* [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
@ 2024-06-12 15:47 ` Laurent Vivier
2024-06-12 21:22 ` Stefano Brivio
2024-06-12 15:47 ` [PATCH v6 2/8] tcp: move buffers management functions to their own file Laurent Vivier
` (7 subsequent siblings)
8 siblings, 1 reply; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 15:47 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
This commit isolates the internal data structure management used for storing
data (e.g., tcp4_l2_flags_iov[], tcp6_l2_flags_iov[], tcp4_flags_ip[],
tcp4_flags[], ...) from the tcp_send_flag() function. The extracted
functionality is relocated to a new function named tcp_fill_flag_header().
tcp_fill_flag_header() is now a generic function that accepts parameters such
as struct tcphdr and a data pointer. tcp_send_flag() utilizes this parameter to
pass memory pointers from tcp4_l2_flags_iov[] and tcp6_l2_flags_iov[].
This separation sets the stage for utilizing tcp_fill_flag_header() to
set the memory provided by the guest via vhost-user in future developments.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
Notes:
v6:
- rename tcp_fill_flag_header() to tcp_prepare_flags()
- set optlen to 0 in tcp_prepare_flags()
v5:
- use tcp_fill_flag_header() rather than tcp_fill_headers4() and
tcp_fill_headers6().
tcp.c | 72 +++++++++++++++++++++++++++++++++++++++--------------------
1 file changed, 48 insertions(+), 24 deletions(-)
diff --git a/tcp.c b/tcp.c
index dd8d46e08628..6800209d4122 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1567,24 +1567,25 @@ static void tcp_update_seqack_from_tap(const struct ctx *c,
}
/**
- * tcp_send_flag() - Send segment with flags to tap (no payload)
+ * tcp_prepare_flags() - Prepare header for flags-only segment (no payload)
* @c: Execution context
* @conn: Connection pointer
* @flags: TCP flags: if not set, send segment only if ACK is due
+ * @th: TCP header to update
+ * @data: buffer to store TCP option
+ * @optlen: size of the TCP option buffer (output parameter)
*
- * Return: negative error code on connection reset, 0 otherwise
+ * Return: < 0 error code on connection reset,
+ * 0 if there is no flag to send
+ * 1 otherwise
*/
-static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
+static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
+ int flags, struct tcphdr *th, char *data,
+ size_t *optlen)
{
- struct tcp_flags_t *payload;
struct tcp_info tinfo = { 0 };
socklen_t sl = sizeof(tinfo);
int s = conn->sock;
- size_t optlen = 0;
- struct tcphdr *th;
- struct iovec *iov;
- size_t l4len;
- char *data;
if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap) &&
!flags && conn->wnd_to_tap)
@@ -1606,20 +1607,11 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
return 0;
- if (CONN_V4(conn))
- iov = tcp4_l2_flags_iov[tcp4_flags_used++];
- else
- iov = tcp6_l2_flags_iov[tcp6_flags_used++];
-
- payload = iov[TCP_IOV_PAYLOAD].iov_base;
- th = &payload->th;
- data = payload->opts;
-
if (flags & SYN) {
int mss;
/* Options: MSS, NOP and window scale (8 bytes) */
- optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
+ *optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
*data++ = OPT_MSS;
*data++ = OPT_MSS_LEN;
@@ -1651,19 +1643,16 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
*data++ = conn->ws_to_tap;
} else if (!(flags & RST)) {
flags |= ACK;
+ *optlen = 0;
}
- th->doff = (sizeof(*th) + optlen) / 4;
+ th->doff = (sizeof(*th) + *optlen) / 4;
th->ack = !!(flags & ACK);
th->rst = !!(flags & RST);
th->syn = !!(flags & SYN);
th->fin = !!(flags & FIN);
- l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
- conn->seq_to_tap);
- iov[TCP_IOV_PAYLOAD].iov_len = l4len;
-
if (th->ack) {
if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap))
conn_flag(c, conn, ~ACK_TO_TAP_DUE);
@@ -1678,6 +1667,41 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
if (th->fin || th->syn)
conn->seq_to_tap++;
+ return 1;
+}
+
+/**
+ * tcp_send_flag() - Send segment with flags to tap (no payload)
+ * @c: Execution context
+ * @conn: Connection pointer
+ * @flags: TCP flags: if not set, send segment only if ACK is due
+ *
+ * Return: negative error code on connection reset, 0 otherwise
+ */
+static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
+{
+ struct tcp_flags_t *payload;
+ struct iovec *iov;
+ size_t optlen;
+ size_t l4len;
+ int ret;
+
+ if (CONN_V4(conn))
+ iov = tcp4_l2_flags_iov[tcp4_flags_used++];
+ else
+ iov = tcp6_l2_flags_iov[tcp6_flags_used++];
+
+ payload = iov[TCP_IOV_PAYLOAD].iov_base;
+
+ ret = tcp_prepare_flags(c, conn, flags, &payload->th,
+ payload->opts, &optlen);
+ if (ret <= 0)
+ return ret;
+
+ l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
+ conn->seq_to_tap);
+ iov[TCP_IOV_PAYLOAD].iov_len = l4len;
+
if (flags & DUP_ACK) {
struct iovec *dup_iov;
int i;
--
@@ -1567,24 +1567,25 @@ static void tcp_update_seqack_from_tap(const struct ctx *c,
}
/**
- * tcp_send_flag() - Send segment with flags to tap (no payload)
+ * tcp_prepare_flags() - Prepare header for flags-only segment (no payload)
* @c: Execution context
* @conn: Connection pointer
* @flags: TCP flags: if not set, send segment only if ACK is due
+ * @th: TCP header to update
+ * @data: buffer to store TCP option
+ * @optlen: size of the TCP option buffer (output parameter)
*
- * Return: negative error code on connection reset, 0 otherwise
+ * Return: < 0 error code on connection reset,
+ * 0 if there is no flag to send
+ * 1 otherwise
*/
-static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
+static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
+ int flags, struct tcphdr *th, char *data,
+ size_t *optlen)
{
- struct tcp_flags_t *payload;
struct tcp_info tinfo = { 0 };
socklen_t sl = sizeof(tinfo);
int s = conn->sock;
- size_t optlen = 0;
- struct tcphdr *th;
- struct iovec *iov;
- size_t l4len;
- char *data;
if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap) &&
!flags && conn->wnd_to_tap)
@@ -1606,20 +1607,11 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
return 0;
- if (CONN_V4(conn))
- iov = tcp4_l2_flags_iov[tcp4_flags_used++];
- else
- iov = tcp6_l2_flags_iov[tcp6_flags_used++];
-
- payload = iov[TCP_IOV_PAYLOAD].iov_base;
- th = &payload->th;
- data = payload->opts;
-
if (flags & SYN) {
int mss;
/* Options: MSS, NOP and window scale (8 bytes) */
- optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
+ *optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
*data++ = OPT_MSS;
*data++ = OPT_MSS_LEN;
@@ -1651,19 +1643,16 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
*data++ = conn->ws_to_tap;
} else if (!(flags & RST)) {
flags |= ACK;
+ *optlen = 0;
}
- th->doff = (sizeof(*th) + optlen) / 4;
+ th->doff = (sizeof(*th) + *optlen) / 4;
th->ack = !!(flags & ACK);
th->rst = !!(flags & RST);
th->syn = !!(flags & SYN);
th->fin = !!(flags & FIN);
- l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
- conn->seq_to_tap);
- iov[TCP_IOV_PAYLOAD].iov_len = l4len;
-
if (th->ack) {
if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap))
conn_flag(c, conn, ~ACK_TO_TAP_DUE);
@@ -1678,6 +1667,41 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
if (th->fin || th->syn)
conn->seq_to_tap++;
+ return 1;
+}
+
+/**
+ * tcp_send_flag() - Send segment with flags to tap (no payload)
+ * @c: Execution context
+ * @conn: Connection pointer
+ * @flags: TCP flags: if not set, send segment only if ACK is due
+ *
+ * Return: negative error code on connection reset, 0 otherwise
+ */
+static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
+{
+ struct tcp_flags_t *payload;
+ struct iovec *iov;
+ size_t optlen;
+ size_t l4len;
+ int ret;
+
+ if (CONN_V4(conn))
+ iov = tcp4_l2_flags_iov[tcp4_flags_used++];
+ else
+ iov = tcp6_l2_flags_iov[tcp6_flags_used++];
+
+ payload = iov[TCP_IOV_PAYLOAD].iov_base;
+
+ ret = tcp_prepare_flags(c, conn, flags, &payload->th,
+ payload->opts, &optlen);
+ if (ret <= 0)
+ return ret;
+
+ l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
+ conn->seq_to_tap);
+ iov[TCP_IOV_PAYLOAD].iov_len = l4len;
+
if (flags & DUP_ACK) {
struct iovec *dup_iov;
int i;
--
2.45.2
^ permalink raw reply related [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-12 15:47 ` [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag() Laurent Vivier
@ 2024-06-12 21:22 ` Stefano Brivio
2024-06-13 6:07 ` Stefano Brivio
2024-06-13 7:31 ` Laurent Vivier
0 siblings, 2 replies; 25+ messages in thread
From: Stefano Brivio @ 2024-06-12 21:22 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
I couldn't find out why this patch breaks the the pasta_podman/bats
test, yet, that is:
not ok 19 [505] Single TCP port forwarding, IPv4, tap
# (from function `bail-now' in file test/podman/test/system/helpers.bash, line 235,
# from function `assert' in file test/podman/test/system/helpers.bash, line 929,
# from function `pasta_test_do' in file test/podman/test/system/505-networking-pasta.bats, line 239,
# in test file test/podman/test/system/505-networking-pasta.bats, line 472)
# `pasta_test_do' failed
#
# [22:54:18.306131353] $ test/podman/bin/podman rm -t 0 --all --force --ignore
#
# [22:54:18.367462243] $ test/podman/bin/podman ps --all --external --format {{.ID}} {{.Names}}
#
# [22:54:18.394935392] $ test/podman/bin/podman images --all --format {{.Repository}}:{{.Tag}} {{.ID}}
# [22:54:18.419773379] quay.io/libpod/testimage:20240123 1f6acd4c4a1d
#
# [22:54:19.246631856] $ test/podman/bin/podman info --format {{.Host.Pasta.Executable}}
# [22:54:20.084392405] /home/sbrivio/passt/pasta
#
# [22:54:20.167980222] $ test/podman/bin/podman run --net=pasta -p [88.198.0.164]:5727:5727/tcp quay.io/libpod/testimage:20240123 sh -c for port in $(seq 5727 5727); do socat -u TCP4-LISTEN:${port},bind=[88.198.0.164] STDOUT & done; wait
# [22:54:37.256040883] x2024/06/12 20:54:37 socat[3] E read(6, 0x7fe675cd6000, 8192): Connection reset by peer
# #/vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
# #| FAIL: Mismatch between data sent and received
# #| expected: = x
# #| actual: x2024/06/12 20:54:37 socat\[3\] E read\(6\, 0x7fe675cd6000\, 8192\): Connection reset by peer
# #\^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
meaning that the data transfer is actually fine, but we reset the
connection instead of an orderly shutdown.
I found a few issues while looking for that:
On Wed, 12 Jun 2024 17:47:27 +0200
Laurent Vivier <lvivier@redhat.com> wrote:
> This commit isolates the internal data structure management used for storing
> data (e.g., tcp4_l2_flags_iov[], tcp6_l2_flags_iov[], tcp4_flags_ip[],
> tcp4_flags[], ...) from the tcp_send_flag() function. The extracted
> functionality is relocated to a new function named tcp_fill_flag_header().
>
> tcp_fill_flag_header() is now a generic function that accepts parameters such
> as struct tcphdr and a data pointer. tcp_send_flag() utilizes this parameter to
> pass memory pointers from tcp4_l2_flags_iov[] and tcp6_l2_flags_iov[].
>
> This separation sets the stage for utilizing tcp_fill_flag_header() to
> set the memory provided by the guest via vhost-user in future developments.
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
>
> Notes:
> v6:
> - rename tcp_fill_flag_header() to tcp_prepare_flags()
> - set optlen to 0 in tcp_prepare_flags()
>
> v5:
> - use tcp_fill_flag_header() rather than tcp_fill_headers4() and
> tcp_fill_headers6().
>
> tcp.c | 72 +++++++++++++++++++++++++++++++++++++++--------------------
> 1 file changed, 48 insertions(+), 24 deletions(-)
>
> diff --git a/tcp.c b/tcp.c
> index dd8d46e08628..6800209d4122 100644
> --- a/tcp.c
> +++ b/tcp.c
> @@ -1567,24 +1567,25 @@ static void tcp_update_seqack_from_tap(const struct ctx *c,
> }
>
> /**
> - * tcp_send_flag() - Send segment with flags to tap (no payload)
> + * tcp_prepare_flags() - Prepare header for flags-only segment (no payload)
> * @c: Execution context
> * @conn: Connection pointer
> * @flags: TCP flags: if not set, send segment only if ACK is due
> + * @th: TCP header to update
> + * @data: buffer to store TCP option
> + * @optlen: size of the TCP option buffer (output parameter)
> *
> - * Return: negative error code on connection reset, 0 otherwise
> + * Return: < 0 error code on connection reset,
> + * 0 if there is no flag to send
> + * 1 otherwise
This is often called with if (tcp_send_flag(...)) or
if (!tcp_send_flag(...)). Those need to be replaced with
if (tcp_send_flag(...) < 0) or if (tcp_send_flag(...) >= 0) in the
callers.
> */
> -static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> +static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> + int flags, struct tcphdr *th, char *data,
> + size_t *optlen)
> {
> - struct tcp_flags_t *payload;
> struct tcp_info tinfo = { 0 };
> socklen_t sl = sizeof(tinfo);
> int s = conn->sock;
> - size_t optlen = 0;
> - struct tcphdr *th;
> - struct iovec *iov;
> - size_t l4len;
> - char *data;
>
> if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap) &&
> !flags && conn->wnd_to_tap)
> @@ -1606,20 +1607,11 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
> return 0;
>
> - if (CONN_V4(conn))
> - iov = tcp4_l2_flags_iov[tcp4_flags_used++];
> - else
> - iov = tcp6_l2_flags_iov[tcp6_flags_used++];
> -
> - payload = iov[TCP_IOV_PAYLOAD].iov_base;
> - th = &payload->th;
> - data = payload->opts;
> -
> if (flags & SYN) {
> int mss;
>
> /* Options: MSS, NOP and window scale (8 bytes) */
> - optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
> + *optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
>
> *data++ = OPT_MSS;
> *data++ = OPT_MSS_LEN;
> @@ -1651,19 +1643,16 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> *data++ = conn->ws_to_tap;
> } else if (!(flags & RST)) {
> flags |= ACK;
> + *optlen = 0;
*optlen also needs to be set to 0 if (flags & RST), say:
} else {
*optlen = 0;
if (!(flags & RST))
flags |= ACK;
}
> }
>
> - th->doff = (sizeof(*th) + optlen) / 4;
> + th->doff = (sizeof(*th) + *optlen) / 4;
>
> th->ack = !!(flags & ACK);
> th->rst = !!(flags & RST);
> th->syn = !!(flags & SYN);
> th->fin = !!(flags & FIN);
>
> - l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
> - conn->seq_to_tap);
> - iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> -
> if (th->ack) {
> if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap))
> conn_flag(c, conn, ~ACK_TO_TAP_DUE);
> @@ -1678,6 +1667,41 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> if (th->fin || th->syn)
> conn->seq_to_tap++;
>
> + return 1;
> +}
> +
> +/**
> + * tcp_send_flag() - Send segment with flags to tap (no payload)
> + * @c: Execution context
> + * @conn: Connection pointer
> + * @flags: TCP flags: if not set, send segment only if ACK is due
> + *
> + * Return: negative error code on connection reset, 0 otherwise
> + */
> +static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> +{
> + struct tcp_flags_t *payload;
> + struct iovec *iov;
> + size_t optlen;
> + size_t l4len;
> + int ret;
> +
> + if (CONN_V4(conn))
> + iov = tcp4_l2_flags_iov[tcp4_flags_used++];
> + else
> + iov = tcp6_l2_flags_iov[tcp6_flags_used++];
We increase the counters here, but we don't decrease them back if we
hit if (ret <= 0) return ret; later.
> +
> + payload = iov[TCP_IOV_PAYLOAD].iov_base;
> +
> + ret = tcp_prepare_flags(c, conn, flags, &payload->th,
> + payload->opts, &optlen);
> + if (ret <= 0)
> + return ret;
> +
> + l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
> + conn->seq_to_tap);
> + iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> +
> if (flags & DUP_ACK) {
> struct iovec *dup_iov;
> int i;
Here's the diff I have so far, I'm not necessarily recommending any of
that, it was just a quick try:
diff --git a/tcp.c b/tcp.c
index 6800209..6bff6bc 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1644,6 +1644,8 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
} else if (!(flags & RST)) {
flags |= ACK;
*optlen = 0;
+ } else {
+ *optlen = 0;
}
th->doff = (sizeof(*th) + *optlen) / 4;
@@ -1695,8 +1697,14 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
ret = tcp_prepare_flags(c, conn, flags, &payload->th,
payload->opts, &optlen);
- if (ret <= 0)
+ if (ret <= 0) {
+ if (CONN_V4(conn))
+ tcp4_flags_used--;
+ else
+ tcp6_flags_used--;
+
return ret;
+ }
l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
conn->seq_to_tap);
@@ -1738,7 +1746,7 @@ static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn)
if (conn->events == CLOSED)
return;
- if (!tcp_send_flag(c, conn, RST))
+ if (tcp_send_flag(c, conn, RST) >= 0)
conn_event(c, conn, CLOSED);
}
@@ -2111,7 +2119,7 @@ static void tcp_conn_from_tap(struct ctx *c, sa_family_t af,
} else {
tcp_get_sndbuf(conn);
- if (tcp_send_flag(c, conn, SYN | ACK))
+ if (tcp_send_flag(c, conn, SYN | ACK) < 0)
goto cancel;
conn_event(c, conn, TAP_SYN_ACK_SENT);
@@ -2282,9 +2290,11 @@ static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn)
if (!len) {
if ((conn->events & (SOCK_FIN_RCVD | TAP_FIN_SENT)) == SOCK_FIN_RCVD) {
- if ((ret = tcp_send_flag(c, conn, FIN | ACK))) {
+ int rc = tcp_send_flag(c, conn, FIN | ACK);
+
+ if (rc < 0) {
tcp_rst(c, conn);
- return ret;
+ return rc;
}
conn_event(c, conn, TAP_FIN_SENT);
@@ -2716,7 +2726,7 @@ static void tcp_connect_finish(struct ctx *c, struct tcp_tap_conn *conn)
return;
}
- if (tcp_send_flag(c, conn, SYN | ACK))
+ if (tcp_send_flag(c, conn, SYN | ACK) < 0)
return;
conn_event(c, conn, TAP_SYN_ACK_SENT);
--
@@ -1644,6 +1644,8 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
} else if (!(flags & RST)) {
flags |= ACK;
*optlen = 0;
+ } else {
+ *optlen = 0;
}
th->doff = (sizeof(*th) + *optlen) / 4;
@@ -1695,8 +1697,14 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
ret = tcp_prepare_flags(c, conn, flags, &payload->th,
payload->opts, &optlen);
- if (ret <= 0)
+ if (ret <= 0) {
+ if (CONN_V4(conn))
+ tcp4_flags_used--;
+ else
+ tcp6_flags_used--;
+
return ret;
+ }
l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
conn->seq_to_tap);
@@ -1738,7 +1746,7 @@ static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn)
if (conn->events == CLOSED)
return;
- if (!tcp_send_flag(c, conn, RST))
+ if (tcp_send_flag(c, conn, RST) >= 0)
conn_event(c, conn, CLOSED);
}
@@ -2111,7 +2119,7 @@ static void tcp_conn_from_tap(struct ctx *c, sa_family_t af,
} else {
tcp_get_sndbuf(conn);
- if (tcp_send_flag(c, conn, SYN | ACK))
+ if (tcp_send_flag(c, conn, SYN | ACK) < 0)
goto cancel;
conn_event(c, conn, TAP_SYN_ACK_SENT);
@@ -2282,9 +2290,11 @@ static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn)
if (!len) {
if ((conn->events & (SOCK_FIN_RCVD | TAP_FIN_SENT)) == SOCK_FIN_RCVD) {
- if ((ret = tcp_send_flag(c, conn, FIN | ACK))) {
+ int rc = tcp_send_flag(c, conn, FIN | ACK);
+
+ if (rc < 0) {
tcp_rst(c, conn);
- return ret;
+ return rc;
}
conn_event(c, conn, TAP_FIN_SENT);
@@ -2716,7 +2726,7 @@ static void tcp_connect_finish(struct ctx *c, struct tcp_tap_conn *conn)
return;
}
- if (tcp_send_flag(c, conn, SYN | ACK))
+ if (tcp_send_flag(c, conn, SYN | ACK) < 0)
return;
conn_event(c, conn, TAP_SYN_ACK_SENT);
--
Stefano
^ permalink raw reply related [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-12 21:22 ` Stefano Brivio
@ 2024-06-13 6:07 ` Stefano Brivio
2024-06-13 8:24 ` Laurent Vivier
2024-06-13 7:31 ` Laurent Vivier
1 sibling, 1 reply; 25+ messages in thread
From: Stefano Brivio @ 2024-06-13 6:07 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
On Wed, 12 Jun 2024 23:22:10 +0200
Stefano Brivio <sbrivio@redhat.com> wrote:
> I couldn't find out why this patch breaks the the pasta_podman/bats
> test, yet, that is:
>
> not ok 19 [505] Single TCP port forwarding, IPv4, tap
> # (from function `bail-now' in file test/podman/test/system/helpers.bash, line 235,
> # from function `assert' in file test/podman/test/system/helpers.bash, line 929,
> # from function `pasta_test_do' in file test/podman/test/system/505-networking-pasta.bats, line 239,
> # in test file test/podman/test/system/505-networking-pasta.bats, line 472)
> # `pasta_test_do' failed
> #
> # [22:54:18.306131353] $ test/podman/bin/podman rm -t 0 --all --force --ignore
> #
> # [22:54:18.367462243] $ test/podman/bin/podman ps --all --external --format {{.ID}} {{.Names}}
> #
> # [22:54:18.394935392] $ test/podman/bin/podman images --all --format {{.Repository}}:{{.Tag}} {{.ID}}
> # [22:54:18.419773379] quay.io/libpod/testimage:20240123 1f6acd4c4a1d
> #
> # [22:54:19.246631856] $ test/podman/bin/podman info --format {{.Host.Pasta.Executable}}
> # [22:54:20.084392405] /home/sbrivio/passt/pasta
> #
> # [22:54:20.167980222] $ test/podman/bin/podman run --net=pasta -p [88.198.0.164]:5727:5727/tcp quay.io/libpod/testimage:20240123 sh -c for port in $(seq 5727 5727); do socat -u TCP4-LISTEN:${port},bind=[88.198.0.164] STDOUT & done; wait
> # [22:54:37.256040883] x2024/06/12 20:54:37 socat[3] E read(6, 0x7fe675cd6000, 8192): Connection reset by peer
> # #/vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
> # #| FAIL: Mismatch between data sent and received
> # #| expected: = x
> # #| actual: x2024/06/12 20:54:37 socat\[3\] E read\(6\, 0x7fe675cd6000\, 8192\): Connection reset by peer
> # #\^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
> meaning that the data transfer is actually fine, but we reset the
> connection instead of an orderly shutdown.
