From ca2f09f2b2c6c25047cfc545d057c4edfcfe561c Mon Sep 17 00:00:00 2001 From: Paul Durrant Date: Fri, 6 Dec 2013 16:36:07 +0000 Subject: xen-netback: improve guest-receive-side flow control The way that flow control works without this patch is that, in start_xmit() the code uses xenvif_count_skb_slots() to predict how many slots xenvif_gop_skb() will consume and then adds this to a 'req_cons_peek' counter which it then uses to determine if the shared ring has that amount of space available by checking whether 'req_prod' has passed that value. If the ring doesn't have space the tx queue is stopped. xenvif_gop_skb() will then consume slots and update 'req_cons' and issue responses, updating 'rsp_prod' as it goes. The frontend will consume those responses and post new requests, by updating req_prod. So, req_prod chases req_cons which chases rsp_prod, and can never exceed that value. Thus if xenvif_count_skb_slots() ever returns a number of slots greater than xenvif_gop_skb() uses, req_cons_peek will get to a value that req_prod cannot possibly achieve (since it's limited by the 'real' req_cons) and, if this happens enough times, req_cons_peek gets more than a ring size ahead of req_cons and the tx queue then remains stopped forever waiting for an unachievable amount of space to become available in the ring. Having two routines trying to calculate the same value is always going to be fragile, so this patch does away with that. All we essentially need to do is make sure that we have 'enough stuff' on our internal queue without letting it build up uncontrollably. So start_xmit() makes a cheap optimistic check of how much space is needed for an skb and only turns the queue off if that is unachievable. net_rx_action() is the place where we could do with an accurate predicition but, since that has proven tricky to calculate, a cheap worse-case (but not too bad) estimate is all we really need since the only thing we *must* prevent is xenvif_gop_skb() consuming more slots than are available. Without this patch I can trivially stall netback permanently by just doing a large guest to guest file copy between two Windows Server 2008R2 VMs on a single host. Patch tested with frontends in: - Windows Server 2008R2 - CentOS 6.0 - Debian Squeeze - Debian Wheezy - SLES11 Signed-off-by: Paul Durrant Cc: Wei Liu Cc: Ian Campbell Cc: David Vrabel Cc: Annie Li Cc: Konrad Rzeszutek Wilk Acked-by: Wei Liu Signed-off-by: David S. Miller --- drivers/net/xen-netback/netback.c | 217 +++++++++++++------------------------- 1 file changed, 71 insertions(+), 146 deletions(-) (limited to 'drivers/net/xen-netback/netback.c') diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index acf13920e6d..43341b82649 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -138,36 +138,26 @@ static inline pending_ring_idx_t nr_pending_reqs(struct xenvif *vif) vif->pending_prod + vif->pending_cons; } -static int max_required_rx_slots(struct xenvif *vif) +bool xenvif_rx_ring_slots_available(struct xenvif *vif, int needed) { - int max = DIV_ROUND_UP(vif->dev->mtu, PAGE_SIZE); + RING_IDX prod, cons; - /* XXX FIXME: RX path dependent on MAX_SKB_FRAGS */ - if (vif->can_sg || vif->gso_mask || vif->gso_prefix_mask) - max += MAX_SKB_FRAGS + 1; /* extra_info + frags */ - - return max; -} - -int xenvif_rx_ring_full(struct xenvif *vif) -{ - RING_IDX peek = vif->rx_req_cons_peek; - RING_IDX needed = max_required_rx_slots(vif); + do { + prod = vif->rx.sring->req_prod; + cons = vif->rx.req_cons; - return ((vif->rx.sring->req_prod - peek) < needed) || - ((vif->rx.rsp_prod_pvt + XEN_NETIF_RX_RING_SIZE - peek) < needed); -} + if (prod - cons >= needed) + return true; -int xenvif_must_stop_queue(struct xenvif *vif) -{ - if (!xenvif_rx_ring_full(vif)) - return 0; + vif->rx.sring->req_event = prod + 1; - vif->rx.sring->req_event = vif->rx_req_cons_peek + - max_required_rx_slots(vif); - mb(); /* request notification /then/ check the queue */ + /* Make sure event is visible before we check prod + * again. + */ + mb(); + } while (vif->rx.sring->req_prod != prod); - return xenvif_rx_ring_full(vif); + return false; } /* @@ -210,93 +200,6 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head) return false; } -struct xenvif_count_slot_state { - unsigned long copy_off; - bool head; -}; - -unsigned int xenvif_count_frag_slots(struct xenvif *vif, - unsigned long offset, unsigned long size, - struct xenvif_count_slot_state *state) -{ - unsigned count = 0; - - offset &= ~PAGE_MASK; - - while (size > 0) { - unsigned long bytes; - - bytes = PAGE_SIZE - offset; - - if (bytes > size) - bytes = size; - - if (start_new_rx_buffer(state->copy_off, bytes, state->head)) { - count++; - state->copy_off = 0; - } - - if (state->copy_off + bytes > MAX_BUFFER_OFFSET) - bytes = MAX_BUFFER_OFFSET - state->copy_off; - - state->copy_off += bytes; - - offset += bytes; - size -= bytes; - - if (offset == PAGE_SIZE) - offset = 0; - - state->head = false; - } - - return count; -} - -/* - * Figure out how many ring slots we're going to need to send @skb to - * the guest. This function is essentially a dry run of - * xenvif_gop_frag_copy. - */ -unsigned int xenvif_count_skb_slots(struct xenvif *vif, struct sk_buff *skb) -{ - struct xenvif_count_slot_state state; - unsigned int count; - unsigned char *data; - unsigned i; - - state.head = true; - state.copy_off = 0; - - /* Slot for the first (partial) page of data. */ - count = 1; - - /* Need a slot for the GSO prefix for GSO extra data? */ - if (skb_shinfo(skb)->gso_size) - count++; - - data = skb->data; - while (data < skb_tail_pointer(skb)) { - unsigned long offset = offset_in_page(data); - unsigned long size = PAGE_SIZE - offset; - - if (data + size > skb_tail_pointer(skb)) - size = skb_tail_pointer(skb) - data; - - count += xenvif_count_frag_slots(vif, offset, size, &state); - - data += size; - } - - for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]); - unsigned long offset = skb_shinfo(skb)->frags[i].page_offset; - - count += xenvif_count_frag_slots(vif, offset, size, &state); - } - return count; -} - struct netrx_pending_operations { unsigned copy_prod, copy_cons; unsigned meta_prod, meta_cons; @@ -557,12 +460,12 @@ struct skb_cb_overlay { int meta_slots_used; }; -static void xenvif_kick_thread(struct xenvif *vif) +void xenvif_kick_thread(struct xenvif *vif) { wake_up(&vif->wq); } -void xenvif_rx_action(struct xenvif *vif) +static void xenvif_rx_action(struct xenvif *vif) { s8 status; u16 flags; @@ -571,8 +474,6 @@ void xenvif_rx_action(struct xenvif *vif) struct sk_buff *skb; LIST_HEAD(notify); int ret; - int nr_frags; - int count; unsigned long offset; struct skb_cb_overlay *sco; int need_to_notify = 0; @@ -584,29 +485,44 @@ void xenvif_rx_action(struct xenvif *vif) skb_queue_head_init(&rxq); - count = 0; - while ((skb = skb_dequeue(&vif->rx_queue)) != NULL) { - vif = netdev_priv(skb->dev); - nr_frags = skb_shinfo(skb)->nr_frags; + int max_slots_needed; + int i; + + /* We need a cheap worse case estimate for the number of + * slots we'll use. + */ + + max_slots_needed = DIV_ROUND_UP(offset_in_page(skb->data) + + skb_headlen(skb), + PAGE_SIZE); + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + unsigned int size; + size = skb_frag_size(&skb_shinfo(skb)->frags[i]); + max_slots_needed += DIV_ROUND_UP(size, PAGE_SIZE); + } + if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 || + skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) + max_slots_needed++; + + /* If the skb may not fit then bail out now */ + if (!xenvif_rx_ring_slots_available(vif, max_slots_needed)) { + skb_queue_head(&vif->rx_queue, skb); + need_to_notify = 1; + break; + } sco = (struct skb_cb_overlay *)skb->cb; sco->meta_slots_used = xenvif_gop_skb(skb, &npo); - - count += nr_frags + 1; + BUG_ON(sco->meta_slots_used > max_slots_needed); __skb_queue_tail(&rxq, skb); - - /* Filled the batch queue? */ - /* XXX FIXME: RX path dependent on MAX_SKB_FRAGS */ - if (count + MAX_SKB_FRAGS >= XEN_NETIF_RX_RING_SIZE) - break; } BUG_ON(npo.meta_prod > ARRAY_SIZE(vif->meta)); if (!npo.copy_prod) - return; + goto done; BUG_ON(npo.copy_prod > ARRAY_SIZE(vif->grant_copy_op)); gnttab_batch_copy(vif->grant_copy_op, npo.copy_prod); @@ -614,8 +530,6 @@ void xenvif_rx_action(struct xenvif *vif) while ((skb = __skb_dequeue(&rxq)) != NULL) { sco = (struct skb_cb_overlay *)skb->cb; - vif = netdev_priv(skb->dev); - if ((1 << vif->meta[npo.meta_cons].gso_type) & vif->gso_prefix_mask) { resp = RING_GET_RESPONSE(&vif->rx, @@ -681,25 +595,13 @@ void xenvif_rx_action(struct xenvif *vif) if (ret) need_to_notify = 1; - xenvif_notify_tx_completion(vif); - npo.meta_cons += sco->meta_slots_used; dev_kfree_skb(skb); } +done: if (need_to_notify) notify_remote_via_irq(vif->rx_irq); - - /* More work to do? */ - if (!skb_queue_empty(&vif->rx_queue)) - xenvif_kick_thread(vif); -} - -void xenvif_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb) -{ - skb_queue_tail(&vif->rx_queue, skb); - - xenvif_kick_thread(vif); } void xenvif_check_rx_xenvif(struct xenvif *vif) @@ -1804,7 +1706,7 @@ static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif, static inline int rx_work_todo(struct xenvif *vif) { - return !skb_queue_empty(&vif->rx_queue); + return !skb_queue_empty(&vif->rx_queue) || vif->rx_event; } static inline int tx_work_todo(struct xenvif *vif) @@ -1854,8 +1756,6 @@ int xenvif_map_frontend_rings(struct xenvif *vif, rxs = (struct xen_netif_rx_sring *)addr; BACK_RING_INIT(&vif->rx, rxs, PAGE_SIZE); - vif->rx_req_cons_peek = 0; - return 0; err: @@ -1863,9 +1763,24 @@ err: return err; } +void xenvif_stop_queue(struct xenvif *vif) +{ + if (!vif->can_queue) + return; + + netif_stop_queue(vif->dev); +} + +static void xenvif_start_queue(struct xenvif *vif) +{ + if (xenvif_schedulable(vif)) + netif_wake_queue(vif->dev); +} + int xenvif_kthread(void *data) { struct xenvif *vif = data; + struct sk_buff *skb; while (!kthread_should_stop()) { wait_event_interruptible(vif->wq, @@ -1874,12 +1789,22 @@ int xenvif_kthread(void *data) if (kthread_should_stop()) break; - if (rx_work_todo(vif)) + if (!skb_queue_empty(&vif->rx_queue)) xenvif_rx_action(vif); + vif->rx_event = false; + + if (skb_queue_empty(&vif->rx_queue) && + netif_queue_stopped(vif->dev)) + xenvif_start_queue(vif); + cond_resched(); } + /* Bin any remaining skbs */ + while ((skb = skb_dequeue(&vif->rx_queue)) != NULL) + dev_kfree_skb(skb); + return 0; } -- cgit v1.2.3-70-g09d2 From b89587a7af4b2a2e0682c304224be4041e993548 Mon Sep 17 00:00:00 2001 From: Paul Durrant Date: Tue, 17 Dec 2013 11:44:35 +0000 Subject: xen-netback: add gso_segs calculation netback already has code which parses IPv4 and v6 headers to set up checksum offsets and these are always applied to GSO packets being sent from frontends. It's therefore suboptimal that GSOs are being marked SKB_GSO_DODGY to defer the gso_segs calculation when netback already has all necessary information to hand to do the calculation. This patch adds that calculation. Signed-off-by: Paul Durrant Cc: Wei Liu Cc: Ian Campbell Cc: David Vrabel Cc: Eric Dumazet Acked-by: Eric Dumazet Acked-by: Wei Liu Signed-off-by: David S. Miller --- drivers/net/xen-netback/netback.