tmp_suning_uos_patched/net/xdp/xsk_diag.c
Björn Töpel 2b43470add xsk: Introduce AF_XDP buffer allocation API
In order to simplify AF_XDP zero-copy enablement for NIC driver
developers, a new AF_XDP buffer allocation API is added. The
implementation is based on a single core (single producer/consumer)
buffer pool for the AF_XDP UMEM.

A buffer is allocated using the xsk_buff_alloc() function, and
returned using xsk_buff_free(). If a buffer is disassociated with the
pool, e.g. when a buffer is passed to an AF_XDP socket, a buffer is
said to be released. Currently, the release function is only used by
the AF_XDP internals and not visible to the driver.

Drivers using this API should register the XDP memory model with the
new MEM_TYPE_XSK_BUFF_POOL type.

The API is defined in net/xdp_sock_drv.h.

The buffer type is struct xdp_buff, and follows the lifetime of
regular xdp_buffs, i.e.  the lifetime of an xdp_buff is restricted to
a NAPI context. In other words, the API is not replacing xdp_frames.

In addition to introducing the API and implementations, the AF_XDP
core is migrated to use the new APIs.

rfc->v1: Fixed build errors/warnings for m68k and riscv. (kbuild test
         robot)
         Added headroom/chunk size getter. (Maxim/Björn)

v1->v2: Swapped SoBs. (Maxim)

v2->v3: Initialize struct xdp_buff member frame_sz. (Björn)
        Add API to query the DMA address of a frame. (Maxim)
        Do DMA sync for CPU till the end of the frame to handle
        possible growth (frame_sz). (Maxim)

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200520192103.355233-6-bjorn.topel@gmail.com
2020-05-21 17:31:26 -07:00