>
> I found a few issues while looking for that:
>
> On Wed, 12 Jun 2024 17:47:27 +0200
> Laurent Vivier <lvivier@redhat.com> wrote:
>
> > This commit isolates the internal data structure management used for storing
> > data (e.g., tcp4_l2_flags_iov[], tcp6_l2_flags_iov[], tcp4_flags_ip[],
> > tcp4_flags[], ...) from the tcp_send_flag() function. The extracted
> > functionality is relocated to a new function named tcp_fill_flag_header().
> >
> > tcp_fill_flag_header() is now a generic function that accepts parameters such
> > as struct tcphdr and a data pointer. tcp_send_flag() utilizes this parameter to
> > pass memory pointers from tcp4_l2_flags_iov[] and tcp6_l2_flags_iov[].
> >
> > This separation sets the stage for utilizing tcp_fill_flag_header() to
> > set the memory provided by the guest via vhost-user in future developments.
> >
> > Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> > ---
> >
> > Notes:
> > v6:
> > - rename tcp_fill_flag_header() to tcp_prepare_flags()
> > - set optlen to 0 in tcp_prepare_flags()
> >
> > v5:
> > - use tcp_fill_flag_header() rather than tcp_fill_headers4() and
> > tcp_fill_headers6().
> >
> > tcp.c | 72 +++++++++++++++++++++++++++++++++++++++--------------------
> > 1 file changed, 48 insertions(+), 24 deletions(-)
> >
> > diff --git a/tcp.c b/tcp.c
> > index dd8d46e08628..6800209d4122 100644
> > --- a/tcp.c
> > +++ b/tcp.c
> > @@ -1567,24 +1567,25 @@ static void tcp_update_seqack_from_tap(const struct ctx *c,
> > }
> >
> > /**
> > - * tcp_send_flag() - Send segment with flags to tap (no payload)
> > + * tcp_prepare_flags() - Prepare header for flags-only segment (no payload)
> > * @c: Execution context
> > * @conn: Connection pointer
> > * @flags: TCP flags: if not set, send segment only if ACK is due
> > + * @th: TCP header to update
> > + * @data: buffer to store TCP option
> > + * @optlen: size of the TCP option buffer (output parameter)
> > *
> > - * Return: negative error code on connection reset, 0 otherwise
> > + * Return: < 0 error code on connection reset,
> > + * 0 if there is no flag to send
> > + * 1 otherwise
>
> This is often called with if (tcp_send_flag(...)) or
> if (!tcp_send_flag(...)). Those need to be replaced with
> if (tcp_send_flag(...) < 0) or if (tcp_send_flag(...) >= 0) in the
> callers.
Ah, no, sorry, you already took care of this in the new
tcp_send_flag(). Then there must be something else...
> > */
> > -static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> > +static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> > + int flags, struct tcphdr *th, char *data,
> > + size_t *optlen)
> > {
> > - struct tcp_flags_t *payload;
> > struct tcp_info tinfo = { 0 };
> > socklen_t sl = sizeof(tinfo);
> > int s = conn->sock;
> > - size_t optlen = 0;
> > - struct tcphdr *th;
> > - struct iovec *iov;
> > - size_t l4len;
> > - char *data;
> >
> > if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap) &&
> > !flags && conn->wnd_to_tap)
> > @@ -1606,20 +1607,11 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> > if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
> > return 0;
> >
> > - if (CONN_V4(conn))
> > - iov = tcp4_l2_flags_iov[tcp4_flags_used++];
> > - else
> > - iov = tcp6_l2_flags_iov[tcp6_flags_used++];
> > -
> > - payload = iov[TCP_IOV_PAYLOAD].iov_base;
> > - th = &payload->th;
> > - data = payload->opts;
> > -
> > if (flags & SYN) {
> > int mss;
> >
> > /* Options: MSS, NOP and window scale (8 bytes) */
> > - optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
> > + *optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
> >
> > *data++ = OPT_MSS;
> > *data++ = OPT_MSS_LEN;
> > @@ -1651,19 +1643,16 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> > *data++ = conn->ws_to_tap;
> > } else if (!(flags & RST)) {
> > flags |= ACK;
> > + *optlen = 0;
>
> *optlen also needs to be set to 0 if (flags & RST), say:
>
> } else {
> *optlen = 0;
>
> if (!(flags & RST))
> flags |= ACK;
> }
>
> > }
> >
> > - th->doff = (sizeof(*th) + optlen) / 4;
> > + th->doff = (sizeof(*th) + *optlen) / 4;
> >
> > th->ack = !!(flags & ACK);
> > th->rst = !!(flags & RST);
> > th->syn = !!(flags & SYN);
> > th->fin = !!(flags & FIN);
> >
> > - l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
> > - conn->seq_to_tap);
> > - iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> > -
> > if (th->ack) {
> > if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap))
> > conn_flag(c, conn, ~ACK_TO_TAP_DUE);
> > @@ -1678,6 +1667,41 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> > if (th->fin || th->syn)
> > conn->seq_to_tap++;
> >
> > + return 1;
> > +}
> > +
> > +/**
> > + * tcp_send_flag() - Send segment with flags to tap (no payload)
> > + * @c: Execution context
> > + * @conn: Connection pointer
> > + * @flags: TCP flags: if not set, send segment only if ACK is due
> > + *
> > + * Return: negative error code on connection reset, 0 otherwise
> > + */
> > +static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> > +{
> > + struct tcp_flags_t *payload;
> > + struct iovec *iov;
> > + size_t optlen;
> > + size_t l4len;
> > + int ret;
> > +
> > + if (CONN_V4(conn))
> > + iov = tcp4_l2_flags_iov[tcp4_flags_used++];
> > + else
> > + iov = tcp6_l2_flags_iov[tcp6_flags_used++];
>
> We increase the counters here, but we don't decrease them back if we
> hit if (ret <= 0) return ret; later.
>
> > +
> > + payload = iov[TCP_IOV_PAYLOAD].iov_base;
> > +
> > + ret = tcp_prepare_flags(c, conn, flags, &payload->th,
> > + payload->opts, &optlen);
> > + if (ret <= 0)
> > + return ret;
> > +
> > + l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
> > + conn->seq_to_tap);
> > + iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> > +
> > if (flags & DUP_ACK) {
> > struct iovec *dup_iov;
> > int i;
>
> Here's the diff I have so far, I'm not necessarily recommending any of
> that, it was just a quick try:
>
> diff --git a/tcp.c b/tcp.c
> index 6800209..6bff6bc 100644
> --- a/tcp.c
> +++ b/tcp.c
> @@ -1644,6 +1644,8 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> } else if (!(flags & RST)) {
> flags |= ACK;
> *optlen = 0;
> + } else {
> + *optlen = 0;
> }
>
> th->doff = (sizeof(*th) + *optlen) / 4;
> @@ -1695,8 +1697,14 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
>
> ret = tcp_prepare_flags(c, conn, flags, &payload->th,
> payload->opts, &optlen);
> - if (ret <= 0)
> + if (ret <= 0) {
> + if (CONN_V4(conn))
> + tcp4_flags_used--;
> + else
> + tcp6_flags_used--;
> +
> return ret;
> + }
>
> l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
> conn->seq_to_tap);
> @@ -1738,7 +1746,7 @@ static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn)
> if (conn->events == CLOSED)
> return;
>
> - if (!tcp_send_flag(c, conn, RST))
> + if (tcp_send_flag(c, conn, RST) >= 0)
> conn_event(c, conn, CLOSED);
> }
>
> @@ -2111,7 +2119,7 @@ static void tcp_conn_from_tap(struct ctx *c, sa_family_t af,
> } else {
> tcp_get_sndbuf(conn);
>
> - if (tcp_send_flag(c, conn, SYN | ACK))
> + if (tcp_send_flag(c, conn, SYN | ACK) < 0)
> goto cancel;
>
> conn_event(c, conn, TAP_SYN_ACK_SENT);
> @@ -2282,9 +2290,11 @@ static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn)
>
> if (!len) {
> if ((conn->events & (SOCK_FIN_RCVD | TAP_FIN_SENT)) == SOCK_FIN_RCVD) {
> - if ((ret = tcp_send_flag(c, conn, FIN | ACK))) {
> + int rc = tcp_send_flag(c, conn, FIN | ACK);
> +
> + if (rc < 0) {
> tcp_rst(c, conn);
> - return ret;
> + return rc;
> }
>
> conn_event(c, conn, TAP_FIN_SENT);
> @@ -2716,7 +2726,7 @@ static void tcp_connect_finish(struct ctx *c, struct tcp_tap_conn *conn)
> return;
> }
>
> - if (tcp_send_flag(c, conn, SYN | ACK))
> + if (tcp_send_flag(c, conn, SYN | ACK) < 0)
> return;
>
> conn_event(c, conn, TAP_SYN_ACK_SENT);
>
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 6:07 ` Stefano Brivio
@ 2024-06-13 8:24 ` Laurent Vivier
2024-06-13 10:14 ` Stefano Brivio
0 siblings, 1 reply; 25+ messages in thread
From: Laurent Vivier @ 2024-06-13 8:24 UTC (permalink / raw)
To: Stefano Brivio; +Cc: passt-dev, David Gibson
Hi,
I think the problem can be because tcp_l2_buf_fill_headers() has been moved out of
tcp_prepare_flags() and so moved after:
if (th->fin || th->syn)
conn->seq_to_tap++;
and con->seq_to_tap is also a parameter of tcp_l2_buf_fill_headers(). So it is increased
before and not after.
Could you try:
diff --git a/tcp.c b/tcp.c
index 6800209d4122..647f42291fcf 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1607,6 +1607,7 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
return 0;
+ *optlen = 0;
if (flags & SYN) {
int mss;
@@ -1643,7 +1644,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
*data++ = conn->ws_to_tap;
} else if (!(flags & RST)) {
flags |= ACK;
- *optlen = 0;
}
th->doff = (sizeof(*th) + *optlen) / 4;
@@ -1663,10 +1663,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
if (th->fin)
conn_flag(c, conn, ACK_FROM_TAP_DUE);
- /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
- if (th->fin || th->syn)
- conn->seq_to_tap++;
-
return 1;
}
@@ -1702,6 +1698,10 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn,
int flags)
conn->seq_to_tap);
iov[TCP_IOV_PAYLOAD].iov_len = l4len;
+ /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
+ if (th->fin || th->syn)
+ conn->seq_to_tap++;
+
if (flags & DUP_ACK) {
struct iovec *dup_iov;
int i;
Thanks,
Laurent
On 13/06/2024 08:07, Stefano Brivio wrote:
> On Wed, 12 Jun 2024 23:22:10 +0200
> Stefano Brivio <sbrivio@redhat.com> wrote:
>
>> I couldn't find out why this patch breaks the the pasta_podman/bats
>> test, yet, that is:
>>
>> not ok 19 [505] Single TCP port forwarding, IPv4, tap
>> # (from function `bail-now' in file test/podman/test/system/helpers.bash, line 235,
>> # from function `assert' in file test/podman/test/system/helpers.bash, line 929,
>> # from function `pasta_test_do' in file test/podman/test/system/505-networking-pasta.bats, line 239,
>> # in test file test/podman/test/system/505-networking-pasta.bats, line 472)
>> # `pasta_test_do' failed
>> #
>> # [22:54:18.306131353] $ test/podman/bin/podman rm -t 0 --all --force --ignore
>> #
>> # [22:54:18.367462243] $ test/podman/bin/podman ps --all --external --format {{.ID}} {{.Names}}
>> #
>> # [22:54:18.394935392] $ test/podman/bin/podman images --all --format {{.Repository}}:{{.Tag}} {{.ID}}
>> # [22:54:18.419773379] quay.io/libpod/testimage:20240123 1f6acd4c4a1d
>> #
>> # [22:54:19.246631856] $ test/podman/bin/podman info --format {{.Host.Pasta.Executable}}
>> # [22:54:20.084392405] /home/sbrivio/passt/pasta
>> #
>> # [22:54:20.167980222] $ test/podman/bin/podman run --net=pasta -p [88.198.0.164]:5727:5727/tcp quay.io/libpod/testimage:20240123 sh -c for port in $(seq 5727 5727); do socat -u TCP4-LISTEN:${port},bind=[88.198.0.164] STDOUT & done; wait
>> # [22:54:37.256040883] x2024/06/12 20:54:37 socat[3] E read(6, 0x7fe675cd6000, 8192): Connection reset by peer
>> # #/vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
>> # #| FAIL: Mismatch between data sent and received
>> # #| expected: = x
>> # #| actual: x2024/06/12 20:54:37 socat\[3\] E read\(6\, 0x7fe675cd6000\, 8192\): Connection reset by peer
>> # #\^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>
>> meaning that the data transfer is actually fine, but we reset the
>> connection instead of an orderly shutdown.
>>
>> I found a few issues while looking for that:
>>
>> On Wed, 12 Jun 2024 17:47:27 +0200
>> Laurent Vivier <lvivier@redhat.com> wrote:
>>
>>> This commit isolates the internal data structure management used for storing
>>> data (e.g., tcp4_l2_flags_iov[], tcp6_l2_flags_iov[], tcp4_flags_ip[],
>>> tcp4_flags[], ...) from the tcp_send_flag() function. The extracted
>>> functionality is relocated to a new function named tcp_fill_flag_header().
>>>
>>> tcp_fill_flag_header() is now a generic function that accepts parameters such
>>> as struct tcphdr and a data pointer. tcp_send_flag() utilizes this parameter to
>>> pass memory pointers from tcp4_l2_flags_iov[] and tcp6_l2_flags_iov[].
>>>
>>> This separation sets the stage for utilizing tcp_fill_flag_header() to
>>> set the memory provided by the guest via vhost-user in future developments.
>>>
>>> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
>>> ---
>>>
>>> Notes:
>>> v6:
>>> - rename tcp_fill_flag_header() to tcp_prepare_flags()
>>> - set optlen to 0 in tcp_prepare_flags()
>>>
>>> v5:
>>> - use tcp_fill_flag_header() rather than tcp_fill_headers4() and
>>> tcp_fill_headers6().
>>>
>>> tcp.c | 72 +++++++++++++++++++++++++++++++++++++++--------------------
>>> 1 file changed, 48 insertions(+), 24 deletions(-)
>>>
>>> diff --git a/tcp.c b/tcp.c
>>> index dd8d46e08628..6800209d4122 100644
>>> --- a/tcp.c
>>> +++ b/tcp.c
>>> @@ -1567,24 +1567,25 @@ static void tcp_update_seqack_from_tap(const struct ctx *c,
>>> }
>>>
>>> /**
>>> - * tcp_send_flag() - Send segment with flags to tap (no payload)
>>> + * tcp_prepare_flags() - Prepare header for flags-only segment (no payload)
>>> * @c: Execution context
>>> * @conn: Connection pointer
>>> * @flags: TCP flags: if not set, send segment only if ACK is due
>>> + * @th: TCP header to update
>>> + * @data: buffer to store TCP option
>>> + * @optlen: size of the TCP option buffer (output parameter)
>>> *
>>> - * Return: negative error code on connection reset, 0 otherwise
>>> + * Return: < 0 error code on connection reset,
>>> + * 0 if there is no flag to send
>>> + * 1 otherwise
>>
>> This is often called with if (tcp_send_flag(...)) or
>> if (!tcp_send_flag(...)). Those need to be replaced with
>> if (tcp_send_flag(...) < 0) or if (tcp_send_flag(...) >= 0) in the
>> callers.
>
> Ah, no, sorry, you already took care of this in the new
> tcp_send_flag(). Then there must be something else...
>
>>> */
>>> -static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
>>> +static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
>>> + int flags, struct tcphdr *th, char *data,
>>> + size_t *optlen)
>>> {
>>> - struct tcp_flags_t *payload;
>>> struct tcp_info tinfo = { 0 };
>>> socklen_t sl = sizeof(tinfo);
>>> int s = conn->sock;
>>> - size_t optlen = 0;
>>> - struct tcphdr *th;
>>> - struct iovec *iov;
>>> - size_t l4len;
>>> - char *data;
>>>
>>> if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap) &&
>>> !flags && conn->wnd_to_tap)
>>> @@ -1606,20 +1607,11 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
>>> if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
>>> return 0;
>>>
>>> - if (CONN_V4(conn))
>>> - iov = tcp4_l2_flags_iov[tcp4_flags_used++];
>>> - else
>>> - iov = tcp6_l2_flags_iov[tcp6_flags_used++];
>>> -
>>> - payload = iov[TCP_IOV_PAYLOAD].iov_base;
>>> - th = &payload->th;
>>> - data = payload->opts;
>>> -
>>> if (flags & SYN) {
>>> int mss;
>>>
>>> /* Options: MSS, NOP and window scale (8 bytes) */
>>> - optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
>>> + *optlen = OPT_MSS_LEN + 1 + OPT_WS_LEN;
>>>
>>> *data++ = OPT_MSS;
>>> *data++ = OPT_MSS_LEN;
>>> @@ -1651,19 +1643,16 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
>>> *data++ = conn->ws_to_tap;
>>> } else if (!(flags & RST)) {
>>> flags |= ACK;
>>> + *optlen = 0;
>>
>> *optlen also needs to be set to 0 if (flags & RST), say:
>>
>> } else {
>> *optlen = 0;
>>
>> if (!(flags & RST))
>> flags |= ACK;
>> }
>>
>>> }
>>>
>>> - th->doff = (sizeof(*th) + optlen) / 4;
>>> + th->doff = (sizeof(*th) + *optlen) / 4;
>>>
>>> th->ack = !!(flags & ACK);
>>> th->rst = !!(flags & RST);
>>> th->syn = !!(flags & SYN);
>>> th->fin = !!(flags & FIN);
>>>
>>> - l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
>>> - conn->seq_to_tap);
>>> - iov[TCP_IOV_PAYLOAD].iov_len = l4len;
>>> -
>>> if (th->ack) {
>>> if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap))
>>> conn_flag(c, conn, ~ACK_TO_TAP_DUE);
>>> @@ -1678,6 +1667,41 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
>>> if (th->fin || th->syn)
>>> conn->seq_to_tap++;
>>>
>>> + return 1;
>>> +}
>>> +
>>> +/**
>>> + * tcp_send_flag() - Send segment with flags to tap (no payload)
>>> + * @c: Execution context
>>> + * @conn: Connection pointer
>>> + * @flags: TCP flags: if not set, send segment only if ACK is due
>>> + *
>>> + * Return: negative error code on connection reset, 0 otherwise
>>> + */
>>> +static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
>>> +{
>>> + struct tcp_flags_t *payload;
>>> + struct iovec *iov;
>>> + size_t optlen;
>>> + size_t l4len;
>>> + int ret;
>>> +
>>> + if (CONN_V4(conn))
>>> + iov = tcp4_l2_flags_iov[tcp4_flags_used++];
>>> + else
>>> + iov = tcp6_l2_flags_iov[tcp6_flags_used++];
>>
>> We increase the counters here, but we don't decrease them back if we
>> hit if (ret <= 0) return ret; later.
