include/net/kcm.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Kernel Connection Multiplexor
   4  *
   5  * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
   6  */
   7
   8 #ifndef __NET_KCM_H_
   9 #define __NET_KCM_H_
  10
  11 #include <linux/skbuff.h>
  12 #include <net/sock.h>
  13 #include <net/strparser.h>
  14 #include <uapi/linux/kcm.h>
  15
  16 extern unsigned int kcm_net_id;
  17
  18 #define KCM_STATS_ADD(stat, count) ((stat) += (count))
  19 #define KCM_STATS_INCR(stat) ((stat)++)
  20
  21 struct kcm_psock_stats {
  22         unsigned long long tx_msgs;
  23         unsigned long long tx_bytes;
  24         unsigned long long reserved;
  25         unsigned long long unreserved;
  26         unsigned int tx_aborts;
  27 };
  28
  29 struct kcm_mux_stats {
  30         unsigned long long rx_msgs;
  31         unsigned long long rx_bytes;
  32         unsigned long long tx_msgs;
  33         unsigned long long tx_bytes;
  34         unsigned int rx_ready_drops;
  35         unsigned int tx_retries;
  36         unsigned int psock_attach;
  37         unsigned int psock_unattach_rsvd;
  38         unsigned int psock_unattach;
  39 };
  40
  41 struct kcm_stats {
  42         unsigned long long rx_msgs;
  43         unsigned long long rx_bytes;
  44         unsigned long long tx_msgs;
  45         unsigned long long tx_bytes;
  46 };
  47
  48 struct kcm_tx_msg {
  49         unsigned int sent;
  50         unsigned int frag_offset;
  51         unsigned int msg_flags;
  52         bool started_tx;
  53         struct sk_buff *frag_skb;
  54         struct sk_buff *last_skb;
  55 };
  56
  57 /* Socket structure for KCM client sockets */
  58 struct kcm_sock {
  59         struct sock sk;
  60         struct kcm_mux *mux;
  61         struct list_head kcm_sock_list;
  62         int index;
  63         u32 done : 1;
  64         struct work_struct done_work;
  65
  66         struct kcm_stats stats;
  67
  68         /* Transmit */
  69         struct kcm_psock *tx_psock;
  70         struct work_struct tx_work;
  71         struct list_head wait_psock_list;
  72         struct sk_buff *seq_skb;
  73         struct mutex tx_mutex;
  74         u32 tx_stopped : 1;
  75
  76         /* Don't use bit fields here, these are set under different locks */
  77         bool tx_wait;
  78         bool tx_wait_more;
  79
  80         /* Receive */
  81         struct kcm_psock *rx_psock;
  82         struct list_head wait_rx_list; /* KCMs waiting for receiving */
  83         bool rx_wait;
  84         u32 rx_disabled : 1;
  85 };
  86
  87 struct bpf_prog;
  88
  89 /* Structure for an attached lower socket */
  90 struct kcm_psock {
  91         struct sock *sk;
  92         struct strparser strp;
  93         struct kcm_mux *mux;
  94         int index;
  95
  96         u32 tx_stopped : 1;
  97         u32 done : 1;
  98         u32 unattaching : 1;
  99
 100         void (*save_state_change)(struct sock *sk);
 101         void (*save_data_ready)(struct sock *sk);
 102         void (*save_write_space)(struct sock *sk);
 103
 104         struct list_head psock_list;
 105
 106         struct kcm_psock_stats stats;
 107
 108         /* Receive */
 109         struct list_head psock_ready_list;
 110         struct bpf_prog *bpf_prog;
 111         struct kcm_sock *rx_kcm;
 112         unsigned long long saved_rx_bytes;
 113         unsigned long long saved_rx_msgs;
 114         struct sk_buff *ready_rx_msg;
 115
 116         /* Transmit */
 117         struct kcm_sock *tx_kcm;
 118         struct list_head psock_avail_list;
 119         unsigned long long saved_tx_bytes;
 120         unsigned long long saved_tx_msgs;
 121 };
 122
 123 /* Per net MUX list */
 124 struct kcm_net {
 125         struct mutex mutex;
 126         struct kcm_psock_stats aggregate_psock_stats;
 127         struct kcm_mux_stats aggregate_mux_stats;
 128         struct strp_aggr_stats aggregate_strp_stats;
 129         struct list_head mux_list;
 130         int count;
 131 };
 132
 133 /* Structure for a MUX */
 134 struct kcm_mux {
 135         struct list_head kcm_mux_list;
 136         struct rcu_head rcu;
 137         struct kcm_net *knet;
 138
 139         struct list_head kcm_socks;     /* All KCM sockets on MUX */
 140         int kcm_socks_cnt;              /* Total KCM socket count for MUX */
 141         struct list_head psocks;        /* List of all psocks on MUX */
 142         int psocks_cnt;         /* Total attached sockets */
 143
 144         struct kcm_mux_stats stats;
 145         struct kcm_psock_stats aggregate_psock_stats;
 146         struct strp_aggr_stats aggregate_strp_stats;
 147
 148         /* Receive */
 149         spinlock_t rx_lock ____cacheline_aligned_in_smp;
 150         struct list_head kcm_rx_waiters; /* KCMs waiting for receiving */
 151         struct list_head psocks_ready;  /* List of psocks with a msg ready */
 152         struct sk_buff_head rx_hold_queue;
 153
 154         /* Transmit */
 155         spinlock_t  lock ____cacheline_aligned_in_smp;  /* TX and mux locking */
 156         struct list_head psocks_avail;  /* List of available psocks */
 157         struct list_head kcm_tx_waiters; /* KCMs waiting for a TX psock */
 158 };
 159
 160 #ifdef CONFIG_PROC_FS
 161 int kcm_proc_init(void);
 162 void kcm_proc_exit(void);
 163 #else
 164 static inline int kcm_proc_init(void) { return 0; }
 165 static inline void kcm_proc_exit(void) { }
 166 #endif
 167
 168 static inline void aggregate_psock_stats(struct kcm_psock_stats *stats,
 169                                          struct kcm_psock_stats *agg_stats)
 170 {
 171         /* Save psock statistics in the mux when psock is being unattached. */
 172
 173 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
 174         SAVE_PSOCK_STATS(tx_msgs);
 175         SAVE_PSOCK_STATS(tx_bytes);
 176         SAVE_PSOCK_STATS(reserved);
 177         SAVE_PSOCK_STATS(unreserved);
 178         SAVE_PSOCK_STATS(tx_aborts);
 179 #undef SAVE_PSOCK_STATS
 180 }
 181
 182 static inline void aggregate_mux_stats(struct kcm_mux_stats *stats,
 183                                        struct kcm_mux_stats *agg_stats)
 184 {
 185         /* Save psock statistics in the mux when psock is being unattached. */
 186
 187 #define SAVE_MUX_STATS(_stat) (agg_stats->_stat += stats->_stat)
 188         SAVE_MUX_STATS(rx_msgs);
 189         SAVE_MUX_STATS(rx_bytes);
 190         SAVE_MUX_STATS(tx_msgs);
 191         SAVE_MUX_STATS(tx_bytes);
 192         SAVE_MUX_STATS(rx_ready_drops);
 193         SAVE_MUX_STATS(psock_attach);
 194         SAVE_MUX_STATS(psock_unattach_rsvd);
 195         SAVE_MUX_STATS(psock_unattach);
 196 #undef SAVE_MUX_STATS
 197 }
 198
 199 #endif /* __NET_KCM_H_ */