/* SPDX-License-Identifier: GPL-2.0-or-later */
/* AF_RXRPC internal definitions
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#include <linux/atomic.h>
#include <linux/seqlock.h>
#include <linux/win_minmax.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <keys/rxrpc-type.h>
#include "protocol.h"

#define FCRYPT_BSIZE 8
struct rxrpc_crypt {
        union {
                u8      x[FCRYPT_BSIZE];
                __be32  n[2];
        };
} __attribute__((aligned(8)));

#define rxrpc_queue_work(WS)    queue_work(rxrpc_workqueue, (WS))
#define rxrpc_queue_delayed_work(WS,D)  \
        queue_delayed_work(rxrpc_workqueue, (WS), (D))

struct key_preparsed_payload;
struct rxrpc_connection;
struct rxrpc_txbuf;
struct rxrpc_txqueue;
struct rxgk_context;

/*
 * Mark applied to socket buffers in skb->mark.  skb->priority is used
 * to pass supplementary information.
 */
enum rxrpc_skb_mark {
        RXRPC_SKB_MARK_PACKET,          /* Received packet */
        RXRPC_SKB_MARK_ERROR,           /* Error notification */
        RXRPC_SKB_MARK_CHALLENGE,       /* Challenge notification */
        RXRPC_SKB_MARK_SERVICE_CONN_SECURED, /* Service connection response has been verified */
        RXRPC_SKB_MARK_REJECT_BUSY,     /* Reject with BUSY */
        RXRPC_SKB_MARK_REJECT_ABORT,    /* Reject with ABORT (code in skb->priority) */
        RXRPC_SKB_MARK_REJECT_CONN_ABORT, /* Reject with connection ABORT (code in skb->priority) */
};

/*
 * sk_state for RxRPC sockets
 */
enum {
        RXRPC_UNBOUND = 0,
        RXRPC_CLIENT_UNBOUND,           /* Unbound socket used as client */
        RXRPC_CLIENT_BOUND,             /* client local address bound */
        RXRPC_SERVER_BOUND,             /* server local address bound */
        RXRPC_SERVER_BOUND2,            /* second server local address bound */
        RXRPC_SERVER_LISTENING,         /* server listening for connections */
        RXRPC_SERVER_LISTEN_DISABLED,   /* server listening disabled */
        RXRPC_CLOSE,                    /* socket is being closed */
};

/*
 * Per-network namespace data.
 */
struct rxrpc_net {
        struct proc_dir_entry   *proc_net;      /* Subdir in /proc/net */
        u32                     epoch;          /* Local epoch for detecting local-end reset */
        struct list_head        calls;          /* List of calls active in this namespace */
        spinlock_t              call_lock;      /* Lock for ->calls */
        atomic_t                nr_calls;       /* Count of allocated calls */

        atomic_t                nr_conns;
        struct list_head        bundle_proc_list; /* List of bundles for proc */
        struct list_head        conn_proc_list; /* List of conns in this namespace for proc */
        struct list_head        service_conns;  /* Service conns in this namespace */
        rwlock_t                conn_lock;      /* Lock for ->conn_proc_list, ->service_conns */
        struct work_struct      service_conn_reaper;
        struct timer_list       service_conn_reap_timer;

        bool                    live;

        atomic_t                nr_client_conns;

        struct hlist_head       local_endpoints;
        struct mutex            local_mutex;    /* Lock for ->local_endpoints */

        DECLARE_HASHTABLE       (peer_hash, 10);
        spinlock_t              peer_hash_lock; /* Lock for ->peer_hash */

#define RXRPC_KEEPALIVE_TIME 20 /* NAT keepalive time in seconds */
        u8                      peer_keepalive_cursor;
        time64_t                peer_keepalive_base;
        struct list_head        peer_keepalive[32];
        struct list_head        peer_keepalive_new;
        struct timer_list       peer_keepalive_timer;
        struct work_struct      peer_keepalive_work;

        atomic_t                stat_tx_data;
        atomic_t                stat_tx_data_retrans;
        atomic_t                stat_tx_data_send;
        atomic_t                stat_tx_data_send_frag;
        atomic_t                stat_tx_data_send_fail;
        atomic_t                stat_tx_data_send_msgsize;
        atomic_t                stat_tx_data_underflow;
        atomic_t                stat_tx_data_cwnd_reset;
        atomic_t                stat_rx_data;
        atomic_t                stat_rx_data_reqack;
        atomic_t                stat_rx_data_jumbo;

        atomic_t                stat_tx_ack_fill;
        atomic_t                stat_tx_ack_send;
        atomic_t                stat_tx_ack_skip;
        atomic_t                stat_tx_acks[256];
        atomic_t                stat_rx_acks[256];
        atomic_t                stat_tx_jumbo[10];
        atomic_t                stat_rx_jumbo[10];

        atomic_t                stat_why_req_ack[8];

        atomic_t                stat_io_loop;
};

/*
 * Service backlog preallocation.
 *
 * This contains circular buffers of preallocated peers, connections and calls
 * for incoming service calls and their head and tail pointers.  This allows
 * calls to be set up in the data_ready handler, thereby avoiding the need to
 * shuffle packets around so much.
 */
struct rxrpc_backlog {
        unsigned short          peer_backlog_head;
        unsigned short          peer_backlog_tail;
        unsigned short          conn_backlog_head;
        unsigned short          conn_backlog_tail;
        unsigned short          call_backlog_head;
        unsigned short          call_backlog_tail;
#define RXRPC_BACKLOG_MAX       32
        struct rxrpc_peer       *peer_backlog[RXRPC_BACKLOG_MAX];
        struct rxrpc_connection *conn_backlog[RXRPC_BACKLOG_MAX];
        struct rxrpc_call       *call_backlog[RXRPC_BACKLOG_MAX];
};

/*
 * RxRPC socket definition
 */
struct rxrpc_sock {
        /* WARNING: sk has to be the first member */
        struct sock             sk;
        const struct rxrpc_kernel_ops *app_ops; /* Table of kernel app notification funcs */
        struct rxrpc_local      *local;         /* local endpoint */
        struct rxrpc_backlog    *backlog;       /* Preallocation for services */
        struct sk_buff_head     recvmsg_oobq;   /* OOB messages for recvmsg to pick up */
        struct rb_root          pending_oobq;   /* OOB messages awaiting userspace to respond to */
        u64                     oob_id_counter; /* OOB message ID counter */
        spinlock_t              incoming_lock;  /* Incoming call vs service shutdown lock */
        struct list_head        sock_calls;     /* List of calls owned by this socket */
        struct list_head        to_be_accepted; /* calls awaiting acceptance */
        struct list_head        recvmsg_q;      /* Calls awaiting recvmsg's attention  */
        spinlock_t              recvmsg_lock;   /* Lock for recvmsg_q */
        struct key              *key;           /* security for this socket */
        struct key              *securities;    /* list of server security descriptors */
        struct rb_root          calls;          /* User ID -> call mapping */
        unsigned long           flags;
#define RXRPC_SOCK_CONNECTED            0       /* connect_srx is set */
#define RXRPC_SOCK_MANAGE_RESPONSE      1       /* User wants to manage RESPONSE packets */
        rwlock_t                call_lock;      /* lock for calls */
        u32                     min_sec_level;  /* minimum security level */
#define RXRPC_SECURITY_MAX      RXRPC_SECURITY_ENCRYPT
        bool                    exclusive;      /* Exclusive connection for a client socket */
        u16                     second_service; /* Additional service bound to the endpoint */
        struct {
                /* Service upgrade information */
                u16             from;           /* Service ID to upgrade (if not 0) */
                u16             to;             /* service ID to upgrade to */
        } service_upgrade;
        sa_family_t             family;         /* Protocol family created with */
        struct sockaddr_rxrpc   srx;            /* Primary Service/local addresses */
        struct sockaddr_rxrpc   connect_srx;    /* Default client address from connect() */
};

#define rxrpc_sk(__sk) container_of((__sk), struct rxrpc_sock, sk)

/*
 * CPU-byteorder normalised Rx packet header.
 */
struct rxrpc_host_header {
        u32             epoch;          /* client boot timestamp */
        u32             cid;            /* connection and channel ID */
        u32             callNumber;     /* call ID (0 for connection-level packets) */
        u32             seq;            /* sequence number of pkt in call stream */
        u32             serial;         /* serial number of pkt sent to network */
        u8              type;           /* packet type */
        u8              flags;          /* packet flags */
        u8              userStatus;     /* app-layer defined status */
        u8              securityIndex;  /* security protocol ID */
        union {
                u16     _rsvd;          /* reserved */
                u16     cksum;          /* kerberos security checksum */
        };
        u16             serviceId;      /* service ID */
} __packed;

/*
 * RxRPC socket buffer private variables
 * - max 48 bytes (struct sk_buff::cb)
 */
struct rxrpc_skb_priv {
        union {
                struct rxrpc_connection *poke_conn;     /* Conn referred to (poke packet) */
                struct {
                        u16             offset;         /* Offset of data */
                        u16             len;            /* Length of data */
                        u8              flags;
#define RXRPC_RX_VERIFIED       0x01
                };
                struct {
                        rxrpc_seq_t     first_ack;      /* First packet in acks table */
                        rxrpc_seq_t     prev_ack;       /* Highest seq seen */
                        rxrpc_serial_t  acked_serial;   /* Packet in response to (or 0) */
                        u16             nr_acks;        /* Number of acks+nacks */
                        u8              reason;         /* Reason for ack */
                } ack;
                struct {
                        struct rxrpc_connection *conn;  /* Connection referred to */
                        union {
                                u32 rxkad_nonce;
                        };
                } chall;
                struct {
                        rxrpc_serial_t  challenge_serial;
                        u32             kvno;
                        u32             version;
                        u16             len;
                        u16             ticket_len;
                } resp;
        };
        struct rxrpc_host_header hdr;   /* RxRPC packet header from this packet */
};