195 lines
4.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* XDP sockets monitoring support
*
* Copyright(c) 2019 Intel Corporation.
*
* Author: Björn Töpel <bjorn.topel@intel.com>
*/
#include <linux/module.h>
#include <net/xdp_sock.h>
#include <linux/xdp_diag.h>
#include <linux/sock_diag.h>
#include "xsk_queue.h"
#include "xsk.h"
static int xsk_diag_put_info(const struct xdp_sock *xs, struct sk_buff *nlskb)
{
struct xdp_diag_info di = {};
di.ifindex = xs->dev ? xs->dev->ifindex : 0;
di.queue_id = xs->queue_id;
return nla_put(nlskb, XDP_DIAG_INFO, sizeof(di), &di);
}
static int xsk_diag_put_ring(const struct xsk_queue *queue, int nl_type,
struct sk_buff *nlskb)
{
struct xdp_diag_ring dr = {};
dr.entries = queue->nentries;
return nla_put(nlskb, nl_type, sizeof(dr), &dr);
}
static int xsk_diag_put_rings_cfg(const struct xdp_sock *xs,
struct sk_buff *nlskb)
{
int err = 0;
if (xs->rx)
err = xsk_diag_put_ring(xs->rx, XDP_DIAG_RX_RING, nlskb);
if (!err && xs->tx)
err = xsk_diag_put_ring(xs->tx, XDP_DIAG_TX_RING, nlskb);
return err;
}
static int xsk_diag_put_umem(const struct xdp_sock *xs, struct sk_buff *nlskb)
{
struct xdp_umem *umem = xs->umem;
struct xdp_diag_umem du = {};
int err;
if (!umem)
return 0;
du.id = umem->id;
du.size = umem->size;
du.num_pages = umem->npgs;
du.chunk_size = umem->chunk_size;
du.headroom = umem->headroom;
du.ifindex = umem->dev ? umem->dev->ifindex : 0;
du.queue_id = umem->queue_id;
du.flags = 0;
if (umem->zc)
du.flags |= XDP_DU_F_ZEROCOPY;
du.refs = refcount_read(&umem->users);
err = nla_put(nlskb, XDP_DIAG_UMEM, sizeof(du), &du);
if (!err && umem->fq)
err = xsk_diag_put_ring(umem->fq, XDP_DIAG_UMEM_FILL_RING, nlskb);
if (!err && umem->cq) {
err = xsk_diag_put_ring(umem->cq, XDP_DIAG_UMEM_COMPLETION_RING,
nlskb);
}
return err;
}
static int xsk_diag_fill(struct sock *sk, struct sk_buff *nlskb,
struct xdp_diag_req *req,
struct user_namespace *user_ns,
u32 portid, u32 seq, u32 flags, int sk_ino)
{
struct xdp_sock *xs = xdp_sk(sk);
struct xdp_diag_msg *msg;
struct nlmsghdr *nlh;
nlh = nlmsg_put(nlskb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*msg),
flags);
if (!nlh)
return -EMSGSIZE;
msg = nlmsg_data(nlh);
memset(msg, 0, sizeof(*msg));
msg->xdiag_family = AF_XDP;
msg->xdiag_type = sk->sk_type;
msg->xdiag_ino = sk_ino;
sock_diag_save_cookie(sk, msg->xdiag_cookie);
mutex_lock(&xs->mutex);
if ((req->xdiag_show & XDP_SHOW_INFO) && xsk_diag_put_info(xs, nlskb))
goto out_nlmsg_trim;
if ((req->xdiag_show & XDP_SHOW_INFO) &&
nla_put_u32(nlskb, XDP_DIAG_UID,
from_kuid_munged(user_ns, sock_i_uid(sk))))
goto out_nlmsg_trim;
if ((req->xdiag_show & XDP_SHOW_RING_CFG) &&
xsk_diag_put_rings_cfg(xs, nlskb))
goto out_nlmsg_trim;
if ((req->xdiag_show & XDP_SHOW_UMEM) &&
xsk_diag_put_umem(xs, nlskb))
goto out_nlmsg_trim;
if ((req->xdiag_show & XDP_SHOW_MEMINFO) &&
sock_diag_put_meminfo(sk, nlskb, XDP_DIAG_MEMINFO))
goto out_nlmsg_trim;
mutex_unlock(&xs->mutex);
nlmsg_end(nlskb, nlh);
return 0;
out_nlmsg_trim:
mutex_unlock(&xs->mutex);
nlmsg_cancel(nlskb, nlh);
return -EMSGSIZE;
}
static int xsk_diag_dump(struct sk_buff *nlskb, struct netlink_callback *cb)
{
struct xdp_diag_req *req = nlmsg_data(cb->nlh);
struct net *net = sock_net(nlskb->sk);
int num = 0, s_num = cb->args[0];
struct sock *sk;
mutex_lock(&net->xdp.lock);
sk_for_each(sk, &net->xdp.list) {
if (!net_eq(sock_net(sk), net))
continue;
if (num++ < s_num)
continue;
if (xsk_diag_fill(sk, nlskb, req,
sk_user_ns(NETLINK_CB(cb->skb).sk),
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, NLM_F_MULTI,
sock_i_ino(sk)) < 0) {
num--;
break;
}
}
mutex_unlock(&net->xdp.lock);
cb->args[0] = num;
return nlskb->len;
}
static int xsk_diag_handler_dump(struct sk_buff *nlskb, struct nlmsghdr *hdr)
{
struct netlink_dump_control c = { .dump = xsk_diag_dump };
int hdrlen = sizeof(struct xdp_diag_req);
struct net *net = sock_net(nlskb->sk);
if (nlmsg_len(hdr) < hdrlen)
return -EINVAL;
if (!(hdr->nlmsg_flags & NLM_F_DUMP))
return -EOPNOTSUPP;
return netlink_dump_start(net->diag_nlsk, nlskb, hdr, &c);
}
static const struct sock_diag_handler xsk_diag_handler = {
.family = AF_XDP,
.dump = xsk_diag_handler_dump,
};
static int __init xsk_diag_init(void)
{
return sock_diag_register(&xsk_diag_handler);
}
static void __exit xsk_diag_exit(void)
{
sock_diag_unregister(&xsk_diag_handler);
}
module_init(xsk_diag_init);
module_exit(xsk_diag_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, AF_XDP);