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author | David S. Miller <davem@davemloft.net> | 2019-04-11 11:10:34 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2019-04-11 11:10:34 -0700 |
commit | 9a4dda81f1d377ff98e82f019e07a6f2a1db34f3 (patch) | |
tree | 607673dfc7cbfa106a6ae87456502a475c9beee8 | |
parent | 796fff0c12b238f57868938577abc495b5b8c3aa (diff) | |
parent | 1f227d16083b2e280b7dde4ca78883d75593f2fd (diff) | |
download | lwn-9a4dda81f1d377ff98e82f019e07a6f2a1db34f3.tar.gz lwn-9a4dda81f1d377ff98e82f019e07a6f2a1db34f3.zip |
Merge branch 'thunderx-xdp-mtu'
Matteo Croce says:
====================
Fix thunderx MTU with XDP
The thunderx driver can't use XDP with all MTU values.
This patches sets the right MTU values, and add a check to avoid setting
a wrong value which will not function.
v3: Fix a copy-paste from two functions, tested on proper hardware:
2: enP2p1s0v0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
link/ether 1c:1b:0d:0d:52:a4 brd ff:ff:ff:ff:ff:ff
[ 787.019730] nicvf 0002:01:00.1 enP2p1s0v0: Jumbo frames not yet supported with XDP, current MTU 1800.
RTNETLINK answers: Operation not supported
[ 800.574568] nicvf 0002:01:00.1 enP2p1s0v0: Link is Up 10000 Mbps Full duplex
[ 807.248321] nicvf 0002:01:00.1 enP2p1s0v0: Jumbo frames not yet supported with XDP, current MTU 1500.
RTNETLINK answers: Invalid argument
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | drivers/net/ethernet/cavium/thunder/nicvf_main.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c index 28eac9056211..c032bef1b776 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c +++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c @@ -32,6 +32,13 @@ #define DRV_NAME "nicvf" #define DRV_VERSION "1.0" +/* NOTE: Packets bigger than 1530 are split across multiple pages and XDP needs + * the buffer to be contiguous. Allow XDP to be set up only if we don't exceed + * this value, keeping headroom for the 14 byte Ethernet header and two + * VLAN tags (for QinQ) + */ +#define MAX_XDP_MTU (1530 - ETH_HLEN - VLAN_HLEN * 2) + /* Supported devices */ static const struct pci_device_id nicvf_id_table[] = { { PCI_DEVICE_SUB(PCI_VENDOR_ID_CAVIUM, @@ -1582,6 +1589,15 @@ static int nicvf_change_mtu(struct net_device *netdev, int new_mtu) struct nicvf *nic = netdev_priv(netdev); int orig_mtu = netdev->mtu; + /* For now just support only the usual MTU sized frames, + * plus some headroom for VLAN, QinQ. + */ + if (nic->xdp_prog && new_mtu > MAX_XDP_MTU) { + netdev_warn(netdev, "Jumbo frames not yet supported with XDP, current MTU %d.\n", + netdev->mtu); + return -EINVAL; + } + netdev->mtu = new_mtu; if (!netif_running(netdev)) @@ -1830,8 +1846,10 @@ static int nicvf_xdp_setup(struct nicvf *nic, struct bpf_prog *prog) bool bpf_attached = false; int ret = 0; - /* For now just support only the usual MTU sized frames */ - if (prog && (dev->mtu > 1500)) { + /* For now just support only the usual MTU sized frames, + * plus some headroom for VLAN, QinQ. + */ + if (prog && dev->mtu > MAX_XDP_MTU) { netdev_warn(dev, "Jumbo frames not yet supported with XDP, current MTU %d.\n", dev->mtu); return -EOPNOTSUPP; |