#define rxrpc_skb(__skb) ((struct rxrpc_skb_priv *) &(__skb)->cb)

/*
 * RxRPC security module interface
 */
struct rxrpc_security {
        const char              *name;          /* name of this service */
        u8                      security_index; /* security type provided */
        u32                     no_key_abort;   /* Abort code indicating no key */

        /* Initialise a security service */
        int (*init)(void);

        /* Clean up a security service */
        void (*exit)(void);

        /* Parse the information from a server key */
        int (*preparse_server_key)(struct key_preparsed_payload *);

        /* Clean up the preparse buffer after parsing a server key */
        void (*free_preparse_server_key)(struct key_preparsed_payload *);

        /* Destroy the payload of a server key */
        void (*destroy_server_key)(struct key *);

        /* Describe a server key */
        void (*describe_server_key)(const struct key *, struct seq_file *);

        /* initialise a connection's security */
        int (*init_connection_security)(struct rxrpc_connection *,
                                        struct rxrpc_key_token *);

        /* Work out how much data we can store in a packet, given an estimate
         * of the amount of data remaining and allocate a data buffer.
         */
        struct rxrpc_txbuf *(*alloc_txbuf)(struct rxrpc_call *call, size_t remaining, gfp_t gfp);

        /* impose security on a packet */
        int (*secure_packet)(struct rxrpc_call *, struct rxrpc_txbuf *);

        /* verify the security on a received packet */
        int (*verify_packet)(struct rxrpc_call *, struct sk_buff *);

        /* Free crypto request on a call */
        void (*free_call_crypto)(struct rxrpc_call *);

        /* issue a challenge */
        int (*issue_challenge)(struct rxrpc_connection *);

        /* Validate a challenge packet */
        bool (*validate_challenge)(struct rxrpc_connection *conn,
                                   struct sk_buff *skb);

        /* Fill out the cmsg for recvmsg() to pass on a challenge to userspace.
         * The security class gets to add additional information.
         */
        int (*challenge_to_recvmsg)(struct rxrpc_connection *conn,
                                    struct sk_buff *challenge,
                                    struct msghdr *msg);

        /* Parse sendmsg() control message and respond to challenge. */
        int (*sendmsg_respond_to_challenge)(struct sk_buff *challenge,
                                            struct msghdr *msg);

        /* respond to a challenge */
        int (*respond_to_challenge)(struct rxrpc_connection *conn,
                                    struct sk_buff *challenge);

        /* verify a response */
        int (*verify_response)(struct rxrpc_connection *,
                               struct sk_buff *);

        /* clear connection security */
        void (*clear)(struct rxrpc_connection *);

        /* Default ticket -> key decoder */
        int (*default_decode_ticket)(struct rxrpc_connection *conn, struct sk_buff *skb,
                                     unsigned int ticket_offset, unsigned int ticket_len,
                                     struct key **_key);
};

/*
 * RxRPC local transport endpoint description
 * - owned by a single AF_RXRPC socket
 * - pointed to by transport socket struct sk_user_data
 */
struct rxrpc_local {
        struct rcu_head         rcu;
        atomic_t                active_users;   /* Number of users of the local endpoint */
        refcount_t              ref;            /* Number of references to the structure */
        struct net              *net;           /* The network namespace */
        struct rxrpc_net        *rxnet;         /* Our bits in the network namespace */
        struct hlist_node       link;
        struct socket           *socket;        /* my UDP socket */
        struct task_struct      *io_thread;
        struct completion       io_thread_ready; /* Indication that the I/O thread started */
        struct page_frag_cache  tx_alloc;       /* Tx control packet allocation (I/O thread only) */
        struct rxrpc_sock       *service;       /* Service(s) listening on this endpoint */
#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
        struct sk_buff_head     rx_delay_queue; /* Delay injection queue */
#endif
        struct sk_buff_head     rx_queue;       /* Received packets */
        struct list_head        conn_attend_q;  /* Conns requiring immediate attention */
        struct list_head        call_attend_q;  /* Calls requiring immediate attention */

        struct rb_root          client_bundles; /* Client connection bundles by socket params */
        spinlock_t              client_bundles_lock; /* Lock for client_bundles */
        bool                    kill_all_client_conns;
        struct list_head        idle_client_conns;
        struct timer_list       client_conn_reap_timer;
        unsigned long           client_conn_flags;
#define RXRPC_CLIENT_CONN_REAP_TIMER    0       /* The client conn reap timer expired */

        spinlock_t              lock;           /* access lock */
        rwlock_t                services_lock;  /* lock for services list */
        int                     debug_id;       /* debug ID for printks */
        bool                    dead;
        bool                    service_closed; /* Service socket closed */
        struct idr              conn_ids;       /* List of connection IDs */
        struct list_head        new_client_calls; /* Newly created client calls need connection */
        spinlock_t              client_call_lock; /* Lock for ->new_client_calls */
        struct sockaddr_rxrpc   srx;            /* local address */
        union {
                /* Provide a kvec table sufficiently large to manage either a
                 * DATA packet with a maximum set of jumbo subpackets or a PING
                 * ACK padded out to 64K with zeropages for PMTUD.
                 */
                struct kvec             kvec[1 + RXRPC_MAX_NR_JUMBO > 3 + 16 ?
                                             1 + RXRPC_MAX_NR_JUMBO : 3 + 16];
                struct bio_vec          bvec[3 + 16];
        };
};

/*
 * RxRPC remote transport endpoint definition
 * - matched by local endpoint, remote port, address and protocol type
 */
struct rxrpc_peer {
        struct rcu_head         rcu;            /* This must be first */
        refcount_t              ref;
        unsigned long           hash_key;
        struct hlist_node       hash_link;
        struct rxrpc_local      *local;
        struct hlist_head       error_targets;  /* targets for net error distribution */
        struct rb_root          service_conns;  /* Service connections */
        struct list_head        keepalive_link; /* Link in net->peer_keepalive[] */
        unsigned long           app_data;       /* Application data (e.g. afs_server) */
        unsigned int            last_tx_at;     /* Last time packet sent here (time64_t LSW) */
        seqlock_t               service_conn_lock;
        spinlock_t              lock;           /* access lock */
        int                     debug_id;       /* debug ID for printks */
        struct sockaddr_rxrpc   srx;            /* remote address */

        /* Path MTU discovery [RFC8899] */
        unsigned int            pmtud_trial;    /* Current MTU probe size */
        unsigned int            pmtud_good;     /* Largest working MTU probe we've tried */
        unsigned int            pmtud_bad;      /* Smallest non-working MTU probe we've tried */
        bool                    pmtud_lost;     /* T if MTU probe was lost */
        bool                    pmtud_probing;  /* T if we have an active probe outstanding */
        bool                    pmtud_pending;  /* T if a call to this peer should send a probe */
        u8                      pmtud_jumbo;    /* Max jumbo packets for the MTU */
        bool                    ackr_adv_pmtud; /* T if the peer advertises path-MTU */
        unsigned int            ackr_max_data;  /* Maximum data advertised by peer */
        unsigned int            if_mtu;         /* Local interface MTU (- hdrsize) for this peer */
        unsigned int            max_data;       /* Maximum packet data capacity for this peer */
        unsigned short          hdrsize;        /* header size (IP + UDP + RxRPC) */
        unsigned short          tx_seg_max;     /* Maximum number of transmissable segments */

        /* Calculated RTT cache */
        unsigned int            recent_srtt_us;
        unsigned int            recent_rto_us;

        u8                      cong_ssthresh;  /* Congestion slow-start threshold */
};

/*
 * Keys for matching a connection.
 */
struct rxrpc_conn_proto {
        union {
                struct {
                        u32     epoch;          /* epoch of this connection */
                        u32     cid;            /* connection ID */
                };
                u64             index_key;
        };
};

struct rxrpc_conn_parameters {
        struct rxrpc_local      *local;         /* Representation of local endpoint */
        struct rxrpc_peer       *peer;          /* Representation of remote endpoint */
        struct key              *key;           /* Security details */
        bool                    exclusive;      /* T if conn is exclusive */
        bool                    upgrade;        /* T if service ID can be upgraded */
        u16                     service_id;     /* Service ID for this connection */
        u32                     security_level; /* Security level selected */
};

/*
 * Call completion condition (state == RXRPC_CALL_COMPLETE).
 */
enum rxrpc_call_completion {
        RXRPC_CALL_SUCCEEDED,           /* - Normal termination */
        RXRPC_CALL_REMOTELY_ABORTED,    /* - call aborted by peer */
        RXRPC_CALL_LOCALLY_ABORTED,     /* - call aborted locally on error or close */
        RXRPC_CALL_LOCAL_ERROR,         /* - call failed due to local error */
        RXRPC_CALL_NETWORK_ERROR,       /* - call terminated by network error */
        NR__RXRPC_CALL_COMPLETIONS
};

