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batman-adv: return netdev status in the TX path
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Return the proper netdev TX status along the TX path so that the tp_meter
can understand when the queue is full and should stop sending packets.

Signed-off-by: Antonio Quartulli <[email protected]>
Signed-off-by: Sven Eckelmann <[email protected]>
Signed-off-by: Marek Lindner <[email protected]>
Signed-off-by: Simon Wunderlich <[email protected]>
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@ordex @simonwunderlich
ordex authored and simonwunderlich committed Jul 4, 2016
1 parent 5da0aef commit f50ca95
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Showing 5 changed files with 68 additions and 44 deletions.
41 changes: 25 additions & 16 deletions net/batman-adv/fragmentation.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -433,11 +433,12 @@ static struct sk_buff *batadv_frag_create(struct sk_buff *skb,
* @orig_node: final destination of the created fragments
* @neigh_node: next-hop of the created fragments
*
* Return: true on success, false otherwise.
* Return: the netdev tx status or -1 in case of error.
* When -1 is returned the skb is not consumed.
*/
bool batadv_frag_send_packet(struct sk_buff *skb,
struct batadv_orig_node *orig_node,
struct batadv_neigh_node *neigh_node)
int batadv_frag_send_packet(struct sk_buff *skb,
struct batadv_orig_node *orig_node,
struct batadv_neigh_node *neigh_node)
{
struct batadv_priv *bat_priv;
struct batadv_hard_iface *primary_if = NULL;
Expand All @@ -446,7 +447,7 @@ bool batadv_frag_send_packet(struct sk_buff *skb,
unsigned int mtu = neigh_node->if_incoming->net_dev->mtu;
unsigned int header_size = sizeof(frag_header);
unsigned int max_fragment_size, max_packet_size;
bool ret = false;
int ret = -1;

/* To avoid merge and refragmentation at next-hops we never send
* fragments larger than BATADV_FRAG_MAX_FRAG_SIZE
Expand All @@ -457,12 +458,12 @@ bool batadv_frag_send_packet(struct sk_buff *skb,

/* Don't even try to fragment, if we need more than 16 fragments */
if (skb->len > max_packet_size)
goto out_err;
goto out;

bat_priv = orig_node->bat_priv;
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
goto out_err;
goto out;

/* Create one header to be copied to all fragments */
frag_header.packet_type = BATADV_UNICAST_FRAG;
Expand All @@ -488,35 +489,43 @@ bool batadv_frag_send_packet(struct sk_buff *skb,
while (skb->len > max_fragment_size) {
skb_fragment = batadv_frag_create(skb, &frag_header, mtu);
if (!skb_fragment)
goto out_err;
goto out;

batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_TX);
batadv_add_counter(bat_priv, BATADV_CNT_FRAG_TX_BYTES,
skb_fragment->len + ETH_HLEN);
batadv_send_unicast_skb(skb_fragment, neigh_node);
ret = batadv_send_unicast_skb(skb_fragment, neigh_node);
if (ret != NET_XMIT_SUCCESS) {
/* return -1 so that the caller can free the original
* skb
*/
ret = -1;
goto out;
}

frag_header.no++;

/* The initial check in this function should cover this case */
if (frag_header.no == BATADV_FRAG_MAX_FRAGMENTS - 1)
goto out_err;
if (frag_header.no == BATADV_FRAG_MAX_FRAGMENTS - 1) {
ret = -1;
goto out;
}
}

/* Make room for the fragment header. */
if (batadv_skb_head_push(skb, header_size) < 0 ||
pskb_expand_head(skb, header_size + ETH_HLEN, 0, GFP_ATOMIC) < 0)
goto out_err;
goto out;

memcpy(skb->data, &frag_header, header_size);

/* Send the last fragment */
batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_TX);
batadv_add_counter(bat_priv, BATADV_CNT_FRAG_TX_BYTES,
skb->len + ETH_HLEN);
batadv_send_unicast_skb(skb, neigh_node);
ret = batadv_send_unicast_skb(skb, neigh_node);

ret = true;

out_err:
out:
if (primary_if)
batadv_hardif_put(primary_if);

