From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi1-f195.google.com ([209.85.167.195]:38515 "EHLO mail-oi1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726543AbfAMOu4 (ORCPT ); Sun, 13 Jan 2019 09:50:56 -0500 Received: by mail-oi1-f195.google.com with SMTP id a77so15916835oii.5 for ; Sun, 13 Jan 2019 06:50:54 -0800 (PST) MIME-Version: 1.0 References: <20181216101858.9585-2-starnight@g.ncu.edu.tw> In-Reply-To: From: Jian-Hong Pan Date: Sun, 13 Jan 2019 22:51:01 +0800 Message-ID: Subject: Re: [PATCH v5 1/6] net: lorawan: Add LoRaWAN socket module Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-wpan-owner@vger.kernel.org List-ID: To: =?UTF-8?Q?Andreas_F=C3=A4rber?= Cc: "David S . Miller" , Alan Cox , linux-lpwan@lists.infradead.org, netdev@vger.kernel.org, ", "linux-kernel@vger.kernel.org>," , Marcel Holtmann , Dollar Chen , Ken Yu , linux-wpan - ML , Ben Whitten Jian-Hong Pan =E6=96=BC 2019=E5=B9=B41=E6=9C=887= =E6=97=A5 =E9=80=B1=E4=B8=80 =E4=B8=8B=E5=8D=8810:47=E5=AF=AB=E9=81=93=EF= =BC=9A > > Andreas F=C3=A4rber =E6=96=BC 2018=E5=B9=B412=E6=9C=88= 29=E6=97=A5 =E9=80=B1=E5=85=AD =E4=B8=8B=E5=8D=883:27=E5=AF=AB=E9=81=93=EF= =BC=9A > > > > Hi Jian-Hong, > > > > Am 16.12.18 um 11:18 schrieb Jian-Hong Pan: > > > This patch adds a new address/protocol family for LoRaWAN network. > > > It also implements the the functions and maps to Datagram socket for > > > LoRaWAN unconfirmed data messages. > > > > > > Signed-off-by: Jian-Hong Pan > > [...] > > > include/linux/lora/lorawan_netdev.h | 52 +++ > > > net/lorawan/Kconfig | 10 + > > > net/lorawan/Makefile | 2 + > > > net/lorawan/socket.c | 686 ++++++++++++++++++++++++++= ++ > > > 4 files changed, 750 insertions(+) > > > create mode 100644 include/linux/lora/lorawan_netdev.h > > > create mode 100644 net/lorawan/Kconfig > > > create mode 100644 net/lorawan/Makefile > > > create mode 100644 net/lorawan/socket.c > > > > I'm not 100% happy with this yet, but to decouple it from the soft-MAC > > discussion (patches 2-6/6) and to allow reuse by Ben, I've staged it in > > linux-lora.git. > > > > We can clean it up with incremental patches there (and squash later). > > > > > > > > diff --git a/include/linux/lora/lorawan_netdev.h b/include/linux/lora= /lorawan_netdev.h > > > new file mode 100644 > > > index 000000000000..5bffb5164f95 > > > --- /dev/null > > > +++ b/include/linux/lora/lorawan_netdev.h > > > @@ -0,0 +1,52 @@ > > > +/* SPDX-License-Identifier: GPL-2.0-or-later OR BSD-3-Clause */ > > > > Is there any practical reason you dual-license your code? My LoRa code > > is only GPL - should I reconsider that? > > I use dual-license due to the event "[Ksummit-discuss] [CORE TOPIC] > GPL defense issues" > https://lists.linuxfoundation.org/pipermail/ksummit-discuss/2016-August/0= 03580.html > > > > +/*- > > > > I assume the dash is a typo? > > > > > + * LoRaWAN stack related definitions > > > + * > > > + * Copyright (c) 2018 Jian-Hong, Pan > > > + * > > > > Leftover white line from old license header? > > > > > + */ > > > + > > > +#ifndef __LORAWAN_NET_DEVICE_H__ > > > +#define __LORAWAN_NET_DEVICE_H__ > > > + > > > +enum { > > > + LRW_ADDR_APPEUI, > > > + LRW_ADDR_DEVEUI, > > > + LRW_ADDR_DEVADDR, > > > +}; > > > + > > > +struct lrw_addr_in { > > > + int addr_type; > > > + union { > > > + u64 app_eui; > > > + u64 dev_eui; > > > > In my RFC and in linux-lora.git I have a lora_eui typedef - any reason > > you're not using it here? > > lora_eui is defined as a type of u8 array with 8 bytes in > include/linux/lora/dev.h > typedef u8 lora_eui[8]; > It is not a basic nor simple data type. > > 1. There is the endian issue. LoRaWAN uses little endian for > transmission. If u64 data type is used, we can call functions like > cpu_to_le64 and le64_to_cpu to deal the endian jobs directly. > 2. We can compare the EUIs with relational operators directly if the > EUI is not a type of array. > > > > + u32 devaddr; > > > + }; > > > +}; > > > + > > > +struct sockaddr_lorawan { > > > + sa_family_t family; /* AF_LORAWAN */ > > > + struct lrw_addr_in addr_in; > > > +}; > > > + > > > +/** > > > + * lrw_mac_cb - This structure holds the control buffer (cb) of sk_b= uff > > > + * > > > + * @devaddr: the LoRaWAN device address of this LoRaWAN hardware > > > + */ > > > +struct lrw_mac_cb { > > > + u32 devaddr; > > > +}; > > > + > > > +/** > > > + * lrw_get_mac_cb - Get the LoRaWAN MAC control buffer of the sk_buf= f > > > + * @skb: the exchanging sk_buff > > > + * > > > + * Return: the pointer of LoRaWAN MAC control buffer > > > + */ > > > +static inline struct lrw_mac_cb *lrw_get_mac_cb(struct sk_buff *skb) > > > +{ > > > + return (struct lrw_mac_cb *)skb->cb; > > > +} > > > > For LoRa I have a separate lora/skb.h - suggest to split this off into > > its own header consistently. > > Sounds good. > Do you prefer separate them into lora/skb.h or lora/lorawan_skb.h? > > > > + > > > +#endif > > > diff --git a/net/lorawan/Kconfig b/net/lorawan/Kconfig > > > new file mode 100644 > > > index 000000000000..bf6c9b77573b > > > --- /dev/null > > > +++ b/net/lorawan/Kconfig > > > @@ -0,0 +1,10 @@ > > > +config LORAWAN > > > + tristate "LoRaWAN Network support" > > > > The N in LoRaWAN is already for Network. :) > > > > > + help > > > + LoRaWAN defines low data rate, low power and long range wirel= ess > > > + wide area networks. It was designed to organize networks of a= utomation > > > + devices, such as sensors, switches and actuators. It can oper= ate > > > + multiple kilometers wide. > > > > The missing information here to distinguish it from LoRa would be that > > it's a client/server technology centered around gateways. In particular > > gateways that anyone can run, distinguishing it from (Sigfox or) NB-IoT= . > > > > > + > > > + Say Y here to compile LoRaWAN support into the kernel or say = M to > > > + compile it as a module. > > > diff --git a/net/lorawan/Makefile b/net/lorawan/Makefile > > > new file mode 100644 > > > index 000000000000..8c923ca6541a > > > --- /dev/null > > > +++ b/net/lorawan/Makefile > > > @@ -0,0 +1,2 @@ > > > +obj-$(CONFIG_LORAWAN) +=3D lorawan.o > > > +lorawan-objs :=3D socket.o > > > > Both Kconfig and Makefile are not integrated into net/ here. That > > happens only in 6/6. > > > > > diff --git a/net/lorawan/socket.c b/net/lorawan/socket.c > > > new file mode 100644 > > > index 000000000000..7ef106b877ca > > > --- /dev/null > > > +++ b/net/lorawan/socket.c > > > @@ -0,0 +1,686 @@ > > > +// SPDX-License-Identifier: GPL-2.0-or-later OR BSD-3-Clause > > > +/*- > > > > ? > > > > > + * LoRaWAN stack related definitions > > > + * > > > + * Copyright (c) 2018 Jian-Hong, Pan > > > + * > > > > ? > > > > > + */ > > > + > > > +#define LORAWAN_MODULE_NAME "lorawan" > > > + > > > +#define pr_fmt(fmt) LORAWAN_MODULE_NAME ": " fmt > > > + > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include /* For TIOCOUTQ/INQ */ > > > +#include > > > +#include > > > > Please sort headers alphabetically. > > > > > + > > > +/** > > > + * dgram_sock - This structure holds the states of Datagram socket > > > + * > > > + * @sk: network layer representation of the soc= ket > > > + * sk must be the first member of dgram_sock > > > > Might that sentence be more useful as inline comment below? > > > > > + * @src_devaddr: the LoRaWAN device address for this connection > > > + * @bound: this socket is bound or not > > > + * @connected: this socket is connected to the destina= tion or not > > > + * @want_ack: this socket needs to ack for the connec= tion or not > > > > Doesn't exist below? > > > > > + */ > > > +struct dgram_sock { > > > + struct sock sk; > > > + u32 src_devaddr; > > > + > > > + u8 bound:1; > > > + u8 connected:1; > > > +}; > > > + > > > +static HLIST_HEAD(dgram_head); > > > +static DEFINE_RWLOCK(dgram_lock); > > > + > > > +static struct dgram_sock * > > > +dgram_sk(const struct sock *sk) > > > +{ > > > + return container_of(sk, struct dgram_sock, sk); > > > +} > > > + > > > +static struct net_device * > > > +lrw_get_dev_by_addr(struct net *net, u32 devaddr) > > > +{ > > > + __be32 be_addr =3D cpu_to_be32(devaddr); > > > + struct net_device *ndev =3D NULL; > > > + > > > + rcu_read_lock(); > > > + ndev =3D dev_getbyhwaddr_rcu(net, ARPHRD_LORAWAN, (char *)&be_a= ddr); > > > + if (ndev) > > > + dev_hold(ndev); > > > + rcu_read_unlock(); > > > + > > > + return ndev; > > > +} > > > + > > > +static int > > > +dgram_init(struct sock *sk) > > > +{ > > > + return 0; > > > +} > > > + > > > +static void > > > +dgram_close(struct sock *sk, long timeout) > > > +{ > > > + sk_common_release(sk); > > > +} > > > + > > > +static int > > > +dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len) > > > +{ > > > + struct sockaddr_lorawan *addr =3D (struct sockaddr_lorawan *)ua= ddr; > > > + struct dgram_sock *ro =3D dgram_sk(sk); > > > + struct net_device *ndev; > > > + int ret; > > > + > > > + lock_sock(sk); > > > + ro->bound =3D 0; > > > + > > > + ret =3D -EINVAL; > > > + if (len < sizeof(*addr)) > > > + goto dgram_bind_end; > > > + > > > + if (addr->family !=3D AF_LORAWAN) > > > + goto dgram_bind_end; > > > + > > > + if (addr->addr_in.addr_type !=3D LRW_ADDR_DEVADDR) > > > + goto dgram_bind_end; > > > + > > > + pr_debug("%s: bind address %X\n", __func__, addr->addr_in.devad= dr); > > > + ndev =3D lrw_get_dev_by_addr(sock_net(sk), addr->addr_in.devadd= r); > > > + if (!ndev) { > > > + ret =3D -ENODEV; > > > + goto dgram_bind_end; > > > + } > > > + netdev_dbg(ndev, "%s: get ndev\n", __func__); > > > + > > > + if (ndev->type !=3D ARPHRD_LORAWAN) { > > > + ret =3D -ENODEV; > > > + goto dgram_bind_end; > > > > This is leaking ndev. > > > > > + } > > > + > > > + ro->src_devaddr =3D addr->addr_in.devaddr; > > > + ro->bound =3D 1; > > > + ret =3D 0; > > > + dev_put(ndev); > > > + pr_debug("%s: bound address %X\n", __func__, ro->src_devaddr); > > > + > > > +dgram_bind_end: > > > + release_sock(sk); > > > + return ret; > > > +} > > > + > > > +static int > > > +lrw_dev_hard_header(struct sk_buff *skb, struct net_device *ndev, > > > + const u32 src_devaddr, size_t len) > > > +{ > > > + /* TODO: Prepare the LoRaWAN sending header here */ > > > > I wonder, is your idea that you would always write headers