forked from luck/tmp_suning_uos_patched
[DCCP]: 48-bit sequence number arithmetic
This patch * organizes the sequence arithmetic functions into one corner of dccp.h * performs a small modification of dccp_set_seqno to make it more widely reusable (now it is safe to use any number, since it performs modulo-2^48 assignment) * adds functions and generic macros for 48-bit sequence arithmetic: --48 bit complement --modulo-48 addition and modulo-48 subtraction --dccp_inc_seqno now a special case of add48 Constants renamed following a suggestion by Arnaldo. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
8b5be26831
commit
6b811d43f6
|
@ -157,7 +157,7 @@ struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
|
|||
|
||||
if (av != NULL) {
|
||||
av->dccpav_buf_head = DCCP_MAX_ACKVEC_LEN - 1;
|
||||
av->dccpav_buf_ackno = DCCP_MAX_SEQNO + 1;
|
||||
av->dccpav_buf_ackno = UINT48_MAX + 1;
|
||||
av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0;
|
||||
av->dccpav_time.tv_sec = 0;
|
||||
av->dccpav_time.tv_usec = 0;
|
||||
|
|
|
@ -92,6 +92,32 @@ extern int sysctl_dccp_feat_send_ack_vector;
|
|||
extern int sysctl_dccp_feat_send_ndp_count;
|
||||
extern int sysctl_dccp_tx_qlen;
|
||||
|
||||
/*
|
||||
* 48-bit sequence number arithmetic (signed and unsigned)
|
||||
*/
|
||||
#define INT48_MIN 0x800000000000LL /* 2^47 */
|
||||
#define UINT48_MAX 0xFFFFFFFFFFFFLL /* 2^48 - 1 */
|
||||
#define COMPLEMENT48(x) (0x1000000000000LL - (x)) /* 2^48 - x */
|
||||
#define TO_SIGNED48(x) (((x) < INT48_MIN)? (x) : -COMPLEMENT48( (x)))
|
||||
#define TO_UNSIGNED48(x) (((x) >= 0)? (x) : COMPLEMENT48(-(x)))
|
||||
#define ADD48(a, b) (((a) + (b)) & UINT48_MAX)
|
||||
#define SUB48(a, b) ADD48((a), COMPLEMENT48(b))
|
||||
|
||||
static inline void dccp_set_seqno(u64 *seqno, u64 value)
|
||||
{
|
||||
*seqno = value & UINT48_MAX;
|
||||
}
|
||||
|
||||
static inline void dccp_inc_seqno(u64 *seqno)
|
||||
{
|
||||
*seqno = ADD48(*seqno, 1);
|
||||
}
|
||||
|
||||
static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2)
|
||||
{
|
||||
return ((seqno2 << 16) - (seqno1 << 16)) >> 16;
|
||||
}
|
||||
|
||||
/* is seq1 < seq2 ? */
|
||||
static inline int before48(const u64 seq1, const u64 seq2)
|
||||
{
|
||||
|
@ -313,26 +339,7 @@ static inline int dccp_packet_without_ack(const struct sk_buff *skb)
|
|||
return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST;
|
||||
}
|
||||
|
||||
#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1)
|
||||
#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2)
|
||||
|
||||
static inline void dccp_set_seqno(u64 *seqno, u64 value)
|
||||
{
|
||||
if (value > DCCP_MAX_SEQNO)
|
||||
value -= DCCP_MAX_SEQNO + 1;
|
||||
*seqno = value;
|
||||
}
|
||||
|
||||
static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2)
|
||||
{
|
||||
return ((seqno2 << 16) - (seqno1 << 16)) >> 16;
|
||||
}
|
||||
|
||||
static inline void dccp_inc_seqno(u64 *seqno)
|
||||
{
|
||||
if (++*seqno > DCCP_MAX_SEQNO)
|
||||
*seqno = 0;
|
||||
}
|
||||
#define DCCP_PKT_WITHOUT_ACK_SEQ (UINT48_MAX << 2)
|
||||
|
||||
static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss)
|
||||
{
|
||||
|
|
Loading…
Reference in New Issue
Block a user