>>
>>> +
>>> + payload = iov[TCP_IOV_PAYLOAD].iov_base;
>>> +
>>> + ret = tcp_prepare_flags(c, conn, flags, &payload->th,
>>> + payload->opts, &optlen);
>>> + if (ret <= 0)
>>> + return ret;
>>> +
>>> + l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
>>> + conn->seq_to_tap);
>>> + iov[TCP_IOV_PAYLOAD].iov_len = l4len;
>>> +
>>> if (flags & DUP_ACK) {
>>> struct iovec *dup_iov;
>>> int i;
>>
>> Here's the diff I have so far, I'm not necessarily recommending any of
>> that, it was just a quick try:
>>
>> diff --git a/tcp.c b/tcp.c
>> index 6800209..6bff6bc 100644
>> --- a/tcp.c
>> +++ b/tcp.c
>> @@ -1644,6 +1644,8 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
>> } else if (!(flags & RST)) {
>> flags |= ACK;
>> *optlen = 0;
>> + } else {
>> + *optlen = 0;
>> }
>>
>> th->doff = (sizeof(*th) + *optlen) / 4;
>> @@ -1695,8 +1697,14 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
>>
>> ret = tcp_prepare_flags(c, conn, flags, &payload->th,
>> payload->opts, &optlen);
>> - if (ret <= 0)
>> + if (ret <= 0) {
>> + if (CONN_V4(conn))
>> + tcp4_flags_used--;
>> + else
>> + tcp6_flags_used--;
>> +
>> return ret;
>> + }
>>
>> l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
>> conn->seq_to_tap);
>> @@ -1738,7 +1746,7 @@ static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn)
>> if (conn->events == CLOSED)
>> return;
>>
>> - if (!tcp_send_flag(c, conn, RST))
>> + if (tcp_send_flag(c, conn, RST) >= 0)
>> conn_event(c, conn, CLOSED);
>> }
>>
>> @@ -2111,7 +2119,7 @@ static void tcp_conn_from_tap(struct ctx *c, sa_family_t af,
>> } else {
>> tcp_get_sndbuf(conn);
>>
>> - if (tcp_send_flag(c, conn, SYN | ACK))
>> + if (tcp_send_flag(c, conn, SYN | ACK) < 0)
>> goto cancel;
>>
>> conn_event(c, conn, TAP_SYN_ACK_SENT);
>> @@ -2282,9 +2290,11 @@ static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn)
>>
>> if (!len) {
>> if ((conn->events & (SOCK_FIN_RCVD | TAP_FIN_SENT)) == SOCK_FIN_RCVD) {
>> - if ((ret = tcp_send_flag(c, conn, FIN | ACK))) {
>> + int rc = tcp_send_flag(c, conn, FIN | ACK);
>> +
>> + if (rc < 0) {
>> tcp_rst(c, conn);
>> - return ret;
>> + return rc;
>> }
>>
>> conn_event(c, conn, TAP_FIN_SENT);
>> @@ -2716,7 +2726,7 @@ static void tcp_connect_finish(struct ctx *c, struct tcp_tap_conn *conn)
>> return;
>> }
>>
>> - if (tcp_send_flag(c, conn, SYN | ACK))
>> + if (tcp_send_flag(c, conn, SYN | ACK) < 0)
>> return;
>>
>> conn_event(c, conn, TAP_SYN_ACK_SENT);
>>
>
^ permalink raw reply related [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 8:24 ` Laurent Vivier
@ 2024-06-13 10:14 ` Stefano Brivio
2024-06-13 10:22 ` Laurent Vivier
0 siblings, 1 reply; 25+ messages in thread
From: Stefano Brivio @ 2024-06-13 10:14 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
On Thu, 13 Jun 2024 10:24:11 +0200
Laurent Vivier <lvivier@redhat.com> wrote:
> Hi,
>
> I think the problem can be because tcp_l2_buf_fill_headers() has been moved out of
> tcp_prepare_flags() and so moved after:
>
> if (th->fin || th->syn)
> conn->seq_to_tap++;
>
> and con->seq_to_tap is also a parameter of tcp_l2_buf_fill_headers(). So it is increased
> before and not after.
>
> Could you try:
>
> diff --git a/tcp.c b/tcp.c
> index 6800209d4122..647f42291fcf 100644
> --- a/tcp.c
> +++ b/tcp.c
> @@ -1607,6 +1607,7 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
> return 0;
>
> + *optlen = 0;
> if (flags & SYN) {
> int mss;
>
> @@ -1643,7 +1644,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> *data++ = conn->ws_to_tap;
> } else if (!(flags & RST)) {
> flags |= ACK;
> - *optlen = 0;
> }
>
> th->doff = (sizeof(*th) + *optlen) / 4;
> @@ -1663,10 +1663,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> if (th->fin)
> conn_flag(c, conn, ACK_FROM_TAP_DUE);
>
> - /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
> - if (th->fin || th->syn)
> - conn->seq_to_tap++;
> -
> return 1;
> }
>
> @@ -1702,6 +1698,10 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn,
> int flags)
> conn->seq_to_tap);
> iov[TCP_IOV_PAYLOAD].iov_len = l4len;
>
> + /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
> + if (th->fin || th->syn)
> + conn->seq_to_tap++;
> +
> if (flags & DUP_ACK) {
> struct iovec *dup_iov;
> int i;
Ah, yes, good catch, I missed this one! It works. Note that it needs to
be:
if ((flags & FIN) || (flags & SYN))
...
because we don't have a TCP header there, yet.
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 10:14 ` Stefano Brivio
@ 2024-06-13 10:22 ` Laurent Vivier
2024-06-13 10:49 ` Stefano Brivio
0 siblings, 1 reply; 25+ messages in thread
From: Laurent Vivier @ 2024-06-13 10:22 UTC (permalink / raw)
To: Stefano Brivio; +Cc: passt-dev, David Gibson
On 13/06/2024 12:14, Stefano Brivio wrote:
> On Thu, 13 Jun 2024 10:24:11 +0200
> Laurent Vivier <lvivier@redhat.com> wrote:
>
>> Hi,
>>
>> I think the problem can be because tcp_l2_buf_fill_headers() has been moved out of
>> tcp_prepare_flags() and so moved after:
>>
>> if (th->fin || th->syn)
>> conn->seq_to_tap++;
>>
>> and con->seq_to_tap is also a parameter of tcp_l2_buf_fill_headers(). So it is increased
>> before and not after.
>>
>> Could you try:
>>
>> diff --git a/tcp.c b/tcp.c
>> index 6800209d4122..647f42291fcf 100644
>> --- a/tcp.c
>> +++ b/tcp.c
>> @@ -1607,6 +1607,7 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
>> if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
>> return 0;
>>
>> + *optlen = 0;
>> if (flags & SYN) {
>> int mss;
>>
>> @@ -1643,7 +1644,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
>> *data++ = conn->ws_to_tap;
>> } else if (!(flags & RST)) {
>> flags |= ACK;
>> - *optlen = 0;
>> }
>>
>> th->doff = (sizeof(*th) + *optlen) / 4;
>> @@ -1663,10 +1663,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
>> if (th->fin)
>> conn_flag(c, conn, ACK_FROM_TAP_DUE);
>>
>> - /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
>> - if (th->fin || th->syn)
>> - conn->seq_to_tap++;
>> -
>> return 1;
>> }
>>
>> @@ -1702,6 +1698,10 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn,
>> int flags)
>> conn->seq_to_tap);
>> iov[TCP_IOV_PAYLOAD].iov_len = l4len;
>>
>> + /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
>> + if (th->fin || th->syn)
>> + conn->seq_to_tap++;
>> +
>> if (flags & DUP_ACK) {
>> struct iovec *dup_iov;
>> int i;
>
> Ah, yes, good catch, I missed this one! It works. Note that it needs to
> be:
>
> if ((flags & FIN) || (flags & SYN))
> ...
>
> because we don't have a TCP header there, yet.
>
I'm wondering if I can do:
+ seq = conn->seq_to_tap;
ret = tcp_prepare_flags(c, conn, flags, &payload->th,
payload->opts, &optlen);
if (ret <= 0)
return ret;
l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
- conn->seq_to_tap);
+ seq);
to keep the flags in tcp_prepare_flags()?
Thanks,
Laurent
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 10:22 ` Laurent Vivier
@ 2024-06-13 10:49 ` Stefano Brivio
2024-06-13 10:58 ` Laurent Vivier
0 siblings, 1 reply; 25+ messages in thread
From: Stefano Brivio @ 2024-06-13 10:49 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
On Thu, 13 Jun 2024 12:22:54 +0200
Laurent Vivier <lvivier@redhat.com> wrote:
> On 13/06/2024 12:14, Stefano Brivio wrote:
> > On Thu, 13 Jun 2024 10:24:11 +0200
> > Laurent Vivier <lvivier@redhat.com> wrote:
> >
> >> Hi,
> >>
> >> I think the problem can be because tcp_l2_buf_fill_headers() has been moved out of
> >> tcp_prepare_flags() and so moved after:
> >>
> >> if (th->fin || th->syn)
> >> conn->seq_to_tap++;
> >>
> >> and con->seq_to_tap is also a parameter of tcp_l2_buf_fill_headers(). So it is increased
> >> before and not after.
> >>
> >> Could you try:
> >>
> >> diff --git a/tcp.c b/tcp.c
> >> index 6800209d4122..647f42291fcf 100644
> >> --- a/tcp.c
> >> +++ b/tcp.c
> >> @@ -1607,6 +1607,7 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> >> if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
> >> return 0;
> >>
> >> + *optlen = 0;
> >> if (flags & SYN) {
> >> int mss;
> >>
> >> @@ -1643,7 +1644,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> >> *data++ = conn->ws_to_tap;
> >> } else if (!(flags & RST)) {
> >> flags |= ACK;
> >> - *optlen = 0;
> >> }
> >>
> >> th->doff = (sizeof(*th) + *optlen) / 4;
> >> @@ -1663,10 +1663,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> >> if (th->fin)
> >> conn_flag(c, conn, ACK_FROM_TAP_DUE);
> >>
> >> - /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
> >> - if (th->fin || th->syn)
> >> - conn->seq_to_tap++;
> >> -
> >> return 1;
> >> }
> >>
> >> @@ -1702,6 +1698,10 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn,
> >> int flags)
> >> conn->seq_to_tap);
> >> iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> >>
> >> + /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
> >> + if (th->fin || th->syn)
> >> + conn->seq_to_tap++;
> >> +
> >> if (flags & DUP_ACK) {
> >> struct iovec *dup_iov;
> >> int i;
> >
> > Ah, yes, good catch, I missed this one! It works. Note that it needs to
> > be:
> >
> > if ((flags & FIN) || (flags & SYN))
> > ...
> >
> > because we don't have a TCP header there, yet.
> >
>
> I'm wondering if I can do:
>
> + seq = conn->seq_to_tap;
> ret = tcp_prepare_flags(c, conn, flags, &payload->th,
> payload->opts, &optlen);
> if (ret <= 0)
> return ret;
>
> l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
> - conn->seq_to_tap);
> + seq);
>
> to keep the flags in tcp_prepare_flags()?
Maybe, yes. I don't really have a strong preference. On the other hand
tcp_send_flag() has to deal with the DUP_ACK case on its own anyway.
But sure, this version would be a bit cleaner, and if vhost-user code
will then want to call tcp_prepare_flags() without tcp_send_flag(),
it avoids code duplication, I guess?
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 10:49 ` Stefano Brivio
@ 2024-06-13 10:58 ` Laurent Vivier
0 siblings, 0 replies; 25+ messages in thread
From: Laurent Vivier @ 2024-06-13 10:58 UTC (permalink / raw)
To: Stefano Brivio; +Cc: passt-dev, David Gibson
On 13/06/2024 12:49, Stefano Brivio wrote:
> On Thu, 13 Jun 2024 12:22:54 +0200
> Laurent Vivier <lvivier@redhat.com> wrote:
>
>> On 13/06/2024 12:14, Stefano Brivio wrote:
>>> On Thu, 13 Jun 2024 10:24:11 +0200
>>> Laurent Vivier <lvivier@redhat.com> wrote:
>>>
>>>> Hi,
>>>>
>>>> I think the problem can be because tcp_l2_buf_fill_headers() has been moved out of
>>>> tcp_prepare_flags() and so moved after:
>>>>
>>>> if (th->fin || th->syn)
>>>> conn->seq_to_tap++;
>>>>
>>>> and con->seq_to_tap is also a parameter of tcp_l2_buf_fill_headers(). So it is increased
>>>> before and not after.
>>>>
>>>> Could you try:
>>>>
>>>> diff --git a/tcp.c b/tcp.c
>>>> index 6800209d4122..647f42291fcf 100644
>>>> --- a/tcp.c
>>>> +++ b/tcp.c
>>>> @@ -1607,6 +1607,7 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
>>>> if (!tcp_update_seqack_wnd(c, conn, flags, &tinfo) && !flags)
>>>> return 0;
>>>>
>>>> + *optlen = 0;
>>>> if (flags & SYN) {
>>>> int mss;
>>>>
>>>> @@ -1643,7 +1644,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
>>>> *data++ = conn->ws_to_tap;
>>>> } else if (!(flags & RST)) {
>>>> flags |= ACK;
>>>> - *optlen = 0;
>>>> }
>>>>
>>>> th->doff = (sizeof(*th) + *optlen) / 4;
>>>> @@ -1663,10 +1663,6 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
>>>> if (th->fin)
>>>> conn_flag(c, conn, ACK_FROM_TAP_DUE);
>>>>
>>>> - /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
>>>> - if (th->fin || th->syn)
>>>> - conn->seq_to_tap++;
>>>> -
>>>> return 1;
>>>> }
>>>>
>>>> @@ -1702,6 +1698,10 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn,
>>>> int flags)
>>>> conn->seq_to_tap);
>>>> iov[TCP_IOV_PAYLOAD].iov_len = l4len;
>>>>
>>>> + /* RFC 793, 3.1: "[...] and the first data octet is ISN+1." */
>>>> + if (th->fin || th->syn)
>>>> + conn->seq_to_tap++;
>>>> +
>>>> if (flags & DUP_ACK) {
>>>> struct iovec *dup_iov;
>>>> int i;
>>>
>>> Ah, yes, good catch, I missed this one! It works. Note that it needs to
>>> be:
>>>
>>> if ((flags & FIN) || (flags & SYN))
>>> ...
>>>
>>> because we don't have a TCP header there, yet.
>>>
>>
>> I'm wondering if I can do:
>>
>> + seq = conn->seq_to_tap;
>> ret = tcp_prepare_flags(c, conn, flags, &payload->th,
>> payload->opts, &optlen);
>> if (ret <= 0)
>> return ret;
>>
>> l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
>> - conn->seq_to_tap);
>> + seq);
>>
>> to keep the flags in tcp_prepare_flags()?
>
> Maybe, yes. I don't really have a strong preference. On the other hand
> tcp_send_flag() has to deal with the DUP_ACK case on its own anyway.
>
> But sure, this version would be a bit cleaner, and if vhost-user code
> will then want to call tcp_prepare_flags() without tcp_send_flag(),
> it avoids code duplication, I guess?
>
Yes.
I prepare a new version of the series with the changes.
Thanks,
Laurent
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-12 21:22 ` Stefano Brivio
2024-06-13 6:07 ` Stefano Brivio
@ 2024-06-13 7:31 ` Laurent Vivier
2024-06-13 9:35 ` Stefano Brivio
1 sibling, 1 reply; 25+ messages in thread
From: Laurent Vivier @ 2024-06-13 7:31 UTC (permalink / raw)
To: Stefano Brivio; +Cc: passt-dev, David Gibson
On 12/06/2024 23:22, Stefano Brivio wrote:
> I couldn't find out why this patch breaks the the pasta_podman/bats
> test, yet, that is:
>
> not ok 19 [505] Single TCP port forwarding, IPv4, tap
> # (from function `bail-now' in file test/podman/test/system/helpers.bash, line 235,
> # from function `assert' in file test/podman/test/system/helpers.bash, line 929,
> # from function `pasta_test_do' in file test/podman/test/system/505-networking-pasta.bats, line 239,
> # in test file test/podman/test/system/505-networking-pasta.bats, line 472)
> # `pasta_test_do' failed
> #
> # [22:54:18.306131353] $ test/podman/bin/podman rm -t 0 --all --force --ignore
> #
> # [22:54:18.367462243] $ test/podman/bin/podman ps --all --external --format {{.ID}} {{.Names}}
> #
> # [22:54:18.394935392] $ test/podman/bin/podman images --all --format {{.Repository}}:{{.Tag}} {{.ID}}
> # [22:54:18.419773379] quay.io/libpod/testimage:20240123 1f6acd4c4a1d
> #
> # [22:54:19.246631856] $ test/podman/bin/podman info --format {{.Host.Pasta.Executable}}
> # [22:54:20.084392405] /home/sbrivio/passt/pasta
> #
> # [22:54:20.167980222] $ test/podman/bin/podman run --net=pasta -p [88.198.0.164]:5727:5727/tcp quay.io/libpod/testimage:20240123 sh -c for port in $(seq 5727 5727); do socat -u TCP4-LISTEN:${port},bind=[88.198.0.164] STDOUT & done; wait
> # [22:54:37.256040883] x2024/06/12 20:54:37 socat[3] E read(6, 0x7fe675cd6000, 8192): Connection reset by peer
> # #/vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
> # #| FAIL: Mismatch between data sent and received
> # #| expected: = x
> # #| actual: x2024/06/12 20:54:37 socat\[3\] E read\(6\, 0x7fe675cd6000\, 8192\): Connection reset by peer
> # #\^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
> meaning that the data transfer is actually fine, but we reset the
> connection instead of an orderly shutdown.
>
How do you run this test?
Thanks,
Laurent
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 7:31 ` Laurent Vivier
@ 2024-06-13 9:35 ` Stefano Brivio
2024-06-13 14:36 ` David Gibson
0 siblings, 1 reply; 25+ messages in thread
From: Stefano Brivio @ 2024-06-13 9:35 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
On Thu, 13 Jun 2024 09:31:44 +0200
Laurent Vivier <lvivier@redhat.com> wrote:
> On 12/06/2024 23:22, Stefano Brivio wrote:
> > I couldn't find out why this patch breaks the the pasta_podman/bats
> > test, yet, that is:
> >
> > not ok 19 [505] Single TCP port forwarding, IPv4, tap
> > # (from function `bail-now' in file test/podman/test/system/helpers.bash, line 235,
> > # from function `assert' in file test/podman/test/system/helpers.bash, line 929,
> > # from function `pasta_test_do' in file test/podman/test/system/505-networking-pasta.bats, line 239,
> > # in test file test/podman/test/system/505-networking-pasta.bats, line 472)
> > # `pasta_test_do' failed
> > #
> > # [22:54:18.306131353] $ test/podman/bin/podman rm -t 0 --all --force --ignore
> > #
> > # [22:54:18.367462243] $ test/podman/bin/podman ps --all --external --format {{.ID}} {{.Names}}
> > #
> > # [22:54:18.394935392] $ test/podman/bin/podman images --all --format {{.Repository}}:{{.Tag}} {{.ID}}
> > # [22:54:18.419773379] quay.io/libpod/testimage:20240123 1f6acd4c4a1d
> > #
> > # [22:54:19.246631856] $ test/podman/bin/podman info --format {{.Host.Pasta.Executable}}
> > # [22:54:20.084392405] /home/sbrivio/passt/pasta
> > #
> > # [22:54:20.167980222] $ test/podman/bin/podman run --net=pasta -p [88.198.0.164]:5727:5727/tcp quay.io/libpod/testimage:20240123 sh -c for port in $(seq 5727 5727); do socat -u TCP4-LISTEN:${port},bind=[88.198.0.164] STDOUT & done; wait
> > # [22:54:37.256040883] x2024/06/12 20:54:37 socat[3] E read(6, 0x7fe675cd6000, 8192): Connection reset by peer
> > # #/vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
> > # #| FAIL: Mismatch between data sent and received
> > # #| expected: = x
> > # #| actual: x2024/06/12 20:54:37 socat\[3\] E read\(6\, 0x7fe675cd6000\, 8192\): Connection reset by peer
> > # #\^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> >
> > meaning that the data transfer is actually fine, but we reset the
> > connection instead of an orderly shutdown.
>
> How do you run this test?
It's in the test suite, see test/README.md. Make sure you have a local
build of Podman with 'make podman' under test/. You can also skip other
tests by commenting the rest out in test/run, then do ./run from test/.
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 9:35 ` Stefano Brivio
@ 2024-06-13 14:36 ` David Gibson
0 siblings, 0 replies; 25+ messages in thread
From: David Gibson @ 2024-06-13 14:36 UTC (permalink / raw)
To: Stefano Brivio; +Cc: Laurent Vivier, passt-dev
[-- Attachment #1: Type: text/plain, Size: 3005 bytes --]
On Thu, Jun 13, 2024 at 11:35:53AM +0200, Stefano Brivio wrote:
> On Thu, 13 Jun 2024 09:31:44 +0200
> Laurent Vivier <lvivier@redhat.com> wrote:
>
> > On 12/06/2024 23:22, Stefano Brivio wrote:
> > > I couldn't find out why this patch breaks the the pasta_podman/bats
> > > test, yet, that is:
> > >
> > > not ok 19 [505] Single TCP port forwarding, IPv4, tap
> > > # (from function `bail-now' in file test/podman/test/system/helpers.bash, line 235,
> > > # from function `assert' in file test/podman/test/system/helpers.bash, line 929,
> > > # from function `pasta_test_do' in file test/podman/test/system/505-networking-pasta.bats, line 239,
> > > # in test file test/podman/test/system/505-networking-pasta.bats, line 472)
> > > # `pasta_test_do' failed
> > > #
> > > # [22:54:18.306131353] $ test/podman/bin/podman rm -t 0 --all --force --ignore
> > > #
> > > # [22:54:18.367462243] $ test/podman/bin/podman ps --all --external --format {{.ID}} {{.Names}}
> > > #
> > > # [22:54:18.394935392] $ test/podman/bin/podman images --all --format {{.Repository}}:{{.Tag}} {{.ID}}
> > > # [22:54:18.419773379] quay.io/libpod/testimage:20240123 1f6acd4c4a1d
> > > #
> > > # [22:54:19.246631856] $ test/podman/bin/podman info --format {{.Host.Pasta.Executable}}
> > > # [22:54:20.084392405] /home/sbrivio/passt/pasta
> > > #
> > > # [22:54:20.167980222] $ test/podman/bin/podman run --net=pasta -p [88.198.0.164]:5727:5727/tcp quay.io/libpod/testimage:20240123 sh -c for port in $(seq 5727 5727); do socat -u TCP4-LISTEN:${port},bind=[88.198.0.164] STDOUT & done; wait
> > > # [22:54:37.256040883] x2024/06/12 20:54:37 socat[3] E read(6, 0x7fe675cd6000, 8192): Connection reset by peer
> > > # #/vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
> > > # #| FAIL: Mismatch between data sent and received
> > > # #| expected: = x
> > > # #| actual: x2024/06/12 20:54:37 socat\[3\] E read\(6\, 0x7fe675cd6000\, 8192\): Connection reset by peer
> > > # #\^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > >
> > > meaning that the data transfer is actually fine, but we reset the
> > > connection instead of an orderly shutdown.
> >
> > How do you run this test?