here but hav= e > > me ignore them in hard-MAC drivers by accessing data and not head? > > > > I.e., does this dgram (and a later seqpacket) implementation give us no= t > > just the buffer to pass to hard-MAC or soft-MAC but actually LoRa, too, > > so that maclorawan needs to further post-processing of header/checksum? > > I put lrw_dev_hard_header function here for the header processing nnd > thought it might be called in the future originally. However, as you > mentioned, we already have soft and hard-MAC and this abstraction > layer only pass the buffer. So, it can be removed now. > > > > + return 0; > > > +} > > > + > > > +static int > > > +dgram_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) > > > +{ > > > + struct dgram_sock *ro =3D dgram_sk(sk); > > > + struct net_device *ndev; > > > + struct sk_buff *skb; > > > + size_t hlen; > > > + size_t tlen; > > > + int ret; > > > + > > > + pr_debug("%s: going to send %zu bytes", __func__, size); > > > > \n > > > > > + if (msg->msg_flags & MSG_OOB) { > > > + pr_debug("msg->msg_flags =3D 0x%x\n", msg->msg_flags); > > > + return -EOPNOTSUPP; > > > + } > > > + > > > + pr_debug("%s: check msg_name\n", __func__); > > > + if (!ro->connected && !msg->msg_name) > > > + return -EDESTADDRREQ; > > > + else if (ro->connected && msg->msg_name) > > > + return -EISCONN; > > > + > > > + pr_debug("%s: check bound\n", __func__); > > > + if (!ro->bound) > > > + ndev =3D dev_getfirstbyhwtype(sock_net(sk), ARPHRD_LORA= WAN); > > > + else > > > + ndev =3D lrw_get_dev_by_addr(sock_net(sk), ro->src_deva= ddr); > > > + > > > + if (!ndev) { > > > + pr_debug("no dev\n"); > > > + ret =3D -ENXIO; > > > + goto dgram_sendmsg_end; > > > + } > > > + > > > + if (size > ndev->mtu) { > > > + netdev_dbg(ndev, "size =3D %zu, mtu =3D %u\n", size, nd= ev->mtu); > > > + ret =3D -EMSGSIZE; > > > + goto dgram_sendmsg_end; > > > > Leaks at least ndev from lrw_get_dev_by_addr. > > > > > + } > > > + > > > + netdev_dbg(ndev, "%s: create skb\n", __func__); > > > + hlen =3D LL_RESERVED_SPACE(ndev); > > > + tlen =3D ndev->needed_tailroom; > > > + skb =3D sock_alloc_send_skb(sk, hlen + tlen + size, > > > + msg->msg_flags & MSG_DONTWAIT, > > > + &ret); > > > + > > > + if (!skb) > > > + goto dgram_sendmsg_no_skb; > > > + > > > + skb_reserve(skb, hlen); > > > + skb_reset_network_header(skb); > > > + > > > + ret =3D lrw_dev_hard_header(skb, ndev, 0, size); > > > + if (ret < 0) > > > + goto dgram_sendmsg_no_skb; > > > + > > > + ret =3D memcpy_from_msg(skb_put(skb, size), msg, size); > > > + if (ret > 0) > > > + goto dgram_sendmsg_err_skb; > > > + > > > + skb->dev =3D ndev; > > > + skb->protocol =3D htons(ETH_P_LORAWAN); > > > + > > > + netdev_dbg(ndev, "%s: push skb to xmit queue\n", __func__); > > > + ret =3D dev_queue_xmit(skb); > > > + if (ret > 0) > > > + ret =3D net_xmit_errno(ret); > > > + netdev_dbg(ndev, "%s: pushed skb to xmit queue with ret=3D%d\n"= , > > > + __func__, ret); > > > + dev_put(ndev); > > > + > > > + return ret ?: size; > > > + > > > +dgram_sendmsg_err_skb: > > > + kfree_skb(skb); > > > +dgram_sendmsg_no_skb: > > > + dev_put(ndev); > > > + > > > +dgram_sendmsg_end: > > > + return ret; > > > +} > > > + > > > +static int > > > +dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, > > > + int noblock, int flags, int *addr_len) > > > +{ > > > + DECLARE_SOCKADDR(struct sockaddr_lorawan *, saddr, msg->msg_nam= e); > > > + struct