/*
 * Bits in the connection flags.
 */
enum rxrpc_conn_flag {
        RXRPC_CONN_IN_SERVICE_CONNS,    /* Conn is in peer->service_conns */
        RXRPC_CONN_DONT_REUSE,          /* Don't reuse this connection */
        RXRPC_CONN_PROBING_FOR_UPGRADE, /* Probing for service upgrade */
        RXRPC_CONN_FINAL_ACK_0,         /* Need final ACK for channel 0 */
        RXRPC_CONN_FINAL_ACK_1,         /* Need final ACK for channel 1 */
        RXRPC_CONN_FINAL_ACK_2,         /* Need final ACK for channel 2 */
        RXRPC_CONN_FINAL_ACK_3,         /* Need final ACK for channel 3 */
};

#define RXRPC_CONN_FINAL_ACK_MASK ((1UL << RXRPC_CONN_FINAL_ACK_0) |    \
                                   (1UL << RXRPC_CONN_FINAL_ACK_1) |    \
                                   (1UL << RXRPC_CONN_FINAL_ACK_2) |    \
                                   (1UL << RXRPC_CONN_FINAL_ACK_3))

/*
 * Events that can be raised upon a connection.
 */
enum rxrpc_conn_event {
        RXRPC_CONN_EV_CHALLENGE,        /* Send challenge packet */
        RXRPC_CONN_EV_ABORT_CALLS,      /* Abort attached calls */
};

/*
 * The connection protocol state.
 */
enum rxrpc_conn_proto_state {
        RXRPC_CONN_UNUSED,              /* Connection not yet attempted */
        RXRPC_CONN_CLIENT_UNSECURED,    /* Client connection needs security init */
        RXRPC_CONN_CLIENT,              /* Client connection */
        RXRPC_CONN_SERVICE_PREALLOC,    /* Service connection preallocation */
        RXRPC_CONN_SERVICE_UNSECURED,   /* Service unsecured connection */
        RXRPC_CONN_SERVICE_CHALLENGING, /* Service challenging for security */
        RXRPC_CONN_SERVICE,             /* Service secured connection */
        RXRPC_CONN_ABORTED,             /* Conn aborted */
        RXRPC_CONN__NR_STATES
};

/*
 * RxRPC client connection bundle.
 */
struct rxrpc_bundle {
        struct rxrpc_local      *local;         /* Representation of local endpoint */
        struct rxrpc_peer       *peer;          /* Remote endpoint */
        struct key              *key;           /* Security details */
        struct list_head        proc_link;      /* Link in net->bundle_proc_list */
        const struct rxrpc_security *security;  /* applied security module */
        refcount_t              ref;
        atomic_t                active;         /* Number of active users */
        unsigned int            debug_id;
        u32                     security_level; /* Security level selected */
        u16                     service_id;     /* Service ID for this connection */
        bool                    try_upgrade;    /* True if the bundle is attempting upgrade */
        bool                    exclusive;      /* T if conn is exclusive */
        bool                    upgrade;        /* T if service ID can be upgraded */
        unsigned short          alloc_error;    /* Error from last conn allocation */
        struct rb_node          local_node;     /* Node in local->client_conns */
        struct list_head        waiting_calls;  /* Calls waiting for channels */
        unsigned long           avail_chans;    /* Mask of available channels */
        unsigned int            conn_ids[4];    /* Connection IDs. */
        struct rxrpc_connection *conns[4];      /* The connections in the bundle (max 4) */
};

/*
 * RxRPC connection definition
 * - matched by { local, peer, epoch, conn_id, direction }
 * - each connection can only handle four simultaneous calls
 */
struct rxrpc_connection {
        struct rxrpc_conn_proto proto;
        struct rxrpc_local      *local;         /* Representation of local endpoint */
        struct rxrpc_peer       *peer;          /* Remote endpoint */
        struct rxrpc_net        *rxnet;         /* Network namespace to which call belongs */
        struct key              *key;           /* Security details */
        struct list_head        attend_link;    /* Link in local->conn_attend_q */

        refcount_t              ref;
        atomic_t                active;         /* Active count for service conns */
        struct rcu_head         rcu;
        struct list_head        cache_link;

        unsigned char           act_chans;      /* Mask of active channels */
        struct rxrpc_channel {
                unsigned long           final_ack_at;   /* Time at which to issue final ACK */
                struct rxrpc_call       *call;          /* Active call */
                unsigned int            call_debug_id;  /* call->debug_id */
                u32                     call_id;        /* ID of current call */
                u32                     call_counter;   /* Call ID counter */
                u32                     last_call;      /* ID of last call */
                u8                      last_type;      /* Type of last packet */
                union {
                        u32             last_seq;
                        u32             last_abort;
                };
        } channels[RXRPC_MAXCALLS];

        struct timer_list       timer;          /* Conn event timer */
        struct work_struct      processor;      /* connection event processor */
        struct work_struct      destructor;     /* In-process-context destroyer */
        struct rxrpc_bundle     *bundle;        /* Client connection bundle */
        struct rb_node          service_node;   /* Node in peer->service_conns */
        struct list_head        proc_link;      /* link in procfs list */
        struct list_head        link;           /* link in master connection list */
        struct sk_buff_head     rx_queue;       /* received conn-level packets */
        struct page_frag_cache  tx_data_alloc;  /* Tx DATA packet allocation */
        struct mutex            tx_data_alloc_lock;

        struct mutex            security_lock;  /* Lock for security management */
        const struct rxrpc_security *security;  /* applied security module */
        union {
                struct {
                        struct crypto_sync_skcipher *cipher;    /* encryption handle */
                        struct rxrpc_crypt csum_iv;     /* packet checksum base */
                        u32     nonce;          /* response re-use preventer */
                } rxkad;
                struct {
                        struct rxgk_context *keys[4]; /* (Re-)keying buffer */
                        u64     start_time;     /* The start time for TK derivation */
                        u8      nonce[20];      /* Response re-use preventer */
                        u32     enctype;        /* Kerberos 5 encoding type */
                        u32     key_number;     /* Current key number */
                } rxgk;
        };
        rwlock_t                security_use_lock; /* Security use/modification lock */
        struct sk_buff          *tx_response;   /* Response packet to be transmitted */

        unsigned long           flags;
        unsigned long           events;
        unsigned long           idle_timestamp; /* Time at which last became idle */
        spinlock_t              state_lock;     /* state-change lock */
        enum rxrpc_conn_proto_state state;      /* current state of connection */
        enum rxrpc_call_completion completion;  /* Completion condition */
        s32                     abort_code;     /* Abort code of connection abort */
        int                     debug_id;       /* debug ID for printks */
        rxrpc_serial_t          tx_serial;      /* Outgoing packet serial number counter */
        unsigned int            hi_serial;      /* highest serial number received */
        rxrpc_serial_t          pmtud_probe;    /* Serial of MTU probe (or 0) */
        unsigned int            pmtud_call;     /* ID of call used for probe */
        u32                     service_id;     /* Service ID, possibly upgraded */
        u32                     security_level; /* Security level selected */
        u8                      security_ix;    /* security type */
        u8                      out_clientflag; /* RXRPC_CLIENT_INITIATED if we are client */
        u8                      bundle_shift;   /* Index into bundle->avail_chans */
        bool                    exclusive;      /* T if conn is exclusive */
        bool                    upgrade;        /* T if service ID can be upgraded */
        u16                     orig_service_id; /* Originally requested service ID */
        short                   error;          /* Local error code */
};

static inline bool rxrpc_to_server(const struct rxrpc_skb_priv *sp)
{
        return sp->hdr.flags & RXRPC_CLIENT_INITIATED;
}

static inline bool rxrpc_to_client(const struct rxrpc_skb_priv *sp)
{
        return !rxrpc_to_server(sp);
}

/*
 * Flags in call->flags.
 */
enum rxrpc_call_flag {
        RXRPC_CALL_RELEASED,            /* call has been released - no more message to userspace */
        RXRPC_CALL_HAS_USERID,          /* has a user ID attached */
        RXRPC_CALL_IS_SERVICE,          /* Call is service call */
        RXRPC_CALL_EXPOSED,             /* The call was exposed to the world */
        RXRPC_CALL_RX_LAST,             /* Received the last packet (at rxtx_top) */
        RXRPC_CALL_TX_LAST,             /* Last packet in Tx buffer (at rxtx_top) */
        RXRPC_CALL_TX_ALL_ACKED,        /* Last packet has been hard-acked */
        RXRPC_CALL_TX_NO_MORE,          /* No more data to transmit (MSG_MORE deasserted) */
        RXRPC_CALL_SEND_PING,           /* A ping will need to be sent */
        RXRPC_CALL_RETRANS_TIMEOUT,     /* Retransmission due to timeout occurred */
        RXRPC_CALL_BEGAN_RX_TIMER,      /* We began the expect_rx_by timer */
        RXRPC_CALL_RX_HEARD,            /* The peer responded at least once to this call */
        RXRPC_CALL_DISCONNECTED,        /* The call has been disconnected */
        RXRPC_CALL_KERNEL,              /* The call was made by the kernel */
        RXRPC_CALL_UPGRADE,             /* Service upgrade was requested for the call */
        RXRPC_CALL_EXCLUSIVE,           /* The call uses a once-only connection */
        RXRPC_CALL_RX_IS_IDLE,          /* recvmsg() is idle - send an ACK */
        RXRPC_CALL_RECVMSG_READ_ALL,    /* recvmsg() read all of the received data */
        RXRPC_CALL_CONN_CHALLENGING,    /* The connection is being challenged */
};