>
> It's in the test suite, see test/README.md. Make sure you have a local
> build of Podman with 'make podman' under test/.
Running 'make' in test/ will clone/update and build podman/
> You can also skip other
> tests by commenting the rest out in test/run, then do ./run from test/.
You can also run them manually by going into test/system in the podman
tree, and running
CONTAINERS_HELPER_BINARY_DIR=/path/to/passt bats 505-networking-pasta.bats
With either option you'll need bats installed (the Fedora package is
just 'bats')
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH v6 2/8] tcp: move buffers management functions to their own file
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
2024-06-12 15:47 ` [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag() Laurent Vivier
@ 2024-06-12 15:47 ` Laurent Vivier
2024-06-12 15:54 ` Stefano Brivio
2024-06-12 15:47 ` [PATCH v6 3/8] tap: refactor packets handling functions Laurent Vivier
` (6 subsequent siblings)
8 siblings, 1 reply; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 15:47 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Move all the TCP parts using internal buffers to tcp_buf.c
and keep generic TCP management functions in tcp.c.
Add tcp_internal.h to export needed functions from tcp.c and
tcp_buf.h from tcp_buf.c
With this change we can use existing TCP functions with a
different kind of memory storage as for instance the shared
memory provided by the guest via vhost-user.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
Notes:
v5:
- as we export now tcp_l2_buf_fill_headers() move
also enum tcp_iov_part to tcp_internal.h
v4:
- rename tcp_send_flag() and tcp_data_from_sock() to
tcp_buf_send_flag() and tcp_buf_data_from_sock()
Makefile | 5 +-
tcp.c | 562 ++-----------------------------------------------
tcp_buf.c | 513 ++++++++++++++++++++++++++++++++++++++++++++
tcp_buf.h | 16 ++
tcp_internal.h | 96 +++++++++
5 files changed, 648 insertions(+), 544 deletions(-)
create mode 100644 tcp_buf.c
create mode 100644 tcp_buf.h
create mode 100644 tcp_internal.h
diff --git a/Makefile b/Makefile
index e2180b599bdb..09fc461d087e 100644
--- a/Makefile
+++ b/Makefile
@@ -47,7 +47,7 @@ FLAGS += -DDUAL_STACK_SOCKETS=$(DUAL_STACK_SOCKETS)
PASST_SRCS = arch.c arp.c checksum.c conf.c dhcp.c dhcpv6.c flow.c fwd.c \
icmp.c igmp.c inany.c iov.c ip.c isolation.c lineread.c log.c mld.c \
ndp.c netlink.c packet.c passt.c pasta.c pcap.c pif.c tap.c tcp.c \
- tcp_splice.c udp.c util.c
+ tcp_buf.c tcp_splice.c udp.c util.c
QRAP_SRCS = qrap.c
SRCS = $(PASST_SRCS) $(QRAP_SRCS)
@@ -56,7 +56,8 @@ MANPAGES = passt.1 pasta.1 qrap.1
PASST_HEADERS = arch.h arp.h checksum.h conf.h dhcp.h dhcpv6.h flow.h fwd.h \
flow_table.h icmp.h icmp_flow.h inany.h iov.h ip.h isolation.h \
lineread.h log.h ndp.h netlink.h packet.h passt.h pasta.h pcap.h pif.h \
- siphash.h tap.h tcp.h tcp_conn.h tcp_splice.h udp.h util.h
+ siphash.h tap.h tcp.h tcp_buf.h tcp_conn.h tcp_internal.h tcp_splice.h \
+ udp.h util.h
HEADERS = $(PASST_HEADERS) seccomp.h
C := \#include <linux/tcp.h>\nstruct tcp_info x = { .tcpi_snd_wnd = 0 };
diff --git a/tcp.c b/tcp.c
index 6800209d4122..875e318c925b 100644
--- a/tcp.c
+++ b/tcp.c
@@ -302,28 +302,14 @@
#include "flow.h"
#include "flow_table.h"
-
-#define TCP_FRAMES_MEM 128
-#define TCP_FRAMES \
- (c->mode == MODE_PASST ? TCP_FRAMES_MEM : 1)
+#include "tcp_internal.h"
+#include "tcp_buf.h"
#define TCP_HASH_TABLE_LOAD 70 /* % */
#define TCP_HASH_TABLE_SIZE (FLOW_MAX * 100 / TCP_HASH_TABLE_LOAD)
-#define MAX_WS 8
-#define MAX_WINDOW (1 << (16 + (MAX_WS)))
-
/* MSS rounding: see SET_MSS() */
#define MSS_DEFAULT 536
-#define MSS4 ROUND_DOWN(IP_MAX_MTU - \
- sizeof(struct tcphdr) - \
- sizeof(struct iphdr), \
- sizeof(uint32_t))
-#define MSS6 ROUND_DOWN(IP_MAX_MTU - \
- sizeof(struct tcphdr) - \
- sizeof(struct ipv6hdr), \
- sizeof(uint32_t))
-
#define WINDOW_DEFAULT 14600 /* RFC 6928 */
#ifdef HAS_SND_WND
# define KERNEL_REPORTS_SND_WND(c) ((c)->tcp.kernel_snd_wnd)
@@ -345,33 +331,10 @@
*/
#define SOL_TCP IPPROTO_TCP
-#define SEQ_LE(a, b) ((b) - (a) < MAX_WINDOW)
-#define SEQ_LT(a, b) ((b) - (a) - 1 < MAX_WINDOW)
-#define SEQ_GE(a, b) ((a) - (b) < MAX_WINDOW)
-#define SEQ_GT(a, b) ((a) - (b) - 1 < MAX_WINDOW)
-
-#define FIN (1 << 0)
-#define SYN (1 << 1)
-#define RST (1 << 2)
-#define ACK (1 << 4)
-/* Flags for internal usage */
-#define DUP_ACK (1 << 5)
#define ACK_IF_NEEDED 0 /* See tcp_send_flag() */
-#define OPT_EOL 0
-#define OPT_NOP 1
-#define OPT_MSS 2
-#define OPT_MSS_LEN 4
-#define OPT_WS 3
-#define OPT_WS_LEN 3
-#define OPT_SACKP 4
-#define OPT_SACK 5
-#define OPT_TS 8
-
#define TAPSIDE(conn_) ((conn_)->f.pif[1] == PIF_TAP)
-#define CONN_V4(conn) (!!inany_v4(&(conn)->faddr))
-#define CONN_V6(conn) (!CONN_V4(conn))
#define CONN_IS_CLOSING(conn) \
(((conn)->events & ESTABLISHED) && \
((conn)->events & (SOCK_FIN_RCVD | TAP_FIN_RCVD)))
@@ -408,106 +371,7 @@ static int tcp_sock_ns [NUM_PORTS][IP_VERSIONS];
*/
static union inany_addr low_rtt_dst[LOW_RTT_TABLE_SIZE];
-/* Static buffers */
-/**
- * struct tcp_payload_t - TCP header and data to send segments with payload
- * @th: TCP header
- * @data: TCP data
- */
-struct tcp_payload_t {
- struct tcphdr th;
- uint8_t data[IP_MAX_MTU - sizeof(struct tcphdr)];
-#ifdef __AVX2__
-} __attribute__ ((packed, aligned(32))); /* For AVX2 checksum routines */
-#else
-} __attribute__ ((packed, aligned(__alignof__(unsigned int))));
-#endif
-
-/**
- * struct tcp_flags_t - TCP header and data to send zero-length
- * segments (flags)
- * @th: TCP header
- * @opts TCP options
- */
-struct tcp_flags_t {
- struct tcphdr th;
- char opts[OPT_MSS_LEN + OPT_WS_LEN + 1];
-#ifdef __AVX2__
-} __attribute__ ((packed, aligned(32)));
-#else
-} __attribute__ ((packed, aligned(__alignof__(unsigned int))));
-#endif
-
-/* Ethernet header for IPv4 frames */
-static struct ethhdr tcp4_eth_src;
-
-static struct tap_hdr tcp4_payload_tap_hdr[TCP_FRAMES_MEM];
-/* IPv4 headers */
-static struct iphdr tcp4_payload_ip[TCP_FRAMES_MEM];
-/* TCP segments with payload for IPv4 frames */
-static struct tcp_payload_t tcp4_payload[TCP_FRAMES_MEM];
-
-static_assert(MSS4 <= sizeof(tcp4_payload[0].data), "MSS4 is greater than 65516");
-
-/* References tracking the owner connection of frames in the tap outqueue */
-static struct tcp_tap_conn *tcp4_frame_conns[TCP_FRAMES_MEM];
-static unsigned int tcp4_payload_used;
-
-static struct tap_hdr tcp4_flags_tap_hdr[TCP_FRAMES_MEM];
-/* IPv4 headers for TCP segment without payload */
-static struct iphdr tcp4_flags_ip[TCP_FRAMES_MEM];
-/* TCP segments without payload for IPv4 frames */
-static struct tcp_flags_t tcp4_flags[TCP_FRAMES_MEM];
-
-static unsigned int tcp4_flags_used;
-
-/* Ethernet header for IPv6 frames */
-static struct ethhdr tcp6_eth_src;
-
-static struct tap_hdr tcp6_payload_tap_hdr[TCP_FRAMES_MEM];
-/* IPv6 headers */
-static struct ipv6hdr tcp6_payload_ip[TCP_FRAMES_MEM];
-/* TCP headers and data for IPv6 frames */
-static struct tcp_payload_t tcp6_payload[TCP_FRAMES_MEM];
-
-static_assert(MSS6 <= sizeof(tcp6_payload[0].data), "MSS6 is greater than 65516");
-
-/* References tracking the owner connection of frames in the tap outqueue */
-static struct tcp_tap_conn *tcp6_frame_conns[TCP_FRAMES_MEM];
-static unsigned int tcp6_payload_used;
-
-static struct tap_hdr tcp6_flags_tap_hdr[TCP_FRAMES_MEM];
-/* IPv6 headers for TCP segment without payload */
-static struct ipv6hdr tcp6_flags_ip[TCP_FRAMES_MEM];
-/* TCP segment without payload for IPv6 frames */
-static struct tcp_flags_t tcp6_flags[TCP_FRAMES_MEM];
-
-static unsigned int tcp6_flags_used;
-
-/* recvmsg()/sendmsg() data for tap */
-static char tcp_buf_discard [MAX_WINDOW];
-static struct iovec iov_sock [TCP_FRAMES_MEM + 1];
-
-/*
- * enum tcp_iov_parts - I/O vector parts for one TCP frame
- * @TCP_IOV_TAP tap backend specific header
- * @TCP_IOV_ETH Ethernet header
- * @TCP_IOV_IP IP (v4/v6) header
- * @TCP_IOV_PAYLOAD IP payload (TCP header + data)
- * @TCP_NUM_IOVS the number of entries in the iovec array
- */
-enum tcp_iov_parts {
- TCP_IOV_TAP = 0,
- TCP_IOV_ETH = 1,
- TCP_IOV_IP = 2,
- TCP_IOV_PAYLOAD = 3,
- TCP_NUM_IOVS
-};
-
-static struct iovec tcp4_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
-static struct iovec tcp6_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
-static struct iovec tcp4_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
-static struct iovec tcp6_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
+char tcp_buf_discard [MAX_WINDOW];
/* sendmsg() to socket */
static struct iovec tcp_iov [UIO_MAXIOV];
@@ -552,14 +416,6 @@ static uint32_t tcp_conn_epoll_events(uint8_t events, uint8_t conn_flags)
return EPOLLRDHUP;
}
-static void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
- unsigned long flag);
-#define conn_flag(c, conn, flag) \
- do { \
- flow_trace(conn, "flag at %s:%i", __func__, __LINE__); \
- conn_flag_do(c, conn, flag); \
- } while (0)
-
/**
* tcp_epoll_ctl() - Add/modify/delete epoll state from connection events
* @c: Execution context
@@ -671,8 +527,8 @@ static void tcp_timer_ctl(const struct ctx *c, struct tcp_tap_conn *conn)
* @conn: Connection pointer
* @flag: Flag to set, or ~flag to unset
*/
-static void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
- unsigned long flag)
+void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
+ unsigned long flag)
{
if (flag & (flag - 1)) {
int flag_index = fls(~flag);
@@ -722,8 +578,8 @@ static void tcp_hash_remove(const struct ctx *c,
* @conn: Connection pointer
* @event: Connection event
*/
-static void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
- unsigned long event)
+void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
+ unsigned long event)
{
int prev, new, num = fls(event);
@@ -771,12 +627,6 @@ static void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
tcp_timer_ctl(c, conn);
}
-#define conn_event(c, conn, event) \
- do { \
- flow_trace(conn, "event at %s:%i", __func__, __LINE__); \
- conn_event_do(c, conn, event); \
- } while (0)
-
/**
* tcp_rtt_dst_low() - Check if low RTT was seen for connection endpoint
* @conn: Connection pointer
@@ -906,104 +756,6 @@ static void tcp_update_check_tcp6(struct ipv6hdr *ip6h, struct tcphdr *th)
th->check = csum(th, l4len, sum);
}
-/**
- * tcp_update_l2_buf() - Update Ethernet header buffers with addresses
- * @eth_d: Ethernet destination address, NULL if unchanged
- * @eth_s: Ethernet source address, NULL if unchanged
- */
-void tcp_update_l2_buf(const unsigned char *eth_d, const unsigned char *eth_s)
-{
- eth_update_mac(&tcp4_eth_src, eth_d, eth_s);
- eth_update_mac(&tcp6_eth_src, eth_d, eth_s);
-}
-
-/**
- * tcp_sock4_iov_init() - Initialise scatter-gather L2 buffers for IPv4 sockets
- * @c: Execution context
- */
-static void tcp_sock4_iov_init(const struct ctx *c)
-{
- struct iphdr iph = L2_BUF_IP4_INIT(IPPROTO_TCP);
- struct iovec *iov;
- int i;
-
- tcp4_eth_src.h_proto = htons_constant(ETH_P_IP);
-
- for (i = 0; i < ARRAY_SIZE(tcp4_payload); i++) {
- tcp4_payload_ip[i] = iph;
- tcp4_payload[i].th.doff = sizeof(struct tcphdr) / 4;
- tcp4_payload[i].th.ack = 1;
- }
-
- for (i = 0; i < ARRAY_SIZE(tcp4_flags); i++) {
- tcp4_flags_ip[i] = iph;
- tcp4_flags[i].th.doff = sizeof(struct tcphdr) / 4;
- tcp4_flags[i].th.ack = 1;
- }
-
- for (i = 0; i < TCP_FRAMES_MEM; i++) {
- iov = tcp4_l2_iov[i];
-
- iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp4_payload_tap_hdr[i]);
- iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp4_eth_src);
- iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp4_payload_ip[i]);
- iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_payload[i];
- }
-
- for (i = 0; i < TCP_FRAMES_MEM; i++) {
- iov = tcp4_l2_flags_iov[i];
-
- iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp4_flags_tap_hdr[i]);
- iov[TCP_IOV_ETH].iov_base = &tcp4_eth_src;
- iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp4_eth_src);
- iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp4_flags_ip[i]);
- iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_flags[i];
- }
-}
-
-/**
- * tcp_sock6_iov_init() - Initialise scatter-gather L2 buffers for IPv6 sockets
- * @c: Execution context
- */
-static void tcp_sock6_iov_init(const struct ctx *c)
-{
- struct ipv6hdr ip6 = L2_BUF_IP6_INIT(IPPROTO_TCP);
- struct iovec *iov;
- int i;
-
- tcp6_eth_src.h_proto = htons_constant(ETH_P_IPV6);
-
- for (i = 0; i < ARRAY_SIZE(tcp6_payload); i++) {
- tcp6_payload_ip[i] = ip6;
- tcp6_payload[i].th.doff = sizeof(struct tcphdr) / 4;
- tcp6_payload[i].th.ack = 1;
- }
-
- for (i = 0; i < ARRAY_SIZE(tcp6_flags); i++) {
- tcp6_flags_ip[i] = ip6;
- tcp6_flags[i].th.doff = sizeof(struct tcphdr) / 4;
- tcp6_flags[i].th .ack = 1;
- }
-
- for (i = 0; i < TCP_FRAMES_MEM; i++) {
- iov = tcp6_l2_iov[i];
-
- iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp6_payload_tap_hdr[i]);
- iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp6_eth_src);
- iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp6_payload_ip[i]);
- iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_payload[i];
- }
-
- for (i = 0; i < TCP_FRAMES_MEM; i++) {
- iov = tcp6_l2_flags_iov[i];
-
- iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp6_flags_tap_hdr[i]);
- iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp6_eth_src);
- iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp6_flags_ip[i]);
- iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_flags[i];
- }
-}
-
/**
* tcp_opt_get() - Get option, and value if any, from TCP header
* @opts: Pointer to start of TCP options in header
@@ -1227,76 +979,6 @@ bool tcp_flow_defer(const struct tcp_tap_conn *conn)
return true;
}
-static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn);
-#define tcp_rst(c, conn) \
- do { \
- flow_dbg((conn), "TCP reset at %s:%i", __func__, __LINE__); \
- tcp_rst_do(c, conn); \
- } while (0)
-
-/**
- * tcp_flags_flush() - Send out buffers for segments with no data (flags)
- * @c: Execution context
- */
-static void tcp_flags_flush(const struct ctx *c)
-{
- tap_send_frames(c, &tcp6_l2_flags_iov[0][0], TCP_NUM_IOVS,
- tcp6_flags_used);
- tcp6_flags_used = 0;
-
- tap_send_frames(c, &tcp4_l2_flags_iov[0][0], TCP_NUM_IOVS,
- tcp4_flags_used);
- tcp4_flags_used = 0;
-}
-
-/**
- * tcp_revert_seq() - Revert affected conn->seq_to_tap after failed transmission
- * @conns: Array of connection pointers corresponding to queued frames
- * @frames: Two-dimensional array containing queued frames with sub-iovs
- * @num_frames: Number of entries in the two arrays to be compared
- */
-static void tcp_revert_seq(struct tcp_tap_conn **conns, struct iovec (*frames)[TCP_NUM_IOVS],
- int num_frames)
-{
- int i;
-
- for (i = 0; i < num_frames; i++) {
- const struct tcphdr *th = frames[i][TCP_IOV_PAYLOAD].iov_base;
- struct tcp_tap_conn *conn = conns[i];
- uint32_t seq = ntohl(th->seq);
-
- if (SEQ_LE(conn->seq_to_tap, seq))
- continue;
-
- conn->seq_to_tap = seq;
- }
-}
-
-/**
- * tcp_payload_flush() - Send out buffers for segments with data
- * @c: Execution context
- */
-static void tcp_payload_flush(const struct ctx *c)
-{
- size_t m;
-
- m = tap_send_frames(c, &tcp6_l2_iov[0][0], TCP_NUM_IOVS,
- tcp6_payload_used);
- if (m != tcp6_payload_used) {
- tcp_revert_seq(&tcp6_frame_conns[m], &tcp6_l2_iov[m],
- tcp6_payload_used - m);
- }
- tcp6_payload_used = 0;
-
- m = tap_send_frames(c, &tcp4_l2_iov[0][0], TCP_NUM_IOVS,
- tcp4_payload_used);
- if (m != tcp4_payload_used) {
- tcp_revert_seq(&tcp4_frame_conns[m], &tcp4_l2_iov[m],
- tcp4_payload_used - m);
- }
- tcp4_payload_used = 0;
-}
-
/**
* tcp_defer_handler() - Handler for TCP deferred tasks
* @c: Execution context
@@ -1430,10 +1112,10 @@ static size_t tcp_fill_headers6(const struct ctx *c,
*
* Return: IP payload length, host order
*/
-static size_t tcp_l2_buf_fill_headers(const struct ctx *c,
- const struct tcp_tap_conn *conn,
- struct iovec *iov, size_t dlen,
- const uint16_t *check, uint32_t seq)
+size_t tcp_l2_buf_fill_headers(const struct ctx *c,
+ const struct tcp_tap_conn *conn,
+ struct iovec *iov, size_t dlen,
+ const uint16_t *check, uint32_t seq)
{
const struct in_addr *a4 = inany_v4(&conn->faddr);
@@ -1459,8 +1141,8 @@ static size_t tcp_l2_buf_fill_headers(const struct ctx *c,
*
* Return: 1 if sequence or window were updated, 0 otherwise
*/
-static int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn,
- int force_seq, struct tcp_info *tinfo)
+int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn,
+ int force_seq, struct tcp_info *tinfo)
{
uint32_t prev_wnd_to_tap = conn->wnd_to_tap << conn->ws_to_tap;
uint32_t prev_ack_to_tap = conn->seq_ack_to_tap;
@@ -1579,9 +1261,9 @@ static void tcp_update_seqack_from_tap(const struct ctx *c,
* 0 if there is no flag to send
* 1 otherwise
*/
-static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
- int flags, struct tcphdr *th, char *data,
- size_t *optlen)
+int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
+ int flags, struct tcphdr *th, char *data,
+ size_t *optlen)
{
struct tcp_info tinfo = { 0 };
socklen_t sl = sizeof(tinfo);
@@ -1678,54 +1360,9 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
*
* Return: negative error code on connection reset, 0 otherwise
*/
-static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
