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authorTvrtko Ursulin <tvrtko.ursulin@intel.com>2022-10-03 17:04:02 +0100
committerTvrtko Ursulin <tvrtko.ursulin@intel.com>2022-10-03 17:04:02 +0100
commit97acb6a8fcc4e5c2cdc2693a35acdc5a7461aaa3 (patch)
treec4f1a18b38d655b7806a72515992bd9aae14ef53 /drivers/net/xen-netfront.c
parent6fa964c045a6bc3321a9186e87bfbcfd1059b0f1 (diff)
parent7860d720a84c74b2761c6b7995392a798ab0a3cb (diff)
Merge drm/drm-next into drm-intel-gt-next
Daniele needs 84d4333c1e28 ("misc/mei: Add NULL check to component match callback functions") in order to merge the DG2 HuC patches. Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Diffstat (limited to 'drivers/net/xen-netfront.c')
-rw-r--r--drivers/net/xen-netfront.c172
1 files changed, 92 insertions, 80 deletions
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index e2b4a1893a13..27a11cc08c61 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -66,6 +66,10 @@ module_param_named(max_queues, xennet_max_queues, uint, 0644);
MODULE_PARM_DESC(max_queues,
"Maximum number of queues per virtual interface");
+static bool __read_mostly xennet_trusted = true;
+module_param_named(trusted, xennet_trusted, bool, 0644);
+MODULE_PARM_DESC(trusted, "Is the backend trusted");
+
#define XENNET_TIMEOUT (5 * HZ)
static const struct ethtool_ops xennet_ethtool_ops;
@@ -78,8 +82,6 @@ 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)
@@ -175,6 +177,9 @@ struct netfront_info {
/* Is device behaving sane? */
bool broken;
+ /* Should skbs be bounced into a zeroed buffer? */
+ bool bounce;
+
atomic_t rx_gso_checksum_fixup;
};
@@ -224,7 +229,7 @@ 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;
}
@@ -273,7 +278,8 @@ static struct sk_buff *xennet_alloc_one_rx_buffer(struct netfront_queue *queue)
if (unlikely(!skb))
return NULL;
- page = page_pool_dev_alloc_pages(queue->page_pool);
+ page = page_pool_alloc_pages(queue->page_pool,
+ GFP_ATOMIC | __GFP_NOWARN | __GFP_ZERO);
if (unlikely(!page)) {
kfree_skb(skb);
return NULL;
@@ -432,7 +438,7 @@ 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);
@@ -667,6 +673,33 @@ static int xennet_xdp_xmit(struct net_device *dev, int n,
return nxmit;
}
+struct sk_buff *bounce_skb(const struct sk_buff *skb)
+{
+ unsigned int headerlen = skb_headroom(skb);
+ /* Align size to allocate full pages and avoid contiguous data leaks */
+ unsigned int size = ALIGN(skb_end_offset(skb) + skb->data_len,
+ XEN_PAGE_SIZE);
+ struct sk_buff *n = alloc_skb(size, GFP_ATOMIC | __GFP_ZERO);
+
+ if (!n)
+ return NULL;
+
+ if (!IS_ALIGNED((uintptr_t)n->head, XEN_PAGE_SIZE)) {
+ WARN_ONCE(1, "misaligned skb allocated\n");
+ kfree_skb(n);
+ return NULL;
+ }
+
+ /* Set the data pointer */
+ skb_reserve(n, headerlen);
+ /* Set the tail pointer and length */
+ skb_put(n, skb->len);
+
+ BUG_ON(skb_copy_bits(skb, -headerlen, n->head, headerlen + skb->len));
+
+ skb_copy_header(n, skb);
+ return n;
+}
#define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1)
@@ -720,9 +753,13 @@ static netdev_tx_t xennet_start_xmit(struct sk_buff *skb, struct net_device *dev
/* The first req should be at least ETH_HLEN size or the packet will be
* dropped by netback.
+ *
+ * If the backend is not trusted bounce all data to zeroed pages to
+ * avoid exposing contiguous data on the granted page not belonging to
+ * the skb.
