From e5b42483ccce50d5b957f474fd332afd4ef0c27b Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Fri, 24 Mar 2023 23:11:49 +0100 Subject: dev_ioctl: fix a W=1 warning This fixes the following warning when compiled with GCC 12.2.0 and W=1. net/core/dev_ioctl.c:475: warning: Function parameter or member 'data' not described in 'dev_ioctl' Signed-off-by: Heiner Kallweit Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- net/core/dev_ioctl.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net/core/dev_ioctl.c') diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 5cdbfbf9a7dc..846669426236 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -462,6 +462,7 @@ EXPORT_SYMBOL(dev_load); * @net: the applicable net namespace * @cmd: command to issue * @ifr: pointer to a struct ifreq in user space + * @data: data exchanged with userspace * @need_copyout: whether or not copy_to_user() should be called * * Issue ioctl functions to devices. This is normally called by the -- cgit v1.2.3 From 00d521b39307c3232bdc685c2e9fd82ed973ac24 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sun, 2 Apr 2023 15:37:49 +0300 Subject: net: don't abuse "default" case for unknown ioctl in dev_ifsioc() The "switch (cmd)" block from dev_ifsioc() gained a bit too much unnecessary manual handling of "cmd" in the "default" case, starting with the private ioctls. Clean that up by using the "ellipsis" gcc extension, adding separate cases for the rest of the ioctls, and letting the default case only return -EINVAL. Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/core/dev_ioctl.c | 42 +++++++++++++++++++----------------------- 1 file changed, 19 insertions(+), 23 deletions(-) (limited to 'net/core/dev_ioctl.c') diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 846669426236..1c0256ea522f 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -391,36 +391,32 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr, void __user *data, rtnl_lock(); return err; + case SIOCDEVPRIVATE ... SIOCDEVPRIVATE + 15: + return dev_siocdevprivate(dev, ifr, data, cmd); + case SIOCSHWTSTAMP: err = net_hwtstamp_validate(ifr); if (err) return err; fallthrough; - /* - * Unknown or private ioctl - */ - default: - if (cmd >= SIOCDEVPRIVATE && - cmd <= SIOCDEVPRIVATE + 15) - return dev_siocdevprivate(dev, ifr, data, cmd); - - if (cmd == SIOCGMIIPHY || - cmd == SIOCGMIIREG || - cmd == SIOCSMIIREG || - cmd == SIOCSHWTSTAMP || - cmd == SIOCGHWTSTAMP) { - err = dev_eth_ioctl(dev, ifr, cmd); - } else if (cmd == SIOCBONDENSLAVE || - cmd == SIOCBONDRELEASE || - cmd == SIOCBONDSETHWADDR || - cmd == SIOCBONDSLAVEINFOQUERY || - cmd == SIOCBONDINFOQUERY || - cmd == SIOCBONDCHANGEACTIVE) { - err = dev_siocbond(dev, ifr, cmd); - } else - err = -EINVAL; + case SIOCGHWTSTAMP: + case SIOCGMIIPHY: + case SIOCGMIIREG: + case SIOCSMIIREG: + return dev_eth_ioctl(dev, ifr, cmd); + + case SIOCBONDENSLAVE: + case SIOCBONDRELEASE: + case SIOCBONDSETHWADDR: + case SIOCBONDSLAVEINFOQUERY: + case SIOCBONDINFOQUERY: + case SIOCBONDCHANGEACTIVE: + return dev_siocbond(dev, ifr, cmd); + /* Unknown ioctl */ + default: + err = -EINVAL; } return err; } -- cgit v1.2.3 From 1193db2a55b6b04f296f03affdfa80c16ecc3814 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sun, 2 Apr 2023 15:37:50 +0300 Subject: net: simplify handling of dsa_ndo_eth_ioctl() return code In the expression "x == 0 || x != -95", the term "x == 0" does not change the expression's logical value, because 0 != -95, and so, if x is 0, the expression would still be true by virtue of the second term. If x is non-zero, the expression depends on the truth value of the second term anyway. As such, the first term is redundant and can be deleted. Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/core/dev_ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/dev_ioctl.c') diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 1c0256ea522f..b299fb23fcfa 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -249,7 +249,7 @@ static int dev_eth_ioctl(struct net_device *dev, int err; err = dsa_ndo_eth_ioctl(dev, ifr, cmd); - if (err == 0 || err != -EOPNOTSUPP) + if (err != -EOPNOTSUPP) return err; if (ops->ndo_eth_ioctl) { -- cgit v1.2.3 From 4ee58e1e56800b589afe31c34547e2bc0c59f586 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sun, 2 Apr 2023 15:37:51 +0300 Subject: net: promote SIOCSHWTSTAMP and SIOCGHWTSTAMP ioctls to dedicated handlers DSA does not want to intercept all ioctls handled by dev_eth_ioctl(), only SIOCSHWTSTAMP. This can be seen from commit f685e609a301 ("net: dsa: Deny PTP on master if switch supports it"). However, the way in which the dsa_ndo_eth_ioctl() is called would suggest otherwise. Split the handling of SIOCSHWTSTAMP and SIOCGHWTSTAMP ioctls into separate case statements of dev_ifsioc(), and make each one call its own sub-function. This also removes the dsa_ndo_eth_ioctl() call from dev_eth_ioctl(), which from now on exclusively handles PHY ioctls. Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/core/dev_ioctl.c | 39 ++++++++++++++++++++++++++------------- 1 file changed, 26 insertions(+), 13 deletions(-) (limited to 'net/core/dev_ioctl.c') diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index b299fb23fcfa..3b1402f6897c 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -246,20 +246,34 @@ static int dev_eth_ioctl(struct net_device *dev, struct ifreq *ifr, unsigned int cmd) { const struct net_device_ops *ops = dev->netdev_ops; + + if (!ops->ndo_eth_ioctl) + return -EOPNOTSUPP; + + if (!netif_device_present(dev)) + return -ENODEV; + + return ops->ndo_eth_ioctl(dev, ifr, cmd); +} + +static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr) +{ + return dev_eth_ioctl(dev, ifr, SIOCGHWTSTAMP); +} + +static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) +{ int err; - err = dsa_ndo_eth_ioctl(dev, ifr, cmd); - if (err != -EOPNOTSUPP) + err = net_hwtstamp_validate(ifr); + if (err) return err; - if (ops->ndo_eth_ioctl) { - if (netif_device_present(dev)) - err = ops->ndo_eth_ioctl(dev, ifr, cmd); - else - err = -ENODEV; - } + err = dsa_ndo_eth_ioctl(dev, ifr, SIOCSHWTSTAMP); + if (err != -EOPNOTSUPP) + return err; - return err; + return dev_eth_ioctl(dev, ifr, SIOCSHWTSTAMP); } static int dev_siocbond(struct net_device *dev, @@ -395,12 +409,11 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr, void __user *data, return dev_siocdevprivate(dev, ifr, data, cmd); case SIOCSHWTSTAMP: - err = net_hwtstamp_validate(ifr); - if (err) - return err; - fallthrough; + return dev_set_hwtstamp(dev, ifr); case SIOCGHWTSTAMP: + return dev_get_hwtstamp(dev, ifr); + case SIOCGMIIPHY: case SIOCGMIIREG: case SIOCSMIIREG: -- cgit v1.2.3 From d5d5fd8f2552f6b9c50d3937c77b6783f99fbe83 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sun, 2 Apr 2023 15:37:52 +0300 Subject: net: move copy_from_user() out of net_hwtstamp_validate() The kernel will want to start using the more meaningful struct hwtstamp_config pointer in more places, so move the copy_from_user() at the beginning of dev_set_hwtstamp() in order to get to that, and pass this argument to net_hwtstamp_validate(). Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/core/dev_ioctl.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'net/core/dev_ioctl.c') diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 3b1402f6897c..34a0da5fbcfc 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -183,22 +183,18 @@ static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cm return err; } -static int net_hwtstamp_validate(struct ifreq *ifr) +static int net_hwtstamp_validate(const struct hwtstamp_config *cfg) { - struct hwtstamp_config cfg; enum hwtstamp_tx_types tx_type; enum hwtstamp_rx_filters rx_filter; int tx_type_valid = 0; int rx_filter_valid = 0; - if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg))) - return -EFAULT; - - if (cfg.flags & ~HWTSTAMP_FLAG_MASK) + if (cfg->flags & ~HWTSTAMP_FLAG_MASK) return -EINVAL; - tx_type = cfg.tx_type; - rx_filter = cfg.rx_filter; + tx_type = cfg->tx_type; + rx_filter = cfg->rx_filter; switch (tx_type) { case HWTSTAMP_TX_OFF: @@ -263,9 +259,13 @@ static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr) static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) { + struct hwtstamp_config cfg; int err; - err = net_hwtstamp_validate(ifr); + if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg))) + return -EFAULT; + + err = net_hwtstamp_validate(&cfg); if (err) return err; -- cgit v1.2.3 From c4bffeaa8d50b7279c5a76597efa4b06e709df63 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sun, 2 Apr 2023 15:37:53 +0300 Subject: net: add struct kernel_hwtstamp_config and make net_hwtstamp_validate() use it Jakub Kicinski suggested that we may want to add new UAPI for controlling hardware timestamping through netlink in the future, and in that case, we will be limited to the struct hwtstamp_config that is currently passed in fixed binary format through the SIOCGHWTSTAMP and SIOCSHWTSTAMP ioctls. It would be good if new kernel code already