+int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
{
- struct tcp_flags_t *payload;
- struct iovec *iov;
- size_t optlen;
- size_t l4len;
- int ret;
-
- if (CONN_V4(conn))
- iov = tcp4_l2_flags_iov[tcp4_flags_used++];
- else
- iov = tcp6_l2_flags_iov[tcp6_flags_used++];
-
- payload = iov[TCP_IOV_PAYLOAD].iov_base;
-
- ret = tcp_prepare_flags(c, conn, flags, &payload->th,
- payload->opts, &optlen);
- if (ret <= 0)
- return ret;
-
- l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
- conn->seq_to_tap);
- iov[TCP_IOV_PAYLOAD].iov_len = l4len;
-
- if (flags & DUP_ACK) {
- struct iovec *dup_iov;
- int i;
-
- if (CONN_V4(conn))
- dup_iov = tcp4_l2_flags_iov[tcp4_flags_used++];
- else
- dup_iov = tcp6_l2_flags_iov[tcp6_flags_used++];
-
- for (i = 0; i < TCP_NUM_IOVS; i++)
- memcpy(dup_iov[i].iov_base, iov[i].iov_base,
- iov[i].iov_len);
- dup_iov[TCP_IOV_PAYLOAD].iov_len = iov[TCP_IOV_PAYLOAD].iov_len;
- }
-
- if (CONN_V4(conn)) {
- if (tcp4_flags_used > TCP_FRAMES_MEM - 2)
- tcp_flags_flush(c);
- } else {
- if (tcp6_flags_used > TCP_FRAMES_MEM - 2)
- tcp_flags_flush(c);
- }
-
- return 0;
+ return tcp_buf_send_flag(c, conn, flags);
}
/**
@@ -1733,7 +1370,7 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
* @c: Execution context
* @conn: Connection pointer
*/
-static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn)
+void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn)
{
if (conn->events == CLOSED)
return;
@@ -2160,49 +1797,6 @@ static int tcp_sock_consume(const struct tcp_tap_conn *conn, uint32_t ack_seq)
return 0;
}
-/**
- * tcp_data_to_tap() - Finalise (queue) highest-numbered scatter-gather buffer
- * @c: Execution context
- * @conn: Connection pointer
- * @dlen: TCP payload length
- * @no_csum: Don't compute IPv4 checksum, use the one from previous buffer
- * @seq: Sequence number to be sent
- */
-static void tcp_data_to_tap(const struct ctx *c, struct tcp_tap_conn *conn,
- ssize_t dlen, int no_csum, uint32_t seq)
-{
- struct iovec *iov;
- size_t l4len;
-
- conn->seq_to_tap = seq + dlen;
-
- if (CONN_V4(conn)) {
- struct iovec *iov_prev = tcp4_l2_iov[tcp4_payload_used - 1];
- const uint16_t *check = NULL;
-
- if (no_csum) {
- struct iphdr *iph = iov_prev[TCP_IOV_IP].iov_base;
- check = &iph->check;
- }
-
- tcp4_frame_conns[tcp4_payload_used] = conn;
-
- iov = tcp4_l2_iov[tcp4_payload_used++];
- l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, check, seq);
- iov[TCP_IOV_PAYLOAD].iov_len = l4len;
- if (tcp4_payload_used > TCP_FRAMES_MEM - 1)
- tcp_payload_flush(c);
- } else if (CONN_V6(conn)) {
- tcp6_frame_conns[tcp6_payload_used] = conn;
-
- iov = tcp6_l2_iov[tcp6_payload_used++];
- l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, NULL, seq);
- iov[TCP_IOV_PAYLOAD].iov_len = l4len;
- if (tcp6_payload_used > TCP_FRAMES_MEM - 1)
- tcp_payload_flush(c);
- }
-}
-
/**
* tcp_data_from_sock() - Handle new data from socket, queue to tap, in window
* @c: Execution context
@@ -2214,123 +1808,7 @@ static void tcp_data_to_tap(const struct ctx *c, struct tcp_tap_conn *conn,
*/
static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn)
{
- uint32_t wnd_scaled = conn->wnd_from_tap << conn->ws_from_tap;
- int fill_bufs, send_bufs = 0, last_len, iov_rem = 0;
- int sendlen, len, dlen, v4 = CONN_V4(conn);
- int s = conn->sock, i, ret = 0;
- struct msghdr mh_sock = { 0 };
- uint16_t mss = MSS_GET(conn);
- uint32_t already_sent, seq;
- struct iovec *iov;
-
- already_sent = conn->seq_to_tap - conn->seq_ack_from_tap;
-
- if (SEQ_LT(already_sent, 0)) {
- /* RFC 761, section 2.1. */
- flow_trace(conn, "ACK sequence gap: ACK for %u, sent: %u",
- conn->seq_ack_from_tap, conn->seq_to_tap);
- conn->seq_to_tap = conn->seq_ack_from_tap;
- already_sent = 0;
- }
-
- if (!wnd_scaled || already_sent >= wnd_scaled) {
- conn_flag(c, conn, STALLED);
- conn_flag(c, conn, ACK_FROM_TAP_DUE);
- return 0;
- }
-
- /* Set up buffer descriptors we'll fill completely and partially. */
- fill_bufs = DIV_ROUND_UP(wnd_scaled - already_sent, mss);
- if (fill_bufs > TCP_FRAMES) {
- fill_bufs = TCP_FRAMES;
- iov_rem = 0;
- } else {
- iov_rem = (wnd_scaled - already_sent) % mss;
- }
-
- mh_sock.msg_iov = iov_sock;
- mh_sock.msg_iovlen = fill_bufs + 1;
-
- iov_sock[0].iov_base = tcp_buf_discard;
- iov_sock[0].iov_len = already_sent;
-
- if (( v4 && tcp4_payload_used + fill_bufs > TCP_FRAMES_MEM) ||
- (!v4 && tcp6_payload_used + fill_bufs > TCP_FRAMES_MEM)) {
- tcp_payload_flush(c);
-
- /* Silence Coverity CWE-125 false positive */
- tcp4_payload_used = tcp6_payload_used = 0;
- }
-
- for (i = 0, iov = iov_sock + 1; i < fill_bufs; i++, iov++) {
- if (v4)
- iov->iov_base = &tcp4_payload[tcp4_payload_used + i].data;
- else
- iov->iov_base = &tcp6_payload[tcp6_payload_used + i].data;
- iov->iov_len = mss;
- }
- if (iov_rem)
- iov_sock[fill_bufs].iov_len = iov_rem;
-
- /* Receive into buffers, don't dequeue until acknowledged by guest. */
- do
- len = recvmsg(s, &mh_sock, MSG_PEEK);
- while (len < 0 && errno == EINTR);
-
- if (len < 0)
- goto err;
-
- if (!len) {
- if ((conn->events & (SOCK_FIN_RCVD | TAP_FIN_SENT)) == SOCK_FIN_RCVD) {
- if ((ret = tcp_send_flag(c, conn, FIN | ACK))) {
- tcp_rst(c, conn);
- return ret;
- }
-
- conn_event(c, conn, TAP_FIN_SENT);
- }
-
- return 0;
- }
-
- sendlen = len - already_sent;
- if (sendlen <= 0) {
- conn_flag(c, conn, STALLED);
- return 0;
- }
-
- conn_flag(c, conn, ~STALLED);
-
- send_bufs = DIV_ROUND_UP(sendlen, mss);
- last_len = sendlen - (send_bufs - 1) * mss;
-
- /* Likely, some new data was acked too. */
- tcp_update_seqack_wnd(c, conn, 0, NULL);
-
- /* Finally, queue to tap */
- dlen = mss;
- seq = conn->seq_to_tap;
- for (i = 0; i < send_bufs; i++) {
- int no_csum = i && i != send_bufs - 1 && tcp4_payload_used;
-
- if (i == send_bufs - 1)
- dlen = last_len;
-
- tcp_data_to_tap(c, conn, dlen, no_csum, seq);
- seq += dlen;
- }
-
- conn_flag(c, conn, ACK_FROM_TAP_DUE);
-
- return 0;
-
-err:
- if (errno != EAGAIN && errno != EWOULDBLOCK) {
- ret = -errno;
- tcp_rst(c, conn);
- }
-
- return ret;
+ return tcp_buf_data_from_sock(c, conn);
}
/**
diff --git a/tcp_buf.c b/tcp_buf.c
new file mode 100644
index 000000000000..0c7d07b8d0bd
--- /dev/null
+++ b/tcp_buf.c
@@ -0,0 +1,513 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/* PASST - Plug A Simple Socket Transport
+ * for qemu/UNIX domain socket mode
+ *
+ * PASTA - Pack A Subtle Tap Abstraction
+ * for network namespace/tap device mode
+ *
+ * tcp_buf.c - TCP L2-L4 buffer management functions
+ *
+ * Copyright Red Hat
+ * Author: Stefano Brivio <sbrivio@redhat.com>
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+#include <limits.h>
+#include <string.h>
+#include <errno.h>
+
+#include <netinet/ip.h>
+
+#include <linux/tcp.h>
+
+#include "util.h"
+#include "ip.h"
+#include "iov.h"
+#include "passt.h"
+#include "tap.h"
+#include "siphash.h"
+#include "inany.h"
+#include "tcp_conn.h"
+#include "tcp_internal.h"
+#include "tcp_buf.h"
+
+#define TCP_FRAMES_MEM 128
+#define TCP_FRAMES \
+ (c->mode == MODE_PASST ? TCP_FRAMES_MEM : 1)
+
+/* Static buffers */
+/**
+ * struct tcp_payload_t - TCP header and data to send segments with payload
+ * @th: TCP header
+ * @data: TCP data
+ */
+struct tcp_payload_t {
+ struct tcphdr th;
+ uint8_t data[IP_MAX_MTU - sizeof(struct tcphdr)];
+#ifdef __AVX2__
+} __attribute__ ((packed, aligned(32))); /* For AVX2 checksum routines */
+#else
+} __attribute__ ((packed, aligned(__alignof__(unsigned int))));
+#endif
+
+/**
+ * struct tcp_flags_t - TCP header and data to send zero-length
+ * segments (flags)
+ * @th: TCP header
+ * @opts TCP options
+ */
+struct tcp_flags_t {
+ struct tcphdr th;
+ char opts[OPT_MSS_LEN + OPT_WS_LEN + 1];
+#ifdef __AVX2__
+} __attribute__ ((packed, aligned(32)));
+#else
+} __attribute__ ((packed, aligned(__alignof__(unsigned int))));
+#endif
+
+/* Ethernet header for IPv4 frames */
+static struct ethhdr tcp4_eth_src;
+
+static struct tap_hdr tcp4_payload_tap_hdr[TCP_FRAMES_MEM];
+/* IPv4 headers */
+static struct iphdr tcp4_payload_ip[TCP_FRAMES_MEM];
+/* TCP segments with payload for IPv4 frames */
+static struct tcp_payload_t tcp4_payload[TCP_FRAMES_MEM];
+
+static_assert(MSS4 <= sizeof(tcp4_payload[0].data), "MSS4 is greater than 65516");
+
+/* References tracking the owner connection of frames in the tap outqueue */
+static struct tcp_tap_conn *tcp4_frame_conns[TCP_FRAMES_MEM];
+static unsigned int tcp4_payload_used;
+
+static struct tap_hdr tcp4_flags_tap_hdr[TCP_FRAMES_MEM];
+/* IPv4 headers for TCP segment without payload */
+static struct iphdr tcp4_flags_ip[TCP_FRAMES_MEM];
+/* TCP segments without payload for IPv4 frames */
+static struct tcp_flags_t tcp4_flags[TCP_FRAMES_MEM];
+
+static unsigned int tcp4_flags_used;
+
+/* Ethernet header for IPv6 frames */
+static struct ethhdr tcp6_eth_src;
+
+static struct tap_hdr tcp6_payload_tap_hdr[TCP_FRAMES_MEM];
+/* IPv6 headers */
+static struct ipv6hdr tcp6_payload_ip[TCP_FRAMES_MEM];
+/* TCP headers and data for IPv6 frames */
+static struct tcp_payload_t tcp6_payload[TCP_FRAMES_MEM];
+
+static_assert(MSS6 <= sizeof(tcp6_payload[0].data), "MSS6 is greater than 65516");
+
+/* References tracking the owner connection of frames in the tap outqueue */
+static struct tcp_tap_conn *tcp6_frame_conns[TCP_FRAMES_MEM];
+static unsigned int tcp6_payload_used;
+
+static struct tap_hdr tcp6_flags_tap_hdr[TCP_FRAMES_MEM];
+/* IPv6 headers for TCP segment without payload */
+static struct ipv6hdr tcp6_flags_ip[TCP_FRAMES_MEM];
+/* TCP segment without payload for IPv6 frames */
+static struct tcp_flags_t tcp6_flags[TCP_FRAMES_MEM];
+
+static unsigned int tcp6_flags_used;
+
+/* recvmsg()/sendmsg() data for tap */
+static struct iovec iov_sock [TCP_FRAMES_MEM + 1];
+
+static struct iovec tcp4_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
+static struct iovec tcp6_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
+static struct iovec tcp4_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
+static struct iovec tcp6_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
+/**
+ * tcp_update_l2_buf() - Update Ethernet header buffers with addresses
+ * @eth_d: Ethernet destination address, NULL if unchanged
+ * @eth_s: Ethernet source address, NULL if unchanged
+ */
+void tcp_update_l2_buf(const unsigned char *eth_d, const unsigned char *eth_s)
+{
+ eth_update_mac(&tcp4_eth_src, eth_d, eth_s);
+ eth_update_mac(&tcp6_eth_src, eth_d, eth_s);
+}
+
+/**
+ * tcp_sock4_iov_init() - Initialise scatter-gather L2 buffers for IPv4 sockets
+ * @c: Execution context
+ */
+void tcp_sock4_iov_init(const struct ctx *c)
+{
+ struct iphdr iph = L2_BUF_IP4_INIT(IPPROTO_TCP);
+ struct iovec *iov;
+ int i;
+
+ tcp4_eth_src.h_proto = htons_constant(ETH_P_IP);
+
+ for (i = 0; i < ARRAY_SIZE(tcp4_payload); i++) {
+ tcp4_payload_ip[i] = iph;
+ tcp4_payload[i].th.doff = sizeof(struct tcphdr) / 4;
+ tcp4_payload[i].th.ack = 1;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(tcp4_flags); i++) {
+ tcp4_flags_ip[i] = iph;
+ tcp4_flags[i].th.doff = sizeof(struct tcphdr) / 4;
+ tcp4_flags[i].th.ack = 1;
+ }
+
+ for (i = 0; i < TCP_FRAMES_MEM; i++) {
+ iov = tcp4_l2_iov[i];
+
+ iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp4_payload_tap_hdr[i]);
+ iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp4_eth_src);
+ iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp4_payload_ip[i]);
+ iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_payload[i];
+ }
+
+ for (i = 0; i < TCP_FRAMES_MEM; i++) {
+ iov = tcp4_l2_flags_iov[i];
+
+ iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp4_flags_tap_hdr[i]);
+ iov[TCP_IOV_ETH].iov_base = &tcp4_eth_src;
+ iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp4_eth_src);
+ iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp4_flags_ip[i]);
+ iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_flags[i];
+ }
+}
+
+/**
+ * tcp_sock6_iov_init() - Initialise scatter-gather L2 buffers for IPv6 sockets
+ * @c: Execution context
+ */
+void tcp_sock6_iov_init(const struct ctx *c)
+{
+ struct ipv6hdr ip6 = L2_BUF_IP6_INIT(IPPROTO_TCP);
+ struct iovec *iov;
+ int i;
+
+ tcp6_eth_src.h_proto = htons_constant(ETH_P_IPV6);
+
+ for (i = 0; i < ARRAY_SIZE(tcp6_payload); i++) {
+ tcp6_payload_ip[i] = ip6;
+ tcp6_payload[i].th.doff = sizeof(struct tcphdr) / 4;
+ tcp6_payload[i].th.ack = 1;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(tcp6_flags); i++) {
+ tcp6_flags_ip[i] = ip6;
+ tcp6_flags[i].th.doff = sizeof(struct tcphdr) / 4;
+ tcp6_flags[i].th .ack = 1;
+ }
+
+ for (i = 0; i < TCP_FRAMES_MEM; i++) {
+ iov = tcp6_l2_iov[i];
+
+ iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp6_payload_tap_hdr[i]);
+ iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp6_eth_src);
+ iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp6_payload_ip[i]);
+ iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_payload[i];
+ }
+
+ for (i = 0; i < TCP_FRAMES_MEM; i++) {
+ iov = tcp6_l2_flags_iov[i];
+
+ iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp6_flags_tap_hdr[i]);
+ iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp6_eth_src);
+ iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp6_flags_ip[i]);
+ iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_flags[i];
+ }
+}
+
+/**
+ * tcp_flags_flush() - Send out buffers for segments with no data (flags)
+ * @c: Execution context
+ */
+void tcp_flags_flush(const struct ctx *c)
+{
+ tap_send_frames(c, &tcp6_l2_flags_iov[0][0], TCP_NUM_IOVS,
+ tcp6_flags_used);
+ tcp6_flags_used = 0;
+
+ tap_send_frames(c, &tcp4_l2_flags_iov[0][0], TCP_NUM_IOVS,
+ tcp4_flags_used);
+ tcp4_flags_used = 0;
+}
+
+/**
+ * tcp_revert_seq() - Revert affected conn->seq_to_tap after failed transmission
+ * @conns: Array of connection pointers corresponding to queued frames
+ * @frames: Two-dimensional array containing queued frames with sub-iovs
+ * @num_frames: Number of entries in the two arrays to be compared
+ */
+static void tcp_revert_seq(struct tcp_tap_conn **conns, struct iovec (*frames)[TCP_NUM_IOVS],
+ int num_frames)
+{
+ int i;
+
+ for (i = 0; i < num_frames; i++) {
+ const struct tcphdr *th = frames[i][TCP_IOV_PAYLOAD].iov_base;
+ struct tcp_tap_conn *conn = conns[i];
+ uint32_t seq = ntohl(th->seq);
+
+ if (SEQ_LE(conn->seq_to_tap, seq))
+ continue;
+
+ conn->seq_to_tap = seq;
+ }
+}
+
+/**
+ * tcp_payload_flush() - Send out buffers for segments with data
+ * @c: Execution context
+ */
+void tcp_payload_flush(const struct ctx *c)
+{
+ size_t m;
+
+ m = tap_send_frames(c, &tcp6_l2_iov[0][0], TCP_NUM_IOVS,
+ tcp6_payload_used);
+ if (m != tcp6_payload_used) {
+ tcp_revert_seq(&tcp6_frame_conns[m], &tcp6_l2_iov[m],
+ tcp6_payload_used - m);
+ }
+ tcp6_payload_used = 0;
+
+ m = tap_send_frames(c, &tcp4_l2_iov[0][0], TCP_NUM_IOVS,
+ tcp4_payload_used);
+ if (m != tcp4_payload_used) {
+ tcp_revert_seq(&tcp4_frame_conns[m], &tcp4_l2_iov[m],
+ tcp4_payload_used - m);
+ }
+ tcp4_payload_used = 0;
+}
+
+/**
+ * tcp_buf_send_flag() - Send segment with flags to tap (no payload)
+ * @c: Execution context
+ * @conn: Connection pointer
+ * @flags: TCP flags: if not set, send segment only if ACK is due
+ *
+ * Return: negative error code on connection reset, 0 otherwise
+ */
+int tcp_buf_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
+{
+ struct tcp_flags_t *payload;
+ struct iovec *iov;
+ size_t optlen;
+ size_t l4len;
+ int ret;
+
+ if (CONN_V4(conn))
+ iov = tcp4_l2_flags_iov[tcp4_flags_used++];
+ else
+ iov = tcp6_l2_flags_iov[tcp6_flags_used++];
+
+ payload = iov[TCP_IOV_PAYLOAD].iov_base;
+
+ ret = tcp_prepare_flags(c, conn, flags, &payload->th,
+ payload->opts, &optlen);
+ if (ret <= 0)
+ return ret;
+
+ l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
+ conn->seq_to_tap);
+ iov[TCP_IOV_PAYLOAD].iov_len = l4len;
+
+ if (flags & DUP_ACK) {
+ struct iovec *dup_iov;
+ int i;
+
+ if (CONN_V4(conn))
+ dup_iov = tcp4_l2_flags_iov[tcp4_flags_used++];
+ else
+ dup_iov = tcp6_l2_flags_iov[tcp6_flags_used++];
+
+ for (i = 0; i < TCP_NUM_IOVS; i++)
+ memcpy(dup_iov[i].iov_base, iov[i].iov_base,
+ iov[i].iov_len);
+ dup_iov[TCP_IOV_PAYLOAD].iov_len = iov[TCP_IOV_PAYLOAD].iov_len;
+ }
+
+ if (CONN_V4(conn)) {
+ if (tcp4_flags_used > TCP_FRAMES_MEM - 2)
+ tcp_flags_flush(c);
+ } else {
+ if (tcp6_flags_used > TCP_FRAMES_MEM - 2)
+ tcp_flags_flush(c);
+ }
+
+ return 0;
+}
+
+/**
+ * tcp_data_to_tap() - Finalise (queue) highest-numbered scatter-gather buffer
+ * @c: Execution context
+ * @conn: Connection pointer
+ * @dlen: TCP payload length
+ * @no_csum: Don't compute IPv4 checksum, use the one from previous buffer
+ * @seq: Sequence number to be sent
+ */
+static void tcp_data_to_tap(const struct ctx *c, struct tcp_tap_conn *conn,
+ ssize_t dlen, int no_csum, uint32_t seq)
+{
+ struct iovec *iov;
+ size_t l4len;
+
+ conn->seq_to_tap = seq + dlen;
+
+ if (CONN_V4(conn)) {
+ struct iovec *iov_prev = tcp4_l2_iov[tcp4_payload_used - 1];
+ const uint16_t *check = NULL;
+
+ if (no_csum) {
+ struct iphdr *iph = iov_prev[TCP_IOV_IP].iov_base;
+ check = &iph->check;
+ }
+
+ tcp4_frame_conns[tcp4_payload_used] = conn;
+
+ iov = tcp4_l2_iov[tcp4_payload_used++];
+ l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, check, seq);
+ iov[TCP_IOV_PAYLOAD].iov_len = l4len;