sk_buff *skb; > > > + size_t copied =3D 0; > > > + int err; > > > + > > > + skb =3D skb_recv_datagram(sk, flags, noblock, &err); > > > + if (!skb) > > > + goto dgram_recvmsg_end; > > > + > > > + copied =3D skb->len; > > > + if (len < copied) { > > > + msg->msg_flags |=3D MSG_TRUNC; > > > + copied =3D len; > > > + } > > > + > > > + err =3D skb_copy_datagram_msg(skb, 0, msg, copied); > > > + if (err) > > > + goto dgram_recvmsg_done; > > > + > > > + sock_recv_ts_and_drops(msg, sk, skb); > > > + if (saddr) { > > > + memset(saddr, 0, sizeof(*saddr)); > > > + saddr->family =3D AF_LORAWAN; > > > + saddr->addr_in.devaddr =3D lrw_get_mac_cb(skb)->devaddr= ; > > > + *addr_len =3D sizeof(*saddr); > > > + } > > > + > > > + if (flags & MSG_TRUNC) > > > + copied =3D skb->len; > > > + > > > +dgram_recvmsg_done: > > > + skb_free_datagram(sk, skb); > > > + > > > +dgram_recvmsg_end: > > > + if (err) > > > + return err; > > > + return copied; > > > +} > > > + > > > +static int > > > +dgram_hash(struct sock *sk) > > > +{ > > > + pr_debug("%s\n", __func__); > > > + write_lock_bh(&dgram_lock); > > > + sk_add_node(sk, &dgram_head); > > > + sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); > > > + write_unlock_bh(&dgram_lock); > > > + > > > + return 0; > > > +} > > > + > > > +static void > > > +dgram_unhash(struct sock *sk) > > > +{ > > > + pr_debug("%s\n", __func__); > > > + write_lock_bh(&dgram_lock); > > > + if (sk_del_node_init(sk)) > > > + sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); > > > + write_unlock_bh(&dgram_lock); > > > +} > > > + > > > +static int > > > +dgram_connect(struct sock *sk, struct sockaddr *uaddr, int len) > > > +{ > > > + struct dgram_sock *ro =3D dgram_sk(sk); > > > + > > > + /* Nodes of LoRaWAN send data to a gateway only, then data is r= eceived > > > + * and transferred to servers with the gateway's policy. > > > + * So, the destination address is not used by nodes. > > > + */ > > > + lock_sock(sk); > > > + ro->connected =3D 1; > > > + release_sock(sk); > > > + > > > + return 0; > > > +} > > > + > > > +static int > > > +dgram_disconnect(struct sock *sk, int flags) > > > +{ > > > + struct dgram_sock *ro =3D dgram_sk(sk); > > > + > > > + lock_sock(sk); > > > + ro->connected =3D 0; > > > + release_sock(sk); > > > + > > > + return 0; > > > +} > > > + > > > +static int > > > +dgram_ioctl(struct sock *sk, int cmd, unsigned long arg) > > > +{ > > > + struct net_device *ndev =3D sk->sk_dst_cache->dev; > > > + struct sk_buff *skb; > > > + int amount; > > > + int err; > > > + > > > + netdev_dbg(ndev, "%s: ioctl file (cmd=3D0x%X)\n", __func__, cmd= ); > > > + switch (cmd) { > > > + case SIOCOUTQ: > > > + amount =3D sk_wmem_alloc_get(sk); > > > + err =3D put_user(amount, (int __user *)arg); > > > + break; > > > + case SIOCINQ: > > > + amount =3D 0; > > > + spin_lock_bh(&sk->sk_receive_queue.lock); > > > + skb =3D skb_peek(&sk->sk_receive_queue); > > > + if (skb) { > > > + /* We will only return the amount of this packe= t > > > + * since that is all that will be read. > > > + */ > > > + amount =3D skb->len; > > > + } > > > + spin_unlock_bh(&sk->sk_receive_queue.lock); > > > + err =3D put_user(amount, (int __user *)arg); > > > + break; > > > + default: > > > + err =3D -ENOIOCTLCMD; > > > + } > > > + > > > + return err; > > > +} > > > + > > > +static int > > > +dgram_getsockopt(struct sock *sk, int level, int optname, > > > + char __user *optval, int __user *optlen) > > > +{ > > > + int val, len; > > > + > > > + if (level !