linux-stable/include/uapi/linux/net_tstamp.h
Willem de Bruijn b534dc46c8 net_tstamp: add SOF_TIMESTAMPING_OPT_ID_TCP
Add an option to initialize SOF_TIMESTAMPING_OPT_ID for TCP from
write_seq sockets instead of snd_una.

This should have been the behavior from the start. Because processes
may now exist that rely on the established behavior, do not change
behavior of the existing option, but add the right behavior with a new
flag. It is encouraged to always set SOF_TIMESTAMPING_OPT_ID_TCP on
stream sockets along with the existing SOF_TIMESTAMPING_OPT_ID.

Intuitively the contract is that the counter is zero after the
setsockopt, so that the next write N results in a notification for
the last byte N - 1.

On idle sockets snd_una == write_seq and this holds for both. But on
sockets with data in transmission, snd_una records the unacked offset
in the stream. This depends on the ACK response from the peer. A
process cannot learn this in a race free manner (ioctl SIOCOUTQ is one
racy approach).

write_seq records the offset at the last byte written by the process.
This is a better starting point. It matches the intuitive contract in
all circumstances, unaffected by external behavior.

The new timestamp flag necessitates increasing sk_tsflags to 32 bits.
Move the field in struct sock to avoid growing the socket (for some
common CONFIG variants). The UAPI interface so_timestamping.flags is
already int, so 32 bits wide.

Reported-by: Sotirios Delimanolis <sotodel@meta.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20221207143701.29861-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-08 19:49:21 -08:00

