rtnetlink: use xarray iterator to implement rtnl_dump_ifinfo()

Adopt net->dev_by_index as I did in commit 0e0939c0ad
("net-procfs: use xarray iterator to implement /proc/net/dev")

This makes sure an existing device is always visible in the dump,
regardless of concurrent insertions/deletions.

v2: added suggestions from Jakub Kicinski and Ido Schimmel,
    thanks for the help !

Link: https://lore.kernel.org/all/20240209142441.6c56435b@kernel.org/
Link: https://lore.kernel.org/all/ZckR-XOsULLI9EHc@shredder/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20240211214404.1882191-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Eric Dumazet 2024-02-11 21:44:04 +00:00 committed by Jakub Kicinski
parent f383ced24d
commit 3e41af9076

View file

@ -2188,25 +2188,22 @@ static int rtnl_valid_dump_ifinfo_req(const struct nlmsghdr *nlh,
static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
{
const struct rtnl_link_ops *kind_ops = NULL;
struct netlink_ext_ack *extack = cb->extack;
const struct nlmsghdr *nlh = cb->nlh;
struct net *net = sock_net(skb->sk);
struct net *tgt_net = net;
int h, s_h;
int idx = 0, s_idx;
struct net_device *dev;
struct hlist_head *head;
struct nlattr *tb[IFLA_MAX+1];
u32 ext_filter_mask = 0;
const struct rtnl_link_ops *kind_ops = NULL;
unsigned int flags = NLM_F_MULTI;
struct nlattr *tb[IFLA_MAX+1];
struct {
unsigned long ifindex;
} *ctx = (void *)cb->ctx;
struct net *tgt_net = net;
u32 ext_filter_mask = 0;
struct net_device *dev;
int master_idx = 0;
int netnsid = -1;
int err, i;
s_h = cb->args[0];
s_idx = cb->args[1];
err = rtnl_valid_dump_ifinfo_req(nlh, cb->strict_check, tb, extack);
if (err < 0) {
if (cb->strict_check)
@ -2250,36 +2247,21 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
flags |= NLM_F_DUMP_FILTERED;
walk_entries:
for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
idx = 0;
head = &tgt_net->dev_index_head[h];
hlist_for_each_entry(dev, head, index_hlist) {
if (link_dump_filtered(dev, master_idx, kind_ops))
goto cont;
if (idx < s_idx)
goto cont;
err = rtnl_fill_ifinfo(skb, dev, net,
RTM_NEWLINK,
NETLINK_CB(cb->skb).portid,
nlh->nlmsg_seq, 0, flags,
ext_filter_mask, 0, NULL, 0,
netnsid, GFP_KERNEL);
if (err < 0) {
if (likely(skb->len))
goto out;
goto out_err;
}
cont:
idx++;
err = 0;
for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
if (link_dump_filtered(dev, master_idx, kind_ops))
continue;
err = rtnl_fill_ifinfo(skb, dev, net, RTM_NEWLINK,
NETLINK_CB(cb->skb).portid,
nlh->nlmsg_seq, 0, flags,
ext_filter_mask, 0, NULL, 0,
netnsid, GFP_KERNEL);
if (err < 0) {
if (likely(skb->len))
err = skb->len;
break;
}
}
out:
err = skb->len;
out_err:
cb->args[1] = idx;
cb->args[0] = h;
cb->seq = tgt_net->dev_base_seq;
nl_dump_check_consistent(cb, nlmsg_hdr(skb));
if (netnsid >= 0)