+ if (tcp4_payload_used > TCP_FRAMES_MEM - 1)
+ tcp_payload_flush(c);
+ } else if (CONN_V6(conn)) {
+ tcp6_frame_conns[tcp6_payload_used] = conn;
+
+ iov = tcp6_l2_iov[tcp6_payload_used++];
+ l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, NULL, seq);
+ iov[TCP_IOV_PAYLOAD].iov_len = l4len;
+ if (tcp6_payload_used > TCP_FRAMES_MEM - 1)
+ tcp_payload_flush(c);
+ }
+}
+
+/**
+ * tcp_buf_data_from_sock() - Handle new data from socket, queue to tap, in window
+ * @c: Execution context
+ * @conn: Connection pointer
+ *
+ * Return: negative on connection reset, 0 otherwise
+ *
+ * #syscalls recvmsg
+ */
+int tcp_buf_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn)
+{
+ uint32_t wnd_scaled = conn->wnd_from_tap << conn->ws_from_tap;
+ int fill_bufs, send_bufs = 0, last_len, iov_rem = 0;
+ int sendlen, len, dlen, v4 = CONN_V4(conn);
+ int s = conn->sock, i, ret = 0;
+ struct msghdr mh_sock = { 0 };
+ uint16_t mss = MSS_GET(conn);
+ uint32_t already_sent, seq;
+ struct iovec *iov;
+
+ already_sent = conn->seq_to_tap - conn->seq_ack_from_tap;
+
+ if (SEQ_LT(already_sent, 0)) {
+ /* RFC 761, section 2.1. */
+ flow_trace(conn, "ACK sequence gap: ACK for %u, sent: %u",
+ conn->seq_ack_from_tap, conn->seq_to_tap);
+ conn->seq_to_tap = conn->seq_ack_from_tap;
+ already_sent = 0;
+ }
+
+ if (!wnd_scaled || already_sent >= wnd_scaled) {
+ conn_flag(c, conn, STALLED);
+ conn_flag(c, conn, ACK_FROM_TAP_DUE);
+ return 0;
+ }
+
+ /* Set up buffer descriptors we'll fill completely and partially. */
+ fill_bufs = DIV_ROUND_UP(wnd_scaled - already_sent, mss);
+ if (fill_bufs > TCP_FRAMES) {
+ fill_bufs = TCP_FRAMES;
+ iov_rem = 0;
+ } else {
+ iov_rem = (wnd_scaled - already_sent) % mss;
+ }
+
+ mh_sock.msg_iov = iov_sock;
+ mh_sock.msg_iovlen = fill_bufs + 1;
+
+ iov_sock[0].iov_base = tcp_buf_discard;
+ iov_sock[0].iov_len = already_sent;
+
+ if (( v4 && tcp4_payload_used + fill_bufs > TCP_FRAMES_MEM) ||
+ (!v4 && tcp6_payload_used + fill_bufs > TCP_FRAMES_MEM)) {
+ tcp_payload_flush(c);
+
+ /* Silence Coverity CWE-125 false positive */
+ tcp4_payload_used = tcp6_payload_used = 0;
+ }
+
+ for (i = 0, iov = iov_sock + 1; i < fill_bufs; i++, iov++) {
+ if (v4)
+ iov->iov_base = &tcp4_payload[tcp4_payload_used + i].data;
+ else
+ iov->iov_base = &tcp6_payload[tcp6_payload_used + i].data;
+ iov->iov_len = mss;
+ }
+ if (iov_rem)
+ iov_sock[fill_bufs].iov_len = iov_rem;
+
+ /* Receive into buffers, don't dequeue until acknowledged by guest. */
+ do
+ len = recvmsg(s, &mh_sock, MSG_PEEK);
+ while (len < 0 && errno == EINTR);
+
+ if (len < 0)
+ goto err;
+
+ if (!len) {
+ if ((conn->events & (SOCK_FIN_RCVD | TAP_FIN_SENT)) == SOCK_FIN_RCVD) {
+ if ((ret = tcp_buf_send_flag(c, conn, FIN | ACK))) {
+ tcp_rst(c, conn);
+ return ret;
+ }
+
+ conn_event(c, conn, TAP_FIN_SENT);
+ }
+
+ return 0;
+ }
+
+ sendlen = len - already_sent;
+ if (sendlen <= 0) {
+ conn_flag(c, conn, STALLED);
+ return 0;
+ }
+
+ conn_flag(c, conn, ~STALLED);
+
+ send_bufs = DIV_ROUND_UP(sendlen, mss);
+ last_len = sendlen - (send_bufs - 1) * mss;
+
+ /* Likely, some new data was acked too. */
+ tcp_update_seqack_wnd(c, conn, 0, NULL);
+
+ /* Finally, queue to tap */
+ dlen = mss;
+ seq = conn->seq_to_tap;
+ for (i = 0; i < send_bufs; i++) {
+ int no_csum = i && i != send_bufs - 1 && tcp4_payload_used;
+
+ if (i == send_bufs - 1)
+ dlen = last_len;
+
+ tcp_data_to_tap(c, conn, dlen, no_csum, seq);
+ seq += dlen;
+ }
+
+ conn_flag(c, conn, ACK_FROM_TAP_DUE);
+
+ return 0;
+
+err:
+ if (errno != EAGAIN && errno != EWOULDBLOCK) {
+ ret = -errno;
+ tcp_rst(c, conn);
+ }
+
+ return ret;
+}
diff --git a/tcp_buf.h b/tcp_buf.h
new file mode 100644
index 000000000000..14be7b945285
--- /dev/null
+++ b/tcp_buf.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright (c) 2021 Red Hat GmbH
+ * Author: Stefano Brivio <sbrivio@redhat.com>
+ */
+
+#ifndef TCP_BUF_H
+#define TCP_BUF_H
+
+void tcp_sock4_iov_init(const struct ctx *c);
+void tcp_sock6_iov_init(const struct ctx *c);
+void tcp_flags_flush(const struct ctx *c);
+void tcp_payload_flush(const struct ctx *c);
+int tcp_buf_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn);
+int tcp_buf_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags);
+
+#endif /*TCP_BUF_H */
diff --git a/tcp_internal.h b/tcp_internal.h
new file mode 100644
index 000000000000..51aaa16918cf
--- /dev/null
+++ b/tcp_internal.h
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright (c) 2021 Red Hat GmbH
+ * Author: Stefano Brivio <sbrivio@redhat.com>
+ */
+
+#ifndef TCP_INTERNAL_H
+#define TCP_INTERNAL_H
+
+#define MAX_WS 8
+#define MAX_WINDOW (1 << (16 + (MAX_WS)))
+
+#define MSS4 ROUND_DOWN(IP_MAX_MTU - \
+ sizeof(struct tcphdr) - \
+ sizeof(struct iphdr), \
+ sizeof(uint32_t))
+#define MSS6 ROUND_DOWN(IP_MAX_MTU - \
+ sizeof(struct tcphdr) - \
+ sizeof(struct ipv6hdr), \
+ sizeof(uint32_t))
+
+#define SEQ_LE(a, b) ((b) - (a) < MAX_WINDOW)
+#define SEQ_LT(a, b) ((b) - (a) - 1 < MAX_WINDOW)
+#define SEQ_GE(a, b) ((a) - (b) < MAX_WINDOW)
+#define SEQ_GT(a, b) ((a) - (b) - 1 < MAX_WINDOW)
+
+#define FIN (1 << 0)
+#define SYN (1 << 1)
+#define RST (1 << 2)
+#define ACK (1 << 4)
+
+/* Flags for internal usage */
+#define DUP_ACK (1 << 5)
+#define OPT_EOL 0
+#define OPT_NOP 1
+#define OPT_MSS 2
+#define OPT_MSS_LEN 4
+#define OPT_WS 3
+#define OPT_WS_LEN 3
+#define OPT_SACKP 4
+#define OPT_SACK 5
+#define OPT_TS 8
+#define CONN_V4(conn) (!!inany_v4(&(conn)->faddr))
+#define CONN_V6(conn) (!CONN_V4(conn))
+
+/*
+ * enum tcp_iov_parts - I/O vector parts for one TCP frame
+ * @TCP_IOV_TAP tap backend specific header
+ * @TCP_IOV_ETH Ethernet header
+ * @TCP_IOV_IP IP (v4/v6) header
+ * @TCP_IOV_PAYLOAD IP payload (TCP header + data)
+ * @TCP_NUM_IOVS the number of entries in the iovec array
+ */
+enum tcp_iov_parts {
+ TCP_IOV_TAP = 0,
+ TCP_IOV_ETH = 1,
+ TCP_IOV_IP = 2,
+ TCP_IOV_PAYLOAD = 3,
+ TCP_NUM_IOVS
+};
+
+extern char tcp_buf_discard [MAX_WINDOW];
+
+void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
+ unsigned long flag);
+#define conn_flag(c, conn, flag) \
+ do { \
+ flow_trace(conn, "flag at %s:%i", __func__, __LINE__); \
+ conn_flag_do(c, conn, flag); \
+ } while (0)
+
+
+void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
+ unsigned long event);
+#define conn_event(c, conn, event) \
+ do { \
+ flow_trace(conn, "event at %s:%i", __func__, __LINE__); \
+ conn_event_do(c, conn, event); \
+ } while (0)
+
+void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn);
+#define tcp_rst(c, conn) \
+ do { \
+ flow_dbg((conn), "TCP reset at %s:%i", __func__, __LINE__); \
+ tcp_rst_do(c, conn); \
+ } while (0)
+
+size_t tcp_l2_buf_fill_headers(const struct ctx *c,
+ const struct tcp_tap_conn *conn,
+ struct iovec *iov, size_t dlen,
+ const uint16_t *check, uint32_t seq);
+int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn,
+ int force_seq, struct tcp_info *tinfo);
+int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn, int flags,
+ struct tcphdr *th, char *data, size_t *optlen);
+
+#endif /* TCP_INTERNAL_H */
--
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright (c) 2021 Red Hat GmbH
+ * Author: Stefano Brivio <sbrivio@redhat.com>
+ */
+
+#ifndef TCP_INTERNAL_H
+#define TCP_INTERNAL_H
+
+#define MAX_WS 8
+#define MAX_WINDOW (1 << (16 + (MAX_WS)))
+
+#define MSS4 ROUND_DOWN(IP_MAX_MTU - \
+ sizeof(struct tcphdr) - \
+ sizeof(struct iphdr), \
+ sizeof(uint32_t))
+#define MSS6 ROUND_DOWN(IP_MAX_MTU - \
+ sizeof(struct tcphdr) - \
+ sizeof(struct ipv6hdr), \
+ sizeof(uint32_t))
+
+#define SEQ_LE(a, b) ((b) - (a) < MAX_WINDOW)
+#define SEQ_LT(a, b) ((b) - (a) - 1 < MAX_WINDOW)
+#define SEQ_GE(a, b) ((a) - (b) < MAX_WINDOW)
+#define SEQ_GT(a, b) ((a) - (b) - 1 < MAX_WINDOW)
+
+#define FIN (1 << 0)
+#define SYN (1 << 1)
+#define RST (1 << 2)
+#define ACK (1 << 4)
+
+/* Flags for internal usage */
+#define DUP_ACK (1 << 5)
+#define OPT_EOL 0
+#define OPT_NOP 1
+#define OPT_MSS 2
+#define OPT_MSS_LEN 4
+#define OPT_WS 3
+#define OPT_WS_LEN 3
+#define OPT_SACKP 4
+#define OPT_SACK 5
+#define OPT_TS 8
+#define CONN_V4(conn) (!!inany_v4(&(conn)->faddr))
+#define CONN_V6(conn) (!CONN_V4(conn))
+
+/*
+ * enum tcp_iov_parts - I/O vector parts for one TCP frame
+ * @TCP_IOV_TAP tap backend specific header
+ * @TCP_IOV_ETH Ethernet header
+ * @TCP_IOV_IP IP (v4/v6) header
+ * @TCP_IOV_PAYLOAD IP payload (TCP header + data)
+ * @TCP_NUM_IOVS the number of entries in the iovec array
+ */
+enum tcp_iov_parts {
+ TCP_IOV_TAP = 0,
+ TCP_IOV_ETH = 1,
+ TCP_IOV_IP = 2,
+ TCP_IOV_PAYLOAD = 3,
+ TCP_NUM_IOVS
+};
+
+extern char tcp_buf_discard [MAX_WINDOW];
+
+void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
+ unsigned long flag);
+#define conn_flag(c, conn, flag) \
+ do { \
+ flow_trace(conn, "flag at %s:%i", __func__, __LINE__); \
+ conn_flag_do(c, conn, flag); \
+ } while (0)
+
+
+void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
+ unsigned long event);
+#define conn_event(c, conn, event) \
+ do { \
+ flow_trace(conn, "event at %s:%i", __func__, __LINE__); \
+ conn_event_do(c, conn, event); \
+ } while (0)
+
+void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn);
+#define tcp_rst(c, conn) \
+ do { \
+ flow_dbg((conn), "TCP reset at %s:%i", __func__, __LINE__); \
+ tcp_rst_do(c, conn); \
+ } while (0)
+
+size_t tcp_l2_buf_fill_headers(const struct ctx *c,
+ const struct tcp_tap_conn *conn,
+ struct iovec *iov, size_t dlen,
+ const uint16_t *check, uint32_t seq);
+int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn,
+ int force_seq, struct tcp_info *tinfo);
+int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn, int flags,
+ struct tcphdr *th, char *data, size_t *optlen);
+
+#endif /* TCP_INTERNAL_H */
--
2.45.2
^ permalink raw reply related [flat|nested] 25+ messages in thread* Re: [PATCH v6 2/8] tcp: move buffers management functions to their own file
2024-06-12 15:47 ` [PATCH v6 2/8] tcp: move buffers management functions to their own file Laurent Vivier
@ 2024-06-12 15:54 ` Stefano Brivio
0 siblings, 0 replies; 25+ messages in thread
From: Stefano Brivio @ 2024-06-12 15:54 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
On Wed, 12 Jun 2024 17:47:28 +0200
Laurent Vivier <lvivier@redhat.com> wrote:
> Move all the TCP parts using internal buffers to tcp_buf.c
> and keep generic TCP management functions in tcp.c.
> Add tcp_internal.h to export needed functions from tcp.c and
> tcp_buf.h from tcp_buf.c
>
> With this change we can use existing TCP functions with a
> different kind of memory storage as for instance the shared
> memory provided by the guest via vhost-user.
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
>
> Notes:
> v5:
> - as we export now tcp_l2_buf_fill_headers() move
> also enum tcp_iov_part to tcp_internal.h
>
> v4:
> - rename tcp_send_flag() and tcp_data_from_sock() to
> tcp_buf_send_flag() and tcp_buf_data_from_sock()
>
> Makefile | 5 +-
> tcp.c | 562 ++-----------------------------------------------
> tcp_buf.c | 513 ++++++++++++++++++++++++++++++++++++++++++++
> tcp_buf.h | 16 ++
> tcp_internal.h | 96 +++++++++
> 5 files changed, 648 insertions(+), 544 deletions(-)
> create mode 100644 tcp_buf.c
> create mode 100644 tcp_buf.h
> create mode 100644 tcp_internal.h
>
> diff --git a/Makefile b/Makefile
> index e2180b599bdb..09fc461d087e 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -47,7 +47,7 @@ FLAGS += -DDUAL_STACK_SOCKETS=$(DUAL_STACK_SOCKETS)
> PASST_SRCS = arch.c arp.c checksum.c conf.c dhcp.c dhcpv6.c flow.c fwd.c \
> icmp.c igmp.c inany.c iov.c ip.c isolation.c lineread.c log.c mld.c \
> ndp.c netlink.c packet.c passt.c pasta.c pcap.c pif.c tap.c tcp.c \
> - tcp_splice.c udp.c util.c
> + tcp_buf.c tcp_splice.c udp.c util.c
> QRAP_SRCS = qrap.c
> SRCS = $(PASST_SRCS) $(QRAP_SRCS)
>
> @@ -56,7 +56,8 @@ MANPAGES = passt.1 pasta.1 qrap.1
> PASST_HEADERS = arch.h arp.h checksum.h conf.h dhcp.h dhcpv6.h flow.h fwd.h \
> flow_table.h icmp.h icmp_flow.h inany.h iov.h ip.h isolation.h \
> lineread.h log.h ndp.h netlink.h packet.h passt.h pasta.h pcap.h pif.h \
> - siphash.h tap.h tcp.h tcp_conn.h tcp_splice.h udp.h util.h
> + siphash.h tap.h tcp.h tcp_buf.h tcp_conn.h tcp_internal.h tcp_splice.h \
> + udp.h util.h
> HEADERS = $(PASST_HEADERS) seccomp.h
>
> C := \#include <linux/tcp.h>\nstruct tcp_info x = { .tcpi_snd_wnd = 0 };
> diff --git a/tcp.c b/tcp.c
> index 6800209d4122..875e318c925b 100644
> --- a/tcp.c
> +++ b/tcp.c
> @@ -302,28 +302,14 @@
> #include "flow.h"
>
> #include "flow_table.h"
> -
> -#define TCP_FRAMES_MEM 128
> -#define TCP_FRAMES \
> - (c->mode == MODE_PASST ? TCP_FRAMES_MEM : 1)
> +#include "tcp_internal.h"
> +#include "tcp_buf.h"
>
> #define TCP_HASH_TABLE_LOAD 70 /* % */
> #define TCP_HASH_TABLE_SIZE (FLOW_MAX * 100 / TCP_HASH_TABLE_LOAD)
>
> -#define MAX_WS 8
> -#define MAX_WINDOW (1 << (16 + (MAX_WS)))
> -
> /* MSS rounding: see SET_MSS() */
> #define MSS_DEFAULT 536
> -#define MSS4 ROUND_DOWN(IP_MAX_MTU - \
> - sizeof(struct tcphdr) - \
> - sizeof(struct iphdr), \
> - sizeof(uint32_t))
> -#define MSS6 ROUND_DOWN(IP_MAX_MTU - \
> - sizeof(struct tcphdr) - \
> - sizeof(struct ipv6hdr), \
> - sizeof(uint32_t))
> -
> #define WINDOW_DEFAULT 14600 /* RFC 6928 */
> #ifdef HAS_SND_WND
> # define KERNEL_REPORTS_SND_WND(c) ((c)->tcp.kernel_snd_wnd)
> @@ -345,33 +331,10 @@
> */
> #define SOL_TCP IPPROTO_TCP
>
> -#define SEQ_LE(a, b) ((b) - (a) < MAX_WINDOW)
> -#define SEQ_LT(a, b) ((b) - (a) - 1 < MAX_WINDOW)
> -#define SEQ_GE(a, b) ((a) - (b) < MAX_WINDOW)
> -#define SEQ_GT(a, b) ((a) - (b) - 1 < MAX_WINDOW)
> -
> -#define FIN (1 << 0)
> -#define SYN (1 << 1)
> -#define RST (1 << 2)
> -#define ACK (1 << 4)
> -/* Flags for internal usage */
> -#define DUP_ACK (1 << 5)
> #define ACK_IF_NEEDED 0 /* See tcp_send_flag() */
>
> -#define OPT_EOL 0
> -#define OPT_NOP 1
> -#define OPT_MSS 2
> -#define OPT_MSS_LEN 4
> -#define OPT_WS 3
> -#define OPT_WS_LEN 3
> -#define OPT_SACKP 4
> -#define OPT_SACK 5
> -#define OPT_TS 8
> -
> #define TAPSIDE(conn_) ((conn_)->f.pif[1] == PIF_TAP)
>
> -#define CONN_V4(conn) (!!inany_v4(&(conn)->faddr))
> -#define CONN_V6(conn) (!CONN_V4(conn))
> #define CONN_IS_CLOSING(conn) \
> (((conn)->events & ESTABLISHED) && \
> ((conn)->events & (SOCK_FIN_RCVD | TAP_FIN_RCVD)))
> @@ -408,106 +371,7 @@ static int tcp_sock_ns [NUM_PORTS][IP_VERSIONS];
> */
> static union inany_addr low_rtt_dst[LOW_RTT_TABLE_SIZE];
>
> -/* Static buffers */
> -/**
> - * struct tcp_payload_t - TCP header and data to send segments with payload
> - * @th: TCP header
> - * @data: TCP data
> - */
> -struct tcp_payload_t {
> - struct tcphdr th;
> - uint8_t data[IP_MAX_MTU - sizeof(struct tcphdr)];
> -#ifdef __AVX2__
> -} __attribute__ ((packed, aligned(32))); /* For AVX2 checksum routines */
> -#else
> -} __attribute__ ((packed, aligned(__alignof__(unsigned int))));
> -#endif
> -
> -/**
> - * struct tcp_flags_t - TCP header and data to send zero-length
> - * segments (flags)
> - * @th: TCP header
> - * @opts TCP options
> - */
> -struct tcp_flags_t {
> - struct tcphdr th;
> - char opts[OPT_MSS_LEN + OPT_WS_LEN + 1];
> -#ifdef __AVX2__
> -} __attribute__ ((packed, aligned(32)));
> -#else
> -} __attribute__ ((packed, aligned(__alignof__(unsigned int))));
> -#endif
> -
> -/* Ethernet header for IPv4 frames */
> -static struct ethhdr tcp4_eth_src;
> -
> -static struct tap_hdr tcp4_payload_tap_hdr[TCP_FRAMES_MEM];
> -/* IPv4 headers */
> -static struct iphdr tcp4_payload_ip[TCP_FRAMES_MEM];
> -/* TCP segments with payload for IPv4 frames */
> -static struct tcp_payload_t tcp4_payload[TCP_FRAMES_MEM];
> -
> -static_assert(MSS4 <= sizeof(tcp4_payload[0].data), "MSS4 is greater than 65516");
> -
> -/* References tracking the owner connection of frames in the tap outqueue */
> -static struct tcp_tap_conn *tcp4_frame_conns[TCP_FRAMES_MEM];
> -static unsigned int tcp4_payload_used;
> -
> -static struct tap_hdr tcp4_flags_tap_hdr[TCP_FRAMES_MEM];
> -/* IPv4 headers for TCP segment without payload */
> -static struct iphdr tcp4_flags_ip[TCP_FRAMES_MEM];
> -/* TCP segments without payload for IPv4 frames */
> -static struct tcp_flags_t tcp4_flags[TCP_FRAMES_MEM];
> -
> -static unsigned int tcp4_flags_used;
> -
> -/* Ethernet header for IPv6 frames */
> -static struct ethhdr tcp6_eth_src;
> -
> -static struct tap_hdr tcp6_payload_tap_hdr[TCP_FRAMES_MEM];
> -/* IPv6 headers */
> -static struct ipv6hdr tcp6_payload_ip[TCP_FRAMES_MEM];
> -/* TCP headers and data for IPv6 frames */
> -static struct tcp_payload_t tcp6_payload[TCP_FRAMES_MEM];
> -
> -static_assert(MSS6 <= sizeof(tcp6_payload[0].data), "MSS6 is greater than 65516");
> -
> -/* References tracking the owner connection of frames in the tap outqueue */
> -static struct tcp_tap_conn *tcp6_frame_conns[TCP_FRAMES_MEM];
> -static unsigned int tcp6_payload_used;
> -
> -static struct tap_hdr tcp6_flags_tap_hdr[TCP_FRAMES_MEM];
> -/* IPv6 headers for TCP segment without payload */
> -static struct ipv6hdr tcp6_flags_ip[TCP_FRAMES_MEM];
> -/* TCP segment without payload for IPv6 frames */
> -static struct tcp_flags_t tcp6_flags[TCP_FRAMES_MEM];
> -
> -static unsigned int tcp6_flags_used;
> -
> -/* recvmsg()/sendmsg() data for tap */
> -static char tcp_buf_discard [MAX_WINDOW];
> -static struct iovec iov_sock [TCP_FRAMES_MEM + 1];
> -
> -/*
