linux/net/tipc/msg.h
Erik Hugne 40ba3cdf54 tipc: message reassembly using fragment chain
When the first fragment of a long data data message is received on a link, a
reassembly buffer large enough to hold the data from this and all subsequent
fragments of the message is allocated. The payload of each new fragment is
copied into this buffer upon arrival. When the last fragment is received, the
reassembled message is delivered upwards to the port/socket layer.

Not only is this an inefficient approach, but it may also cause bursts of
reassembly failures in low memory situations. since we may fail to allocate
the necessary large buffer in the first place. Furthermore, after 100 subsequent
such failures the link will be reset, something that in reality aggravates the
situation.

To remedy this problem, this patch introduces a different approach. Instead of
allocating a big reassembly buffer, we now append the arriving fragments
to a reassembly chain on the link, and deliver the whole chain up to the
socket layer once the last fragment has been received. This is safe because
the retransmission layer of a TIPC link always delivers packets in strict
uninterrupted order, to the reassembly layer as to all other upper layers.
Hence there can never be more than one fragment chain pending reassembly at
any given time in a link, and we can trust (but still verify) that the
fragments will be chained up in the correct order.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-07 18:30:11 -05:00

714 lines
14 KiB
C

/*
* net/tipc/msg.h: Include file for TIPC message header routines
*
* Copyright (c) 2000-2007, Ericsson AB
* Copyright (c) 2005-2008, 2010-2011, Wind River Systems
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _TIPC_MSG_H
#define _TIPC_MSG_H
#include "bearer.h"
/*
* Constants and routines used to read and write TIPC payload message headers
*
* Note: Some items are also used with TIPC internal message headers
*/
#define TIPC_VERSION 2
/*
* Payload message users are defined in TIPC's public API:
* - TIPC_LOW_IMPORTANCE
* - TIPC_MEDIUM_IMPORTANCE
* - TIPC_HIGH_IMPORTANCE
* - TIPC_CRITICAL_IMPORTANCE
*/
/*
* Payload message types
*/
#define TIPC_CONN_MSG 0
#define TIPC_MCAST_MSG 1
#define TIPC_NAMED_MSG 2
#define TIPC_DIRECT_MSG 3
/*
* Message header sizes
*/
#define SHORT_H_SIZE 24 /* In-cluster basic payload message */
#define BASIC_H_SIZE 32 /* Basic payload message */
#define NAMED_H_SIZE 40 /* Named payload message */
#define MCAST_H_SIZE 44 /* Multicast payload message */
#define INT_H_SIZE 40 /* Internal messages */
#define MIN_H_SIZE 24 /* Smallest legal TIPC header size */
#define MAX_H_SIZE 60 /* Largest possible TIPC header size */
#define MAX_MSG_SIZE (MAX_H_SIZE + TIPC_MAX_USER_MSG_SIZE)
#define TIPC_MEDIA_ADDR_OFFSET 5
struct tipc_msg {
__be32 hdr[15];
};
static inline u32 msg_word(struct tipc_msg *m, u32 pos)
{
return ntohl(m->hdr[pos]);
}
static inline void msg_set_word(struct tipc_msg *m, u32 w, u32 val)
{
m->hdr[w] = htonl(val);
}
static inline u32 msg_bits(struct tipc_msg *m, u32 w, u32 pos, u32 mask)
{
return (msg_word(m, w) >> pos) & mask;
}
static inline void msg_set_bits(struct tipc_msg *m, u32 w,
u32 pos, u32 mask, u32 val)
{
val = (val & mask) << pos;
mask = mask << pos;
m->hdr[w] &= ~htonl(mask);
m->hdr[w] |= htonl(val);
}
static inline void msg_swap_words(struct tipc_msg *msg, u32 a, u32 b)
{
u32 temp = msg->hdr[a];
msg->hdr[a] = msg->hdr[b];
msg->hdr[b] = temp;
}
/*
* Word 0
*/
static inline u32 msg_version(struct tipc_msg *m)
{
return msg_bits(m, 0, 29, 7);
}
static inline void msg_set_version(struct tipc_msg *m)
