openvswitch: Allow OVS_USERSPACE_ATTR_USERDATA to be variable length.

Until now, the optional OVS_USERSPACE_ATTR_USERDATA attribute had to be
exactly 64 bits long, if it was present.  However, 64 bits is not enough
space to associate as much information with a flow as would be convenient
for some userspace features now under development.  This commit generalizes
the attribute, allowing it to be any length.

This generalization is backward-compatible: if userspace only uses 64-bit
attributes, then it will not see any change in behavior.

CC: Romain Lenglet <rlenglet@vmware.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
This commit is contained in:
Ben Pfaff 2013-02-15 17:29:22 -08:00 committed by Jesse Gross
parent 14408dba84
commit 4490108b4a
3 changed files with 13 additions and 11 deletions

View File

@ -127,7 +127,8 @@ enum ovs_packet_cmd {
* for %OVS_PACKET_CMD_EXECUTE. It has nested %OVS_ACTION_ATTR_* attributes.
* @OVS_PACKET_ATTR_USERDATA: Present for an %OVS_PACKET_CMD_ACTION
* notification if the %OVS_ACTION_ATTR_USERSPACE action specified an
* %OVS_USERSPACE_ATTR_USERDATA attribute.
* %OVS_USERSPACE_ATTR_USERDATA attribute, with the same length and content
* specified there.
*
* These attributes follow the &struct ovs_header within the Generic Netlink
* payload for %OVS_PACKET_* commands.
@ -137,7 +138,7 @@ enum ovs_packet_attr {
OVS_PACKET_ATTR_PACKET, /* Packet data. */
OVS_PACKET_ATTR_KEY, /* Nested OVS_KEY_ATTR_* attributes. */
OVS_PACKET_ATTR_ACTIONS, /* Nested OVS_ACTION_ATTR_* attributes. */
OVS_PACKET_ATTR_USERDATA, /* u64 OVS_ACTION_ATTR_USERSPACE arg. */
OVS_PACKET_ATTR_USERDATA, /* OVS_ACTION_ATTR_USERSPACE arg. */
__OVS_PACKET_ATTR_MAX
};
@ -389,13 +390,13 @@ enum ovs_sample_attr {
* enum ovs_userspace_attr - Attributes for %OVS_ACTION_ATTR_USERSPACE action.
* @OVS_USERSPACE_ATTR_PID: u32 Netlink PID to which the %OVS_PACKET_CMD_ACTION
* message should be sent. Required.
* @OVS_USERSPACE_ATTR_USERDATA: If present, its u64 argument is copied to the
* %OVS_PACKET_CMD_ACTION message as %OVS_PACKET_ATTR_USERDATA,
* @OVS_USERSPACE_ATTR_USERDATA: If present, its variable-length argument is
* copied to the %OVS_PACKET_CMD_ACTION message as %OVS_PACKET_ATTR_USERDATA.
*/
enum ovs_userspace_attr {
OVS_USERSPACE_ATTR_UNSPEC,
OVS_USERSPACE_ATTR_PID, /* u32 Netlink PID to receive upcalls. */
OVS_USERSPACE_ATTR_USERDATA, /* u64 optional user-specified cookie. */
OVS_USERSPACE_ATTR_USERDATA, /* Optional user-specified cookie. */
__OVS_USERSPACE_ATTR_MAX
};

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@ -370,8 +370,8 @@ static int queue_userspace_packet(struct net *net, int dp_ifindex,
len = sizeof(struct ovs_header);
len += nla_total_size(skb->len);
len += nla_total_size(FLOW_BUFSIZE);
if (upcall_info->cmd == OVS_PACKET_CMD_ACTION)
len += nla_total_size(8);
if (upcall_info->userdata)
len += NLA_ALIGN(upcall_info->userdata->nla_len);
user_skb = genlmsg_new(len, GFP_ATOMIC);
if (!user_skb) {
@ -388,8 +388,9 @@ static int queue_userspace_packet(struct net *net, int dp_ifindex,
nla_nest_end(user_skb, nla);
if (upcall_info->userdata)
nla_put_u64(user_skb, OVS_PACKET_ATTR_USERDATA,
nla_get_u64(upcall_info->userdata));
__nla_put(user_skb, OVS_PACKET_ATTR_USERDATA,
nla_len(upcall_info->userdata),
nla_data(upcall_info->userdata));
nla = __nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, skb->len);
@ -544,7 +545,7 @@ static int validate_userspace(const struct nlattr *attr)
{
static const struct nla_policy userspace_policy[OVS_USERSPACE_ATTR_MAX + 1] = {
[OVS_USERSPACE_ATTR_PID] = {.type = NLA_U32 },
[OVS_USERSPACE_ATTR_USERDATA] = {.type = NLA_U64 },
[OVS_USERSPACE_ATTR_USERDATA] = {.type = NLA_UNSPEC },
};
struct nlattr *a[OVS_USERSPACE_ATTR_MAX + 1];
int error;

View File

@ -119,7 +119,7 @@ struct ovs_skb_cb {
* struct dp_upcall - metadata to include with a packet to send to userspace
* @cmd: One of %OVS_PACKET_CMD_*.
* @key: Becomes %OVS_PACKET_ATTR_KEY. Must be nonnull.
* @userdata: If nonnull, its u64 value is extracted and passed to userspace as
* @userdata: If nonnull, its variable-length value is passed to userspace as
* %OVS_PACKET_ATTR_USERDATA.
* @pid: Netlink PID to which packet should be sent. If @pid is 0 then no
* packet is sent and the packet is accounted in the datapath's @n_lost