/*
 * Events that can be raised on a call.
 */
enum rxrpc_call_event {
        RXRPC_CALL_EV_ACK_LOST,         /* ACK may be lost, send ping */
        RXRPC_CALL_EV_INITIAL_PING,     /* Send initial ping for a new service call */
};

/*
 * The states that a call can be in.
 */
enum rxrpc_call_state {
        RXRPC_CALL_UNINITIALISED,
        RXRPC_CALL_CLIENT_AWAIT_CONN,   /* - client waiting for connection to become available */
        RXRPC_CALL_CLIENT_SEND_REQUEST, /* - client sending request phase */
        RXRPC_CALL_CLIENT_AWAIT_REPLY,  /* - client awaiting reply */
        RXRPC_CALL_CLIENT_RECV_REPLY,   /* - client receiving reply phase */
        RXRPC_CALL_SERVER_PREALLOC,     /* - service preallocation */
        RXRPC_CALL_SERVER_RECV_REQUEST, /* - server receiving request */
        RXRPC_CALL_SERVER_ACK_REQUEST,  /* - server pending ACK of request */
        RXRPC_CALL_SERVER_SEND_REPLY,   /* - server sending reply */
        RXRPC_CALL_SERVER_AWAIT_ACK,    /* - server awaiting final ACK */
        RXRPC_CALL_COMPLETE,            /* - call complete */
        NR__RXRPC_CALL_STATES
};

/*
 * Call Tx congestion management modes.
 */
enum rxrpc_ca_state {
        RXRPC_CA_SLOW_START,
        RXRPC_CA_CONGEST_AVOIDANCE,
        RXRPC_CA_PACKET_LOSS,
        RXRPC_CA_FAST_RETRANSMIT,
        NR__RXRPC_CA_STATES
} __mode(byte);

/*
 * Current purpose of call RACK timer.  According to the RACK-TLP protocol
 * [RFC8985], the transmission timer (call->rack_timo_at) may only be used for
 * one of these at once.
 */
enum rxrpc_rack_timer_mode {
        RXRPC_CALL_RACKTIMER_OFF,               /* Timer not running */
        RXRPC_CALL_RACKTIMER_RACK_REORDER,      /* RACK reordering timer */
        RXRPC_CALL_RACKTIMER_TLP_PTO,           /* TLP timeout */
        RXRPC_CALL_RACKTIMER_RTO,               /* Retransmission timeout */
} __mode(byte);

/*
 * RxRPC call definition
 * - matched by { connection, call_id }
 */
struct rxrpc_call {
        struct rcu_head         rcu;
        struct rxrpc_connection *conn;          /* connection carrying call */
        struct rxrpc_bundle     *bundle;        /* Connection bundle to use */
        struct rxrpc_peer       *peer;          /* Peer record for remote address */
        struct rxrpc_local      *local;         /* Representation of local endpoint */
        struct rxrpc_sock __rcu *socket;        /* socket responsible */
        struct rxrpc_net        *rxnet;         /* Network namespace to which call belongs */
        struct key              *key;           /* Security details */
        const struct rxrpc_security *security;  /* applied security module */
        struct mutex            user_mutex;     /* User access mutex */
        struct sockaddr_rxrpc   dest_srx;       /* Destination address */
        ktime_t                 delay_ack_at;   /* When DELAY ACK needs to happen */
        ktime_t                 rack_timo_at;   /* When ACK is figured as lost */
        ktime_t                 ping_at;        /* When next to send a ping */
        ktime_t                 keepalive_at;   /* When next to send a keepalive ping */
        ktime_t                 expect_rx_by;   /* When we expect to get a packet by */
        ktime_t                 expect_req_by;  /* When we expect to get a request DATA packet by */
        ktime_t                 expect_term_by; /* When we expect call termination by */
        u32                     next_rx_timo;   /* Timeout for next Rx packet (ms) */
        u32                     next_req_timo;  /* Timeout for next Rx request packet (ms) */
        u32                     hard_timo;      /* Maximum lifetime or 0 (s) */
        struct timer_list       timer;          /* Combined event timer */
        struct work_struct      destroyer;      /* In-process-context destroyer */
        rxrpc_notify_rx_t       notify_rx;      /* kernel service Rx notification function */
        struct list_head        link;           /* link in master call list */
        struct list_head        wait_link;      /* Link in local->new_client_calls */
        struct hlist_node       error_link;     /* link in error distribution list */
        struct list_head        accept_link;    /* Link in rx->acceptq */
        struct list_head        recvmsg_link;   /* Link in rx->recvmsg_q */
        struct list_head        sock_link;      /* Link in rx->sock_calls */
        struct rb_node          sock_node;      /* Node in rx->calls */
        struct list_head        attend_link;    /* Link in local->call_attend_q */
        struct rxrpc_txbuf      *tx_pending;    /* Tx buffer being filled */
        wait_queue_head_t       waitq;          /* Wait queue for channel or Tx */
        s64                     tx_total_len;   /* Total length left to be transmitted (or -1) */
        unsigned long           user_call_ID;   /* user-defined call ID */
        unsigned long           flags;
        unsigned long           events;
        spinlock_t              notify_lock;    /* Kernel notification lock */
        unsigned int            send_abort_why; /* Why the abort [enum rxrpc_abort_reason] */
        s32                     send_abort;     /* Abort code to be sent */
        short                   send_abort_err; /* Error to be associated with the abort */
        rxrpc_seq_t             send_abort_seq; /* DATA packet that incurred the abort (or 0) */
        s32                     abort_code;     /* Local/remote abort code */
        int                     error;          /* Local error incurred */
        enum rxrpc_call_state   _state;         /* Current state of call (needs barrier) */
        enum rxrpc_call_completion completion;  /* Call completion condition */
        refcount_t              ref;
        u8                      security_ix;    /* Security type */
        enum rxrpc_interruptibility interruptibility; /* At what point call may be interrupted */
        u32                     call_id;        /* call ID on connection  */
        u32                     cid;            /* connection ID plus channel index */
        u32                     security_level; /* Security level selected */
        u32                     security_enctype; /* Security-specific encoding type (or 0) */
        int                     debug_id;       /* debug ID for printks */
        unsigned short          rx_pkt_offset;  /* Current recvmsg packet offset */
        unsigned short          rx_pkt_len;     /* Current recvmsg packet len */

        /* Sendmsg data tracking. */
        rxrpc_seq_t             send_top;       /* Highest Tx slot filled by sendmsg. */
        struct rxrpc_txqueue    *send_queue;    /* Queue that sendmsg is writing into */

        /* Transmitted data tracking. */
        struct rxrpc_txqueue    *tx_queue;      /* Start of transmission buffers */
        struct rxrpc_txqueue    *tx_qtail;      /* End of transmission buffers */
        rxrpc_seq_t             tx_qbase;       /* First slot in tx_queue */
        rxrpc_seq_t             tx_bottom;      /* First packet in buffer */
        rxrpc_seq_t             tx_transmitted; /* Highest packet transmitted */
        rxrpc_seq_t             tx_top;         /* Highest Tx slot allocated. */
        rxrpc_serial_t          tx_last_serial; /* Serial of last DATA transmitted */
        u16                     tx_backoff;     /* Delay to insert due to Tx failure (ms) */
        u16                     tx_nr_sent;     /* Number of packets sent, but unacked */
        u16                     tx_nr_lost;     /* Number of packets marked lost */
        u16                     tx_nr_resent;   /* Number of packets resent, but unacked */
        u16                     tx_winsize;     /* Maximum size of Tx window */
#define RXRPC_TX_MAX_WINDOW     128
        u8                      tx_jumbo_max;   /* Maximum subpkts peer will accept */
        ktime_t                 tx_last_sent;   /* Last time a transmission occurred */

        /* Received data tracking */
        struct sk_buff_head     recvmsg_queue;  /* Queue of packets ready for recvmsg() */
        struct sk_buff_head     rx_queue;       /* Queue of packets for this call to receive */
        struct sk_buff_head     rx_oos_queue;   /* Queue of out of sequence packets */

        rxrpc_seq_t             rx_highest_seq; /* Higest sequence number received */
        rxrpc_seq_t             rx_consumed;    /* Highest packet consumed */
        rxrpc_serial_t          rx_serial;      /* Highest serial received for this call */
        u8                      rx_winsize;     /* Size of Rx window */

        /* TCP-style slow-start congestion control [RFC5681].  Since the SMSS
         * is fixed, we keep these numbers in terms of segments (ie. DATA
         * packets) rather than bytes.
         */
#define RXRPC_TX_SMSS           RXRPC_JUMBO_DATALEN
#define RXRPC_MIN_CWND          4
        enum rxrpc_ca_state     cong_ca_state;  /* Congestion control state */
        u8                      cong_extra;     /* Extra to send for congestion management */
        u16                     cong_cwnd;      /* Congestion window size */
        u16                     cong_ssthresh;  /* Slow-start threshold */
        u16                     cong_dup_acks;  /* Count of ACKs showing missing packets */
        u16                     cong_cumul_acks; /* Cumulative ACK count */
        ktime_t                 cong_tstamp;    /* Last time cwnd was changed */