{
msg_set_bits(m, 0, 29, 7, TIPC_VERSION);
}
static inline u32 msg_user(struct tipc_msg *m)
{
return msg_bits(m, 0, 25, 0xf);
}
static inline u32 msg_isdata(struct tipc_msg *m)
{
return msg_user(m) <= TIPC_CRITICAL_IMPORTANCE;
}
static inline void msg_set_user(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 0, 25, 0xf, n);
}
static inline u32 msg_importance(struct tipc_msg *m)
{
return msg_bits(m, 0, 25, 0xf);
}
static inline void msg_set_importance(struct tipc_msg *m, u32 i)
{
msg_set_user(m, i);
}
static inline u32 msg_hdr_sz(struct tipc_msg *m)
{
return msg_bits(m, 0, 21, 0xf) << 2;
}
static inline void msg_set_hdr_sz(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 0, 21, 0xf, n>>2);
}
static inline u32 msg_size(struct tipc_msg *m)
{
return msg_bits(m, 0, 0, 0x1ffff);
}
static inline u32 msg_data_sz(struct tipc_msg *m)
{
return msg_size(m) - msg_hdr_sz(m);
}
static inline int msg_non_seq(struct tipc_msg *m)
{
return msg_bits(m, 0, 20, 1);
}
static inline void msg_set_non_seq(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 0, 20, 1, n);
}
static inline int msg_dest_droppable(struct tipc_msg *m)
{
return msg_bits(m, 0, 19, 1);
}
static inline void msg_set_dest_droppable(struct tipc_msg *m, u32 d)
{
msg_set_bits(m, 0, 19, 1, d);
}
static inline int msg_src_droppable(struct tipc_msg *m)
{
return msg_bits(m, 0, 18, 1);
}
static inline void msg_set_src_droppable(struct tipc_msg *m, u32 d)
{
msg_set_bits(m, 0, 18, 1, d);
}
static inline void msg_set_size(struct tipc_msg *m, u32 sz)
{
m->hdr[0] = htonl((msg_word(m, 0) & ~0x1ffff) | sz);
}
/*
* Word 1
*/
static inline u32 msg_type(struct tipc_msg *m)
{
return msg_bits(m, 1, 29, 0x7);
}
static inline void msg_set_type(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 29, 0x7, n);
}
static inline u32 msg_named(struct tipc_msg *m)
{
return msg_type(m) == TIPC_NAMED_MSG;
}
static inline u32 msg_mcast(struct tipc_msg *m)
{
return msg_type(m) == TIPC_MCAST_MSG;
}
static inline u32 msg_connected(struct tipc_msg *m)
{
return msg_type(m) == TIPC_CONN_MSG;
}
static inline u32 msg_errcode(struct tipc_msg *m)
{
return msg_bits(m, 1, 25, 0xf);
}
static inline void msg_set_errcode(struct tipc_msg *m, u32 err)
{
msg_set_bits(m, 1, 25, 0xf, err);
}
static inline u32 msg_reroute_cnt(struct tipc_msg *m)
{
return msg_bits(m, 1, 21, 0xf);
}
static inline void msg_incr_reroute_cnt(struct tipc_msg *m)
{
msg_set_bits(m, 1, 21, 0xf, msg_reroute_cnt(m) + 1);
}
static inline void msg_reset_reroute_cnt(struct tipc_msg *m)
{
msg_set_bits(m, 1, 21, 0xf, 0);
}
static inline u32 msg_lookup_scope(struct tipc_msg *m)
{
return msg_bits(m, 1, 19, 0x3);
}
static inline void msg_set_lookup_scope(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 19, 0x3, n);
}
static inline u32 msg_bcast_ack(struct tipc_msg *m)
{
return msg_bits(m, 1, 0, 0xffff);
}
static inline void msg_set_bcast_ack(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 0, 0xffff, n);
}
/*
* Word 2
*/
static inline u32 msg_ack(struct tipc_msg *m)
{
return msg_bits(m, 2, 16, 0xffff);
}
static inline void msg_set_ack(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 2, 16, 0xffff, n);
}
static inline u32 msg_seqno(struct tipc_msg *m)
{
return msg_bits(m, 2, 0, 0xffff);
}
static inline void msg_set_seqno(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 2, 0, 0xffff, n);
}
/*
* Words 3-10
*/
static inline u32 msg_prevnode(struct tipc_msg *m)
{
return msg_word(m, 3);
}
static inline void msg_set_prevnode(struct tipc_msg *m, u32 a)
{
msg_set_word(m, 3, a);
}
static inline u32 msg_origport(struct tipc_msg *m)