=3D SOL_LORAWAN) > > > + return -EOPNOTSUPP; > > > + > > > + if (get_user(len, optlen)) > > > + return -EFAULT; > > > + > > > + len =3D min_t(unsigned int, len, sizeof(int)); > > > + > > > + switch (optname) { > > > + default: > > > + return -ENOPROTOOPT; > > > + } > > > + > > > + if (put_user(len, optlen)) > > > + return -EFAULT; > > > + > > > + if (copy_to_user(optval, &val, len)) > > > + return -EFAULT; > > > + > > > + return 0; > > > +} > > > + > > > +static int > > > +dgram_setsockopt(struct sock *sk, int level, int optname, > > > + char __user *optval, unsigned int optlen) > > > +{ > > > + int val; > > > + int err; > > > + > > > + err =3D 0; > > > + > > > + if (optlen < sizeof(int)) > > > + return -EINVAL; > > > + > > > + if (get_user(val, (int __user *)optval)) > > > + return -EFAULT; > > > + > > > + lock_sock(sk); > > > + > > > + switch (optname) { > > > + default: > > > + err =3D -ENOPROTOOPT; > > > + break; > > > + } > > > + > > > + release_sock(sk); > > > + > > > + return err; > > > +} > > > + > > > +static struct proto lrw_dgram_prot =3D { > > > + .name =3D "LoRaWAN", > > > + .owner =3D THIS_MODULE, > > > + .obj_size =3D sizeof(struct dgram_sock), > > > + .init =3D dgram_init, > > > + .close =3D dgram_close, > > > + .bind =3D dgram_bind, > > > + .sendmsg =3D dgram_sendmsg, > > > + .recvmsg =3D dgram_recvmsg, > > > + .hash =3D dgram_hash, > > > + .unhash =3D dgram_unhash, > > > + .connect =3D dgram_connect, > > > + .disconnect =3D dgram_disconnect, > > > + .ioctl =3D dgram_ioctl, > > > + .getsockopt =3D dgram_getsockopt, > > > + .setsockopt =3D dgram_setsockopt, > > > +}; > > > + > > > +static int > > > +lrw_sock_release(struct socket *sock) > > > +{ > > > + struct sock *sk =3D sock->sk; > > > + > > > + if (sk) { > > > + sock->sk =3D NULL; > > > + sk->sk_prot->close(sk, 0); > > > + } > > > + > > > + return 0; > > > +} > > > + > > > +static int > > > +lrw_sock_bind(struct socket *sock, struct sockaddr *uaddr, int addr_= len) > > > +{ > > > + struct sockaddr_lorawan *addr =3D (struct sockaddr_lorawan *)ua= ddr; > > > + struct sock *sk =3D sock->sk; > > > + > > > + pr_debug("%s: bind address %X\n", __func__, addr->addr_in.devad= dr); > > > + if (sk->sk_prot->bind) > > > + return sk->sk_prot->bind(sk, uaddr, addr_len); > > > + > > > + return sock_no_bind(sock, uaddr, addr_len); > > > +} > > > + > > > +static int > > > +lrw_sock_connect(struct socket *sock, struct sockaddr *uaddr, > > > + int addr_len, int flags) > > > +{ > > > + struct sock *sk =3D sock->sk; > > > + > > > + if (addr_len < sizeof(uaddr->sa_family)) > > > + return -EINVAL; > > > + > > > + return sk->sk_prot->connect(sk, uaddr, addr_len); > > > +} > > > + > > > +static int > > > +lrw_ndev_ioctl(struct sock *sk, struct ifreq __user *arg, unsigned i= nt cmd) > > > +{ > > > + struct net_device *ndev; > > > + struct ifreq ifr; > > > + int ret; > > > + > > > + pr_debug("%s: cmd %ud\n", __func__, cmd); > > > + ret =3D -ENOIOCTLCMD; > > > + > > > + if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) > > > + return -EFAULT; > > > + > > > + ifr.ifr_name[IFNAMSIZ - 1] =3D 0; > > > + > > > + dev_load(sock_net(sk), ifr.ifr_name); > > > + ndev =3D dev_get_by_name(sock_net(sk), ifr.ifr_name); > > > + > > > + netdev_dbg(ndev, "%s: cmd %ud\n", __func__, cmd); > > > + if (!ndev) > > > + return -ENODEV; > > > + > > > + if (ndev->type =3D=3D ARPHRD_LORAWAN && ndev->netdev_ops->ndo_d= o_ioctl) > > > + ret =3D ndev->netdev_ops->ndo_do_ioctl(ndev, &ifr, cmd)= ; > > > + > > > + if (!ret && copy_to_user(arg, &ifr, sizeof(struct ifreq))) > > > + ret =3D -EFAULT; > > > + dev_put(ndev); > > > + > > > + return ret; > > > +} > > > + > > > +static int > > > +lrw_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long = arg) > > > +{ > > > + struct sock *sk =3D sock->sk; > > > + > > > + pr_debug("%s: cmd %ud\n", __func__, cmd); > > > + switch (cmd) { > > > + case SIOCGSTAMP: > > > + return sock_get_timestamp(sk, (struct timeval __user *)= arg); > > > + case SIOCGSTAMPNS: > > > + return sock_get_timestampns(sk, (struct timespec __user= *)arg); > > > + case SIOCOUTQ: > > > + case SIOCINQ: > > > + if (!sk->sk_prot->ioctl) > > > + return -ENOIOCTLCMD; > > > + return sk->sk_prot->ioctl(sk, cmd, arg); > > > + default: > > > + return lrw_ndev_ioctl(sk, (struct ifreq __user *)arg, c= md); > > > + } > > > +} > > > + > > > +static int > > > +lrw_sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t len= ) > > > +{ > > > + struct sock *sk =3D sock->sk; > > > + > > > + pr_debug("%s: going to send %zu bytes\n", __func__, len); > > > + return sk->sk_prot->sendmsg(sk, msg, len); > > > +} > > > + > > > +static const struct proto_ops lrw_dgram_ops =3D { > > > + .family =3D PF_LORAWAN, > > > + .owner =3D THIS_MODULE, > > > + .release =3D lrw_sock_release, > > > + .bind =3D lrw_sock_bind, > > > + .connect =3D lrw_sock_connect, > > > + .socketpair =3D sock_no_socketpair, > > > + .accept =3D sock_no_accept, > > > + .getname =3D sock_no_getname, > > > + .poll =3D datagram_poll, > > > + .ioctl =3D lrw_sock_ioctl, > > > + .listen =3D sock_no_listen, > > > + .shutdown =3D sock_no_shutdown, > > > + .setsockopt =3D sock_common_setsockopt, > > > + .getsockopt =3D sock_common_getsockopt, > > > + .sendmsg =3D lrw_sock_sendmsg, > > > + .recvmsg =3D sock_common_recvmsg, > > > + .mmap =3D sock_no_mmap, > > > + .sendpage =3D sock_no_sendpage, > > > +}; > > > + > > > +static int > > > +lorawan_creat(struct net *net, struct socket *sock, int protocol, in= t kern) > > > > create > > Also, why lorawan_ here and lrw_ elsewhere? > > > > > +{ > > > + struct sock *sk; > > > + int ret; > > > + > > > + if (!net_eq(net, &init_net)) > > > + return -EAFNOSUPPORT; > > > + > > > + if (sock->type !=3D SOCK_DGRAM) > > > + return -EAFNOSUPPORT; > > > + > > > + /* Allocates enough memory for dgram_sock whose first member is= sk */ > > > + sk =3D sk_alloc(net, PF_LORAWAN, GFP_KERNEL, &lrw_dgram_prot, k= ern); > > > + if (!sk) > > > + return -ENOMEM; > > > + > > > + sock->ops =3D &lrw_dgram_ops; > > > + sock_init_data(sock, sk); > > > + sk->sk_family =3D PF_LORAWAN; > > > + sock_set_flag(sk, SOCK_ZAPPED); > > > + > > > + if (sk->sk_prot->hash) { > > > + ret =3D sk->sk_prot->hash(sk); > > > + if (ret) { > > > + sk_common_release(sk); > > > + goto lorawan_creat_end; > > > + } > > > + } > > > + > > > + if (sk->sk_prot->init) { > > > + ret =3D sk->sk_prot->init(sk); > > > + if (ret) > > > + sk_common_release(sk); > > > + } > > > + > > > +lorawan_creat_end: > > > > create > > > > > + return ret; > > > +} > > > + > > > +static const struct net_proto_family lorawan_family_ops =3D { > > > + .owner =3D THIS_MODULE, > > > + .family =3D PF_LORAWAN, > > > + .create =3D