Expand Down
6 changes: 3 additions & 3 deletions net/batman-adv/fragmentation.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -34,9 +34,9 @@ bool batadv_frag_skb_fwd(struct sk_buff *skb,
struct batadv_orig_node *orig_node_src);
bool batadv_frag_skb_buffer(struct sk_buff **skb,
struct batadv_orig_node *orig_node);
bool batadv_frag_send_packet(struct sk_buff *skb,
struct batadv_orig_node *orig_node,
struct batadv_neigh_node *neigh_node);
int batadv_frag_send_packet(struct sk_buff *skb,
struct batadv_orig_node *orig_node,
struct batadv_neigh_node *neigh_node);

/**
* batadv_frag_check_entry - check if a list of fragments has timed out
Expand Down
25 changes: 14 additions & 11 deletions net/batman-adv/routing.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -270,8 +270,10 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
icmph->ttl = BATADV_TTL;

res = batadv_send_skb_to_orig(skb, orig_node, NULL);
if (res != NET_XMIT_DROP)
ret = NET_RX_SUCCESS;
if (res == -1)
goto out;

ret = NET_RX_SUCCESS;

break;
default:
Expand All @@ -292,7 +294,7 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
struct batadv_hard_iface *primary_if = NULL;
struct batadv_orig_node *orig_node = NULL;
struct batadv_icmp_packet *icmp_packet;
int ret = NET_RX_DROP;
int res, ret = NET_RX_DROP;

icmp_packet = (struct batadv_icmp_packet *)skb->data;

Expand Down Expand Up @@ -323,7 +325,8 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
icmp_packet->ttl = BATADV_TTL;

if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
res = batadv_send_skb_to_orig(skb, orig_node, NULL);
if (res != -1)
ret = NET_RX_SUCCESS;

out:
Expand All @@ -343,7 +346,7 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
struct ethhdr *ethhdr;
struct batadv_orig_node *orig_node = NULL;
int hdr_size = sizeof(struct batadv_icmp_header);
int ret = NET_RX_DROP;
int res, ret = NET_RX_DROP;

/* drop packet if it has not necessary minimum size */
if (unlikely(!pskb_may_pull(skb, hdr_size)))
Expand Down Expand Up @@ -409,7 +412,8 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
icmph->ttl--;

/* route it */
if (batadv_send_skb_to_orig(skb, orig_node, recv_if) != NET_XMIT_DROP)
res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
if (res != -1)
ret = NET_RX_SUCCESS;

out:
Expand Down Expand Up @@ -646,20 +650,19 @@ static int batadv_route_unicast_packet(struct sk_buff *skb,

len = skb->len;
res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
if (res == -1)
goto out;

/* translate transmit result into receive result */
if (res == NET_XMIT_SUCCESS) {
/* skb was transmitted and consumed */
batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
len + ETH_HLEN);

ret = NET_RX_SUCCESS;
} else if (res == -EINPROGRESS) {
/* skb was buffered and consumed */
ret = NET_RX_SUCCESS;
}

ret = NET_RX_SUCCESS;

out:
if (orig_node)
batadv_orig_node_put(orig_node);
Expand Down
36 changes: 23 additions & 13 deletions net/batman-adv/send.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -20,6 +20,7 @@

#include <linux/atomic.h>
#include <linux/byteorder/generic.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/if.h>
Expand Down Expand Up @@ -72,6 +73,7 @@ int batadv_send_skb_packet(struct sk_buff *skb,
{
struct batadv_priv *bat_priv;
struct ethhdr *ethhdr;
int ret;

bat_priv = netdev_priv(hard_iface->soft_iface);

