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Diffstat (limited to 'ipc/kdbus/connection.h')
| -rw-r--r-- | ipc/kdbus/connection.h | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/ipc/kdbus/connection.h b/ipc/kdbus/connection.h new file mode 100644 index 00000000000..d1ffe909cb3 --- /dev/null +++ b/ipc/kdbus/connection.h @@ -0,0 +1,257 @@ +/* + * Copyright (C) 2013-2015 Kay Sievers + * Copyright (C) 2013-2015 Greg Kroah-Hartman <gregkh@linuxfoundation.org> + * Copyright (C) 2013-2015 Daniel Mack <daniel@zonque.org> + * Copyright (C) 2013-2015 David Herrmann <dh.herrmann@gmail.com> + * Copyright (C) 2013-2015 Linux Foundation + * Copyright (C) 2014-2015 Djalal Harouni + * + * kdbus is free software; you can redistribute it and/or modify it under + * the terms of the GNU Lesser General Public License as published by the + * Free Software Foundation; either version 2.1 of the License, or (at + * your option) any later version. + */ + +#ifndef __KDBUS_CONNECTION_H +#define __KDBUS_CONNECTION_H + +#include <linux/atomic.h> +#include <linux/kref.h> +#include <linux/lockdep.h> +#include <linux/path.h> + +#include "limits.h" +#include "metadata.h" +#include "pool.h" +#include "queue.h" +#include "util.h" + +#define KDBUS_HELLO_SPECIAL_CONN (KDBUS_HELLO_ACTIVATOR | \ + KDBUS_HELLO_POLICY_HOLDER | \ + KDBUS_HELLO_MONITOR) + +struct kdbus_quota; +struct kdbus_kmsg; + +/** + * struct kdbus_conn - connection to a bus + * @kref: Reference count + * @active: Active references to the connection + * @id: Connection ID + * @flags: KDBUS_HELLO_* flags + * @attach_flags_send: KDBUS_ATTACH_* flags for sending + * @attach_flags_recv: KDBUS_ATTACH_* flags for receiving + * @description: Human-readable connection description, used for + * debugging. This field is only set when the + * connection is created. + * @ep: The endpoint this connection belongs to + * @lock: Connection data lock + * @hentry: Entry in ID <-> connection map + * @ep_entry: Entry in endpoint + * @monitor_entry: Entry in monitor, if the connection is a monitor + * @reply_list: List of connections this connection should + * reply to + * @work: Delayed work to handle timeouts + * activator for + * @match_db: Subscription filter to broadcast messages + * @meta: Active connection creator's metadata/credentials, + * either from the handle or from HELLO + * @pool: The user's buffer to receive messages + * @user: Owner of the connection + * @cred: The credentials of the connection at creation time + * @name_count: Number of owned well-known names + * @request_count: Number of pending requests issued by this + * connection that are waiting for replies from + * other peers + * @lost_count: Number of lost broadcast messages + * @wait: Wake up this endpoint + * @queue: The message queue associated with this connection + * @quota: Array of per-user quota indexed by user->id + * @n_quota: Number of elements in quota array + * @activator_of: Well-known name entry this connection acts as an + * @names_list: List of well-known names + * @names_queue_list: Well-known names this connection waits for + * @privileged: Whether this connection is privileged on the bus + * @faked_meta: Whether the metadata was faked on HELLO + */ +struct kdbus_conn { + struct kref kref; + atomic_t active; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif + u64 id; + u64 flags; + atomic64_t attach_flags_send; + atomic64_t attach_flags_recv; + const char *description; + struct kdbus_ep *ep; + struct mutex lock; + struct hlist_node hentry; + struct list_head ep_entry; + struct list_head monitor_entry; + struct list_head reply_list; + struct delayed_work work; + struct kdbus_match_db *match_db; + struct kdbus_meta_proc *meta; + struct kdbus_pool *pool; + struct kdbus_user *user; + const struct cred *cred; + atomic_t name_count; + atomic_t request_count; + atomic_t lost_count; + wait_queue_head_t wait; + struct kdbus_queue queue; + + struct kdbus_quota *quota; + unsigned int n_quota; + + /* protected by registry->rwlock */ + struct kdbus_name_entry *activator_of; + struct list_head names_list; + struct list_head names_queue_list; + + bool privileged:1; + bool faked_meta:1; +}; + +struct kdbus_conn *kdbus_conn_ref(struct kdbus_conn *conn); +struct kdbus_conn *kdbus_conn_unref(struct kdbus_conn *conn); +bool kdbus_conn_active(const