        /* RACK-TLP [RFC8985] state. */
        ktime_t                 rack_xmit_ts;   /* Latest transmission timestamp */
        ktime_t                 rack_rtt;       /* RTT of most recently ACK'd segment */
        ktime_t                 rack_rtt_ts;    /* Timestamp of rack_rtt */
        ktime_t                 rack_reo_wnd;   /* Reordering window */
        unsigned int            rack_reo_wnd_mult; /* Multiplier applied to rack_reo_wnd */
        int                     rack_reo_wnd_persist; /* Num loss recoveries before reset reo_wnd */
        rxrpc_seq_t             rack_fack;      /* Highest sequence so far ACK'd */
        rxrpc_seq_t             rack_end_seq;   /* Highest sequence seen */
        rxrpc_seq_t             rack_dsack_round; /* DSACK opt recv'd in latest roundtrip */
        bool                    rack_dsack_round_none; /* T if dsack_round is "None" */
        bool                    rack_reordering_seen; /* T if detected reordering event */
        enum rxrpc_rack_timer_mode rack_timer_mode; /* Current mode of RACK timer */
        bool                    tlp_is_retrans; /* T if unacked TLP retransmission */
        rxrpc_serial_t          tlp_serial;     /* Serial of TLP probe (or 0 if none in progress) */
        rxrpc_seq_t             tlp_seq;        /* Sequence of TLP probe */
        unsigned int            tlp_rtt_taken;  /* Last time RTT taken */
        ktime_t                 tlp_max_ack_delay; /* Sender budget for max delayed ACK interval */

        /* Receive-phase ACK management (ACKs we send). */
        u8                      ackr_reason;    /* reason to ACK */
        u16                     ackr_sack_base; /* Starting slot in SACK table ring */
        rxrpc_seq_t             ackr_window;    /* Base of SACK window */
        rxrpc_seq_t             ackr_wtop;      /* Base of SACK window */
        unsigned int            ackr_nr_unacked; /* Number of unacked packets */
        atomic_t                ackr_nr_consumed; /* Number of packets needing hard ACK */
        struct {
#define RXRPC_SACK_SIZE 256
                 /* SACK table for soft-acked packets */
                u8              ackr_sack_table[RXRPC_SACK_SIZE];
        } __aligned(8);

        /* RTT management */
        rxrpc_serial_t          rtt_serial[4];  /* Serial number of DATA or PING sent */
        ktime_t                 rtt_sent_at[4]; /* Time packet sent */
        unsigned long           rtt_avail;      /* Mask of available slots in bits 0-3,
                                                 * Mask of pending samples in 8-11 */
#define RXRPC_CALL_RTT_AVAIL_MASK       0xf
#define RXRPC_CALL_RTT_PEND_SHIFT       8

        /* Transmission-phase ACK management (ACKs we've received). */
        ktime_t                 acks_latest_ts; /* Timestamp of latest ACK received */
        rxrpc_seq_t             acks_hard_ack;  /* Highest sequence hard acked */
        rxrpc_seq_t             acks_prev_seq;  /* Highest previousPacket received */
        rxrpc_seq_t             acks_lowest_nak; /* Lowest NACK in the buffer (or ==tx_hard_ack) */
        rxrpc_serial_t          acks_highest_serial; /* Highest serial number ACK'd */
        unsigned short          acks_nr_sacks;  /* Number of soft acks recorded */
        unsigned short          acks_nr_snacks; /* Number of soft nacks recorded */

        /* Calculated RTT cache */
        ktime_t                 rtt_last_req;   /* Time of last RTT request */
        unsigned int            rtt_count;      /* Number of samples we've got */
        unsigned int            rtt_taken;      /* Number of samples taken (wrapping) */
        struct minmax           min_rtt;        /* Estimated minimum RTT */
        u32                     srtt_us;        /* smoothed round trip time << 3 in usecs */
        u32                     mdev_us;        /* medium deviation                     */
        u32                     mdev_max_us;    /* maximal mdev for the last rtt period */
        u32                     rttvar_us;      /* smoothed mdev_max                    */
        u32                     rto_us;         /* Retransmission timeout in usec */
        u8                      backoff;        /* Backoff timeout (as shift) */
};

/*
 * Summary of a new ACK and the changes it made to the Tx buffer packet states.
 */
struct rxrpc_ack_summary {
        rxrpc_serial_t  ack_serial;             /* Serial number of ACK */
        rxrpc_serial_t  acked_serial;           /* Serial number ACK'd */
        u16             in_flight;              /* Number of unreceived transmissions */
        u16             nr_new_hacks;           /* Number of rotated new ACKs */
        u16             nr_new_sacks;           /* Number of new soft ACKs in packet */
        u16             nr_new_snacks;          /* Number of new soft nacks in packet */
        u8              ack_reason;
        bool            new_low_snack:1;        /* T if new low soft NACK found */
        bool            retrans_timeo:1;        /* T if reTx due to timeout happened */
        bool            need_retransmit:1;      /* T if we need transmission */
        bool            rtt_sample_avail:1;     /* T if RTT sample available */
        bool            in_fast_or_rto_recovery:1;
        bool            exiting_fast_or_rto_recovery:1;
        bool            tlp_probe_acked:1;      /* T if the TLP probe seq was acked */
        u8 /*enum rxrpc_congest_change*/ change;
};

/*
 * sendmsg() cmsg-specified parameters.
 */
enum rxrpc_command {
        RXRPC_CMD_SEND_DATA,            /* send data message */
        RXRPC_CMD_SEND_ABORT,           /* request abort generation */
        RXRPC_CMD_REJECT_BUSY,          /* [server] reject a call as busy */
        RXRPC_CMD_CHARGE_ACCEPT,        /* [server] charge accept preallocation */
};

struct rxrpc_call_params {
        s64                     tx_total_len;   /* Total Tx data length (if send data) */
        unsigned long           user_call_ID;   /* User's call ID */
        struct {
                u32             hard;           /* Maximum lifetime (sec) */
                u32             idle;           /* Max time since last data packet (msec) */
                u32             normal;         /* Max time since last call packet (msec) */
        } timeouts;
        u8                      nr_timeouts;    /* Number of timeouts specified */
        bool                    kernel;         /* T if kernel is making the call */
        enum rxrpc_interruptibility interruptibility; /* How is interruptible is the call? */
};

struct rxrpc_send_params {
        struct rxrpc_call_params call;
        u32                     abort_code;     /* Abort code to Tx (if abort) */
        enum rxrpc_command      command : 8;    /* The command to implement */
        bool                    exclusive;      /* Shared or exclusive call */
        bool                    upgrade;        /* If the connection is upgradeable */
};

/*
 * Buffer of data to be output as a packet.
 */
struct rxrpc_txbuf {
        refcount_t              ref;
        rxrpc_seq_t             seq;            /* Sequence number of this packet */
        rxrpc_serial_t          serial;         /* Last serial number transmitted with */
        unsigned int            call_debug_id;
        unsigned int            debug_id;
        unsigned short          len;            /* Amount of data in buffer */
        unsigned short          space;          /* Remaining data space */
        unsigned short          offset;         /* Offset of fill point */
        unsigned short          crypto_header;  /* Size of crypto header */
        unsigned short          sec_header;     /* Size of security header */
        unsigned short          pkt_len;        /* Size of packet content */
        unsigned short          alloc_size;     /* Amount of bufferage allocated */
        unsigned int            flags;
#define RXRPC_TXBUF_WIRE_FLAGS  0xff            /* The wire protocol flags */
#define RXRPC_TXBUF_RESENT      0x100           /* Set if has been resent */
        __be16                  cksum;          /* Checksum to go in header */
        bool                    jumboable;      /* Can be non-terminal jumbo subpacket */
        void                    *data;          /* Data with preceding jumbo header */
};

static inline bool rxrpc_sending_to_server(const struct rxrpc_txbuf *txb)
{
        return txb->flags & RXRPC_CLIENT_INITIATED;
}

static inline bool rxrpc_sending_to_client(const struct rxrpc_txbuf *txb)
{
        return !rxrpc_sending_to_server(txb);
}

/*
 * Transmit queue element, including RACK [RFC8985] per-segment metadata.  The
 * transmission timestamp is in usec from the base.
 */
struct rxrpc_txqueue {
        /* Start with the members we want to prefetch. */
        struct rxrpc_txqueue    *next;
        ktime_t                 xmit_ts_base;
        rxrpc_seq_t             qbase;
        u8                      nr_reported_acks; /* Number of segments explicitly acked/nacked */
        unsigned long           segment_acked;  /* Bit-per-buf: Set if ACK'd */
        unsigned long           segment_lost;   /* Bit-per-buf: Set if declared lost */
        unsigned long           segment_retransmitted; /* Bit-per-buf: Set if retransmitted */
        unsigned long           rtt_samples;    /* Bit-per-buf: Set if available for RTT */
        unsigned long           ever_retransmitted; /* Bit-per-buf: Set if ever retransmitted */

        /* The arrays we want to pack into as few cache lines as possible. */
        struct {
#define RXRPC_NR_TXQUEUE BITS_PER_LONG
#define RXRPC_TXQ_MASK (RXRPC_NR_TXQUEUE - 1)
                struct rxrpc_txbuf *bufs[RXRPC_NR_TXQUEUE];
                unsigned int    segment_serial[RXRPC_NR_TXQUEUE];
                unsigned int    segment_xmit_ts[RXRPC_NR_TXQUEUE];
        } ____cacheline_aligned;
};

/*
 * Data transmission request.
 */
struct rxrpc_send_data_req {
        ktime_t                 now;            /* Current time */
        struct rxrpc_txqueue    *tq;            /* Tx queue segment holding first DATA */
        rxrpc_seq_t             seq;            /* Sequence of first data */
        int                     n;              /* Number of DATA packets to glue into jumbo */
        bool                    retrans;        /* T if this is a retransmission */
        bool                    did_send;       /* T if did actually send */
        bool                    tlp_probe;      /* T if this is a TLP probe */
        int /* enum rxrpc_txdata_trace */ trace;
};

