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path: root/drivers/net/xen-netback
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Diffstat (limited to 'drivers/net/xen-netback')
-rw-r--r--drivers/net/xen-netback/netback.c223
1 files changed, 123 insertions, 100 deletions
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 3d2081bbbc86..054ac0e897f6 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -332,10 +332,13 @@ static int xenvif_count_requests(struct xenvif_queue *queue,
struct xenvif_tx_cb {
- u16 pending_idx;
+ u16 copy_pending_idx[XEN_NETBK_LEGACY_SLOTS_MAX + 1];
+ u8 copy_count;
};
#define XENVIF_TX_CB(skb) ((struct xenvif_tx_cb *)(skb)->cb)
+#define copy_pending_idx(skb, i) (XENVIF_TX_CB(skb)->copy_pending_idx[i])
+#define copy_count(skb) (XENVIF_TX_CB(skb)->copy_count)
static inline void xenvif_tx_create_map_op(struct xenvif_queue *queue,
u16 pending_idx,
@@ -370,31 +373,93 @@ static inline struct sk_buff *xenvif_alloc_skb(unsigned int size)
return skb;
}
-static struct gnttab_map_grant_ref *xenvif_get_requests(struct xenvif_queue *queue,
- struct sk_buff *skb,
- struct xen_netif_tx_request *txp,
- struct gnttab_map_grant_ref *gop,
- unsigned int frag_overflow,
- struct sk_buff *nskb)
+static void xenvif_get_requests(struct xenvif_queue *queue,
+ struct sk_buff *skb,
+ struct xen_netif_tx_request *first,
+ struct xen_netif_tx_request *txfrags,
+ unsigned *copy_ops,
+ unsigned *map_ops,
+ unsigned int frag_overflow,
+ struct sk_buff *nskb,
+ unsigned int extra_count,
+ unsigned int data_len)
{
struct skb_shared_info *shinfo = skb_shinfo(skb);
skb_frag_t *frags = shinfo->frags;
- u16 pending_idx = XENVIF_TX_CB(skb)->pending_idx;
- int start;
+ u16 pending_idx;
pending_ring_idx_t index;
unsigned int nr_slots;
+ struct gnttab_copy *cop = queue->tx_copy_ops + *copy_ops;
+ struct gnttab_map_grant_ref *gop = queue->tx_map_ops + *map_ops;
+ struct xen_netif_tx_request *txp = first;
+
+ nr_slots = shinfo->nr_frags + 1;
+
+ copy_count(skb) = 0;
+
+ /* Create copy ops for exactly data_len bytes into the skb head. */
+ __skb_put(skb, data_len);
+ while (data_len > 0) {
+ int amount = data_len > txp->size ? txp->size : data_len;
+
+ cop->source.u.ref = txp->gref;
+ cop->source.domid = queue->vif->domid;
+ cop->source.offset = txp->offset;
+
+ cop->dest.domid = DOMID_SELF;
+ cop->dest.offset = (offset_in_page(skb->data +
+ skb_headlen(skb) -
+ data_len)) & ~XEN_PAGE_MASK;
+ cop->dest.u.gmfn = virt_to_gfn(skb->data + skb_headlen(skb)
+ - data_len);
+
+ cop->len = amount;
+ cop->flags = GNTCOPY_source_gref;
- nr_slots = shinfo->nr_frags;
+ index = pending_index(queue->pending_cons);
+ pending_idx = queue->pending_ring[index];
+ callback_param(queue, pending_idx).ctx = NULL;
+ copy_pending_idx(skb, copy_count(skb)) = pending_idx;
+ copy_count(skb)++;
+
+ cop++;
+ data_len -= amount;
- /* Skip first skb fragment if it is on same page as header fragment. */
- start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
+ if (amount == txp->size) {
+ /* The copy op covered the full tx_request */
+
+ memcpy(&queue->pending_tx_info[pending_idx].req,
+ txp, sizeof(*txp));
+ queue->pending_tx_info[pending_idx].extra_count =
+ (txp == first) ? extra_count : 0;
+
+ if (txp == first)
+ txp = txfrags;
+ else
+ txp++;
+ queue->pending_cons++;
+ nr_slots--;
+ } else {
+ /* The copy op partially covered the tx_request.
+ * The remainder will be mapped.
