/* * Copyright (c) 2007-2014 Nicira, Inc. * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA */ #ifndef DATAPATH_H #define DATAPATH_H 1 #include #include #include #include #include #include #include #include "conntrack.h" #include "flow.h" #include "flow_table.h" #define DP_MAX_PORTS USHRT_MAX #define DP_VPORT_HASH_BUCKETS 1024 #define SAMPLE_ACTION_DEPTH 3 /** * struct dp_stats_percpu - per-cpu packet processing statistics for a given * datapath. * @n_hit: Number of received packets for which a matching flow was found in * the flow table. * @n_miss: Number of received packets that had no matching flow in the flow * table. The sum of @n_hit and @n_miss is the number of packets that have * been received by the datapath. * @n_lost: Number of received packets that had no matching flow in the flow * table that could not be sent to userspace (normally due to an overflow in * one of the datapath's queues). * @n_mask_hit: Number of masks looked up for flow match. * @n_mask_hit / (@n_hit + @n_missed) will be the average masks looked * up per packet. */ struct dp_stats_percpu { u64 n_hit; u64 n_missed; u64 n_lost; u64 n_mask_hit; struct u64_stats_sync syncp; }; /** * struct datapath - datapath for flow-based packet switching * @rcu: RCU callback head for deferred destruction. * @list_node: Element in global 'dps' list. * @table: flow table. * @ports: Hash table for ports. %OVSP_LOCAL port always exists. Protected by * ovs_mutex and RCU. * @stats_percpu: Per-CPU datapath statistics. * @net: Reference to net namespace. * @max_headroom: the maximum headroom of all vports in this datapath; it will * be used by all the internal vports in this dp. * * Context: See the comment on locking at the top of datapath.c for additional * locking information. */ struct datapath { struct rcu_head rcu; struct list_head list_node; /* Flow table. */ struct flow_table table; /* Switch ports. */ struct hlist_head *ports; /* Stats. */ struct dp_stats_percpu __percpu *stats_percpu; /* Network namespace ref. */ possible_net_t net; u32 user_features; u32 max_headroom; }; /** * struct ovs_skb_cb - OVS data in skb CB * @input_vport: The original vport packet came in on. This value is cached * when a packet is received by OVS. * @mru: The maximum received fragement size; 0 if the packet is not * @cutlen: The number of bytes from the packet end to be removed. * fragmented. */ struct ovs_skb_cb { struct vport *input_vport; u16 mru; u32 cutlen; }; #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb) /** * struct dp_upcall - metadata to include with a packet to send to userspace * @cmd: One of %OVS_PACKET_CMD_*. * @userdata: If nonnull, its variable-length value is passed to userspace as * %OVS_PACKET_ATTR_USERDATA. * @portid: Netlink portid to which packet should be sent. If @portid is 0 * then no packet is sent and the packet is accounted in the datapath's @n_lost * counter. * @egress_tun_info: If nonnull, becomes %OVS_PACKET_ATTR_EGRESS_TUN_KEY. * @mru: If not zero, Maximum received IP fragment size. */ struct dp_upcall_info { struct ip_tunnel_info *egress_tun_info; const struct nlattr *userdata; const struct nlattr *actions; int actions_len; u32 portid; u8 cmd; u16 mru; }; /** * struct ovs_net - Per net-namespace data for ovs. * @dps: List of datapaths to enable dumping them all out. * Protected by genl_mutex. */ struct ovs_net { struct list_head dps; struct work_struct dp_notify_work; /* Module reference for configuring conntrack. */ bool xt_label; }; extern unsigned int ovs_net_id; void ovs_lock(void); void ovs_unlock(void); #ifdef CONFIG_LOCKDEP int lockdep_ovsl_is_held(void); #else #define lockdep_ovsl_is_held() 1 #endif #define ASSERT_OVSL() WARN_ON(!lockdep_ovsl_is_held()) #define ovsl_dereference(p) \ rcu_dereference_protected(p, lockdep_ovsl_is_held()) #define rcu_dereference_ovsl(p) \ rcu_dereference_check(p, lockdep_ovsl_is_held()) static inline struct net *ovs_dp_get_net(const struct datapath *dp) { return read_pnet(&dp->net); } static inline void ovs_dp_set_net(struct datapath *dp, struct net *net) { write_pnet(&dp->net, net); } struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no); static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no) { WARN_ON_ONCE(!rcu_read_lock_held()); return ovs_lookup_vport(dp, port_no); } static inline struct vport *ovs_vport_ovsl_rcu(const struct datapath *dp, int port_no) { WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held()); return ovs_lookup_vport(dp, port_no); } static inline struct vport *ovs_vport_ovsl(const struct datapath *dp, int port_no) { ASSERT_OVSL(); return ovs_lookup_vport(dp, port_no); } extern struct notifier_block ovs_dp_device_notifier; extern struct genl_family dp_vport_genl_family; void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key); void ovs_dp_detach_port(struct vport *); int ovs_dp_upcall(struct datapath *, struct sk_buff *, const struct sw_flow_key *, const struct dp_upcall_info *, uint32_t cutlen); const char *ovs_dp_name(const struct datapath *dp); struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq, u8 cmd); int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, const struct sw_flow_actions *, struct sw_flow_key *); void ovs_dp_notify_wq(struct work_struct *work); int action_fifos_init(void); void action_fifos_exit(void); /* 'KEY' must not have any bits set outside of the 'MASK' */ #define OVS_MASKED(OLD, KEY, MASK) ((KEY) | ((OLD) & ~(MASK))) #define OVS_SET_MASKED(OLD, KEY, MASK) ((OLD) = OVS_MASKED(OLD, KEY, MASK)) #define OVS_NLERR(logging_allowed, fmt, ...) \ do { \ if (logging_allowed && net_ratelimit()) \ pr_info("netlink: " fmt "\n", ##__VA_ARGS__); \ } while (0) #endif /* datapath.h */ blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'sound/core/misc.c')