*/
- if (unlikely(PAGE_SIZE - offset < ETH_HLEN)) {
- nskb = skb_copy(skb, GFP_ATOMIC);
+ if (np->bounce || unlikely(PAGE_SIZE - offset < ETH_HLEN)) {
+ nskb = bounce_skb(skb);
if (!nskb)
goto drop;
dev_consume_skb_any(skb);
@@ -868,7 +905,7 @@ static void xennet_set_rx_rsp_cons(struct netfront_queue *queue, RING_IDX val)
spin_lock_irqsave(&queue->rx_cons_lock, flags);
queue->rx.rsp_cons = val;
- queue->rx_rsp_unconsumed = RING_HAS_UNCONSUMED_RESPONSES(&queue->rx);
+ queue->rx_rsp_unconsumed = XEN_RING_NR_UNCONSUMED_RESPONSES(&queue->rx);
spin_unlock_irqrestore(&queue->rx_cons_lock, flags);
}
@@ -1006,22 +1043,12 @@ static int xennet_get_responses(struct netfront_queue *queue,
}
for (;;) {
- if (unlikely(rx->status < 0 ||
- rx->offset + rx->status > XEN_PAGE_SIZE)) {
- if (net_ratelimit())
- dev_warn(dev, "rx->offset: %u, size: %d\n",
- rx->offset, rx->status);
- xennet_move_rx_slot(queue, skb, ref);
- err = -EINVAL;
- goto next;
- }
-
/*
* This definitely indicates a bug, either in this driver or in
* 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);
@@ -1029,6 +1056,16 @@ static int xennet_get_responses(struct netfront_queue *queue,
goto next;
}
+ if (unlikely(rx->status < 0 ||
+ rx->offset + rx->status > XEN_PAGE_SIZE)) {
+ if (net_ratelimit())
+ dev_warn(dev, "rx->offset: %u, size: %d\n",
+ rx->offset, rx->status);
+ xennet_move_rx_slot(queue, skb, ref);
+ err = -EINVAL;
+ goto next;
+ }
+
if (!gnttab_end_foreign_access_ref(ref)) {
dev_alert(dev,
"Grant still in use by backend domain\n");
@@ -1055,8 +1092,10 @@ static int xennet_get_responses(struct netfront_queue *queue,
}
}
rcu_read_unlock();
-next:
+
__skb_queue_tail(list, skb);
+
+next:
if (!(rx->flags & XEN_NETRXF_more_data))
break;
@@ -1388,9 +1427,9 @@ static void xennet_release_tx_bufs(struct netfront_queue *queue)
queue->tx_skbs[i] = NULL;
get_page(queue->grant_tx_page[i]);
gnttab_end_foreign_access(queue->grant_tx_ref[i],
- (unsigned long)page_address(queue->grant_tx_page[i]));
+ 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 +1450,7 @@ 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]);
@@ -1420,9 +1459,8 @@ static void xennet_release_rx_bufs(struct netfront_queue *queue)
* foreign access is ended (which may be deferred).
*/
get_page(page);
- gnttab_end_foreign_access(ref,
- (unsigned long)page_address(page));
- queue->grant_rx_ref[id] = GRANT_INVALID_REF;
+ gnttab_end_foreign_access(ref, page);
+ queue->grant_rx_ref[id] = INVALID_GRANT_REF;
kfree_skb(skb);
}
@@ -1500,7 +1538,7 @@ static bool xennet_handle_rx(struct netfront_queue *queue, unsigned int *eoi)
return false;
spin_lock_irqsave(&queue->rx_cons_lock, flags);
- work_queued = RING_HAS_UNCONSUMED_RESPONSES(&queue->rx);
+ work_queued = XEN_RING_NR_UNCONSUMED_RESPONSES(&queue->rx);
if (work_queued > queue->rx_rsp_unconsumed) {
queue->rx_rsp_unconsumed = work_queued;
*eoi = 0;
@@ -1761,8 +1799,8 @@ 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)
- gnttab_end_foreign_access(ref, (unsigned long)page);
+ if (ref != INVALID_GRANT_REF)
+ gnttab_end_foreign_access(ref, virt_to_page(page));
}
static void xennet_disconnect_backend(struct netfront_info *info)
@@ -1798,8 +1836,8 @@ 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;
@@ -1923,42 +1961,27 @@ 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 = 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;
- 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)
- goto fail;
- queue->tx_ring_ref = gref;
+ XEN_FRONT_RING_INIT(&queue->tx, txs, XEN_PAGE_SIZE);
- 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");
+ err = xenbus_setup_ring(dev, GFP_NOIO | __GFP_HIGH, (void **)&rxs,
+ 1, &queue->rx_ring_ref);
+ if (err)
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;
+ XEN_FRONT_RING_INIT(&queue->rx, rxs, XEN_PAGE_SIZE);
if (feature_split_evtchn)
err = setup_netfront_split(queue);
@@ -1974,24 +1997,10 @@ 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 != GRANT_INVALID_REF) {
- gnttab_end_foreign_access(queue->rx_ring_ref,
- (unsigned long)rxs);
- queue->rx_ring_ref = GRANT_INVALID_REF;
- } else {
- free_page((unsigned long)rxs);
- }
- if (queue->tx_ring_ref != GRANT_INVALID_REF) {
- gnttab_end_foreign_access(queue->tx_ring_ref,
- (unsigned long)txs);
- queue->tx_ring_ref = GRANT_INVALID_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;
}
@@ -2020,7 +2029,7 @@ 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 +2037,7 @@ 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 */
@@ -2246,6 +2255,10 @@ static int talk_to_netback(struct xenbus_device *dev,
info->netdev->irq = 0;
+ /* Check if backend is trusted. */
+ info->bounce = !xennet_trusted ||
+ !xenbus_read_unsigned(dev->nodename, "trusted", 1);
+
/* Check if backend supports multiple queues */
max_queues = xenbus_read_unsigned(info->xbdev->otherend,
"multi-queue-max-queues", 1);
@@ -2413,6 +2426,9 @@ static int xennet_connect(struct net_device *dev)
return err;
if (np->netback_has_xdp_headroom)
pr_info("backend supports XDP headroom\n");
+ if (np->bounce)
+ dev_info(&np->xbdev->dev,
+ "bouncing transmitted data to zeroed pages\n");
/* talk_to_netback() sets the correct number of queues */
num_queues = dev->real_num_tx_queues;
@@ -2448,10 +2464,6 @@ static int xennet_connect(struct net_device *dev)
if (queue->tx_irq != queue->rx_irq)
notify_remote_via_irq(queue->rx_irq);
- spin_lock_irq(&queue->tx_lock);
- xennet_tx_buf_gc(queue);
- spin_unlock_irq(&queue->tx_lock);
-
spin_lock_bh(&queue->rx_lock);
xennet_alloc_rx_buffers(queue);
spin_unlock_bh(&queue->rx_lock);