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) (limited to 'drivers/net/xen-netback/netback.c') diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 773b731e3e5..611aebee458 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -1043,10 +1043,7 @@ static int xenvif_set_skb_gso(struct xenvif *vif, } skb_shinfo(skb)->gso_size = gso->u.gso.size; - - /* Header must be checked, and gso_segs computed. */ - skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; - skb_shinfo(skb)->gso_segs = 0; + /* gso_segs will be calculated later */ return 0; } @@ -1581,6 +1578,20 @@ static int xenvif_tx_submit(struct xenvif *vif) skb_probe_transport_header(skb, 0); + /* If the packet is GSO then we will have just set up the + * transport header offset in checksum_setup so it's now + * straightforward to calculate gso_segs. + */ + if (skb_is_gso(skb)) { + int mss = skb_shinfo(skb)->gso_size; + int hdrlen = skb_transport_header(skb) - + skb_mac_header(skb) + + tcp_hdrlen(skb); + + skb_shinfo(skb)->gso_segs = + DIV_ROUND_UP(skb->len - hdrlen, mss); + } + vif->dev->stats.rx_bytes += skb->len; vif->dev->stats.rx_packets++; -- cgit v1.2.3-70-g09d2 From 11b57f90257c1d6a91cee720151b69e0c2020cf6 Mon Sep 17 00:00:00 2001 From: Paul Durrant Date: Wed, 8 Jan 2014 12:41:58 +0000 Subject: xen-netback: stop vif thread spinning if frontend is unresponsive The recent patch to improve guest receive side flow control (ca2f09f2) had a slight flaw in the wait condition for the vif thread in that any remaining skbs in the guest receive side netback internal queue would prevent the thread from sleeping. An unresponsive frontend can lead to a permanently non-empty internal queue and thus the thread will spin. In this case the thread should really sleep until the frontend becomes responsive again. This patch adds an extra flag to the vif which is set if the shared ring is full and cleared when skbs are drained into the shared ring. Thus, if the thread runs, finds the shared ring full and can make no progress the flag remains set. If the flag remains set then the thread will sleep, regardless of a non-empty queue, until the next event from the frontend. Signed-off-by: Paul Durrant Cc: Wei Liu Cc: Ian Campbell Cc: David Vrabel Acked-by: Wei Liu Signed-off-by: David S. Miller --- drivers/net/xen-netback/common.h | 1 + drivers/net/xen-netback/netback.c | 14 +++++++++----- 2 files changed, 10 insertions(+), 5 deletions(-) (limited to 'drivers/net/xen-netback/netback.c') diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h index c955fc39d69..4c76bcb9a87 100644 --- a/drivers/net/xen-netback/common.h +++ b/drivers/net/xen-netback/common.h @@ -143,6 +143,7 @@ struct xenvif { char rx_irq_name[IFNAMSIZ+4]; /* DEVNAME-rx */ struct xen_netif_rx_back_ring rx; struct sk_buff_head rx_queue; + bool rx_queue_stopped; /* Set when the RX interrupt is triggered by the frontend. * The worker thread may need to wake the queue. */ diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 4f81ac0e2f0..27385639b6e 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -476,7 +476,8 @@ static void xenvif_rx_action(struct xenvif *vif) int ret; unsigned long offset; struct skb_cb_overlay *sco; - int need_to_notify = 0; + bool need_to_notify = false; + bool ring_full = false; struct netrx_pending_operations npo = { .copy = vif->grant_copy_op, @@ -508,7 +509,8 @@ static void xenvif_rx_action(struct xenvif *vif) /* If the skb may not fit then bail out now */ if (!xenvif_rx_ring_slots_available(vif, max_slots_needed)) { skb_queue_head(&vif->rx_queue, skb); - need_to_notify = 1; + need_to_notify = true; + ring_full = true; break; } @@ -521,6 +523,8 @@ static void xenvif_rx_action(struct xenvif *vif) BUG_ON(npo.meta_prod > ARRAY_SIZE(vif->meta)); + vif->rx_queue_stopped = !npo.copy_prod && ring_full; + if (!npo.copy_prod) goto done; @@ -592,8 +596,7 @@ static void xenvif_rx_action(struct xenvif *vif) RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->rx, ret); - if (ret) - need_to_notify = 1; + need_to_notify |= !!ret; npo.meta_cons += sco->meta_slots_used; dev_kfree_skb(skb); @@ -1724,7 +1727,8 @@ static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif, static inline int rx_work_todo(struct xenvif *vif) { - return !skb_queue_empty(&vif->rx_queue) || vif->rx_event; + return (!skb_queue_empty(&vif->rx_queue) && !vif->rx_queue_stopped) || + vif->rx_event; } static inline int tx_work_todo(struct xenvif *vif) -- cgit v1.2.3-70-g09d2 From 2721637c1c0f644d7d67d0698c4a32b440d7f0f8 Mon Sep 17 00:00:00 2001 From: Paul Durrant Date: Thu, 9 Jan 2014 10:02:47 +0000 Subject: xen-netback: use new skb_checksum_setup function Use skb_checksum_setup to set up partial checksum offsets rather then a private implementation. Signed-off-by: Paul Durrant Cc: Ian Campbell Cc: Wei Liu Acked-by: Wei Liu Signed-off-by: David S. Miller --- drivers/net/xen-netback/netback.c | 260 +------------------------------------- 1 file changed, 3 insertions(+), 257 deletions(-) (limited to 'drivers/net/xen-netback/netback.c') diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 27385639b6e..6b62c3eb8e1 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -39,7 +39,6 @@ #include #include -#include #include #include @@ -1051,257 +1050,9 @@ static int xenvif_set_skb_gso(struct xenvif *vif, return 0; } -static inline int maybe_pull_tail(struct sk_buff *skb, unsigned int len, - unsigned int max) -{ - if (skb_headlen(skb) >= len) - return 0; - - /* If we need to pullup then pullup to the max, so we - * won't need to do it again. - */ - if (max > skb->len) - max = skb->len; - - if (__pskb_pull_tail(skb, max - skb_headlen(skb)) == NULL) - return -ENOMEM; - - if (skb_headlen(skb) < len) - return -EPROTO; - - return 0; -} - -/* This value should be large enough to cover a tagged ethernet header plus - * maximally sized IP and TCP or UDP headers. - */ -#define MAX_IP_HDR_LEN 128 - -static int checksum_setup_ip(struct xenvif *vif, struct sk_buff *skb, - int recalculate_partial_csum) -{ - unsigned int off; - bool fragment; - int err; - - fragment = false; - - err = maybe_pull_tail(skb, - sizeof(struct iphdr), - MAX_IP_HDR_LEN); - if (err < 0) - goto out; - - if (ip_hdr(skb)->frag_off & htons(IP_OFFSET | IP_MF)) - fragment = true; - - off = ip_hdrlen(skb); - - err = -EPROTO; - - if (fragment) - goto out; - - switch (ip_hdr(skb)->protocol) { - case IPPROTO_TCP: - err = maybe_pull_tail(skb, - off + sizeof(struct tcphdr), - MAX_IP_HDR_LEN); - if (err < 0) - goto out; - - if (!skb_partial_csum_set(skb, off, - offsetof(struct tcphdr, check))) { - err = -EPROTO; - goto out; - } - - if (recalculate_partial_csum) - tcp_hdr(skb)->check = - ~csum_tcpudp_magic(ip_hdr(skb)->saddr, - ip_hdr(skb)->daddr, - skb->len - off, - IPPROTO_TCP, 0); - break; - case IPPROTO_UDP: - err = maybe_pull_tail(skb, - off + sizeof(struct udphdr), - MAX_IP_HDR_LEN); - if (err < 0) - goto out; - - if (!skb_partial_csum_set(skb, off, - offsetof(struct udphdr, check))) { - err = -EPROTO; - goto out; - } - - if (recalculate_partial_csum) - udp_hdr(skb)->check = - ~csum_tcpudp_magic(ip_hdr(skb)->saddr, - ip_hdr(skb)->daddr, - skb->len - off, - IPPROTO_UDP, 0); - break; - default: - goto out; - } - - err = 0; - -out: - return err; -} - -/* This value should be large enough to cover a tagged ethernet header plus - * an IPv6 header, all options, and a maximal TCP or