> - * enum tcp_iov_parts - I/O vector parts for one TCP frame
> - * @TCP_IOV_TAP tap backend specific header
> - * @TCP_IOV_ETH Ethernet header
> - * @TCP_IOV_IP IP (v4/v6) header
> - * @TCP_IOV_PAYLOAD IP payload (TCP header + data)
> - * @TCP_NUM_IOVS the number of entries in the iovec array
> - */
> -enum tcp_iov_parts {
> - TCP_IOV_TAP = 0,
> - TCP_IOV_ETH = 1,
> - TCP_IOV_IP = 2,
> - TCP_IOV_PAYLOAD = 3,
> - TCP_NUM_IOVS
> -};
> -
> -static struct iovec tcp4_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
> -static struct iovec tcp6_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
> -static struct iovec tcp4_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
> -static struct iovec tcp6_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
> +char tcp_buf_discard [MAX_WINDOW];
>
> /* sendmsg() to socket */
> static struct iovec tcp_iov [UIO_MAXIOV];
> @@ -552,14 +416,6 @@ static uint32_t tcp_conn_epoll_events(uint8_t events, uint8_t conn_flags)
> return EPOLLRDHUP;
> }
>
> -static void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
> - unsigned long flag);
> -#define conn_flag(c, conn, flag) \
> - do { \
> - flow_trace(conn, "flag at %s:%i", __func__, __LINE__); \
> - conn_flag_do(c, conn, flag); \
> - } while (0)
> -
> /**
> * tcp_epoll_ctl() - Add/modify/delete epoll state from connection events
> * @c: Execution context
> @@ -671,8 +527,8 @@ static void tcp_timer_ctl(const struct ctx *c, struct tcp_tap_conn *conn)
> * @conn: Connection pointer
> * @flag: Flag to set, or ~flag to unset
> */
> -static void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
> - unsigned long flag)
> +void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
> + unsigned long flag)
> {
> if (flag & (flag - 1)) {
> int flag_index = fls(~flag);
> @@ -722,8 +578,8 @@ static void tcp_hash_remove(const struct ctx *c,
> * @conn: Connection pointer
> * @event: Connection event
> */
> -static void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
> - unsigned long event)
> +void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
> + unsigned long event)
> {
> int prev, new, num = fls(event);
>
> @@ -771,12 +627,6 @@ static void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
> tcp_timer_ctl(c, conn);
> }
>
> -#define conn_event(c, conn, event) \
> - do { \
> - flow_trace(conn, "event at %s:%i", __func__, __LINE__); \
> - conn_event_do(c, conn, event); \
> - } while (0)
> -
> /**
> * tcp_rtt_dst_low() - Check if low RTT was seen for connection endpoint
> * @conn: Connection pointer
> @@ -906,104 +756,6 @@ static void tcp_update_check_tcp6(struct ipv6hdr *ip6h, struct tcphdr *th)
> th->check = csum(th, l4len, sum);
> }
>
> -/**
> - * tcp_update_l2_buf() - Update Ethernet header buffers with addresses
> - * @eth_d: Ethernet destination address, NULL if unchanged
> - * @eth_s: Ethernet source address, NULL if unchanged
> - */
> -void tcp_update_l2_buf(const unsigned char *eth_d, const unsigned char *eth_s)
> -{
> - eth_update_mac(&tcp4_eth_src, eth_d, eth_s);
> - eth_update_mac(&tcp6_eth_src, eth_d, eth_s);
> -}
> -
> -/**
> - * tcp_sock4_iov_init() - Initialise scatter-gather L2 buffers for IPv4 sockets
> - * @c: Execution context
> - */
> -static void tcp_sock4_iov_init(const struct ctx *c)
> -{
> - struct iphdr iph = L2_BUF_IP4_INIT(IPPROTO_TCP);
> - struct iovec *iov;
> - int i;
> -
> - tcp4_eth_src.h_proto = htons_constant(ETH_P_IP);
> -
> - for (i = 0; i < ARRAY_SIZE(tcp4_payload); i++) {
> - tcp4_payload_ip[i] = iph;
> - tcp4_payload[i].th.doff = sizeof(struct tcphdr) / 4;
> - tcp4_payload[i].th.ack = 1;
> - }
> -
> - for (i = 0; i < ARRAY_SIZE(tcp4_flags); i++) {
> - tcp4_flags_ip[i] = iph;
> - tcp4_flags[i].th.doff = sizeof(struct tcphdr) / 4;
> - tcp4_flags[i].th.ack = 1;
> - }
> -
> - for (i = 0; i < TCP_FRAMES_MEM; i++) {
> - iov = tcp4_l2_iov[i];
> -
> - iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp4_payload_tap_hdr[i]);
> - iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp4_eth_src);
> - iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp4_payload_ip[i]);
> - iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_payload[i];
> - }
> -
> - for (i = 0; i < TCP_FRAMES_MEM; i++) {
> - iov = tcp4_l2_flags_iov[i];
> -
> - iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp4_flags_tap_hdr[i]);
> - iov[TCP_IOV_ETH].iov_base = &tcp4_eth_src;
> - iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp4_eth_src);
> - iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp4_flags_ip[i]);
> - iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_flags[i];
> - }
> -}
> -
> -/**
> - * tcp_sock6_iov_init() - Initialise scatter-gather L2 buffers for IPv6 sockets
> - * @c: Execution context
> - */
> -static void tcp_sock6_iov_init(const struct ctx *c)
> -{
> - struct ipv6hdr ip6 = L2_BUF_IP6_INIT(IPPROTO_TCP);
> - struct iovec *iov;
> - int i;
> -
> - tcp6_eth_src.h_proto = htons_constant(ETH_P_IPV6);
> -
> - for (i = 0; i < ARRAY_SIZE(tcp6_payload); i++) {
> - tcp6_payload_ip[i] = ip6;
> - tcp6_payload[i].th.doff = sizeof(struct tcphdr) / 4;
> - tcp6_payload[i].th.ack = 1;
> - }
> -
> - for (i = 0; i < ARRAY_SIZE(tcp6_flags); i++) {
> - tcp6_flags_ip[i] = ip6;
> - tcp6_flags[i].th.doff = sizeof(struct tcphdr) / 4;
> - tcp6_flags[i].th .ack = 1;
> - }
> -
> - for (i = 0; i < TCP_FRAMES_MEM; i++) {
> - iov = tcp6_l2_iov[i];
> -
> - iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp6_payload_tap_hdr[i]);
> - iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp6_eth_src);
> - iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp6_payload_ip[i]);
> - iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_payload[i];
> - }
> -
> - for (i = 0; i < TCP_FRAMES_MEM; i++) {
> - iov = tcp6_l2_flags_iov[i];
> -
> - iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp6_flags_tap_hdr[i]);
> - iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp6_eth_src);
> - iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp6_flags_ip[i]);
> - iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_flags[i];
> - }
> -}
> -
> /**
> * tcp_opt_get() - Get option, and value if any, from TCP header
> * @opts: Pointer to start of TCP options in header
> @@ -1227,76 +979,6 @@ bool tcp_flow_defer(const struct tcp_tap_conn *conn)
> return true;
> }
>
> -static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn);
> -#define tcp_rst(c, conn) \
> - do { \
> - flow_dbg((conn), "TCP reset at %s:%i", __func__, __LINE__); \
> - tcp_rst_do(c, conn); \
> - } while (0)
> -
> -/**
> - * tcp_flags_flush() - Send out buffers for segments with no data (flags)
> - * @c: Execution context
> - */
> -static void tcp_flags_flush(const struct ctx *c)
> -{
> - tap_send_frames(c, &tcp6_l2_flags_iov[0][0], TCP_NUM_IOVS,
> - tcp6_flags_used);
> - tcp6_flags_used = 0;
> -
> - tap_send_frames(c, &tcp4_l2_flags_iov[0][0], TCP_NUM_IOVS,
> - tcp4_flags_used);
> - tcp4_flags_used = 0;
> -}
> -
> -/**
> - * tcp_revert_seq() - Revert affected conn->seq_to_tap after failed transmission
> - * @conns: Array of connection pointers corresponding to queued frames
> - * @frames: Two-dimensional array containing queued frames with sub-iovs
> - * @num_frames: Number of entries in the two arrays to be compared
> - */
> -static void tcp_revert_seq(struct tcp_tap_conn **conns, struct iovec (*frames)[TCP_NUM_IOVS],
> - int num_frames)
> -{
> - int i;
> -
> - for (i = 0; i < num_frames; i++) {
> - const struct tcphdr *th = frames[i][TCP_IOV_PAYLOAD].iov_base;
> - struct tcp_tap_conn *conn = conns[i];
> - uint32_t seq = ntohl(th->seq);
> -
> - if (SEQ_LE(conn->seq_to_tap, seq))
> - continue;
> -
> - conn->seq_to_tap = seq;
> - }
> -}
> -
> -/**
> - * tcp_payload_flush() - Send out buffers for segments with data
> - * @c: Execution context
> - */
> -static void tcp_payload_flush(const struct ctx *c)
> -{
> - size_t m;
> -
> - m = tap_send_frames(c, &tcp6_l2_iov[0][0], TCP_NUM_IOVS,
> - tcp6_payload_used);
> - if (m != tcp6_payload_used) {
> - tcp_revert_seq(&tcp6_frame_conns[m], &tcp6_l2_iov[m],
> - tcp6_payload_used - m);
> - }
> - tcp6_payload_used = 0;
> -
> - m = tap_send_frames(c, &tcp4_l2_iov[0][0], TCP_NUM_IOVS,
> - tcp4_payload_used);
> - if (m != tcp4_payload_used) {
> - tcp_revert_seq(&tcp4_frame_conns[m], &tcp4_l2_iov[m],
> - tcp4_payload_used - m);
> - }
> - tcp4_payload_used = 0;
> -}
> -
> /**
> * tcp_defer_handler() - Handler for TCP deferred tasks
> * @c: Execution context
> @@ -1430,10 +1112,10 @@ static size_t tcp_fill_headers6(const struct ctx *c,
> *
> * Return: IP payload length, host order
> */
> -static size_t tcp_l2_buf_fill_headers(const struct ctx *c,
> - const struct tcp_tap_conn *conn,
> - struct iovec *iov, size_t dlen,
> - const uint16_t *check, uint32_t seq)
> +size_t tcp_l2_buf_fill_headers(const struct ctx *c,
> + const struct tcp_tap_conn *conn,
> + struct iovec *iov, size_t dlen,
> + const uint16_t *check, uint32_t seq)
> {
> const struct in_addr *a4 = inany_v4(&conn->faddr);
>
> @@ -1459,8 +1141,8 @@ static size_t tcp_l2_buf_fill_headers(const struct ctx *c,
> *
> * Return: 1 if sequence or window were updated, 0 otherwise
> */
> -static int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn,
> - int force_seq, struct tcp_info *tinfo)
> +int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn,
> + int force_seq, struct tcp_info *tinfo)
> {
> uint32_t prev_wnd_to_tap = conn->wnd_to_tap << conn->ws_to_tap;
> uint32_t prev_ack_to_tap = conn->seq_ack_to_tap;
> @@ -1579,9 +1261,9 @@ static void tcp_update_seqack_from_tap(const struct ctx *c,
> * 0 if there is no flag to send
> * 1 otherwise
> */
> -static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> - int flags, struct tcphdr *th, char *data,
> - size_t *optlen)
> +int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> + int flags, struct tcphdr *th, char *data,
> + size_t *optlen)
> {
> struct tcp_info tinfo = { 0 };
> socklen_t sl = sizeof(tinfo);
> @@ -1678,54 +1360,9 @@ static int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn,
> *
> * Return: negative error code on connection reset, 0 otherwise
> */
> -static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> +int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> {
> - struct tcp_flags_t *payload;
> - struct iovec *iov;
> - size_t optlen;
> - size_t l4len;
> - int ret;
> -
> - if (CONN_V4(conn))
> - iov = tcp4_l2_flags_iov[tcp4_flags_used++];
> - else
> - iov = tcp6_l2_flags_iov[tcp6_flags_used++];
> -
> - payload = iov[TCP_IOV_PAYLOAD].iov_base;
> -
> - ret = tcp_prepare_flags(c, conn, flags, &payload->th,
> - payload->opts, &optlen);
> - if (ret <= 0)
> - return ret;
> -
> - l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
> - conn->seq_to_tap);
> - iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> -
> - if (flags & DUP_ACK) {
> - struct iovec *dup_iov;
> - int i;
> -
> - if (CONN_V4(conn))
> - dup_iov = tcp4_l2_flags_iov[tcp4_flags_used++];
> - else
> - dup_iov = tcp6_l2_flags_iov[tcp6_flags_used++];
> -
> - for (i = 0; i < TCP_NUM_IOVS; i++)
> - memcpy(dup_iov[i].iov_base, iov[i].iov_base,
> - iov[i].iov_len);
> - dup_iov[TCP_IOV_PAYLOAD].iov_len = iov[TCP_IOV_PAYLOAD].iov_len;
> - }
> -
> - if (CONN_V4(conn)) {
> - if (tcp4_flags_used > TCP_FRAMES_MEM - 2)
> - tcp_flags_flush(c);
> - } else {
> - if (tcp6_flags_used > TCP_FRAMES_MEM - 2)
> - tcp_flags_flush(c);
> - }
> -
> - return 0;
> + return tcp_buf_send_flag(c, conn, flags);
> }
>
> /**
> @@ -1733,7 +1370,7 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> * @c: Execution context
> * @conn: Connection pointer
> */
> -static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn)
> +void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn)
> {
> if (conn->events == CLOSED)
> return;
> @@ -2160,49 +1797,6 @@ static int tcp_sock_consume(const struct tcp_tap_conn *conn, uint32_t ack_seq)
> return 0;
> }
>
> -/**
> - * tcp_data_to_tap() - Finalise (queue) highest-numbered scatter-gather buffer
> - * @c: Execution context
> - * @conn: Connection pointer
> - * @dlen: TCP payload length
> - * @no_csum: Don't compute IPv4 checksum, use the one from previous buffer
> - * @seq: Sequence number to be sent
> - */
> -static void tcp_data_to_tap(const struct ctx *c, struct tcp_tap_conn *conn,
> - ssize_t dlen, int no_csum, uint32_t seq)
> -{
> - struct iovec *iov;
> - size_t l4len;
> -
> - conn->seq_to_tap = seq + dlen;
> -
> - if (CONN_V4(conn)) {
> - struct iovec *iov_prev = tcp4_l2_iov[tcp4_payload_used - 1];
> - const uint16_t *check = NULL;
> -
> - if (no_csum) {
> - struct iphdr *iph = iov_prev[TCP_IOV_IP].iov_base;
> - check = &iph->check;
> - }
> -
> - tcp4_frame_conns[tcp4_payload_used] = conn;
> -
> - iov = tcp4_l2_iov[tcp4_payload_used++];
> - l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, check, seq);
> - iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> - if (tcp4_payload_used > TCP_FRAMES_MEM - 1)
> - tcp_payload_flush(c);
> - } else if (CONN_V6(conn)) {
> - tcp6_frame_conns[tcp6_payload_used] = conn;
> -
> - iov = tcp6_l2_iov[tcp6_payload_used++];
> - l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, NULL, seq);
> - iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> - if (tcp6_payload_used > TCP_FRAMES_MEM - 1)
> - tcp_payload_flush(c);
> - }
> -}
> -
> /**
> * tcp_data_from_sock() - Handle new data from socket, queue to tap, in window
> * @c: Execution context
> @@ -2214,123 +1808,7 @@ static void tcp_data_to_tap(const struct ctx *c, struct tcp_tap_conn *conn,
> */
> static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn)
> {
> - uint32_t wnd_scaled = conn->wnd_from_tap << conn->ws_from_tap;
> - int fill_bufs, send_bufs = 0, last_len, iov_rem = 0;
> - int sendlen, len, dlen, v4 = CONN_V4(conn);
> - int s = conn->sock, i, ret = 0;
> - struct msghdr mh_sock = { 0 };
> - uint16_t mss = MSS_GET(conn);
> - uint32_t already_sent, seq;
> - struct iovec *iov;
> -
> - already_sent = conn->seq_to_tap - conn->seq_ack_from_tap;
> -
> - if (SEQ_LT(already_sent, 0)) {
> - /* RFC 761, section 2.1. */
> - flow_trace(conn, "ACK sequence gap: ACK for %u, sent: %u",
> - conn->seq_ack_from_tap, conn->seq_to_tap);
> - conn->seq_to_tap = conn->seq_ack_from_tap;
> - already_sent = 0;
> - }
> -
> - if (!wnd_scaled || already_sent >= wnd_scaled) {
> - conn_flag(c, conn, STALLED);
> - conn_flag(c, conn, ACK_FROM_TAP_DUE);
> - return 0;
> - }
> -
> - /* Set up buffer descriptors we'll fill completely and partially. */
> - fill_bufs = DIV_ROUND_UP(wnd_scaled - already_sent, mss);
> - if (fill_bufs > TCP_FRAMES) {
> - fill_bufs = TCP_FRAMES;
> - iov_rem = 0;
> - } else {
> - iov_rem = (wnd_scaled - already_sent) % mss;
> - }
> -
> - mh_sock.msg_iov = iov_sock;
> - mh_sock.msg_iovlen = fill_bufs + 1;
> -
> - iov_sock[0].iov_base = tcp_buf_discard;
> - iov_sock[0].iov_len = already_sent;
> -
> - if (( v4 && tcp4_payload_used + fill_bufs > TCP_FRAMES_MEM) ||
> - (!v4 && tcp6_payload_used + fill_bufs > TCP_FRAMES_MEM)) {
> - tcp_payload_flush(c);
> -
> - /* Silence Coverity CWE-125 false positive */
> - tcp4_payload_used = tcp6_payload_used = 0;
> - }
> -
> - for (i = 0, iov = iov_sock + 1; i < fill_bufs; i++, iov++) {
> - if (v4)
> - iov->iov_base = &tcp4_payload[tcp4_payload_used + i].data;
> - else
> - iov->iov_base = &tcp6_payload[tcp6_payload_used + i].data;
> - iov->iov_len = mss;
> - }
> - if (iov_rem)
> - iov_sock[fill_bufs].iov_len = iov_rem;
> -
> - /* Receive into buffers, don't dequeue until acknowledged by guest. */
> - do
> - len = recvmsg(s, &mh_sock, MSG_PEEK);
> - while (len < 0 && errno == EINTR);
> -
> - if (len < 0)
> - goto err;
> -
> - if (!len) {
> - if ((conn->events & (SOCK_FIN_RCVD | TAP_FIN_SENT)) == SOCK_FIN_RCVD) {
> - if ((ret = tcp_send_flag(c, conn, FIN | ACK))) {
> - tcp_rst(c, conn);
> - return ret;
> - }
> -
> - conn_event(c, conn, TAP_FIN_SENT);
> - }
> -
> - return 0;
> - }
> -
> - sendlen = len - already_sent;
> - if (sendlen <= 0) {
> - conn_flag(c, conn, STALLED);
> - return 0;
> - }
> -
> - conn_flag(c, conn, ~STALLED);
> -
> - send_bufs = DIV_ROUND_UP(sendlen, mss);
> - last_len = sendlen - (send_bufs - 1) * mss;
> -
> - /* Likely, some new data was acked too. */
> - tcp_update_seqack_wnd(c, conn, 0, NULL);
> -
> - /* Finally, queue to tap */
> - dlen = mss;
> - seq = conn->seq_to_tap;
> - for (i = 0; i < send_bufs; i++) {
> - int no_csum = i && i != send_bufs - 1 && tcp4_payload_used;
> -
> - if (i == send_bufs - 1)
> - dlen = last_len;
> -
> - tcp_data_to_tap(c, conn, dlen, no_csum, seq);
> - seq += dlen;
> - }
> -
> - conn_flag(c, conn, ACK_FROM_TAP_DUE);
> -
> - return 0;
> -
> -err:
> - if (errno != EAGAIN && errno != EWOULDBLOCK) {
> - ret = -errno;
> - tcp_rst(c, conn);
> - }
> -
> - return ret;
> + return tcp_buf_data_from_sock(c, conn);
> }
>
> /**
> diff --git a/tcp_buf.c b/tcp_buf.c
> new file mode 100644
> index 000000000000..0c7d07b8d0bd
> --- /dev/null
> +++ b/tcp_buf.c
> @@ -0,0 +1,513 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +
> +/* PASST - Plug A Simple Socket Transport
> + * for qemu/UNIX domain socket mode
> + *
> + * PASTA - Pack A Subtle Tap Abstraction
> + * for network namespace/tap device mode
> + *
> + * tcp_buf.c - TCP L2-L4 buffer management functions
This still has "L2-L4", but L4 doesn't really make sense I think. I can
also drop "-L4" on merge.