+ */
+ txp->offset += amount;
+ txp->size -= amount;
+ }
+ }
- for (shinfo->nr_frags = start; shinfo->nr_frags < nr_slots;
- shinfo->nr_frags++, txp++, gop++) {
+ for (shinfo->nr_frags = 0; shinfo->nr_frags < nr_slots;
+ shinfo->nr_frags++, gop++) {
index = pending_index(queue->pending_cons++);
pending_idx = queue->pending_ring[index];
- xenvif_tx_create_map_op(queue, pending_idx, txp, 0, gop);
+ xenvif_tx_create_map_op(queue, pending_idx, txp,
+ txp == first ? extra_count : 0, gop);
frag_set_pending_idx(&frags[shinfo->nr_frags], pending_idx);
+
+ if (txp == first)
+ txp = txfrags;
+ else
+ txp++;
}
if (frag_overflow) {
@@ -415,7 +480,8 @@ static struct gnttab_map_grant_ref *xenvif_get_requests(struct xenvif_queue *que
skb_shinfo(skb)->frag_list = nskb;
}
- return gop;
+ (*copy_ops) = cop - queue->tx_copy_ops;
+ (*map_ops) = gop - queue->tx_map_ops;
}
static inline void xenvif_grant_handle_set(struct xenvif_queue *queue,
@@ -451,7 +517,7 @@ static int xenvif_tx_check_gop(struct xenvif_queue *queue,
struct gnttab_copy **gopp_copy)
{
struct gnttab_map_grant_ref *gop_map = *gopp_map;
- u16 pending_idx = XENVIF_TX_CB(skb)->pending_idx;
+ u16 pending_idx;
/* This always points to the shinfo of the skb being checked, which
* could be either the first or the one on the frag_list
*/
@@ -462,24 +528,37 @@ static int xenvif_tx_check_gop(struct xenvif_queue *queue,
struct skb_shared_info *first_shinfo = NULL;
int nr_frags = shinfo->nr_frags;
const bool sharedslot = nr_frags &&
- frag_get_pending_idx(&shinfo->frags[0]) == pending_idx;
+ frag_get_pending_idx(&shinfo->frags[0]) ==
+ copy_pending_idx(skb, copy_count(skb) - 1);
int i, err;
- /* Check status of header. */
- err = (*gopp_copy)->status;
- if (unlikely(err)) {
- if (net_ratelimit())
- netdev_dbg(queue->vif->dev,
- "Grant copy of header failed! status: %d pending_idx: %u ref: %u\n",
- (*gopp_copy)->status,
- pending_idx,
- (*gopp_copy)->source.u.ref);
- /* The first frag might still have this slot mapped */
- if (!sharedslot)
- xenvif_idx_release(queue, pending_idx,
- XEN_NETIF_RSP_ERROR);
+ for (i = 0; i < copy_count(skb); i++) {
+ int newerr;
+
+ /* Check status of header. */
+ pending_idx = copy_pending_idx(skb, i);
+
+ newerr = (*gopp_copy)->status;
+ if (likely(!newerr)) {
+ /* The first frag might still have this slot mapped */
+ if (i < copy_count(skb) - 1 || !sharedslot)
+ xenvif_idx_release(queue, pending_idx,
+ XEN_NETIF_RSP_OKAY);
+ } else {
+ err = newerr;
+ if (net_ratelimit())
+ netdev_dbg(queue->vif->dev,
+ "Grant copy of header failed! status: %d pending_idx: %u ref: %u\n",
+ (*gopp_copy)->status,
+ pending_idx,
+ (*gopp_copy)->source.u.ref);
+ /* The first frag might still have this slot mapped */
+ if (i < copy_count(skb) - 1 || !sharedslot)
+ xenvif_idx_release(queue, pending_idx,
+ XEN_NETIF_RSP_ERROR);
+ }
+ (*gopp_copy)++;
}
- (*gopp_copy)++;
check_frags:
for (i = 0; i < nr_frags; i++, gop_map++) {
@@ -526,14 +605,6 @@ check_frags:
if (err)
continue;
- /* First error: if the header haven't shared a slot with the
- * first frag, release it as well.
- */
- if (!sharedslot)
- xenvif_idx_release(queue,
- XENVIF_TX_CB(skb)->pending_idx,
- XEN_NETIF_RSP_OKAY);
-
/* Invalidate preceding fragments of this skb. */
for (j = 0; j < i; j++) {
pending_idx = frag_get_pending_idx(&shinfo->frags[j]);
@@ -803,7 +874,6 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
unsigned *copy_ops,
unsigned *map_ops)
{
- struct gnttab_map_grant_ref *gop = queue->tx_map_ops;
struct sk_buff *skb, *nskb;
int ret;
unsigned int frag_overflow;
@@ -885,8 +955,12 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
continue;
}
+ data_len = (txreq.size > XEN_NETBACK_TX_COPY_LEN) ?
+ XEN_NETBACK_TX_COPY_LEN : txreq.size;
+
ret = xenvif_count_requests(queue, &txreq, extra_count,
txfrags, work_to_do);
+
if (unlikely(ret < 0))
break;
@@ -912,9 +986,8 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
index = pending_index(queue->pending_cons);
pending_idx = queue->pending_ring[index];
- data_len = (txreq.size > XEN_NETBACK_TX_COPY_LEN &&
- ret < XEN_NETBK_LEGACY_SLOTS_MAX) ?