started operating on an extensible kernel variant of that structure, similar in concept to struct kernel_ethtool_coalesce vs struct ethtool_coalesce. Since struct hwtstamp_config is in include/uapi/linux/net_tstamp.h, here we introduce include/linux/net_tstamp.h which shadows that other header, but also includes it, so that existing includers of this header work as before. In addition to that, we add the definition for the kernel-only structure, and a helper which translates all fields by manual copying. I am doing a manual copy in order to not force the alignment (or type) of the fields of struct kernel_hwtstamp_config to be the same as of struct hwtstamp_config, even though now, they are the same. Link: https://lore.kernel.org/netdev/20230330223519.36ce7d23@kernel.org/ Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- include/linux/net_tstamp.h | 33 +++++++++++++++++++++++++++++++++ net/core/dev_ioctl.c | 7 +++++-- 2 files changed, 38 insertions(+), 2 deletions(-) create mode 100644 include/linux/net_tstamp.h (limited to 'net/core/dev_ioctl.c') diff --git a/include/linux/net_tstamp.h b/include/linux/net_tstamp.h new file mode 100644 index 000000000000..fd67f3cc0c4b --- /dev/null +++ b/include/linux/net_tstamp.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _LINUX_NET_TIMESTAMPING_H_ +#define _LINUX_NET_TIMESTAMPING_H_ + +#include + +/** + * struct kernel_hwtstamp_config - Kernel copy of struct hwtstamp_config + * + * @flags: see struct hwtstamp_config + * @tx_type: see struct hwtstamp_config + * @rx_filter: see struct hwtstamp_config + * + * Prefer using this structure for in-kernel processing of hardware + * timestamping configuration, over the inextensible struct hwtstamp_config + * exposed to the %SIOCGHWTSTAMP and %SIOCSHWTSTAMP ioctl UAPI. + */ +struct kernel_hwtstamp_config { + int flags; + int tx_type; + int rx_filter; +}; + +static inline void hwtstamp_config_to_kernel(struct kernel_hwtstamp_config *kernel_cfg, + const struct hwtstamp_config *cfg) +{ + kernel_cfg->flags = cfg->flags; + kernel_cfg->tx_type = cfg->tx_type; + kernel_cfg->rx_filter = cfg->rx_filter; +} + +#endif /* _LINUX_NET_TIMESTAMPING_H_ */ diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 34a0da5fbcfc..c532ef4d5dff 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -183,7 +183,7 @@ static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cm return err; } -static int net_hwtstamp_validate(const struct hwtstamp_config *cfg) +static int net_hwtstamp_validate(const struct kernel_hwtstamp_config *cfg) { enum hwtstamp_tx_types tx_type; enum hwtstamp_rx_filters rx_filter; @@ -259,13 +259,16 @@ static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr) static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) { + struct kernel_hwtstamp_config kernel_cfg; struct hwtstamp_config cfg; int err; if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg))) return -EFAULT; - err = net_hwtstamp_validate(&cfg); + hwtstamp_config_to_kernel(&kernel_cfg, &cfg); + + err = net_hwtstamp_validate(&kernel_cfg); if (err) return err; -- cgit v1.2.3 From 88c0a6b503b7f4fffb68a8d49c3987870c5b1d6b Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sun, 2 Apr 2023 15:37:55 +0300 Subject: net: create a netdev notifier for DSA to reject PTP on DSA master The fact that PTP 2-step TX timestamping is broken on DSA switches if the master also timestamps the same packets is documented by commit f685e609a301 ("net: dsa: Deny PTP on master if switch supports it"). We attempt to help the users avoid shooting themselves in the foot by making DSA reject the timestamping ioctls on an interface that is a DSA master, and the switch tree beneath it contains switches which are aware of PTP. The only problem is that there isn't an established way of intercepting ndo_eth_ioctl calls, so DSA creates avoidable burden upon the network stack by creating a struct dsa_netdevice_ops with overlaid function pointers that are manually checked from the relevant call sites. There used to be 2 such dsa_netdevice_ops, but now, ndo_eth_ioctl is the only one left. There is an ongoing effort to migrate driver-visible hardware timestamping control from the ndo_eth_ioctl() based API to a new ndo_hwtstamp_set() model, but DSA actively prevents that migration, since dsa_master_ioctl() is currently coded to manually call the master's legacy ndo_eth_ioctl(), and so, whenever a network device driver would be converted to the new API, DSA's restrictions would be circumvented, because any device