{
return msg_word(m, 4);
}
static inline void msg_set_origport(struct tipc_msg *m, u32 p)
{
msg_set_word(m, 4, p);
}
static inline u32 msg_destport(struct tipc_msg *m)
{
return msg_word(m, 5);
}
static inline void msg_set_destport(struct tipc_msg *m, u32 p)
{
msg_set_word(m, 5, p);
}
static inline u32 msg_mc_netid(struct tipc_msg *m)
{
return msg_word(m, 5);
}
static inline void msg_set_mc_netid(struct tipc_msg *m, u32 p)
{
msg_set_word(m, 5, p);
}
static inline int msg_short(struct tipc_msg *m)
{
return msg_hdr_sz(m) == SHORT_H_SIZE;
}
static inline u32 msg_orignode(struct tipc_msg *m)
{
if (likely(msg_short(m)))
return msg_prevnode(m);
return msg_word(m, 6);
}
static inline void msg_set_orignode(struct tipc_msg *m, u32 a)
{
msg_set_word(m, 6, a);
}
static inline u32 msg_destnode(struct tipc_msg *m)
{
return msg_word(m, 7);
}
static inline void msg_set_destnode(struct tipc_msg *m, u32 a)
{
msg_set_word(m, 7, a);
}
static inline u32 msg_nametype(struct tipc_msg *m)
{
return msg_word(m, 8);
}
static inline void msg_set_nametype(struct tipc_msg *m, u32 n)
{
msg_set_word(m, 8, n);
}
static inline u32 msg_nameinst(struct tipc_msg *m)
{
return msg_word(m, 9);
}
static inline u32 msg_namelower(struct tipc_msg *m)
{
return msg_nameinst(m);
}
static inline void msg_set_namelower(struct tipc_msg *m, u32 n)
{
msg_set_word(m, 9, n);
}
static inline void msg_set_nameinst(struct tipc_msg *m, u32 n)
{
msg_set_namelower(m, n);
}
static inline u32 msg_nameupper(struct tipc_msg *m)
{
return msg_word(m, 10);
}
static inline void msg_set_nameupper(struct tipc_msg *m, u32 n)
{
msg_set_word(m, 10, n);
}
static inline unchar *msg_data(struct tipc_msg *m)
{
return ((unchar *)m) + msg_hdr_sz(m);
}
static inline struct tipc_msg *msg_get_wrapped(struct tipc_msg *m)
{
return (struct tipc_msg *)msg_data(m);
}
/*
* Constants and routines used to read and write TIPC internal message headers
*/
/*
* Internal message users
*/
#define BCAST_PROTOCOL 5
#define MSG_BUNDLER 6
#define LINK_PROTOCOL 7
#define CONN_MANAGER 8
#define ROUTE_DISTRIBUTOR 9 /* obsoleted */
#define CHANGEOVER_PROTOCOL 10
#define NAME_DISTRIBUTOR 11
#define MSG_FRAGMENTER 12
#define LINK_CONFIG 13
/*
* Connection management protocol message types
*/
#define CONN_PROBE 0
#define CONN_PROBE_REPLY 1
#define CONN_ACK 2
/*
* Name distributor message types
*/
#define PUBLICATION 0
#define WITHDRAWAL 1
/*
* Segmentation message types
*/
#define FIRST_FRAGMENT 0
#define FRAGMENT 1
#define LAST_FRAGMENT 2
/*
* Link management protocol message types
*/
#define STATE_MSG 0
#define RESET_MSG 1
#define ACTIVATE_MSG 2
/*
* Changeover tunnel message types
*/
#define DUPLICATE_MSG 0
#define ORIGINAL_MSG 1
/*
* Config protocol message types
*/
#define DSC_REQ_MSG 0
#define DSC_RESP_MSG 1
/*
* Word 1
*/
static inline u32 msg_seq_gap(struct tipc_msg *m)
{
return msg_bits(m, 1, 16, 0x1fff);
}
static inline void msg_set_seq_gap(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 16, 0x1fff, n);
}
static inline u32 msg_node_sig(struct tipc_msg *m)
{
return msg_bits(m, 1, 0, 0xffff);
}
static inline void msg_set_node_sig(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 0, 0xffff, n);
}
/*
* Word 2
*/
static inline u32 msg_dest_domain(struct tipc_msg *m)
{
return msg_word(m, 2);
}
static inline void msg_set_dest_domain(struct tipc_msg *m, u32 n)
{
msg_set_word(m, 2, n);
}
static inline u32 msg_bcgap_after(struct tipc_msg *m)
{
return msg_bits(m, 2, 16, 0xffff);
}
static inline void msg_set_bcgap_after(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 2, 16, 0xffff, n);
}