#include <trace/events/rxrpc.h>

/*
 * Allocate the next serial number on a connection.  0 must be skipped.
 */
static inline rxrpc_serial_t rxrpc_get_next_serial(struct rxrpc_connection *conn)
{
        rxrpc_serial_t serial;

        serial = conn->tx_serial;
        if (serial == 0)
                serial = 1;
        conn->tx_serial = serial + 1;
        return serial;
}

/*
 * Allocate the next serial n numbers on a connection.  0 must be skipped.
 */
static inline rxrpc_serial_t rxrpc_get_next_serials(struct rxrpc_connection *conn,
                                                    unsigned int n)
{
        rxrpc_serial_t serial;

        serial = conn->tx_serial;
        if (serial + n <= n)
                serial = 1;
        conn->tx_serial = serial + n;
        return serial;
}

/*
 * af_rxrpc.c
 */
extern atomic_t rxrpc_n_rx_skbs;
extern struct workqueue_struct *rxrpc_workqueue;

/*
 * call_accept.c
 */
int rxrpc_service_prealloc(struct rxrpc_sock *, gfp_t);
void rxrpc_discard_prealloc(struct rxrpc_sock *);
bool rxrpc_new_incoming_call(struct rxrpc_local *local,
                             struct rxrpc_peer *peer,
                             struct rxrpc_connection *conn,
                             struct sockaddr_rxrpc *peer_srx,
                             struct sk_buff *skb);
int rxrpc_user_charge_accept(struct rxrpc_sock *, unsigned long);

/*
 * call_event.c
 */
void rxrpc_propose_ping(struct rxrpc_call *call, u32 serial,
                        enum rxrpc_propose_ack_trace why);
void rxrpc_propose_delay_ACK(struct rxrpc_call *, rxrpc_serial_t,
                             enum rxrpc_propose_ack_trace);
void rxrpc_resend_tlp(struct rxrpc_call *call);
void rxrpc_transmit_some_data(struct rxrpc_call *call, unsigned int limit,
                              enum rxrpc_txdata_trace trace);
bool rxrpc_input_call_event(struct rxrpc_call *call);

/*
 * call_object.c
 */
extern const char *const rxrpc_call_states[];
extern const char *const rxrpc_call_completions[];
extern struct kmem_cache *rxrpc_call_jar;

void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what);
struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *, unsigned long);
struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *, gfp_t, unsigned int);
struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *,
                                         struct rxrpc_conn_parameters *,
                                         struct rxrpc_call_params *, gfp_t,
                                         unsigned int)
        __releases(&rx->sk.sk_lock)
        __acquires(&call->user_mutex);
void rxrpc_start_call_timer(struct rxrpc_call *call);
void rxrpc_incoming_call(struct rxrpc_sock *, struct rxrpc_call *,
                         struct sk_buff *);
void rxrpc_release_call(struct rxrpc_sock *, struct rxrpc_call *);
void rxrpc_release_calls_on_socket(struct rxrpc_sock *);
void rxrpc_see_call(struct rxrpc_call *, enum rxrpc_call_trace);
struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *, enum rxrpc_call_trace);
void rxrpc_get_call(struct rxrpc_call *, enum rxrpc_call_trace);
void rxrpc_put_call(struct rxrpc_call *, enum rxrpc_call_trace);
void rxrpc_cleanup_call(struct rxrpc_call *);
void rxrpc_destroy_all_calls(struct rxrpc_net *);

static inline bool rxrpc_is_service_call(const struct rxrpc_call *call)
{
        return test_bit(RXRPC_CALL_IS_SERVICE, &call->flags);
}

static inline bool rxrpc_is_client_call(const struct rxrpc_call *call)
{
        return !rxrpc_is_service_call(call);
}

/*
 * call_state.c
 */
bool rxrpc_set_call_completion(struct rxrpc_call *call,
                               enum rxrpc_call_completion compl,
                               u32 abort_code,
                               int error);
bool rxrpc_call_completed(struct rxrpc_call *call);
bool rxrpc_abort_call(struct rxrpc_call *call, rxrpc_seq_t seq,
                      u32 abort_code, int error, enum rxrpc_abort_reason why);
void rxrpc_prefail_call(struct rxrpc_call *call, enum rxrpc_call_completion compl,
                        int error);

static inline void rxrpc_set_call_state(struct rxrpc_call *call,
                                        enum rxrpc_call_state state)
{
        /* Order write of completion info before write of ->state. */
        smp_store_release(&call->_state, state);
        wake_up(&call->waitq);
}

static inline enum rxrpc_call_state __rxrpc_call_state(const struct rxrpc_call *call)
{
        return call->_state; /* Only inside I/O thread */
}

static inline bool __rxrpc_call_is_complete(const struct rxrpc_call *call)
{
        return __rxrpc_call_state(call) == RXRPC_CALL_COMPLETE;
}

static inline enum rxrpc_call_state rxrpc_call_state(const struct rxrpc_call *call)
{
        /* Order read ->state before read of completion info. */
        return smp_load_acquire(&call->_state);
}

static inline bool rxrpc_call_is_complete(const struct rxrpc_call *call)
{
        return rxrpc_call_state(call) == RXRPC_CALL_COMPLETE;
}

static inline bool rxrpc_call_has_failed(const struct rxrpc_call *call)
{
        return rxrpc_call_is_complete(call) && call->completion != RXRPC_CALL_SUCCEEDED;
}

/*
 * conn_client.c
 */
extern unsigned int rxrpc_reap_client_connections;
extern unsigned long rxrpc_conn_idle_client_expiry;
extern unsigned long rxrpc_conn_idle_client_fast_expiry;

void rxrpc_purge_client_connections(struct rxrpc_local *local);
struct rxrpc_bundle *rxrpc_get_bundle(struct rxrpc_bundle *, enum rxrpc_bundle_trace);
void rxrpc_put_bundle(struct rxrpc_bundle *, enum rxrpc_bundle_trace);
int rxrpc_look_up_bundle(struct rxrpc_call *call, gfp_t gfp);
void rxrpc_connect_client_calls(struct rxrpc_local *local);
void rxrpc_expose_client_call(struct rxrpc_call *);
void rxrpc_disconnect_client_call(struct rxrpc_bundle *, struct rxrpc_call *);
void rxrpc_deactivate_bundle(struct rxrpc_bundle *bundle);
void rxrpc_discard_expired_client_conns(struct rxrpc_local *local);
void rxrpc_clean_up_local_conns(struct rxrpc_local *);

/*
 * conn_event.c
 */
void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn, struct sk_buff *skb,
                                unsigned int channel);
int rxrpc_abort_conn(struct rxrpc_connection *conn, struct sk_buff *skb,
                     s32 abort_code, int err, enum rxrpc_abort_reason why);
void rxrpc_process_connection(struct work_struct *);
void rxrpc_process_delayed_final_acks(struct rxrpc_connection *, bool);
bool rxrpc_input_conn_packet(struct rxrpc_connection *conn, struct sk_buff *skb);
void rxrpc_input_conn_event(struct rxrpc_connection *conn, struct sk_buff *skb);

static inline bool rxrpc_is_conn_aborted(const struct rxrpc_connection *conn)
{
        /* Order reading the abort info after the state check. */
        return smp_load_acquire(&conn->state) == RXRPC_CONN_ABORTED;
}

/*
 * conn_object.c
 */
extern unsigned int rxrpc_connection_expiry;
extern unsigned int rxrpc_closed_conn_expiry;

void rxrpc_poke_conn(struct rxrpc_connection *conn, enum rxrpc_conn_trace why);
struct rxrpc_connection *rxrpc_alloc_connection(struct rxrpc_net *, gfp_t);
struct rxrpc_connection *rxrpc_find_client_connection_rcu(struct rxrpc_local *,
                                                          struct sockaddr_rxrpc *,
                                                          struct sk_buff *);
void __rxrpc_disconnect_call(struct rxrpc_connection *, struct rxrpc_call *);
void rxrpc_disconnect_call(struct rxrpc_call *);
void rxrpc_kill_client_conn(struct rxrpc_connection *);
void rxrpc_queue_conn(struct rxrpc_connection *, enum rxrpc_conn_trace);
void rxrpc_see_connection(struct rxrpc_connection *, enum rxrpc_conn_trace);
struct rxrpc_connection *rxrpc_get_connection(struct rxrpc_connection *,
                                              enum rxrpc_conn_trace);
struct rxrpc_connection *rxrpc_get_connection_maybe(struct rxrpc_connection *,
                                                    enum rxrpc_conn_trace);
void rxrpc_put_connection(struct rxrpc_connection *, enum rxrpc_conn_trace);
void rxrpc_service_connection_reaper(struct work_struct *);
void rxrpc_destroy_all_connections(struct rxrpc_net *);

static inline bool rxrpc_conn_is_client(const struct rxrpc_connection *conn)
{
        return conn->out_clientflag;
}

static inline bool rxrpc_conn_is_service(const struct rxrpc_connection *conn)
{
        return !rxrpc_conn_is_client(conn);
}

static inline void rxrpc_reduce_conn_timer(struct rxrpc_connection *conn,
                                           unsigned long expire_at)
{
        timer_reduce(&conn->timer, expire_at);
}