lorawan_creat, > > > +}; > > > + > > > +static int > > > +lrw_dgram_deliver(struct net_device *ndev, struct sk_buff *skb) > > > +{ > > > + struct dgram_sock *ro; > > > + struct sock *sk; > > > + bool found; > > > + int ret; > > > + > > > + ret =3D NET_RX_SUCCESS; > > > + found =3D false; > > > > In times of C99 you could probably fold that into the declarations. I have thought this issue many times, but give up and just follow "Reverse XMAS tree declarations" rule in net subsystem. [1] David also gave the related review comment. [2] [1] https://lore.kernel.org/patchwork/patch/732076/ [2] https://lkml.org/lkml/2018/11/5/916 Regards, Jian-Hong Pan > > > + > > > + read_lock(&dgram_lock); > > > + sk_for_each(sk, &dgram_head) { > > > + ro =3D dgram_sk(sk); > > > + if (cpu_to_be32(ro->src_devaddr) =3D=3D *(__be32 *)ndev= ->dev_addr) { > > > + found =3D true; > > > + break; > > > + } > > > + } > > > + read_unlock(&dgram_lock); > > > + > > > + if (!found) > > > + goto lrw_dgram_deliver_err; > > > + > > > + skb =3D skb_share_check(skb, GFP_ATOMIC); > > > + if (!skb) > > > + return NET_RX_DROP; > > > + > > > + if (sock_queue_rcv_skb(sk, skb) < 0) > > > + goto lrw_dgram_deliver_err; > > > + > > > + return ret; > > > + > > > +lrw_dgram_deliver_err: > > > + kfree_skb(skb); > > > + ret =3D NET_RX_DROP; > > > + return ret; > > > +} > > > + > > > +static int > > > +lorawan_rcv(struct sk_buff *skb, struct net_device *ndev, > > > + struct packet_type *pt, struct net_device *orig_ndev) > > > +{ > > > + if (!netif_running(ndev)) > > > + goto lorawan_rcv_drop; > > > + > > > + if (!net_eq(dev_net(ndev), &init_net)) > > > + goto lorawan_rcv_drop; > > > + > > > + if (ndev->type !=3D ARPHRD_LORAWAN) > > > + goto lorawan_rcv_drop; > > > + > > > + if (skb->pkt_type !=3D PACKET_OTHERHOST) > > > + return lrw_dgram_deliver(ndev, skb); > > > + > > > +lorawan_rcv_drop: > > > + kfree_skb(skb); > > > + return NET_RX_DROP; > > > +} > > > + > > > +static struct packet_type lorawan_packet_type =3D { > > > + .type =3D htons(ETH_P_LORAWAN), > > > + .func =3D lorawan_rcv, > > > +}; > > > + > > > +static int __init > > > +lrw_sock_init(void) > > > +{ > > > + int ret; > > > + > > > + pr_info("module inserted\n"); > > > + ret =3D proto_register(&lrw_dgram_prot, 1); > > > + if (ret) > > > + goto lrw_sock_init_end; > > > + > > > + /* Tell SOCKET that we are alive */ > > > > Drop? > > > > > + ret =3D sock_register(&lorawan_family_ops); > > > + if (ret) > > > + goto lrw_sock_init_err; > > > + > > > + dev_add_pack(&lorawan_packet_type); > > > + ret =3D 0; > > > + goto lrw_sock_init_end; > > > + > > > +lrw_sock_init_err: > > > + proto_unregister(&lrw_dgram_prot); > > > + > > > +lrw_sock_init_end: > > > + return 0; > > > > return ret;? > > > > > +} > > > + > > > +static void __exit > > > +lrw_sock_exit(void) > > > +{ > > > + dev_remove_pack(&lorawan_packet_type); > > > + sock_unregister(PF_LORAWAN); > > > + proto_unregister(&lrw_dgram_prot); > > > + pr_info("module removed\n"); > > > +} > > > + > > > +module_init(lrw_sock_init); > > > +module_exit(lrw_sock_exit); > > > + > > > +MODULE_AUTHOR("Jian-Hong Pan, "); > > > > Drop the comma? > > > > > +MODULE_DESCRIPTION("LoRaWAN socket kernel module"); > > > > Aren't they all kernel modules? :) > > > > > +MODULE_LICENSE("Dual BSD/GPL"); > > > +MODULE_ALIAS_NETPROTO(PF_LORAWAN); > > Thanks for the reviewing. Preparing the fixing patches now. :) > > Jain-Hong Pan