static inline u32 msg_bcgap_to(struct tipc_msg *m)
{
return msg_bits(m, 2, 0, 0xffff);
}
static inline void msg_set_bcgap_to(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 2, 0, 0xffff, n);
}
/*
* Word 4
*/
static inline u32 msg_last_bcast(struct tipc_msg *m)
{
return msg_bits(m, 4, 16, 0xffff);
}
static inline void msg_set_last_bcast(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 16, 0xffff, n);
}
static inline void msg_set_fragm_no(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 16, 0xffff, n);
}
static inline u32 msg_next_sent(struct tipc_msg *m)
{
return msg_bits(m, 4, 0, 0xffff);
}
static inline void msg_set_next_sent(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 0, 0xffff, n);
}
static inline void msg_set_long_msgno(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 0, 0xffff, n);
}
static inline u32 msg_bc_netid(struct tipc_msg *m)
{
return msg_word(m, 4);
}
static inline void msg_set_bc_netid(struct tipc_msg *m, u32 id)
{
msg_set_word(m, 4, id);
}
static inline u32 msg_link_selector(struct tipc_msg *m)
{
return msg_bits(m, 4, 0, 1);
}
static inline void msg_set_link_selector(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 0, 1, n);
}
/*
* Word 5
*/
static inline u32 msg_session(struct tipc_msg *m)
{
return msg_bits(m, 5, 16, 0xffff);
}
static inline void msg_set_session(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 5, 16, 0xffff, n);
}
static inline u32 msg_probe(struct tipc_msg *m)
{
return msg_bits(m, 5, 0, 1);
}
static inline void msg_set_probe(struct tipc_msg *m, u32 val)
{
msg_set_bits(m, 5, 0, 1, val);
}
static inline char msg_net_plane(struct tipc_msg *m)
{
return msg_bits(m, 5, 1, 7) + 'A';
}
static inline void msg_set_net_plane(struct tipc_msg *m, char n)
{
msg_set_bits(m, 5, 1, 7, (n - 'A'));
}
static inline u32 msg_linkprio(struct tipc_msg *m)
{
return msg_bits(m, 5, 4, 0x1f);
}
static inline void msg_set_linkprio(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 5, 4, 0x1f, n);
}
static inline u32 msg_bearer_id(struct tipc_msg *m)
{
return msg_bits(m, 5, 9, 0x7);
}
static inline void msg_set_bearer_id(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 5, 9, 0x7, n);
}
static inline u32 msg_redundant_link(struct tipc_msg *m)
{
return msg_bits(m, 5, 12, 0x1);
}
static inline void msg_set_redundant_link(struct tipc_msg *m, u32 r)
{
msg_set_bits(m, 5, 12, 0x1, r);
}
static inline char *msg_media_addr(struct tipc_msg *m)
{
return (char *)&m->hdr[TIPC_MEDIA_ADDR_OFFSET];
}
/*
* Word 9
*/
static inline u32 msg_msgcnt(struct tipc_msg *m)
{
return msg_bits(m, 9, 16, 0xffff);
}
static inline void msg_set_msgcnt(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 9, 16, 0xffff, n);
}
static inline u32 msg_bcast_tag(struct tipc_msg *m)
{
return msg_bits(m, 9, 16, 0xffff);
}
static inline void msg_set_bcast_tag(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 9, 16, 0xffff, n);
}
static inline u32 msg_max_pkt(struct tipc_msg *m)
{
return msg_bits(m, 9, 16, 0xffff) * 4;
}
static inline void msg_set_max_pkt(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 9, 16, 0xffff, (n / 4));
}
static inline u32 msg_link_tolerance(struct tipc_msg *m)
{
return msg_bits(m, 9, 0, 0xffff);
}
static inline void msg_set_link_tolerance(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 9, 0, 0xffff, n);
}
u32 tipc_msg_tot_importance(struct tipc_msg *m);
void tipc_msg_init(struct tipc_msg *m, u32 user, u32 type, u32 hsize,
u32 destnode);
int tipc_msg_build(struct tipc_msg *hdr, struct iovec const *msg_sect,
unsigned int len, int max_size, struct sk_buff **buf);
#endif