struct kdbus_conn *conn); +int kdbus_conn_acquire(struct kdbus_conn *conn); +void kdbus_conn_release(struct kdbus_conn *conn); +int kdbus_conn_disconnect(struct kdbus_conn *conn, bool ensure_queue_empty); +bool kdbus_conn_has_name(struct kdbus_conn *conn, const char *name); +int kdbus_conn_quota_inc(struct kdbus_conn *c, struct kdbus_user *u, + size_t memory, size_t fds); +void kdbus_conn_quota_dec(struct kdbus_conn *c, struct kdbus_user *u, + size_t memory, size_t fds); +void kdbus_conn_lost_message(struct kdbus_conn *c); +int kdbus_conn_entry_insert(struct kdbus_conn *conn_src, + struct kdbus_conn *conn_dst, + const struct kdbus_kmsg *kmsg, + struct kdbus_reply *reply); +void kdbus_conn_move_messages(struct kdbus_conn *conn_dst, + struct kdbus_conn *conn_src, + u64 name_id); + +/* policy */ +bool kdbus_conn_policy_own_name(struct kdbus_conn *conn, + const struct cred *conn_creds, + const char *name); +bool kdbus_conn_policy_talk(struct kdbus_conn *conn, + const struct cred *conn_creds, + struct kdbus_conn *to); +bool kdbus_conn_policy_see_name_unlocked(struct kdbus_conn *conn, + const struct cred *curr_creds, + const char *name); +bool kdbus_conn_policy_see_notification(struct kdbus_conn *conn, + const struct cred *curr_creds, + const struct kdbus_kmsg *kmsg); + +/* command dispatcher */ +struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, bool privileged, + void __user *argp); +int kdbus_cmd_byebye_unlocked(struct kdbus_conn *conn, void __user *argp); +int kdbus_cmd_conn_info(struct kdbus_conn *conn, void __user *argp); +int kdbus_cmd_update(struct kdbus_conn *conn, void __user *argp); +int kdbus_cmd_send(struct kdbus_conn *conn, struct file *f, void __user *argp); +int kdbus_cmd_recv(struct kdbus_conn *conn, void __user *argp); +int kdbus_cmd_free(struct kdbus_conn *conn, void __user *argp); + +/** + * kdbus_conn_is_ordinary() - Check if connection is ordinary + * @conn: The connection to check + * + * Return: Non-zero if the connection is an ordinary connection + */ +static inline int kdbus_conn_is_ordinary(const struct kdbus_conn *conn) +{ + return !(conn->flags & KDBUS_HELLO_SPECIAL_CONN); +} + +/** + * kdbus_conn_is_activator() - Check if connection is an activator + * @conn: The connection to check + * + * Return: Non-zero if the connection is an activator + */ +static inline int kdbus_conn_is_activator(const struct kdbus_conn *conn) +{ + return conn->flags & KDBUS_HELLO_ACTIVATOR; +} + +/** + * kdbus_conn_is_policy_holder() - Check if connection is a policy holder + * @conn: The connection to check + * + * Return: Non-zero if the connection is a policy holder + */ +static inline int kdbus_conn_is_policy_holder(const struct kdbus_conn *conn) +{ + return conn->flags & KDBUS_HELLO_POLICY_HOLDER; +} + +/** + * kdbus_conn_is_monitor() - Check if connection is a monitor + * @conn: The connection to check + * + * Return: Non-zero if the connection is a monitor + */ +static inline int kdbus_conn_is_monitor(const struct kdbus_conn *conn) +{ + return conn->flags & KDBUS_HELLO_MONITOR; +} + +/** + * kdbus_conn_lock2() - Lock two connections + * @a: connection A to lock or NULL + * @b: connection B to lock or NULL + * + * Lock two connections at once. As we need to have a stable locking order, we + * always lock the connection with lower memory address first. + */ +static inline void kdbus_conn_lock2(struct kdbus_conn *a, struct kdbus_conn *b) +{ + if (a < b) { + if (a) + mutex_lock(&a->lock); + if (b && b != a) + mutex_lock_nested(&b->lock, !!a); + } else { + if (b) + mutex_lock(&b->lock); + if (a && a != b) + mutex_lock_nested(&a->lock, !!b); + } +} + +/** + * kdbus_conn_unlock2() - Unlock two connections + * @a: connection A to unlock or NULL + * @b: connection B to unlock or NULL + * + * Unlock two connections at once. See kdbus_conn_lock2(). + */ +static inline void kdbus_conn_unlock2(struct kdbus_conn *a, + struct kdbus_conn *b) +{ + if (a) + mutex_unlock(&a->lock); + if (b && b != a) + mutex_unlock(&b->lock); +} + +/** + * kdbus_conn_assert_active() - lockdep assert on active lock + * @conn: connection that shall be active + * + * This verifies via lockdep that the caller holds an active reference to the + * given connection. + */ +static inline void kdbus_conn_assert_active(struct kdbus_conn *conn) +{ + lockdep_assert_held(conn); +} + +#endif |