- XEN_NETBACK_TX_COPY_LEN : txreq.size;
+ if (ret >= XEN_NETBK_LEGACY_SLOTS_MAX - 1 && data_len < txreq.size)
+ data_len = txreq.size;
skb = xenvif_alloc_skb(data_len);
if (unlikely(skb == NULL)) {
@@ -925,8 +998,6 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
}
skb_shinfo(skb)->nr_frags = ret;
- if (data_len < txreq.size)
- skb_shinfo(skb)->nr_frags++;
/* At this point shinfo->nr_frags is in fact the number of
* slots, which can be as large as XEN_NETBK_LEGACY_SLOTS_MAX.
*/
@@ -988,54 +1059,19 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
type);
}
- XENVIF_TX_CB(skb)->pending_idx = pending_idx;
-
- __skb_put(skb, data_len);
- queue->tx_copy_ops[*copy_ops].source.u.ref = txreq.gref;
- queue->tx_copy_ops[*copy_ops].source.domid = queue->vif->domid;
- queue->tx_copy_ops[*copy_ops].source.offset = txreq.offset;
-
- queue->tx_copy_ops[*copy_ops].dest.u.gmfn =
- virt_to_gfn(skb->data);
- queue->tx_copy_ops[*copy_ops].dest.domid = DOMID_SELF;
- queue->tx_copy_ops[*copy_ops].dest.offset =
- offset_in_page(skb->data) & ~XEN_PAGE_MASK;
-
- queue->tx_copy_ops[*copy_ops].len = data_len;
- queue->tx_copy_ops[*copy_ops].flags = GNTCOPY_source_gref;
-
- (*copy_ops)++;
-
- if (data_len < txreq.size) {
- frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
- pending_idx);
- xenvif_tx_create_map_op(queue, pending_idx, &txreq,
- extra_count, gop);
- gop++;
- } else {
- frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
- INVALID_PENDING_IDX);
- memcpy(&queue->pending_tx_info[pending_idx].req,
- &txreq, sizeof(txreq));
- queue->pending_tx_info[pending_idx].extra_count =
- extra_count;
- }
-
- queue->pending_cons++;
-
- gop = xenvif_get_requests(queue, skb, txfrags, gop,
- frag_overflow, nskb);
+ xenvif_get_requests(queue, skb, &txreq, txfrags, copy_ops,
+ map_ops, frag_overflow, nskb, extra_count,
+ data_len);
__skb_queue_tail(&queue->tx_queue, skb);
queue->tx.req_cons = idx;
- if (((gop-queue->tx_map_ops) >= ARRAY_SIZE(queue->tx_map_ops)) ||
+ if ((*map_ops >= ARRAY_SIZE(queue->tx_map_ops)) ||
(*copy_ops >= ARRAY_SIZE(queue->tx_copy_ops)))
break;
}
- (*map_ops) = gop - queue->tx_map_ops;
return;
}
@@ -1114,9 +1150,8 @@ static int xenvif_tx_submit(struct xenvif_queue *queue)
while ((skb = __skb_dequeue(&queue->tx_queue)) != NULL) {
struct xen_netif_tx_request *txp;
u16 pending_idx;
- unsigned data_len;
- pending_idx = XENVIF_TX_CB(skb)->pending_idx;
+ pending_idx = copy_pending_idx(skb, 0);
txp = &queue->pending_tx_info[pending_idx].req;
/* Check the remap error code. */
@@ -1135,18 +1170,6 @@ static int xenvif_tx_submit(struct xenvif_queue *queue)
continue;
}
- data_len = skb->len;
- callback_param(queue, pending_idx).ctx = NULL;
- if (data_len < txp->size) {
- /* Append the packet payload as a fragment. */
- txp->offset += data_len;
- txp->size -= data_len;
- } else {
- /* Schedule a response immediately. */
- xenvif_idx_release(queue, pending_idx,
- XEN_NETIF_RSP_OKAY);
- }
-
if (txp->flags & XEN_NETTXF_csum_blank)
skb->ip_summed = CHECKSUM_PARTIAL;
else if (txp->flags & XEN_NETTXF_data_validated)
@@ -1332,7 +1355,7 @@ static inline void xenvif_tx_dealloc_action(struct xenvif_queue *queue)
/* Called after netfront has transmitted */
int xenvif_tx_action(struct xenvif_queue *queue, int budget)
{
- unsigned nr_mops, nr_cops = 0;
+ unsigned nr_mops = 0, nr_cops = 0;
int work_done, ret;
if (unlikely(!tx_work_todo(queue)))