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Diffstat (limited to 'tools/lib/bpf/netlink.c')
-rw-r--r--tools/lib/bpf/netlink.c180
1 files changed, 140 insertions, 40 deletions
diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c
index 39f25e09b51e..cbc8967d5402 100644
--- a/tools/lib/bpf/netlink.c
+++ b/tools/lib/bpf/netlink.c
@@ -87,29 +87,75 @@ enum {
NL_DONE,
};
+static int netlink_recvmsg(int sock, struct msghdr *mhdr, int flags)
+{
+ int len;
+
+ do {
+ len = recvmsg(sock, mhdr, flags);
+ } while (len < 0 && (errno == EINTR || errno == EAGAIN));
+
+ if (len < 0)
+ return -errno;
+ return len;
+}
+
+static int alloc_iov(struct iovec *iov, int len)
+{
+ void *nbuf;
+
+ nbuf = realloc(iov->iov_base, len);
+ if (!nbuf)
+ return -ENOMEM;
+
+ iov->iov_base = nbuf;
+ iov->iov_len = len;
+ return 0;
+}
+
static int libbpf_netlink_recv(int sock, __u32 nl_pid, int seq,
__dump_nlmsg_t _fn, libbpf_dump_nlmsg_t fn,
void *cookie)
{
+ struct iovec iov = {};
+ struct msghdr mhdr = {
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ };
bool multipart = true;
struct nlmsgerr *err;
struct nlmsghdr *nh;
- char buf[4096];
int len, ret;
+ ret = alloc_iov(&iov, 4096);
+ if (ret)
+ goto done;
+
while (multipart) {
start:
multipart = false;
- len = recv(sock, buf, sizeof(buf), 0);
+ len = netlink_recvmsg(sock, &mhdr, MSG_PEEK | MSG_TRUNC);
if (len < 0) {
- ret = -errno;
+ ret = len;
+ goto done;
+ }
+
+ if (len > iov.iov_len) {
+ ret = alloc_iov(&iov, len);
+ if (ret)
+ goto done;
+ }
+
+ len = netlink_recvmsg(sock, &mhdr, 0);
+ if (len < 0) {
+ ret = len;
goto done;
}
if (len == 0)
break;
- for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, len);
+ for (nh = (struct nlmsghdr *)iov.iov_base; NLMSG_OK(nh, len);
nh = NLMSG_NEXT(nh, len)) {
if (nh->nlmsg_pid != nl_pid) {
ret = -LIBBPF_ERRNO__WRNGPID;
@@ -130,7 +176,8 @@ start:
libbpf_nla_dump_errormsg(nh);
goto done;
case NLMSG_DONE:
- return 0;
+ ret = 0;
+ goto done;
default:
break;
}
@@ -142,15 +189,17 @@ start:
case NL_NEXT:
goto start;
case NL_DONE:
- return 0;
+ ret = 0;
+ goto done;
default:
- return ret;
+ goto done;
}
}
}
}
ret = 0;
done:
+ free(iov.iov_base);
return ret;
}
@@ -217,6 +266,28 @@ static int __bpf_set_link_xdp_fd_replace(int ifindex, int fd, int old_fd,
return libbpf_netlink_send_recv(&req, NULL, NULL, NULL);
}
+int bpf_xdp_attach(int ifindex, int prog_fd, __u32 flags, const struct bpf_xdp_attach_opts *opts)
+{
+ int old_prog_fd, err;
+
+ if (!OPTS_VALID(opts, bpf_xdp_attach_opts))
+ return libbpf_err(-EINVAL);
+
+ old_prog_fd = OPTS_GET(opts, old_prog_fd, 0);
+ if (old_prog_fd)
+ flags |= XDP_FLAGS_REPLACE;
+ else
+ old_prog_fd = -1;
+
+ err = __bpf_set_link_xdp_fd_replace(ifindex, prog_fd, old_prog_fd, flags);
+ return libbpf_err(err);
+}
+
+int bpf_xdp_detach(int ifindex, __u32 flags, const struct bpf_xdp_attach_opts *opts)
+{
+ return bpf_xdp_attach(ifindex, -1, flags, opts);
+}
+
int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags,
const struct bpf_xdp_set_link_opts *opts)
{
@@ -303,69 +374,98 @@ static int get_xdp_info(void *cookie, void *msg, struct nlattr **tb)
return 0;
}
-int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
- size_t info_size, __u32 flags)
+int bpf_xdp_query(int ifindex, int xdp_flags, struct bpf_xdp_query_opts *opts)
{
- struct xdp_id_md xdp_id = {};
- __u32 mask;
- int ret;
struct libbpf_nla_req req = {
