msg.h

linux 内核源代码

 */

static inline u32 msg_seq_gap(struct tipc_msg *m)
{
	return msg_bits(m, 1, 16, 0xff);
}

static inline void msg_set_seq_gap(struct tipc_msg *m, u32 n)
{
	msg_set_bits(m, 1, 16, 0xff, n);
}

static inline u32 msg_req_links(struct tipc_msg *m)
{
	return msg_bits(m, 1, 16, 0xfff);
}

static inline void msg_set_req_links(struct tipc_msg *m, u32 n)
{
	msg_set_bits(m, 1, 16, 0xfff, 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 u32 msg_fragm_no(struct tipc_msg *m)
{
	return msg_bits(m, 4, 16, 0xffff);
}

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 u32 msg_long_msgno(struct tipc_msg *m)
{
	return msg_bits(m, 4, 0, 0xffff);
}

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 & 1));
}

/*
 * 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 & 1));
}

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)
{
	msg_set_bits(m, 5, 12, 0x1, 1);
}

static inline void msg_clear_redundant_link(struct tipc_msg *m)
{
	msg_set_bits(m, 5, 12, 0x1, 0);
}


/*
 * 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);
}

/*
 * Routing table message data
 */


static inline u32 msg_remote_node(struct tipc_msg *m)
{
	return msg_word(m, msg_hdr_sz(m)/4);
}

static inline void msg_set_remote_node(struct tipc_msg *m, u32 a)
{
	msg_set_word(m, msg_hdr_sz(m)/4, a);
}

static inline int msg_dataoctet(struct tipc_msg *m, u32 pos)
{
	return(msg_data(m)[pos + 4] != 0);
}

static inline void msg_set_dataoctet(struct tipc_msg *m, u32 pos)
{
	msg_data(m)[pos + 4] = 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

/*
 * Routing table message types
 */
#define EXT_ROUTING_TABLE    0
#define LOCAL_ROUTING_TABLE  1
#define SLAVE_ROUTING_TABLE  2
#define ROUTE_ADDITION       3
#define ROUTE_REMOVAL        4

/*
 * Config protocol message types
 */

#define DSC_REQ_MSG          0
#define DSC_RESP_MSG         1

static inline u32 msg_tot_importance(struct tipc_msg *m)
{
	if (likely(msg_isdata(m))) {
		if (likely(msg_orignode(m) == tipc_own_addr))
			return msg_importance(m);
		return msg_importance(m) + 4;
	}
	if ((msg_user(m) == MSG_FRAGMENTER)  &&
	    (msg_type(m) == FIRST_FRAGMENT))
		return msg_importance(msg_get_wrapped(m));
	return msg_importance(m);
}


static inline void msg_init(struct tipc_msg *m, u32 user, u32 type,
			    u32 err, u32 hsize, u32 destnode)
{
	memset(m, 0, hsize);
	msg_set_version(m);
	msg_set_user(m, user);
	msg_set_hdr_sz(m, hsize);
	msg_set_size(m, hsize);
	msg_set_prevnode(m, tipc_own_addr);
	msg_set_type(m, type);
	msg_set_errcode(m, err);
	if (!msg_short(m)) {
		msg_set_orignode(m, tipc_own_addr);
		msg_set_destnode(m, destnode);
	}
}

/**
 * msg_calc_data_size - determine total data size for message
 */

static inline int msg_calc_data_size(struct iovec const *msg_sect, u32 num_sect)
{
	int dsz = 0;
	int i;

	for (i = 0; i < num_sect; i++)
		dsz += msg_sect[i].iov_len;
	return dsz;
}

/**
 * msg_build - create message using specified header and data
 *
 * Note: Caller must not hold any locks in case copy_from_user() is interrupted!
 *
 * Returns message data size or errno
 */

static inline int msg_build(struct tipc_msg *hdr,
			    struct iovec const *msg_sect, u32 num_sect,
			    int max_size, int usrmem, struct sk_buff** buf)
{
	int dsz, sz, hsz, pos, res, cnt;

	dsz = msg_calc_data_size(msg_sect, num_sect);
	if (unlikely(dsz > TIPC_MAX_USER_MSG_SIZE)) {
		*buf = NULL;
		return -EINVAL;
	}

	pos = hsz = msg_hdr_sz(hdr);
	sz = hsz + dsz;
	msg_set_size(hdr, sz);
	if (unlikely(sz > max_size)) {
		*buf = NULL;
		return dsz;
	}

	*buf = buf_acquire(sz);
	if (!(*buf))
		return -ENOMEM;
	skb_copy_to_linear_data(*buf, hdr, hsz);
	for (res = 1, cnt = 0; res && (cnt < num_sect); cnt++) {
		if (likely(usrmem))
			res = !copy_from_user((*buf)->data + pos,
					      msg_sect[cnt].iov_base,
					      msg_sect[cnt].iov_len);
		else
			skb_copy_to_linear_data_offset(*buf, pos,
						       msg_sect[cnt].iov_base,
						       msg_sect[cnt].iov_len);
		pos += msg_sect[cnt].iov_len;
	}
	if (likely(res))
		return dsz;

	buf_discard(*buf);
	*buf = NULL;
	return -EFAULT;
}

static inline void msg_set_media_addr(struct tipc_msg *m, struct tipc_media_addr *a)
{
	memcpy(&((int *)m)[5], a, sizeof(*a));
}

static inline void msg_get_media_addr(struct tipc_msg *m, struct tipc_media_addr *a)
{
	memcpy(a, &((int*)m)[5], sizeof(*a));
}

#endif