UDP header. - */ -#define MAX_IPV6_HDR_LEN 256 - -#define OPT_HDR(type, skb, off) \ - (type *)(skb_network_header(skb) + (off)) - -static int checksum_setup_ipv6(struct xenvif *vif, struct sk_buff *skb, - int recalculate_partial_csum) -{ - int err; - u8 nexthdr; - unsigned int off; - unsigned int len; - bool fragment; - bool done; - - fragment = false; - done = false; - - off = sizeof(struct ipv6hdr); - - err = maybe_pull_tail(skb, off, MAX_IPV6_HDR_LEN); - if (err < 0) - goto out; - - nexthdr = ipv6_hdr(skb)->nexthdr; - - len = sizeof(struct ipv6hdr) + ntohs(ipv6_hdr(skb)->payload_len); - while (off <= len && !done) { - switch (nexthdr) { - case IPPROTO_DSTOPTS: - case IPPROTO_HOPOPTS: - case IPPROTO_ROUTING: { - struct ipv6_opt_hdr *hp; - - err = maybe_pull_tail(skb, - off + - sizeof(struct ipv6_opt_hdr), - MAX_IPV6_HDR_LEN); - if (err < 0) - goto out; - - hp = OPT_HDR(struct ipv6_opt_hdr, skb, off); - nexthdr = hp->nexthdr; - off += ipv6_optlen(hp); - break; - } - case IPPROTO_AH: { - struct ip_auth_hdr *hp; - - err = maybe_pull_tail(skb, - off + - sizeof(struct ip_auth_hdr), - MAX_IPV6_HDR_LEN); - if (err < 0) - goto out; - - hp = OPT_HDR(struct ip_auth_hdr, skb, off); - nexthdr = hp->nexthdr; - off += ipv6_authlen(hp); - break; - } - case IPPROTO_FRAGMENT: { - struct frag_hdr *hp; - - err = maybe_pull_tail(skb, - off + - sizeof(struct frag_hdr), - MAX_IPV6_HDR_LEN); - if (err < 0) - goto out; - - hp = OPT_HDR(struct frag_hdr, skb, off); - - if (hp->frag_off & htons(IP6_OFFSET | IP6_MF)) - fragment = true; - - nexthdr = hp->nexthdr; - off += sizeof(struct frag_hdr); - break; - } - default: - done = true; - break; - } - } - - err = -EPROTO; - - if (!done || fragment) - goto out; - - switch (nexthdr) { - case IPPROTO_TCP: - err = maybe_pull_tail(skb, - off + sizeof(struct tcphdr), - MAX_IPV6_HDR_LEN); - if (err < 0) - goto out; - - if (!skb_partial_csum_set(skb, off, - offsetof(struct tcphdr, check))) { - err = -EPROTO; - goto out; - } - - if (recalculate_partial_csum) - tcp_hdr(skb)->check = - ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, - &ipv6_hdr(skb)->daddr, - skb->len - off, - IPPROTO_TCP, 0); - break; - case IPPROTO_UDP: - err = maybe_pull_tail(skb, - off + sizeof(struct udphdr), - MAX_IPV6_HDR_LEN); - if (err < 0) - goto out; - - if (!skb_partial_csum_set(skb, off, - offsetof(struct udphdr, check))) { - err = -EPROTO; - goto out; - } - - if (recalculate_partial_csum) - udp_hdr(skb)->check = - ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, - &ipv6_hdr(skb)->daddr, - skb->len - off, - IPPROTO_UDP, 0); - break; - default: - goto out; - } - - err = 0; - -out: - return err; -} - static int checksum_setup(struct xenvif *vif, struct sk_buff *skb) { - int err = -EPROTO; - int recalculate_partial_csum = 0; + bool recalculate_partial_csum = false; /* A GSO SKB must be CHECKSUM_PARTIAL. However some buggy * peers can fail to set NETRXF_csum_blank when sending a GSO @@ -1311,19 +1062,14 @@ static int checksum_setup(struct xenvif *vif, struct sk_buff *skb) if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) { vif->rx_gso_checksum_fixup++; skb->ip_summed = CHECKSUM_PARTIAL; - recalculate_partial_csum = 1; + recalculate_partial_csum = true; } /* A non-CHECKSUM_PARTIAL SKB does not require setup. */ if (skb->ip_summed != CHECKSUM_PARTIAL) return 0; - if (skb->protocol == htons(ETH_P_IP)) - err = checksum_setup_ip(vif, skb, recalculate_partial_csum); - else if (skb->protocol == htons(ETH_P_IPV6)) - err = checksum_setup_ipv6(vif, skb, recalculate_partial_csum); - - return err; + return skb_checksum_setup(skb, recalculate_partial_csum); } static bool tx_credit_exceeded(struct xenvif *vif, unsigned size) -- cgit v1.2.3-70-g09d2