.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
.nh.nlmsg_type = RTM_GETLINK,
.nh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
.ifinfo.ifi_family = AF_PACKET,
};
+ struct xdp_id_md xdp_id = {};
+ int err;
- if (flags & ~XDP_FLAGS_MASK || !info_size)
+ if (!OPTS_VALID(opts, bpf_xdp_query_opts))
+ return libbpf_err(-EINVAL);
+
+ if (xdp_flags & ~XDP_FLAGS_MASK)
return libbpf_err(-EINVAL);
/* Check whether the single {HW,DRV,SKB} mode is set */
- flags &= (XDP_FLAGS_SKB_MODE | XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE);
- mask = flags - 1;
- if (flags && flags & mask)
+ xdp_flags &= XDP_FLAGS_SKB_MODE | XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE;
+ if (xdp_flags & (xdp_flags - 1))
return libbpf_err(-EINVAL);
xdp_id.ifindex = ifindex;
- xdp_id.flags = flags;
+ xdp_id.flags = xdp_flags;
- ret = libbpf_netlink_send_recv(&req, __dump_link_nlmsg,
+ err = libbpf_netlink_send_recv(&req, __dump_link_nlmsg,
get_xdp_info, &xdp_id);
- if (!ret) {
- size_t sz = min(info_size, sizeof(xdp_id.info));
+ if (err)
+ return libbpf_err(err);
- memcpy(info, &xdp_id.info, sz);
- memset((void *) info + sz, 0, info_size - sz);
- }
+ OPTS_SET(opts, prog_id, xdp_id.info.prog_id);
+ OPTS_SET(opts, drv_prog_id, xdp_id.info.drv_prog_id);
+ OPTS_SET(opts, hw_prog_id, xdp_id.info.hw_prog_id);
+ OPTS_SET(opts, skb_prog_id, xdp_id.info.skb_prog_id);
+ OPTS_SET(opts, attach_mode, xdp_id.info.attach_mode);
- return libbpf_err(ret);
+ return 0;
}
-static __u32 get_xdp_id(struct xdp_link_info *info, __u32 flags)
+int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
+ size_t info_size, __u32 flags)
{
- flags &= XDP_FLAGS_MODES;
+ LIBBPF_OPTS(bpf_xdp_query_opts, opts);
+ size_t sz;
+ int err;
- if (info->attach_mode != XDP_ATTACHED_MULTI && !flags)
- return info->prog_id;
- if (flags & XDP_FLAGS_DRV_MODE)
- return info->drv_prog_id;
- if (flags & XDP_FLAGS_HW_MODE)
- return info->hw_prog_id;
- if (flags & XDP_FLAGS_SKB_MODE)
- return info->skb_prog_id;
+ if (!info_size)
+ return libbpf_err(-EINVAL);
+
+ err = bpf_xdp_query(ifindex, flags, &opts);
+ if (err)
+ return libbpf_err(err);
+
+ /* struct xdp_link_info field layout matches struct bpf_xdp_query_opts
+ * layout after sz field
+ */
+ sz = min(info_size, offsetofend(struct xdp_link_info, attach_mode));
+ memcpy(info, &opts.prog_id, sz);
+ memset((void *)info + sz, 0, info_size - sz);
return 0;
}
-int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags)
+int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id)
{
- struct xdp_link_info info;
+ LIBBPF_OPTS(bpf_xdp_query_opts, opts);
int ret;
- ret = bpf_get_link_xdp_info(ifindex, &info, sizeof(info), flags);
- if (!ret)
- *prog_id = get_xdp_id(&info, flags);
+ ret = bpf_xdp_query(ifindex, flags, &opts);
+ if (ret)
+ return libbpf_err(ret);
- return libbpf_err(ret);
+ flags &= XDP_FLAGS_MODES;
+
+ if (opts.attach_mode != XDP_ATTACHED_MULTI && !flags)
+ *prog_id = opts.prog_id;
+ else if (flags & XDP_FLAGS_DRV_MODE)
+ *prog_id = opts.drv_prog_id;
+ else if (flags & XDP_FLAGS_HW_MODE)
+ *prog_id = opts.hw_prog_id;
+ else if (flags & XDP_FLAGS_SKB_MODE)
+ *prog_id = opts.skb_prog_id;
+ else
+ *prog_id = 0;
+
+ return 0;
+}
+
+
+int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags)
+{
+ return bpf_xdp_query_id(ifindex, flags, prog_id);
}
typedef int (*qdisc_config_t)(struct libbpf_nla_req *req);