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#ifndef __FS_CEPH_MESSENGER_H
#define __FS_CEPH_MESSENGER_H

#include <linux/bvec.h>
#include <linux/crypto.h>
#include <linux/kref.h>
#include <linux/mutex.h>
#include <linux/net.h>
#include <linux/radix-tree.h>
#include <linux/uio.h>
#include <linux/workqueue.h>
#include <net/net_namespace.h>

#include <linux/ceph/types.h>
#include <linux/ceph/buffer.h>

struct ceph_msg;
struct ceph_connection;
struct ceph_msg_data_cursor;

/*
 * Ceph defines these callbacks for handling connection events.
 */
struct ceph_connection_operations {
	struct ceph_connection *(*get)(struct ceph_connection *);
	void (*put)(struct ceph_connection *);

	/* handle an incoming message. */
	void (*dispatch) (struct ceph_connection *con, struct ceph_msg *m);

	/* authorize an outgoing connection */
	struct ceph_auth_handshake *(*get_authorizer) (
				struct ceph_connection *con,
			       int *proto, int force_new);
	int (*add_authorizer_challenge)(struct ceph_connection *con,
					void *challenge_buf,
					int challenge_buf_len);
	int (*verify_authorizer_reply) (struct ceph_connection *con);
	int (*invalidate_authorizer)(struct ceph_connection *con);

	/* there was some error on the socket (disconnect, whatever) */
	void (*fault) (struct ceph_connection *con);

	/* a remote host as terminated a message exchange session, and messages
	 * we sent (or they tried to send us) may be lost. */
	void (*peer_reset) (struct ceph_connection *con);

	struct ceph_msg * (*alloc_msg) (struct ceph_connection *con,
					struct ceph_msg_header *hdr,
					int *skip);

	void (*reencode_message) (struct ceph_msg *msg);

	int (*sign_message) (struct ceph_msg *msg);
	int (*check_message_signature) (struct ceph_msg *msg);

	/* msgr2 authentication exchange */
	int (*get_auth_request)(struct ceph_connection *con,
				void *buf, int *buf_len,
				void **authorizer, int *authorizer_len);
	int (*handle_auth_reply_more)(struct ceph_connection *con,
				      void *reply, int reply_len,
				      void *buf, int *buf_len,
				      void **authorizer, int *authorizer_len);
	int (*handle_auth_done)(struct ceph_connection *con,
				u64 global_id, void *reply, int reply_len,
				u8 *session_key, int *session_key_len,
				u8 *con_secret, int *con_secret_len);
	int (*handle_auth_bad_method)(struct ceph_connection *con,
				      int used_proto, int result,
				      const int *allowed_protos, int proto_cnt,
				      const int *allowed_modes, int mode_cnt);

	/**
	 * sparse_read: read sparse data
	 * @con: connection we're reading from
	 * @cursor: data cursor for reading extents
	 * @buf: optional buffer to read into
	 *
	 * This should be called more than once, each time setting up to
	 * receive an extent into the current cursor position, and zeroing
	 * the holes between them.
	 *
	 * Returns amount of data to be read (in bytes), 0 if reading is
	 * complete, or -errno if there was an error.
	 *
	 * If @buf is set on a >0 return, then the data should be read into
	 * the provided buffer. Otherwise, it should be read into the cursor.
	 *
	 * The sparse read operation is expected to initialize the cursor
	 * with a length covering up to the end of the last extent.
	 */
	int (*sparse_read)(struct ceph_connection *con,
			   struct ceph_msg_data_cursor *cursor,
			   char **buf);

};

/* use format string %s%lld */
#define ENTITY_NAME(n) ceph_entity_type_name((n).type), le64_to_cpu((n).num)

struct ceph_messenger {
	struct ceph_entity_inst inst;    /* my name+address */
	struct ceph_entity_addr my_enc_addr;

	atomic_t stopping;
	possible_net_t net;

	/*
	 * the global_seq counts connections i (attempt to) initiate
	 * in order to disambiguate certain connect race conditions.
	 */
	u32 global_seq;
	spinlock_t global_seq_lock;
};

enum ceph_msg_data_type {
	CEPH_MSG_DATA_NONE,	/* message contains no data payload */
	CEPH_MSG_DATA_PAGES,	/* data source/destination is a page array */
	CEPH_MSG_DATA_PAGELIST,	/* data source/destination is a pagelist */
#ifdef CONFIG_BLOCK
	CEPH_MSG_DATA_BIO,	/* data source/destinatio