/*
 * conn_service.c
 */
struct rxrpc_connection *rxrpc_find_service_conn_rcu(struct rxrpc_peer *,
                                                     struct sk_buff *);
struct rxrpc_connection *rxrpc_prealloc_service_connection(struct rxrpc_net *, gfp_t);
void rxrpc_new_incoming_connection(struct rxrpc_sock *, struct rxrpc_connection *,
                                   const struct rxrpc_security *, struct sk_buff *);
void rxrpc_unpublish_service_conn(struct rxrpc_connection *);

/*
 * input.c
 */
void rxrpc_congestion_degrade(struct rxrpc_call *);
void rxrpc_input_call_packet(struct rxrpc_call *, struct sk_buff *);
void rxrpc_implicit_end_call(struct rxrpc_call *, struct sk_buff *);

/*
 * input_rack.c
 */
void rxrpc_input_rack_one(struct rxrpc_call *call,
                          struct rxrpc_ack_summary *summary,
                          struct rxrpc_txqueue *tq,
                          unsigned int ix);
void rxrpc_input_rack(struct rxrpc_call *call,
                      struct rxrpc_ack_summary *summary,
                      struct rxrpc_txqueue *tq,
                      unsigned long new_acks);
void rxrpc_rack_detect_loss_and_arm_timer(struct rxrpc_call *call,
                                          struct rxrpc_ack_summary *summary);
ktime_t rxrpc_tlp_calc_pto(struct rxrpc_call *call, ktime_t now);
void rxrpc_tlp_send_probe(struct rxrpc_call *call);
void rxrpc_tlp_process_ack(struct rxrpc_call *call, struct rxrpc_ack_summary *summary);
void rxrpc_rack_timer_expired(struct rxrpc_call *call, ktime_t overran_by);

/* Initialise TLP state [RFC8958 7.1]. */
static inline void rxrpc_tlp_init(struct rxrpc_call *call)
{
        call->tlp_serial = 0;
        call->tlp_seq = call->acks_hard_ack;
        call->tlp_is_retrans = false;
}

/*
 * io_thread.c
 */
int rxrpc_encap_rcv(struct sock *, struct sk_buff *);
void rxrpc_error_report(struct sock *);
bool rxrpc_direct_abort(struct sk_buff *skb, enum rxrpc_abort_reason why,
                        s32 abort_code, int err);
bool rxrpc_direct_conn_abort(struct sk_buff *skb, enum rxrpc_abort_reason why,
                             s32 abort_code, int err);
int rxrpc_io_thread(void *data);
void rxrpc_post_response(struct rxrpc_connection *conn, struct sk_buff *skb);
static inline void rxrpc_wake_up_io_thread(struct rxrpc_local *local)
{
        if (!local->io_thread)
                return;
        wake_up_process(READ_ONCE(local->io_thread));
}

static inline bool rxrpc_protocol_error(struct sk_buff *skb, enum rxrpc_abort_reason why)
{
        return rxrpc_direct_abort(skb, why, RX_PROTOCOL_ERROR, -EPROTO);
}

/*
 * insecure.c
 */
extern const struct rxrpc_security rxrpc_no_security;

/*
 * key.c
 */
extern struct key_type key_type_rxrpc;

int rxrpc_request_key(struct rxrpc_sock *, sockptr_t , int);
int rxrpc_get_server_data_key(struct rxrpc_connection *, const void *, time64_t,
                              u32);

/*
 * local_event.c
 */
void rxrpc_gen_version_string(void);
void rxrpc_send_version_request(struct rxrpc_local *local,
                                struct rxrpc_host_header *hdr,
                                struct sk_buff *skb);

/*
 * local_object.c
 */
void rxrpc_local_dont_fragment(const struct rxrpc_local *local, bool set);
struct rxrpc_local *rxrpc_lookup_local(struct net *, const struct sockaddr_rxrpc *);
struct rxrpc_local *rxrpc_get_local(struct rxrpc_local *, enum rxrpc_local_trace);
struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *, enum rxrpc_local_trace);
void rxrpc_put_local(struct rxrpc_local *, enum rxrpc_local_trace);
struct rxrpc_local *rxrpc_use_local(struct rxrpc_local *, enum rxrpc_local_trace);
void rxrpc_unuse_local(struct rxrpc_local *, enum rxrpc_local_trace);
void rxrpc_destroy_local(struct rxrpc_local *local);
void rxrpc_destroy_all_locals(struct rxrpc_net *);

static inline bool __rxrpc_use_local(struct rxrpc_local *local,
                                     enum rxrpc_local_trace why)
{
        int r, u;

        r = refcount_read(&local->ref);
        u = atomic_fetch_add_unless(&local->active_users, 1, 0);
        trace_rxrpc_local(local->debug_id, why, r, u);
        return u != 0;
}

static inline void rxrpc_see_local(struct rxrpc_local *local,
                                   enum rxrpc_local_trace why)
{
        int r, u;

        r = refcount_read(&local->ref);
        u = atomic_read(&local->active_users);
        trace_rxrpc_local(local->debug_id, why, r, u);
}

/*
 * misc.c
 */
extern unsigned int rxrpc_max_backlog __read_mostly;
extern unsigned long rxrpc_soft_ack_delay;
extern unsigned long rxrpc_idle_ack_delay;
extern unsigned int rxrpc_rx_window_size;
extern unsigned int rxrpc_rx_mtu;
extern unsigned int rxrpc_rx_jumbo_max;
#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
extern unsigned long rxrpc_inject_rx_delay;
#endif

/*
 * net_ns.c
 */
extern unsigned int rxrpc_net_id;
extern struct pernet_operations rxrpc_net_ops;

static inline struct rxrpc_net *rxrpc_net(struct net *net)
{
        return net_generic(net, rxrpc_net_id);
}

/*
 * out_of_band.c
 */
void rxrpc_notify_socket_oob(struct rxrpc_call *call, struct sk_buff *skb);
void rxrpc_add_pending_oob(struct rxrpc_sock *rx, struct sk_buff *skb);
int rxrpc_sendmsg_oob(struct rxrpc_sock *rx, struct msghdr *msg, size_t len);

/*
 * output.c
 */
ssize_t do_udp_sendmsg(struct socket *socket, struct msghdr *msg, size_t len);
void rxrpc_send_ACK(struct rxrpc_call *call, u8 ack_reason,
                    rxrpc_serial_t serial, enum rxrpc_propose_ack_trace why);
void rxrpc_send_probe_for_pmtud(struct rxrpc_call *call);
int rxrpc_send_abort_packet(struct rxrpc_call *);
void rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_send_data_req *req);
void rxrpc_send_conn_abort(struct rxrpc_connection *conn);
void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb);
void rxrpc_send_keepalive(struct rxrpc_peer *);
void rxrpc_send_response(struct rxrpc_connection *conn, struct sk_buff *skb);

/*
 * peer_event.c
 */
void rxrpc_input_error(struct rxrpc_local *, struct sk_buff *);
void rxrpc_peer_keepalive_worker(struct work_struct *);
void rxrpc_input_probe_for_pmtud(struct rxrpc_connection *conn, rxrpc_serial_t acked_serial,
                                 bool sendmsg_fail);

/* Update the last transmission time on a peer for keepalive purposes. */
static inline void rxrpc_peer_mark_tx(struct rxrpc_peer *peer)
{
        /* To avoid tearing on 32-bit systems, we only keep the LSW. */
        WRITE_ONCE(peer->last_tx_at, ktime_get_seconds());
}

/*
 * peer_object.c
 */
struct rxrpc_peer *rxrpc_lookup_peer_rcu(struct rxrpc_local *,
                                         const struct sockaddr_rxrpc *);
struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *local,
                                     struct sockaddr_rxrpc *srx, gfp_t gfp);
void rxrpc_assess_MTU_size(struct rxrpc_local *local, struct rxrpc_peer *peer);
struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *, gfp_t,
                                    enum rxrpc_peer_trace);
void rxrpc_new_incoming_peer(struct rxrpc_local *local, struct rxrpc_peer *peer);
void rxrpc_destroy_all_peers(struct rxrpc_net *);
struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *, enum rxrpc_peer_trace);
struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *, enum rxrpc_peer_trace);
void rxrpc_put_peer(struct rxrpc_peer *, enum rxrpc_peer_trace);

/*
 * proc.c
 */
extern const struct seq_operations rxrpc_call_seq_ops;
extern const struct seq_operations rxrpc_connection_seq_ops;
extern const struct seq_operations rxrpc_bundle_seq_ops;
extern const struct seq_operations rxrpc_peer_seq_ops;
extern const struct seq_operations rxrpc_local_seq_ops;

/*
 * recvmsg.c
 */
void rxrpc_notify_socket(struct rxrpc_call *);
int rxrpc_recvmsg(struct socket *, struct msghdr *, size_t, int);

/*
 * Abort a call due to a protocol error.
 */
static inline int rxrpc_abort_eproto(struct rxrpc_call *call,
                                     struct sk_buff *skb,
                                     s32 abort_code,
                                     enum rxrpc_abort_reason why)
{
        struct rxrpc_skb_priv *sp = rxrpc_skb(skb);

        rxrpc_abort_call(call, sp->hdr.seq, abort_code, -EPROTO, why);
        return -EPROTO;
}

/*
 * rtt.c
 */
void rxrpc_call_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why,
                        int rtt_slot,
                        rxrpc_serial_t send_serial, rxrpc_serial_t resp_serial,
                        ktime_t send_time, ktime_t resp_time);
ktime_t rxrpc_get_rto_backoff(struct rxrpc_call *call, bool retrans);
void rxrpc_call_init_rtt(struct rxrpc_call *call);