Expand Down Expand Up @@ -109,8 +111,15 @@ int batadv_send_skb_packet(struct sk_buff *skb,
/* dev_queue_xmit() returns a negative result on error. However on
* congestion and traffic shaping, it drops and returns NET_XMIT_DROP
* (which is > 0). This will not be treated as an error.
*
* a negative value cannot be returned because it could be interepreted
* as not consumed skb by callers of batadv_send_skb_to_orig.
*/
return dev_queue_xmit(skb);
ret = dev_queue_xmit(skb);
if (ret < 0)
ret = NET_XMIT_DROP;

return ret;
send_skb_err:
kfree_skb(skb);
return NET_XMIT_DROP;
Expand Down Expand Up @@ -156,16 +165,19 @@ int batadv_send_unicast_skb(struct sk_buff *skb,
* host, NULL can be passed as recv_if and no interface alternating is
* attempted.
*
* Return: NET_XMIT_SUCCESS on success, NET_XMIT_DROP on failure, or
* -EINPROGRESS if the skb is buffered for later transmit.
* Return: -1 on failure (and the skb is not consumed), -EINPROGRESS if the
* skb is buffered for later transmit or the NET_XMIT status returned by the
* lower routine if the packet has been passed down.
*
* If the returning value is not -1 the skb has been consumed.
*/
int batadv_send_skb_to_orig(struct sk_buff *skb,
struct batadv_orig_node *orig_node,
struct batadv_hard_iface *recv_if)
{
struct batadv_priv *bat_priv = orig_node->bat_priv;
struct batadv_neigh_node *neigh_node;
int ret = NET_XMIT_DROP;
int ret = -1;

/* batadv_find_router() increases neigh_nodes refcount if found. */
neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
Expand All @@ -178,8 +190,7 @@ int batadv_send_skb_to_orig(struct sk_buff *skb,
if (atomic_read(&bat_priv->fragmentation) &&
skb->len > neigh_node->if_incoming->net_dev->mtu) {
/* Fragment and send packet. */
if (batadv_frag_send_packet(skb, orig_node, neigh_node))
ret = NET_XMIT_SUCCESS;
ret = batadv_frag_send_packet(skb, orig_node, neigh_node);

goto out;
}
Expand All @@ -188,12 +199,10 @@ int batadv_send_skb_to_orig(struct sk_buff *skb,
* (i.e. being forwarded). If the packet originates from this node or if
* network coding fails, then send the packet as usual.
*/
if (recv_if && batadv_nc_skb_forward(skb, neigh_node)) {
if (recv_if && batadv_nc_skb_forward(skb, neigh_node))
ret = -EINPROGRESS;
} else {
batadv_send_unicast_skb(skb, neigh_node);
ret = NET_XMIT_SUCCESS;
}
else
ret = batadv_send_unicast_skb(skb, neigh_node);

out:
if (neigh_node)
Expand Down Expand Up @@ -319,7 +328,7 @@ int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
{
struct batadv_unicast_packet *unicast_packet;
struct ethhdr *ethhdr;
int ret = NET_XMIT_DROP;
int res, ret = NET_XMIT_DROP;

if (!orig_node)
goto out;
Expand Down Expand Up @@ -356,7 +365,8 @@ int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest, vid))
unicast_packet->ttvn = unicast_packet->ttvn - 1;

if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
res = batadv_send_skb_to_orig(skb, orig_node, NULL);
if (res != -1)
ret = NET_XMIT_SUCCESS;

out:
Expand Down
4 changes: 3 additions & 1 deletion net/batman-adv/tvlv.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -591,6 +591,7 @@ void batadv_tvlv_unicast_send(struct batadv_priv *bat_priv, u8 *src,
unsigned char *tvlv_buff;
unsigned int tvlv_len;
ssize_t hdr_len = sizeof(*unicast_tvlv_packet);
int res;

orig_node = batadv_orig_hash_find(bat_priv, dst);
if (!orig_node)
Expand Down Expand Up @@ -623,7 +624,8 @@ void batadv_tvlv_unicast_send(struct batadv_priv *bat_priv, u8 *src,
tvlv_buff += sizeof(*tvlv_hdr);
memcpy(tvlv_buff, tvlv_value, tvlv_value_len);

if (batadv_send_skb_to_orig(skb, orig_node, NULL) == NET_XMIT_DROP)
res = batadv_send_skb_to_orig(skb, orig_node, NULL);
if (res == -1)
kfree_skb(skb);
out:
batadv_orig_node_put(orig_node);
Expand Down

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