could be used as a DSA master. The established way for unrelated modules to react on a net device event is via netdevice notifiers. So we create a new notifier which gets called whenever there is an attempt to change hardware timestamping settings on a device. Finally, there is another reason why a netdev notifier will be a good idea, besides strictly DSA, and this has to do with PHY timestamping. With ndo_eth_ioctl(), all MAC drivers must manually call phy_has_hwtstamp() before deciding whether to act upon SIOCSHWTSTAMP, otherwise they must pass this ioctl to the PHY driver via phy_mii_ioctl(). With the new ndo_hwtstamp_set() API, it will be desirable to simply not make any calls into the MAC device driver when timestamping should be performed at the PHY level. But there exist drivers, such as the lan966x switch, which need to install packet traps for PTP regardless of whether they are the layer that provides the hardware timestamps, or the PHY is. That would be impossible to support with the new API. The proposal there, too, is to introduce a netdev notifier which acts as a better cue for switching drivers to add or remove PTP packet traps, than ndo_hwtstamp_set(). The one introduced here "almost" works there as well, except for the fact that packet traps should only be installed if the PHY driver succeeded to enable hardware timestamping, whereas here, we need to deny hardware timestamping on the DSA master before it actually gets enabled. This is why this notifier is called "PRE_", and the notifier that would get used for PHY timestamping and packet traps would be called NETDEV_CHANGE_HWTSTAMP. This isn't a new concept, for example NETDEV_CHANGEUPPER and NETDEV_PRECHANGEUPPER do the same thing. In expectation of future netlink UAPI, we also pass a non-NULL extack pointer to the netdev notifier, and we make DSA populate it with an informative reason for the rejection. To avoid making it go to waste, we make the ioctl-based dev_set_hwtstamp() create a fake extack and print the message to the kernel log. Link: https://lore.kernel.org/netdev/20230401191215.tvveoi3lkawgg6g4@skbuf/ Link: https://lore.kernel.org/netdev/20230310164451.ls7bbs6pdzs4m6pw@skbuf/ Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- include/linux/netdevice.h | 9 ++++++++- include/net/dsa.h | 51 ----------------------------------------------- net/core/dev.c | 8 +++----- net/core/dev_ioctl.c | 16 +++++++++++++-- net/dsa/master.c | 50 ++++++++++++++-------------------------------- net/dsa/master.h | 3 +++ net/dsa/slave.c | 11 ++++++++++ 7 files changed, 54 insertions(+), 94 deletions(-) (limited to 'net/core/dev_ioctl.c') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 62e093a6d6d1..a740be3bb911 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2878,6 +2878,7 @@ enum netdev_cmd { NETDEV_OFFLOAD_XSTATS_REPORT_USED, NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, NETDEV_XDP_FEAT_CHANGE, + NETDEV_PRE_CHANGE_HWTSTAMP, }; const char *netdev_cmd_to_name(enum netdev_cmd cmd); @@ -2928,6 +2929,11 @@ struct netdev_notifier_pre_changeaddr_info { const unsigned char *dev_addr; }; +struct netdev_notifier_hwtstamp_info { + struct netdev_notifier_info info; /* must be first */ + struct kernel_hwtstamp_config *config; +}; + enum netdev_offload_xstats_type { NETDEV_OFFLOAD_XSTATS_TYPE_L3 = 1, }; @@ -2984,7 +2990,8 @@ netdev_notifier_info_to_extack(const struct netdev_notifier_info *info) } int call_netdevice_notifiers(unsigned long val, struct net_device *dev); - +int call_netdevice_notifiers_info(unsigned long val, + struct netdev_notifier_info *info); extern rwlock_t dev_base_lock; /* Device list lock */ diff --git a/include/net/dsa.h b/include/net/dsa.h index a15f17a38eca..8903053fa5aa 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -109,16 +109,6 @@ struct dsa_device_ops { bool promisc_on_master; }; -/* This structure defines the control interfaces that are overlayed by the - * DSA layer on top of the DSA CPU/management net_device instance. This is - * used by the core net_device layer while calling various net_device_ops - * function pointers. - */ -struct dsa_netdevice_ops { - int (*ndo_eth_ioctl)(struct net_device *dev, struct ifreq *ifr, - int cmd); -}; - struct dsa_lag { struct net_device *dev; unsigned int id; @@ -317,11 +307,6 @@ struct dsa_port { */ const struct ethtool_ops *orig_ethtool_ops; - /* - * Original copy of the master netdev net_device_ops - */ - const struct dsa_netdevice_ops *netdev_ops; - /* List of MAC addresses that must