/*
 * rxgk.c
 */
extern const struct rxrpc_security rxgk_yfs;

/*
 * rxkad.c
 */
#ifdef CONFIG_RXKAD
extern const struct rxrpc_security rxkad;
#endif

/*
 * security.c
 */
int __init rxrpc_init_security(void);
const struct rxrpc_security *rxrpc_security_lookup(u8);
void rxrpc_exit_security(void);
int rxrpc_init_client_call_security(struct rxrpc_call *);
int rxrpc_init_client_conn_security(struct rxrpc_connection *);
const struct rxrpc_security *rxrpc_get_incoming_security(struct rxrpc_sock *,
                                                         struct sk_buff *);
struct key *rxrpc_look_up_server_security(struct rxrpc_connection *,
                                          struct sk_buff *, u32, u32);

/*
 * sendmsg.c
 */
bool rxrpc_propose_abort(struct rxrpc_call *call, s32 abort_code, int error,
                         enum rxrpc_abort_reason why);
int rxrpc_do_sendmsg(struct rxrpc_sock *, struct msghdr *, size_t);

/*
 * server_key.c
 */
extern struct key_type key_type_rxrpc_s;

int rxrpc_server_keyring(struct rxrpc_sock *, sockptr_t, int);

/*
 * skbuff.c
 */
void rxrpc_kernel_data_consumed(struct rxrpc_call *, struct sk_buff *);
void rxrpc_new_skb(struct sk_buff *, enum rxrpc_skb_trace);
void rxrpc_see_skb(struct sk_buff *, enum rxrpc_skb_trace);
void rxrpc_eaten_skb(struct sk_buff *, enum rxrpc_skb_trace);
void rxrpc_get_skb(struct sk_buff *, enum rxrpc_skb_trace);
void rxrpc_free_skb(struct sk_buff *, enum rxrpc_skb_trace);
void rxrpc_purge_queue(struct sk_buff_head *);

/*
 * stats.c
 */
int rxrpc_stats_show(struct seq_file *seq, void *v);
int rxrpc_stats_clear(struct file *file, char *buf, size_t size);

#define rxrpc_inc_stat(rxnet, s) atomic_inc(&(rxnet)->s)
#define rxrpc_dec_stat(rxnet, s) atomic_dec(&(rxnet)->s)

/*
 * sysctl.c
 */
#ifdef CONFIG_SYSCTL
extern int __init rxrpc_sysctl_init(void);
extern void rxrpc_sysctl_exit(void);
#else
static inline int __init rxrpc_sysctl_init(void) { return 0; }
static inline void rxrpc_sysctl_exit(void) {}
#endif

/*
 * txbuf.c
 */
extern atomic_t rxrpc_nr_txbuf;
struct rxrpc_txbuf *rxrpc_alloc_data_txbuf(struct rxrpc_call *call, size_t data_size,
                                           size_t data_align, gfp_t gfp);
void rxrpc_see_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what);
void rxrpc_put_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what);

/*
 * utils.c
 */
int rxrpc_extract_addr_from_skb(struct sockaddr_rxrpc *, struct sk_buff *);

static inline bool before(u32 seq1, u32 seq2)
{
        return (s32)(seq1 - seq2) < 0;
}
static inline bool before_eq(u32 seq1, u32 seq2)
{
        return (s32)(seq1 - seq2) <= 0;
}
static inline bool after(u32 seq1, u32 seq2)
{
        return (s32)(seq1 - seq2) > 0;
}
static inline bool after_eq(u32 seq1, u32 seq2)
{
        return (s32)(seq1 - seq2) >= 0;
}

static inline u32 earliest(u32 seq1, u32 seq2)
{
        return before(seq1, seq2) ? seq1 : seq2;
}

static inline u32 latest(u32 seq1, u32 seq2)
{
        return after(seq1, seq2) ? seq1 : seq2;
}

static inline bool rxrpc_seq_in_txq(const struct rxrpc_txqueue *tq, rxrpc_seq_t seq)
{
        return (seq & (RXRPC_NR_TXQUEUE - 1)) == tq->qbase;
}

static inline void rxrpc_queue_rx_call_packet(struct rxrpc_call *call, struct sk_buff *skb)
{
        rxrpc_get_skb(skb, rxrpc_skb_get_call_rx);
        __skb_queue_tail(&call->rx_queue, skb);
        rxrpc_poke_call(call, rxrpc_call_poke_rx_packet);
}

/*
 * Calculate how much space there is for transmitting more DATA packets.
 */
static inline unsigned int rxrpc_tx_window_space(const struct rxrpc_call *call)
{
        int winsize = umin(call->tx_winsize, call->cong_cwnd + call->cong_extra);
        int transmitted = call->tx_top - call->tx_bottom;

        return max(winsize - transmitted, 0);
}

static inline unsigned int rxrpc_left_out(const struct rxrpc_call *call)
{
        return call->acks_nr_sacks + call->tx_nr_lost;
}

/*
 * Calculate the number of transmitted DATA packets assumed to be in flight
 * [approx RFC6675].
 */
static inline unsigned int rxrpc_tx_in_flight(const struct rxrpc_call *call)
{
        return call->tx_nr_sent - rxrpc_left_out(call) + call->tx_nr_resent;
}

/*
 * debug tracing
 */
extern unsigned int rxrpc_debug;

#define dbgprintk(FMT,...) \
        printk("[%-6.6s] "FMT"\n", current->comm ,##__VA_ARGS__)

#define kenter(FMT,...) dbgprintk("==> %s("FMT")",__func__ ,##__VA_ARGS__)
#define kleave(FMT,...) dbgprintk("<== %s()"FMT"",__func__ ,##__VA_ARGS__)
#define kdebug(FMT,...) dbgprintk("    "FMT ,##__VA_ARGS__)


#if defined(__KDEBUG)
#define _enter(FMT,...) kenter(FMT,##__VA_ARGS__)
#define _leave(FMT,...) kleave(FMT,##__VA_ARGS__)
#define _debug(FMT,...) kdebug(FMT,##__VA_ARGS__)

#elif defined(CONFIG_AF_RXRPC_DEBUG)
#define RXRPC_DEBUG_KENTER      0x01
#define RXRPC_DEBUG_KLEAVE      0x02
#define RXRPC_DEBUG_KDEBUG      0x04

#define _enter(FMT,...)                                 \
do {                                                    \
        if (unlikely(rxrpc_debug & RXRPC_DEBUG_KENTER)) \
                kenter(FMT,##__VA_ARGS__);              \
} while (0)

#define _leave(FMT,...)                                 \
do {                                                    \
        if (unlikely(rxrpc_debug & RXRPC_DEBUG_KLEAVE)) \
                kleave(FMT,##__VA_ARGS__);              \
} while (0)

#define _debug(FMT,...)                                 \
do {                                                    \
        if (unlikely(rxrpc_debug & RXRPC_DEBUG_KDEBUG)) \
                kdebug(FMT,##__VA_ARGS__);              \
} while (0)

#else
#define _enter(FMT,...) no_printk("==> %s("FMT")",__func__ ,##__VA_ARGS__)
#define _leave(FMT,...) no_printk("<== %s()"FMT"",__func__ ,##__VA_ARGS__)
#define _debug(FMT,...) no_printk("    "FMT ,##__VA_ARGS__)
#endif

/*
 * debug assertion checking
 */
#if 1 // defined(__KDEBUGALL)

#define ASSERT(X)                                               \
do {                                                            \
        if (unlikely(!(X))) {                                   \
                pr_err("Assertion failed\n");                   \
                BUG();                                          \
        }                                                       \
} while (0)

#define ASSERTCMP(X, OP, Y)                                             \
do {                                                                    \
        __typeof__(X) _x = (X);                                         \
        __typeof__(Y) _y = (__typeof__(X))(Y);                          \
        if (unlikely(!(_x OP _y))) {                                    \
                pr_err("Assertion failed - %lu(0x%lx) %s %lu(0x%lx) is false\n", \
                       (unsigned long)_x, (unsigned long)_x, #OP,       \
                       (unsigned long)_y, (unsigned long)_y);           \
                BUG();                                                  \
        }                                                               \
} while (0)

#define ASSERTIF(C, X)                                          \
do {                                                            \
        if (unlikely((C) && !(X))) {                            \
                pr_err("Assertion failed\n");                   \
                BUG();                                          \
        }                                                       \
} while (0)

#define ASSERTIFCMP(C, X, OP, Y)                                        \
do {                                                                    \
        __typeof__(X) _x = (X);                                         \
        __typeof__(Y) _y = (__typeof__(X))(Y);                          \
        if (unlikely((C) && !(_x OP _y))) {                             \
                pr_err("Assertion failed - %lu(0x%lx) %s %lu(0x%lx) is false\n", \
                       (unsigned long)_x, (unsigned long)_x, #OP,       \
                       (unsigned long)_y, (unsigned long)_y);           \
                BUG();                                                  \
        }                                                               \
} while (0)

#else

#define ASSERT(X)                               \
do {                                            \
} while (0)

#define ASSERTCMP(X, OP, Y)                     \
do {                                            \
} while (0)

#define ASSERTIF(C, X)                          \
do {                                            \
} while (0)

#define ASSERTIFCMP(C, X, OP, Y)                \
do {                                            \
} while (0)

#endif /* __KDEBUGALL */