205 lines
6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
* Userspace API for hardware time stamping of network packets
*
* Copyright (C) 2008,2009 Intel Corporation
* Author: Patrick Ohly <patrick.ohly@intel.com>
*
*/
#ifndef _NET_TIMESTAMPING_H
#define _NET_TIMESTAMPING_H
#include <linux/types.h>
#include <linux/socket.h> /* for SO_TIMESTAMPING */
/* SO_TIMESTAMPING flags */
enum {
SOF_TIMESTAMPING_TX_HARDWARE = (1<<0),
SOF_TIMESTAMPING_TX_SOFTWARE = (1<<1),
SOF_TIMESTAMPING_RX_HARDWARE = (1<<2),
SOF_TIMESTAMPING_RX_SOFTWARE = (1<<3),
SOF_TIMESTAMPING_SOFTWARE = (1<<4),
SOF_TIMESTAMPING_SYS_HARDWARE = (1<<5),
SOF_TIMESTAMPING_RAW_HARDWARE = (1<<6),
SOF_TIMESTAMPING_OPT_ID = (1<<7),
SOF_TIMESTAMPING_TX_SCHED = (1<<8),
SOF_TIMESTAMPING_TX_ACK = (1<<9),
SOF_TIMESTAMPING_OPT_CMSG = (1<<10),
SOF_TIMESTAMPING_OPT_TSONLY = (1<<11),
SOF_TIMESTAMPING_OPT_STATS = (1<<12),
SOF_TIMESTAMPING_OPT_PKTINFO = (1<<13),
SOF_TIMESTAMPING_OPT_TX_SWHW = (1<<14),
SOF_TIMESTAMPING_BIND_PHC = (1 << 15),
SOF_TIMESTAMPING_OPT_ID_TCP = (1 << 16),
SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_ID_TCP,
SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) |
SOF_TIMESTAMPING_LAST
};
/*
* SO_TIMESTAMPING flags are either for recording a packet timestamp or for
* reporting the timestamp to user space.
* Recording flags can be set both via socket options and control messages.
*/
#define SOF_TIMESTAMPING_TX_RECORD_MASK (SOF_TIMESTAMPING_TX_HARDWARE | \
SOF_TIMESTAMPING_TX_SOFTWARE | \
SOF_TIMESTAMPING_TX_SCHED | \
SOF_TIMESTAMPING_TX_ACK)
/**
* struct so_timestamping - SO_TIMESTAMPING parameter
*
* @flags: SO_TIMESTAMPING flags
* @bind_phc: Index of PTP virtual clock bound to sock. This is available
* if flag SOF_TIMESTAMPING_BIND_PHC is set.
*/
struct so_timestamping {
int flags;
int bind_phc;
};
/**
* struct hwtstamp_config - %SIOCGHWTSTAMP and %SIOCSHWTSTAMP parameter
*
* @flags: one of HWTSTAMP_FLAG_*
* @tx_type: one of HWTSTAMP_TX_*
* @rx_filter: one of HWTSTAMP_FILTER_*
*
* %SIOCGHWTSTAMP and %SIOCSHWTSTAMP expect a &struct ifreq with a
* ifr_data pointer to this structure. For %SIOCSHWTSTAMP, if the
* driver or hardware does not support the requested @rx_filter value,
* the driver may use a more general filter mode. In this case
* @rx_filter will indicate the actual mode on return.
*/
struct hwtstamp_config {
int flags;
int tx_type;
int rx_filter;
};
/* possible values for hwtstamp_config->flags */
enum hwtstamp_flags {
/*
* With this flag, the user could get bond active interface's
* PHC index. Note this PHC index is not stable as when there
* is a failover, the bond active interface will be changed, so
* will be the PHC index.
*/
HWTSTAMP_FLAG_BONDED_PHC_INDEX = (1<<0),
#define HWTSTAMP_FLAG_BONDED_PHC_INDEX HWTSTAMP_FLAG_BONDED_PHC_INDEX
HWTSTAMP_FLAG_LAST = HWTSTAMP_FLAG_BONDED_PHC_INDEX,
HWTSTAMP_FLAG_MASK = (HWTSTAMP_FLAG_LAST - 1) | HWTSTAMP_FLAG_LAST
};
/* possible values for hwtstamp_config->tx_type */
enum hwtstamp_tx_types {
/*
* No outgoing packet will need hardware time stamping;
* should a packet arrive which asks for it, no hardware
* time stamping will be done.
*/
HWTSTAMP_TX_OFF,
/*
* Enables hardware time stamping for outgoing packets;
* the sender of the packet decides which are to be
* time stamped by setting %SOF_TIMESTAMPING_TX_SOFTWARE
* before sending the packet.
*/
HWTSTAMP_TX_ON,
/*
* Enables time stamping for outgoing packets just as
* HWTSTAMP_TX_ON does, but also enables time stamp insertion
* directly into Sync packets. In this case, transmitted Sync
* packets will not received a time stamp via the socket error
* queue.
*/
HWTSTAMP_TX_ONESTEP_SYNC,
/*
* Same as HWTSTAMP_TX_ONESTEP_SYNC, but also enables time
* stamp insertion directly into PDelay_Resp packets. In this
* case, neither transmitted Sync nor PDelay_Resp packets will
* receive a time stamp via the socket error queue.
*/
HWTSTAMP_TX_ONESTEP_P2P,
/* add new constants above here */
__HWTSTAMP_TX_CNT
};
/* possible values for hwtstamp_config->rx_filter */
enum hwtstamp_rx_filters {
/* time stamp no incoming packet at all */
HWTSTAMP_FILTER_NONE,
/* time stamp any incoming packet */
HWTSTAMP_FILTER_ALL,
/* return value: time stamp all packets requested plus some others */
HWTSTAMP_FILTER_SOME,
/* PTP v1, UDP, any kind of event packet */
HWTSTAMP_FILTER_PTP_V1_L4_EVENT,
/* PTP v1, UDP, Sync packet */
HWTSTAMP_FILTER_PTP_V1_L4_SYNC,
/* PTP v1, UDP, Delay_req packet */
HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ,
/* PTP v2, UDP, any kind of event packet */
HWTSTAMP_FILTER_PTP_V2_L4_EVENT,
/* PTP v2, UDP, Sync packet */
HWTSTAMP_FILTER_PTP_V2_L4_SYNC,
/* PTP v2, UDP, Delay_req packet */
HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ,
/* 802.AS1, Ethernet, any kind of event packet */
HWTSTAMP_FILTER_PTP_V2_L2_EVENT,
/* 802.AS1, Ethernet, Sync packet */
HWTSTAMP_FILTER_PTP_V2_L2_SYNC,
/* 802.AS1, Ethernet, Delay_req packet */
HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ,
/* PTP v2/802.AS1, any layer, any kind of event packet */
HWTSTAMP_FILTER_PTP_V2_EVENT,
/* PTP v2/802.AS1, any layer, Sync packet */
HWTSTAMP_FILTER_PTP_V2_SYNC,
/* PTP v2/802.AS1, any layer, Delay_req packet */
HWTSTAMP_FILTER_PTP_V2_DELAY_REQ,
/* NTP, UDP, all versions and packet modes */
HWTSTAMP_FILTER_NTP_ALL,
/* add new constants above here */
__HWTSTAMP_FILTER_CNT
};
/* SCM_TIMESTAMPING_PKTINFO control message */
struct scm_ts_pktinfo {
__u32 if_index;
__u32 pkt_length;
__u32 reserved[2];
};
/*
* SO_TXTIME gets a struct sock_txtime with flags being an integer bit
* field comprised of these values.
*/
enum txtime_flags {
SOF_TXTIME_DEADLINE_MODE = (1 << 0),
SOF_TXTIME_REPORT_ERRORS = (1 << 1),
SOF_TXTIME_FLAGS_LAST = SOF_TXTIME_REPORT_ERRORS,
SOF_TXTIME_FLAGS_MASK = (SOF_TXTIME_FLAGS_LAST - 1) |
SOF_TXTIME_FLAGS_LAST
};
struct sock_txtime {
__kernel_clockid_t clockid;/* reference clockid */
__u32 flags; /* as defined by enum txtime_flags */
};
#endif /* _NET_TIMESTAMPING_H */