be forwarded on this port. * These are only valid on CPU ports and DSA links. */ @@ -1339,42 +1324,6 @@ static inline void dsa_tag_generic_flow_dissect(const struct sk_buff *skb, #endif } -#if IS_ENABLED(CONFIG_NET_DSA) -static inline int __dsa_netdevice_ops_check(struct net_device *dev) -{ - int err = -EOPNOTSUPP; - - if (!dev->dsa_ptr) - return err; - - if (!dev->dsa_ptr->netdev_ops) - return err; - - return 0; -} - -static inline int dsa_ndo_eth_ioctl(struct net_device *dev, struct ifreq *ifr, - int cmd) -{ - const struct dsa_netdevice_ops *ops; - int err; - - err = __dsa_netdevice_ops_check(dev); - if (err) - return err; - - ops = dev->dsa_ptr->netdev_ops; - - return ops->ndo_eth_ioctl(dev, ifr, cmd); -} -#else -static inline int dsa_ndo_eth_ioctl(struct net_device *dev, struct ifreq *ifr, - int cmd) -{ - return -EOPNOTSUPP; -} -#endif - void dsa_unregister_switch(struct dsa_switch *ds); int dsa_register_switch(struct dsa_switch *ds); void dsa_switch_shutdown(struct dsa_switch *ds); diff --git a/net/core/dev.c b/net/core/dev.c index 0c4b21291348..7ce5985be84b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -160,8 +160,6 @@ struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; struct list_head ptype_all __read_mostly; /* Taps */ static int netif_rx_internal(struct sk_buff *skb); -static int call_netdevice_notifiers_info(unsigned long val, - struct netdev_notifier_info *info); static int call_netdevice_notifiers_extack(unsigned long val, struct net_device *dev, struct netlink_ext_ack *extack); @@ -1614,7 +1612,7 @@ const char *netdev_cmd_to_name(enum netdev_cmd cmd) N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) - N(XDP_FEAT_CHANGE) + N(XDP_FEAT_CHANGE) N(PRE_CHANGE_HWTSTAMP) } #undef N return "UNKNOWN_NETDEV_EVENT"; @@ -1919,8 +1917,8 @@ static void move_netdevice_notifiers_dev_net(struct net_device *dev, * are as for raw_notifier_call_chain(). */ -static int call_netdevice_notifiers_info(unsigned long val, - struct netdev_notifier_info *info) +int call_netdevice_notifiers_info(unsigned long val, + struct netdev_notifier_info *info) { struct net *net = dev_net(info->dev); int ret; diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index c532ef4d5dff..6d772837eb3f 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -259,7 +259,11 @@ static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr) static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) { + struct netdev_notifier_hwtstamp_info info = { + .info.dev = dev, + }; struct kernel_hwtstamp_config kernel_cfg; + struct netlink_ext_ack extack = {}; struct hwtstamp_config cfg; int err; @@ -272,9 +276,17 @@ static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) if (err) return err; - err = dsa_ndo_eth_ioctl(dev, ifr, SIOCSHWTSTAMP); - if (err != -EOPNOTSUPP) + info.info.extack = &extack; + info.config = &kernel_cfg; + + err = call_netdevice_notifiers_info(NETDEV_PRE_CHANGE_HWTSTAMP, + &info.info); + err = notifier_to_errno(err); + if (err) { + if (extack._msg) + netdev_err(dev, "%s\n", extack._msg); return err; + } return dev_eth_ioctl(dev, ifr, SIOCSHWTSTAMP); } diff --git a/net/dsa/master.c b/net/dsa/master.c index e397641382ca..c2cabe6248b1 100644 --- a/net/dsa/master.c +++ b/net/dsa/master.c @@ -195,38 +195,31 @@ static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset, } } -static int dsa_master_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) +/* Deny PTP operations on master if there is at least one switch in the tree + * that is PTP capable. + */ +int dsa_master_pre_change_hwtstamp(struct net_device *dev, + const struct kernel_hwtstamp_config *config, + struct netlink_ext_ack *extack) { struct dsa_port *cpu_dp = dev->dsa_ptr; struct dsa_switch *ds = cpu_dp->ds; struct dsa_switch_tree *dst; - int err = -EOPNOTSUPP; struct dsa_port *dp; dst = ds->dst; - switch (cmd) { - case SIOCGHWTSTAMP: - case SIOCSHWTSTAMP: - /* Deny PTP operations on master if there is at least one - * switch in the tree that is PTP capable. - */ - list_for_each_entry(dp, &dst->ports, list) - if (dsa_port_supports_hwtstamp(dp)) - return -EBUSY; - break; + list_for_each_entry(dp, &dst->ports, list) { + if (dsa_port_supports_hwtstamp(dp)) { + NL_SET_ERR_MSG(extack, + "HW timestamping not allowed on DSA master when switch supports the operation"); + return -EBUSY; + } } - if (dev->netdev_ops->ndo_eth_ioctl) - err = dev->netdev_ops->ndo_eth_ioctl(dev, ifr, cmd); - - return err; + return 0; } -static const struct dsa_netdevice_ops dsa_netdev_ops = { - .ndo_eth_ioctl = dsa_master_ioctl, -}; - static int dsa_master_ethtool_setup(struct net_device *dev) { struct dsa_port *cpu_dp = dev->dsa_ptr; @@ -267,15 +260,6 @@ static void dsa_master_ethtool_teardown(struct net_device *dev) cpu_dp->orig_ethtool_ops = NULL; } -static void dsa_netdev_ops_set(struct net_device *dev, - const struct dsa_netdevice_ops *ops) -{ - if (netif_is_lag_master(dev)) - return; - - dev->dsa_ptr->netdev_ops = ops; -} - /* Keep the master always promiscuous if the tagging protocol requires that * (garbles MAC DA) or if it doesn't support unicast filtering, case in which * it would revert to promiscuous mode as soon as we call dev_uc_add() on it @@ -414,16 +398,13 @@ int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp) if (ret) goto out_err_reset_promisc; - dsa_netdev_ops_set(dev, &dsa_netdev_ops); - ret = sysfs_create_group(&dev->dev.kobj, &dsa_group); if (ret) - goto out_err_ndo_teardown; + goto out_err_ethtool_teardown; return ret; -out_err_ndo_teardown: - dsa_netdev_ops_set(dev, NULL); +out_err_ethtool_teardown: dsa_master_ethtool_teardown(dev); out_err_reset_promisc: dsa_master_set_promiscuity(dev, -1); @@ -433,7 +414,6 @@ out_err_reset_promisc: void dsa_master_teardown(struct net_device *dev) { sysfs_remove_group(&dev->dev.kobj, &dsa_group); - dsa_netdev_ops_set(dev, NULL); dsa_master_ethtool_teardown(dev); dsa_master_reset_mtu(dev); dsa_master_set_promiscuity(dev, -1); diff --git a/net/dsa/master.h b/net/dsa/master.h index 3fc0e610b5b5..80842f4e27f7 100644 --- a/net/dsa/master.h +++ b/net/dsa/master.h @@ -15,5 +15,8 @@ int dsa_master_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp, struct netlink_ext_ack *extack); void dsa_master_lag_teardown(struct net_device *lag_dev, struct dsa_port *cpu_dp); +int dsa_master_pre_change_hwtstamp(struct net_device *dev, + const struct kernel_hwtstamp_config *config, + struct netlink_ext_ack *extack); #endif diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 165bb2cb8431..8abc1658ac47 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -3289,6 +3289,7 @@ static int dsa_master_changeupper(struct net_device *dev, static int dsa_slave_netdevice_event(struct notifier_block *nb, unsigned long event, void *ptr) { + struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr); struct net_device *dev = netdev_notifier_info_to_dev(ptr); switch (event) { @@ -3418,6 +3419,16 @@ static int dsa_slave_netdevice_event(struct notifier_block *nb, return NOTIFY_OK; } + case NETDEV_PRE_CHANGE_HWTSTAMP: { + struct netdev_notifier_hwtstamp_info *info = ptr; + int err; + + if (!netdev_uses_dsa(dev)) + return NOTIFY_DONE; + + err = dsa_master_pre_change_hwtstamp(dev, info->config, extack); + return notifier_from_errno(err); + } default: break; } -- cgit v1.2.3 From 5a17818682cf43ad0fdd6035945f3b7a8c9dc5e9 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Thu, 6 Apr 2023 14:42:46 +0300 Subject: net: dsa: replace NETDEV_PRE_CHANGE_HWTSTAMP notifier with a stub There was a sort of rush surrounding commit 88c0a6b503b7 ("net: create a netdev notifier for DSA to reject PTP on DSA master"), due to a desire to convert DSA's attempt to deny TX timestamping on a DSA master to something that doesn't block the kernel-wide API conversion from ndo_eth_ioctl() to ndo_hwtstamp_set(). What was required was a mechanism that did not depend on ndo_eth_ioctl(), and what was provided was a mechanism that did not depend on ndo_eth_ioctl(), while at the same time introducing something that wasn't absolutely necessary - a new netdev notifier. There have been objections from Jakub Kicinski that using notifiers in general when they are not absolutely necessary creates complications to the control flow and difficulties to maintainers who look at the code. So there is a desire to not use notifiers. In addition to that, the notifier chain gets called even if there is no DSA in the system and no one is interested in applying any restriction. Take the model of udp_tunnel_nic_ops and introduce a stub mechanism, through which net/core/dev_ioctl.c can call into DSA even when CONFIG_NET_DSA=m. Compared to the code that existed prior to the notifier conversion, aka what was added in commits: - 4cfab3566710 ("net: dsa: Add wrappers for overloaded ndo_ops") - 3369afba1e46 ("net: Call into DSA netdevice_ops wrappers") this is different because we are not overloading any struct net_device_ops of the DSA master anymore, but rather, we are exposing a rather specific functionality which is orthogonal to which API