void **)&queue->tx.sring, 1, &queue->tx_ring_ref);
+
return err;
}
--
2.34.1
^ permalink raw reply related [flat|nested] 3+ messages in thread