diff options
author | Tanner Love <tannerlove@google.com> | 2020-11-06 21:07:40 +0300 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2020-11-10 03:41:40 +0300 |
commit | 9c661b0b85444e426d3f23250305eeb16f6ffe88 (patch) | |
tree | ccd38de01ae8ce6c1ca2ff0c2d5b14eb10ae73ad /net/packet/af_packet.c | |
parent | a3ce2b109a59ee9670706ae8126dcc04cfe261cd (diff) | |
download | linux-9c661b0b85444e426d3f23250305eeb16f6ffe88.tar.xz |
net/packet: make packet_fanout.arr size configurable up to 64K
One use case of PACKET_FANOUT is lockless reception with one socket
per CPU. 256 is a practical limit on increasingly many machines.
Increase PACKET_FANOUT_MAX to 64K. Expand setsockopt PACKET_FANOUT to
take an extra argument max_num_members. Also explicitly define a
fanout_args struct, instead of implicitly casting to an integer. This
documents the API and simplifies the control flow.
If max_num_members is not specified or is set to 0, then 256 is used,
same as before.
Signed-off-by: Tanner Love <tannerlove@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/packet/af_packet.c')
-rw-r--r-- | net/packet/af_packet.c | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index cefbd50c1090..62ebfaa7adcb 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1636,13 +1636,15 @@ static bool fanout_find_new_id(struct sock *sk, u16 *new_id) return false; } -static int fanout_add(struct sock *sk, u16 id, u16 type_flags) +static int fanout_add(struct sock *sk, struct fanout_args *args) { struct packet_rollover *rollover = NULL; struct packet_sock *po = pkt_sk(sk); + u16 type_flags = args->type_flags; struct packet_fanout *f, *match; u8 type = type_flags & 0xff; u8 flags = type_flags >> 8; + u16 id = args->id; int err; switch (type) { @@ -1700,11 +1702,21 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) } } err = -EINVAL; - if (match && match->flags != flags) - goto out; - if (!match) { + if (match) { + if (match->flags != flags) + goto out; + if (args->max_num_members && + args->max_num_members != match->max_num_members) + goto out; + } else { + if (args->max_num_members > PACKET_FANOUT_MAX) + goto out; + if (!args->max_num_members) + /* legacy PACKET_FANOUT_MAX */ + args->max_num_members = 256; err = -ENOMEM; - match = kzalloc(sizeof(*match), GFP_KERNEL); + match = kvzalloc(struct_size(match, arr, args->max_num_members), + GFP_KERNEL); if (!match) goto out; write_pnet(&match->net, sock_net(sk)); @@ -1720,6 +1732,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) match->prot_hook.func = packet_rcv_fanout; match->prot_hook.af_packet_priv = match; match->prot_hook.id_match = match_fanout_group; + match->max_num_members = args->max_num_members; list_add(&match->list, &fanout_list); } err = -EINVAL; @@ -1730,7 +1743,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) match->prot_hook.type == po->prot_hook.type && match->prot_hook.dev == po->prot_hook.dev) { err = -ENOSPC; - if (refcount_read(&match->sk_ref) < PACKET_FANOUT_MAX) { + if (refcount_read(&match->sk_ref) < match->max_num_members) { __dev_remove_pack(&po->prot_hook); po->fanout = match; po->rollover = rollover; @@ -1744,7 +1757,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) if (err && !refcount_read(&match->sk_ref)) { list_del(&match->list); - kfree(match); + kvfree(match); } out: @@ -3075,7 +3088,7 @@ static int packet_release(struct socket *sock) kfree(po->rollover); if (f) { fanout_release_data(f); - kfree(f); + kvfree(f); } /* * Now the socket is dead. No more input will appear. @@ -3866,14 +3879,14 @@ packet_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval, } case PACKET_FANOUT: { - int val; + struct fanout_args args = { 0 }; - if (optlen != sizeof(val)) + if (optlen != sizeof(int) && optlen != sizeof(args)) return -EINVAL; - if (copy_from_sockptr(&val, optval, sizeof(val))) + if (copy_from_sockptr(&args, optval, optlen)) return -EFAULT; - return fanout_add(sk, val & 0xffff, val >> 16); + return fanout_add(sk, &args); } case PACKET_FANOUT_DATA: { |