is used to enable it - ndo_eth_ioctl() or ndo_hwtstamp_set(). Also, what is similar is that both approaches use function pointers to get from built-in code to DSA. There is no point in replicating the function pointers towards __dsa_master_hwtstamp_validate() once for every CPU port (dev->dsa_ptr). Instead, it is sufficient to introduce a singleton struct dsa_stubs, built into the kernel, which contains a single function pointer to __dsa_master_hwtstamp_validate(). I find this approach preferable to what we had originally, because dev->dsa_ptr->netdev_ops->ndo_do_ioctl() used to require going through struct dsa_port (dev->dsa_ptr), and so, this was incompatible with any attempts to add any data encapsulation and hide DSA data structures from the outside world. Link: https://lore.kernel.org/netdev/20230403083019.120b72fd@kernel.org/ Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- include/linux/netdevice.h | 6 ------ include/net/dsa_stubs.h | 48 +++++++++++++++++++++++++++++++++++++++++++++++ net/Makefile | 2 +- net/core/dev.c | 2 +- net/core/dev_ioctl.c | 12 ++---------- net/dsa/Makefile | 6 ++++++ net/dsa/dsa.c | 19 +++++++++++++++++++ net/dsa/master.c | 2 +- net/dsa/master.h | 2 +- net/dsa/slave.c | 11 ----------- net/dsa/stubs.c | 10 ++++++++++ 11 files changed, 89 insertions(+), 31 deletions(-) create mode 100644 include/net/dsa_stubs.h create mode 100644 net/dsa/stubs.c (limited to 'net/core/dev_ioctl.c') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index a740be3bb911..1c25b39681b3 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2878,7 +2878,6 @@ enum netdev_cmd { NETDEV_OFFLOAD_XSTATS_REPORT_USED, NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, NETDEV_XDP_FEAT_CHANGE, - NETDEV_PRE_CHANGE_HWTSTAMP, }; const char *netdev_cmd_to_name(enum netdev_cmd cmd); @@ -2929,11 +2928,6 @@ struct netdev_notifier_pre_changeaddr_info { const unsigned char *dev_addr; }; -struct netdev_notifier_hwtstamp_info { - struct netdev_notifier_info info; /* must be first */ - struct kernel_hwtstamp_config *config; -}; - enum netdev_offload_xstats_type { NETDEV_OFFLOAD_XSTATS_TYPE_L3 = 1, }; diff --git a/include/net/dsa_stubs.h b/include/net/dsa_stubs.h new file mode 100644 index 000000000000..361811750a54 --- /dev/null +++ b/include/net/dsa_stubs.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * include/net/dsa_stubs.h - Stubs for the Distributed Switch Architecture framework + */ + +#include +#include +#include +#include + +#if IS_ENABLED(CONFIG_NET_DSA) + +extern const struct dsa_stubs *dsa_stubs; + +struct dsa_stubs { + int (*master_hwtstamp_validate)(struct net_device *dev, + const struct kernel_hwtstamp_config *config, + struct netlink_ext_ack *extack); +}; + +static inline int dsa_master_hwtstamp_validate(struct net_device *dev, + const struct kernel_hwtstamp_config *config, + struct netlink_ext_ack *extack) +{ + if (!netdev_uses_dsa(dev)) + return 0; + + /* rtnl_lock() is a sufficient guarantee, because as long as + * netdev_uses_dsa() returns true, the dsa_core module is still + * registered, and so, dsa_unregister_stubs() couldn't have run. + * For netdev_uses_dsa() to start returning false, it would imply that + * dsa_master_teardown() has executed, which requires rtnl_lock(). + */ + ASSERT_RTNL(); + + return dsa_stubs->master_hwtstamp_validate(dev, config, extack); +} + +#else + +static inline int dsa_master_hwtstamp_validate(struct net_device *dev, + const struct kernel_hwtstamp_config *config, + struct netlink_ext_ack *extack) +{ + return 0; +} + +#endif diff --git a/net/Makefile b/net/Makefile index 0914bea9c335..87592009366f 100644 --- a/net/Makefile +++ b/net/Makefile @@ -24,7 +24,7 @@ obj-$(CONFIG_PACKET) += packet/ obj-$(CONFIG_NET_KEY) += key/ obj-$(CONFIG_BRIDGE) += bridge/ obj-$(CONFIG_NET_DEVLINK) += devlink/ -obj-$(CONFIG_NET_DSA) += dsa/ +obj-y += dsa/ obj-$(CONFIG_ATALK) += appletalk/ obj-$(CONFIG_X25) += x25/ obj-$(CONFIG_LAPB) += lapb/ diff --git a/net/core/dev.c b/net/core/dev.c index 7ce5985be84b..480600a075ce 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1612,7 +1612,7 @@ const char *netdev_cmd_to_name(enum netdev_cmd cmd) N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) - N(XDP_FEAT_CHANGE) N(PRE_CHANGE_HWTSTAMP) + N(XDP_FEAT_CHANGE) } #undef N return "UNKNOWN_NETDEV_EVENT"; diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 6d772837eb3f..3730945ee294 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -7,7 +7,7 @@ #include #include #include -#include +#include #include #include "dev.h" @@ -259,9 +259,6 @@ static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr) static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) { - struct netdev_notifier_hwtstamp_info info = { - .info.dev = dev, - }; struct kernel_hwtstamp_config kernel_cfg; struct netlink_ext_ack extack = {}; struct hwtstamp_config cfg; @@ -276,12 +273,7 @@ static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) if (err) return err; - info.info.extack = &extack; - info.config = &kernel_cfg; - - err = call_netdevice_notifiers_info(NETDEV_PRE_CHANGE_HWTSTAMP, - &info.info); - err = notifier_to_errno(err); + err = dsa_master_hwtstamp_validate(dev, &kernel_cfg, &extack); if (err) { if (extack._msg) netdev_err(dev, "%s\n", extack._msg); diff --git a/net/dsa/Makefile b/net/dsa/Makefile index cc7e93a562fe..3835de286116 100644 --- a/net/dsa/Makefile +++ b/net/dsa/Makefile @@ -1,4 +1,10 @@ # SPDX-License-Identifier: GPL-2.0 + +# the stubs are built-in whenever DSA is built-in or module +ifdef CONFIG_NET_DSA +obj-y := stubs.o +endif + # the core obj-$(CONFIG_NET_DSA) += dsa_core.o dsa_core-y += \ diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c index e5f156940c67..ab1afe67fd18 100644 --- a/net/dsa/dsa.c +++ b/net/dsa/dsa.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include "devlink.h" @@ -1702,6 +1703,20 @@ bool dsa_mdb_present_in_other_db(struct dsa_switch *ds, int port, } EXPORT_SYMBOL_GPL(dsa_mdb_present_in_other_db); +static const struct dsa_stubs __dsa_stubs = { + .master_hwtstamp_validate = __dsa_master_hwtstamp_validate, +}; + +static void dsa_register_stubs(void) +{ + dsa_stubs = &__dsa_stubs; +} + +static void dsa_unregister_stubs(void) +{ + dsa_stubs = NULL; +} + static int __init dsa_init_module(void) { int rc; @@ -1721,6 +1736,8 @@ static int __init dsa_init_module(void) if (rc) goto netlink_register_fail; + dsa_register_stubs(); + return 0; netlink_register_fail: @@ -1735,6 +1752,8 @@ module_init(dsa_init_module); static void __exit dsa_cleanup_module(void) { + dsa_unregister_stubs(); + rtnl_link_unregister(&dsa_link_ops); dsa_slave_unregister_notifier(); diff --git a/net/dsa/master.c b/net/dsa/master.c index c2cabe6248b1..6be89ab0cc01 100644 --- a/net/dsa/master.c +++ b/net/dsa/master.c @@ -198,7 +198,7 @@ static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset, /* Deny PTP operations on master if there is at least one switch in the tree * that is PTP capable. */ -int dsa_master_pre_change_hwtstamp(struct net_device *dev, +int __dsa_master_hwtstamp_validate(struct net_device *dev, const struct kernel_hwtstamp_config *config, struct netlink_ext_ack *extack) { diff --git a/net/dsa/master.h b/net/dsa/master.h index 80842f4e27f7..76e39d3ec909 100644 --- a/net/dsa/master.h +++ b/net/dsa/master.h @@ -15,7 +15,7 @@ int dsa_master_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp, struct netlink_ext_ack *extack); void dsa_master_lag_teardown(struct net_device *lag_dev, struct dsa_port *cpu_dp); -int dsa_master_pre_change_hwtstamp(struct net_device *dev, +int __dsa_master_hwtstamp_validate(struct net_device *dev, const struct kernel_hwtstamp_config *config, struct netlink_ext_ack *extack); diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 8abc1658ac47..165bb2cb8431 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -3289,7 +3289,6 @@ static int dsa_master_changeupper(struct net_device *dev, static int dsa_slave_netdevice_event(struct notifier_block *nb, unsigned long event, void *ptr) { - struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr); struct net_device *dev = netdev_notifier_info_to_dev(ptr); switch (event) { @@ -3419,16 +3418,6 @@ static int dsa_slave_netdevice_event(struct notifier_block *nb, return NOTIFY_OK; } - case NETDEV_PRE_CHANGE_HWTSTAMP: { - struct netdev_notifier_hwtstamp_info *info = ptr; - int err; - - if (!netdev_uses_dsa(dev)) - return NOTIFY_DONE; - - err = dsa_master_pre_change_hwtstamp(dev, info->config, extack); - return notifier_from_errno(err); - } default: break; } diff --git a/net/dsa/stubs.c b/net/dsa/stubs.c new file mode 100644 index 000000000000..2ed8a6c85fbf --- /dev/null +++ b/net/dsa/stubs.c @@ -0,0 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Stubs for DSA functionality called by the core network stack. + * These are necessary because CONFIG_NET_DSA can be a module, and built-in + * code cannot directly call symbols exported by modules. + */ +#include + +const struct dsa_stubs *dsa_stubs; +EXPORT_SYMBOL_GPL(dsa_stubs); -- cgit v1.2.3