> + *
> + * Copyright Red Hat
> + * Author: Stefano Brivio <sbrivio@redhat.com>
> + */
> +
> +#include <stddef.h>
> +#include <stdint.h>
> +#include <limits.h>
> +#include <string.h>
> +#include <errno.h>
> +
> +#include <netinet/ip.h>
> +
> +#include <linux/tcp.h>
> +
> +#include "util.h"
> +#include "ip.h"
> +#include "iov.h"
> +#include "passt.h"
> +#include "tap.h"
> +#include "siphash.h"
> +#include "inany.h"
> +#include "tcp_conn.h"
> +#include "tcp_internal.h"
> +#include "tcp_buf.h"
> +
> +#define TCP_FRAMES_MEM 128
> +#define TCP_FRAMES \
> + (c->mode == MODE_PASST ? TCP_FRAMES_MEM : 1)
> +
> +/* Static buffers */
> +/**
> + * struct tcp_payload_t - TCP header and data to send segments with payload
> + * @th: TCP header
> + * @data: TCP data
> + */
> +struct tcp_payload_t {
> + struct tcphdr th;
> + uint8_t data[IP_MAX_MTU - sizeof(struct tcphdr)];
> +#ifdef __AVX2__
> +} __attribute__ ((packed, aligned(32))); /* For AVX2 checksum routines */
> +#else
> +} __attribute__ ((packed, aligned(__alignof__(unsigned int))));
> +#endif
> +
> +/**
> + * struct tcp_flags_t - TCP header and data to send zero-length
> + * segments (flags)
> + * @th: TCP header
> + * @opts TCP options
> + */
> +struct tcp_flags_t {
> + struct tcphdr th;
> + char opts[OPT_MSS_LEN + OPT_WS_LEN + 1];
> +#ifdef __AVX2__
> +} __attribute__ ((packed, aligned(32)));
> +#else
> +} __attribute__ ((packed, aligned(__alignof__(unsigned int))));
> +#endif
> +
> +/* Ethernet header for IPv4 frames */
> +static struct ethhdr tcp4_eth_src;
> +
> +static struct tap_hdr tcp4_payload_tap_hdr[TCP_FRAMES_MEM];
> +/* IPv4 headers */
> +static struct iphdr tcp4_payload_ip[TCP_FRAMES_MEM];
> +/* TCP segments with payload for IPv4 frames */
> +static struct tcp_payload_t tcp4_payload[TCP_FRAMES_MEM];
> +
> +static_assert(MSS4 <= sizeof(tcp4_payload[0].data), "MSS4 is greater than 65516");
> +
> +/* References tracking the owner connection of frames in the tap outqueue */
> +static struct tcp_tap_conn *tcp4_frame_conns[TCP_FRAMES_MEM];
> +static unsigned int tcp4_payload_used;
> +
> +static struct tap_hdr tcp4_flags_tap_hdr[TCP_FRAMES_MEM];
> +/* IPv4 headers for TCP segment without payload */
> +static struct iphdr tcp4_flags_ip[TCP_FRAMES_MEM];
> +/* TCP segments without payload for IPv4 frames */
> +static struct tcp_flags_t tcp4_flags[TCP_FRAMES_MEM];
> +
> +static unsigned int tcp4_flags_used;
> +
> +/* Ethernet header for IPv6 frames */
> +static struct ethhdr tcp6_eth_src;
> +
> +static struct tap_hdr tcp6_payload_tap_hdr[TCP_FRAMES_MEM];
> +/* IPv6 headers */
> +static struct ipv6hdr tcp6_payload_ip[TCP_FRAMES_MEM];
> +/* TCP headers and data for IPv6 frames */
> +static struct tcp_payload_t tcp6_payload[TCP_FRAMES_MEM];
> +
> +static_assert(MSS6 <= sizeof(tcp6_payload[0].data), "MSS6 is greater than 65516");
> +
> +/* References tracking the owner connection of frames in the tap outqueue */
> +static struct tcp_tap_conn *tcp6_frame_conns[TCP_FRAMES_MEM];
> +static unsigned int tcp6_payload_used;
> +
> +static struct tap_hdr tcp6_flags_tap_hdr[TCP_FRAMES_MEM];
> +/* IPv6 headers for TCP segment without payload */
> +static struct ipv6hdr tcp6_flags_ip[TCP_FRAMES_MEM];
> +/* TCP segment without payload for IPv6 frames */
> +static struct tcp_flags_t tcp6_flags[TCP_FRAMES_MEM];
> +
> +static unsigned int tcp6_flags_used;
> +
> +/* recvmsg()/sendmsg() data for tap */
> +static struct iovec iov_sock [TCP_FRAMES_MEM + 1];
> +
> +static struct iovec tcp4_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
> +static struct iovec tcp6_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
> +static struct iovec tcp4_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
> +static struct iovec tcp6_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS];
> +/**
> + * tcp_update_l2_buf() - Update Ethernet header buffers with addresses
> + * @eth_d: Ethernet destination address, NULL if unchanged
> + * @eth_s: Ethernet source address, NULL if unchanged
> + */
> +void tcp_update_l2_buf(const unsigned char *eth_d, const unsigned char *eth_s)
> +{
> + eth_update_mac(&tcp4_eth_src, eth_d, eth_s);
> + eth_update_mac(&tcp6_eth_src, eth_d, eth_s);
> +}
> +
> +/**
> + * tcp_sock4_iov_init() - Initialise scatter-gather L2 buffers for IPv4 sockets
> + * @c: Execution context
> + */
> +void tcp_sock4_iov_init(const struct ctx *c)
> +{
> + struct iphdr iph = L2_BUF_IP4_INIT(IPPROTO_TCP);
> + struct iovec *iov;
> + int i;
> +
> + tcp4_eth_src.h_proto = htons_constant(ETH_P_IP);
> +
> + for (i = 0; i < ARRAY_SIZE(tcp4_payload); i++) {
> + tcp4_payload_ip[i] = iph;
> + tcp4_payload[i].th.doff = sizeof(struct tcphdr) / 4;
> + tcp4_payload[i].th.ack = 1;
> + }
> +
> + for (i = 0; i < ARRAY_SIZE(tcp4_flags); i++) {
> + tcp4_flags_ip[i] = iph;
> + tcp4_flags[i].th.doff = sizeof(struct tcphdr) / 4;
> + tcp4_flags[i].th.ack = 1;
> + }
> +
> + for (i = 0; i < TCP_FRAMES_MEM; i++) {
> + iov = tcp4_l2_iov[i];
> +
> + iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp4_payload_tap_hdr[i]);
> + iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp4_eth_src);
> + iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp4_payload_ip[i]);
> + iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_payload[i];
> + }
> +
> + for (i = 0; i < TCP_FRAMES_MEM; i++) {
> + iov = tcp4_l2_flags_iov[i];
> +
> + iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp4_flags_tap_hdr[i]);
> + iov[TCP_IOV_ETH].iov_base = &tcp4_eth_src;
> + iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp4_eth_src);
> + iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp4_flags_ip[i]);
> + iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_flags[i];
> + }
> +}
> +
> +/**
> + * tcp_sock6_iov_init() - Initialise scatter-gather L2 buffers for IPv6 sockets
> + * @c: Execution context
> + */
> +void tcp_sock6_iov_init(const struct ctx *c)
> +{
> + struct ipv6hdr ip6 = L2_BUF_IP6_INIT(IPPROTO_TCP);
> + struct iovec *iov;
> + int i;
> +
> + tcp6_eth_src.h_proto = htons_constant(ETH_P_IPV6);
> +
> + for (i = 0; i < ARRAY_SIZE(tcp6_payload); i++) {
> + tcp6_payload_ip[i] = ip6;
> + tcp6_payload[i].th.doff = sizeof(struct tcphdr) / 4;
> + tcp6_payload[i].th.ack = 1;
> + }
> +
> + for (i = 0; i < ARRAY_SIZE(tcp6_flags); i++) {
> + tcp6_flags_ip[i] = ip6;
> + tcp6_flags[i].th.doff = sizeof(struct tcphdr) / 4;
> + tcp6_flags[i].th .ack = 1;
> + }
> +
> + for (i = 0; i < TCP_FRAMES_MEM; i++) {
> + iov = tcp6_l2_iov[i];
> +
> + iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp6_payload_tap_hdr[i]);
> + iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp6_eth_src);
> + iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp6_payload_ip[i]);
> + iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_payload[i];
> + }
> +
> + for (i = 0; i < TCP_FRAMES_MEM; i++) {
> + iov = tcp6_l2_flags_iov[i];
> +
> + iov[TCP_IOV_TAP] = tap_hdr_iov(c, &tcp6_flags_tap_hdr[i]);
> + iov[TCP_IOV_ETH] = IOV_OF_LVALUE(tcp6_eth_src);
> + iov[TCP_IOV_IP] = IOV_OF_LVALUE(tcp6_flags_ip[i]);
> + iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_flags[i];
> + }
> +}
> +
> +/**
> + * tcp_flags_flush() - Send out buffers for segments with no data (flags)
> + * @c: Execution context
> + */
> +void tcp_flags_flush(const struct ctx *c)
> +{
> + tap_send_frames(c, &tcp6_l2_flags_iov[0][0], TCP_NUM_IOVS,
> + tcp6_flags_used);
> + tcp6_flags_used = 0;
> +
> + tap_send_frames(c, &tcp4_l2_flags_iov[0][0], TCP_NUM_IOVS,
> + tcp4_flags_used);
> + tcp4_flags_used = 0;
> +}
> +
> +/**
> + * tcp_revert_seq() - Revert affected conn->seq_to_tap after failed transmission
> + * @conns: Array of connection pointers corresponding to queued frames
> + * @frames: Two-dimensional array containing queued frames with sub-iovs
> + * @num_frames: Number of entries in the two arrays to be compared
> + */
> +static void tcp_revert_seq(struct tcp_tap_conn **conns, struct iovec (*frames)[TCP_NUM_IOVS],
> + int num_frames)
> +{
> + int i;
> +
> + for (i = 0; i < num_frames; i++) {
> + const struct tcphdr *th = frames[i][TCP_IOV_PAYLOAD].iov_base;
> + struct tcp_tap_conn *conn = conns[i];
> + uint32_t seq = ntohl(th->seq);
> +
> + if (SEQ_LE(conn->seq_to_tap, seq))
> + continue;
> +
> + conn->seq_to_tap = seq;
> + }
> +}
> +
> +/**
> + * tcp_payload_flush() - Send out buffers for segments with data
> + * @c: Execution context
> + */
> +void tcp_payload_flush(const struct ctx *c)
> +{
> + size_t m;
> +
> + m = tap_send_frames(c, &tcp6_l2_iov[0][0], TCP_NUM_IOVS,
> + tcp6_payload_used);
> + if (m != tcp6_payload_used) {
> + tcp_revert_seq(&tcp6_frame_conns[m], &tcp6_l2_iov[m],
> + tcp6_payload_used - m);
> + }
> + tcp6_payload_used = 0;
> +
> + m = tap_send_frames(c, &tcp4_l2_iov[0][0], TCP_NUM_IOVS,
> + tcp4_payload_used);
> + if (m != tcp4_payload_used) {
> + tcp_revert_seq(&tcp4_frame_conns[m], &tcp4_l2_iov[m],
> + tcp4_payload_used - m);
> + }
> + tcp4_payload_used = 0;
> +}
> +
> +/**
> + * tcp_buf_send_flag() - Send segment with flags to tap (no payload)
> + * @c: Execution context
> + * @conn: Connection pointer
> + * @flags: TCP flags: if not set, send segment only if ACK is due
> + *
> + * Return: negative error code on connection reset, 0 otherwise
> + */
> +int tcp_buf_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> +{
> + struct tcp_flags_t *payload;
> + struct iovec *iov;
> + size_t optlen;
> + size_t l4len;
> + int ret;
> +
> + if (CONN_V4(conn))
> + iov = tcp4_l2_flags_iov[tcp4_flags_used++];
> + else
> + iov = tcp6_l2_flags_iov[tcp6_flags_used++];
> +
> + payload = iov[TCP_IOV_PAYLOAD].iov_base;
> +
> + ret = tcp_prepare_flags(c, conn, flags, &payload->th,
> + payload->opts, &optlen);
> + if (ret <= 0)
> + return ret;
> +
> + l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
> + conn->seq_to_tap);
> + iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> +
> + if (flags & DUP_ACK) {
> + struct iovec *dup_iov;
> + int i;
> +
> + if (CONN_V4(conn))
> + dup_iov = tcp4_l2_flags_iov[tcp4_flags_used++];
> + else
> + dup_iov = tcp6_l2_flags_iov[tcp6_flags_used++];
> +
> + for (i = 0; i < TCP_NUM_IOVS; i++)
> + memcpy(dup_iov[i].iov_base, iov[i].iov_base,
> + iov[i].iov_len);
> + dup_iov[TCP_IOV_PAYLOAD].iov_len = iov[TCP_IOV_PAYLOAD].iov_len;
> + }
> +
> + if (CONN_V4(conn)) {
> + if (tcp4_flags_used > TCP_FRAMES_MEM - 2)
> + tcp_flags_flush(c);
> + } else {
> + if (tcp6_flags_used > TCP_FRAMES_MEM - 2)
> + tcp_flags_flush(c);
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * tcp_data_to_tap() - Finalise (queue) highest-numbered scatter-gather buffer
> + * @c: Execution context
> + * @conn: Connection pointer
> + * @dlen: TCP payload length
> + * @no_csum: Don't compute IPv4 checksum, use the one from previous buffer
> + * @seq: Sequence number to be sent
> + */
> +static void tcp_data_to_tap(const struct ctx *c, struct tcp_tap_conn *conn,
> + ssize_t dlen, int no_csum, uint32_t seq)
> +{
> + struct iovec *iov;
> + size_t l4len;
> +
> + conn->seq_to_tap = seq + dlen;
> +
> + if (CONN_V4(conn)) {
> + struct iovec *iov_prev = tcp4_l2_iov[tcp4_payload_used - 1];
> + const uint16_t *check = NULL;
> +
> + if (no_csum) {
> + struct iphdr *iph = iov_prev[TCP_IOV_IP].iov_base;
> + check = &iph->check;
> + }
> +
> + tcp4_frame_conns[tcp4_payload_used] = conn;
> +
> + iov = tcp4_l2_iov[tcp4_payload_used++];
> + l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, check, seq);
> + iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> + if (tcp4_payload_used > TCP_FRAMES_MEM - 1)
> + tcp_payload_flush(c);
> + } else if (CONN_V6(conn)) {
> + tcp6_frame_conns[tcp6_payload_used] = conn;
> +
> + iov = tcp6_l2_iov[tcp6_payload_used++];
> + l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, NULL, seq);
> + iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> + if (tcp6_payload_used > TCP_FRAMES_MEM - 1)
> + tcp_payload_flush(c);
> + }
> +}
> +
> +/**
> + * tcp_buf_data_from_sock() - Handle new data from socket, queue to tap, in window
> + * @c: Execution context
> + * @conn: Connection pointer
> + *
> + * Return: negative on connection reset, 0 otherwise
> + *
> + * #syscalls recvmsg
> + */
> +int tcp_buf_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn)
> +{
> + uint32_t wnd_scaled = conn->wnd_from_tap << conn->ws_from_tap;
> + int fill_bufs, send_bufs = 0, last_len, iov_rem = 0;
> + int sendlen, len, dlen, v4 = CONN_V4(conn);
> + int s = conn->sock, i, ret = 0;
> + struct msghdr mh_sock = { 0 };
> + uint16_t mss = MSS_GET(conn);
> + uint32_t already_sent, seq;
> + struct iovec *iov;
> +
> + already_sent = conn->seq_to_tap - conn->seq_ack_from_tap;
> +
> + if (SEQ_LT(already_sent, 0)) {
> + /* RFC 761, section 2.1. */
> + flow_trace(conn, "ACK sequence gap: ACK for %u, sent: %u",
> + conn->seq_ack_from_tap, conn->seq_to_tap);
> + conn->seq_to_tap = conn->seq_ack_from_tap;
> + already_sent = 0;
> + }
> +
> + if (!wnd_scaled || already_sent >= wnd_scaled) {
> + conn_flag(c, conn, STALLED);
> + conn_flag(c, conn, ACK_FROM_TAP_DUE);
> + return 0;
> + }
> +
> + /* Set up buffer descriptors we'll fill completely and partially. */
> + fill_bufs = DIV_ROUND_UP(wnd_scaled - already_sent, mss);
> + if (fill_bufs > TCP_FRAMES) {
> + fill_bufs = TCP_FRAMES;
> + iov_rem = 0;
> + } else {
> + iov_rem = (wnd_scaled - already_sent) % mss;
> + }
> +
> + mh_sock.msg_iov = iov_sock;
> + mh_sock.msg_iovlen = fill_bufs + 1;
> +
> + iov_sock[0].iov_base = tcp_buf_discard;
> + iov_sock[0].iov_len = already_sent;
> +
> + if (( v4 && tcp4_payload_used + fill_bufs > TCP_FRAMES_MEM) ||
> + (!v4 && tcp6_payload_used + fill_bufs > TCP_FRAMES_MEM)) {
> + tcp_payload_flush(c);
> +
> + /* Silence Coverity CWE-125 false positive */
> + tcp4_payload_used = tcp6_payload_used = 0;
> + }
> +
> + for (i = 0, iov = iov_sock + 1; i < fill_bufs; i++, iov++) {
> + if (v4)
> + iov->iov_base = &tcp4_payload[tcp4_payload_used + i].data;
> + else
> + iov->iov_base = &tcp6_payload[tcp6_payload_used + i].data;
> + iov->iov_len = mss;
> + }
> + if (iov_rem)
> + iov_sock[fill_bufs].iov_len = iov_rem;
> +
> + /* Receive into buffers, don't dequeue until acknowledged by guest. */
> + do
> + len = recvmsg(s, &mh_sock, MSG_PEEK);
> + while (len < 0 && errno == EINTR);
> +
> + if (len < 0)
> + goto err;
> +
> + if (!len) {
> + if ((conn->events & (SOCK_FIN_RCVD | TAP_FIN_SENT)) == SOCK_FIN_RCVD) {
> + if ((ret = tcp_buf_send_flag(c, conn, FIN | ACK))) {
> + tcp_rst(c, conn);
> + return ret;
> + }
> +
> + conn_event(c, conn, TAP_FIN_SENT);
> + }
> +
> + return 0;
> + }
> +
> + sendlen = len - already_sent;
> + if (sendlen <= 0) {
> + conn_flag(c, conn, STALLED);
> + return 0;
> + }
> +
> + conn_flag(c, conn, ~STALLED);
> +
> + send_bufs = DIV_ROUND_UP(sendlen, mss);
> + last_len = sendlen - (send_bufs - 1) * mss;
> +
> + /* Likely, some new data was acked too. */
> + tcp_update_seqack_wnd(c, conn, 0, NULL);
> +
> + /* Finally, queue to tap */
> + dlen = mss;
> + seq = conn->seq_to_tap;
> + for (i = 0; i < send_bufs; i++) {
> + int no_csum = i && i != send_bufs - 1 && tcp4_payload_used;
> +
> + if (i == send_bufs - 1)
> + dlen = last_len;
> +
> + tcp_data_to_tap(c, conn, dlen, no_csum, seq);
> + seq += dlen;
> + }
> +
> + conn_flag(c, conn, ACK_FROM_TAP_DUE);
> +
> + return 0;
> +
> +err:
> + if (errno != EAGAIN && errno != EWOULDBLOCK) {
> + ret = -errno;
> + tcp_rst(c, conn);
> + }
> +
> + return ret;
> +}
> diff --git a/tcp_buf.h b/tcp_buf.h
> new file mode 100644
> index 000000000000..14be7b945285
> --- /dev/null
> +++ b/tcp_buf.h
> @@ -0,0 +1,16 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later
> + * Copyright (c) 2021 Red Hat GmbH
> + * Author: Stefano Brivio <sbrivio@redhat.com>
> + */
> +
> +#ifndef TCP_BUF_H
> +#define TCP_BUF_H
> +
> +void tcp_sock4_iov_init(const struct ctx *c);
> +void tcp_sock6_iov_init(const struct ctx *c);
> +void tcp_flags_flush(const struct ctx *c);
> +void tcp_payload_flush(const struct ctx *c);
> +int tcp_buf_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn);
> +int tcp_buf_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags);
> +
> +#endif /*TCP_BUF_H */
> diff --git a/tcp_internal.h b/tcp_internal.h
> new file mode 100644
> index 000000000000..51aaa16918cf
> --- /dev/null
> +++ b/tcp_internal.h
> @@ -0,0 +1,96 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later
> + * Copyright (c) 2021 Red Hat GmbH
> + * Author: Stefano Brivio <sbrivio@redhat.com>
> + */
> +
> +#ifndef TCP_INTERNAL_H
> +#define TCP_INTERNAL_H
> +
> +#define MAX_WS 8
> +#define MAX_WINDOW (1 << (16 + (MAX_WS)))
> +
> +#define MSS4 ROUND_DOWN(IP_MAX_MTU - \
> + sizeof(struct tcphdr) - \
> + sizeof(struct iphdr), \
> + sizeof(uint32_t))
> +#define MSS6 ROUND_DOWN(IP_MAX_MTU - \
> + sizeof(struct tcphdr) - \
> + sizeof(struct ipv6hdr), \
> + sizeof(uint32_t))
> +
> +#define SEQ_LE(a, b) ((b) - (a) < MAX_WINDOW)
> +#define SEQ_LT(a, b) ((b) - (a) - 1 < MAX_WINDOW)
> +#define SEQ_GE(a, b) ((a) - (b) < MAX_WINDOW)
> +#define SEQ_GT(a, b) ((a) - (b) - 1 < MAX_WINDOW)
> +
> +#define FIN (1 << 0)
> +#define SYN (1 << 1)
> +#define RST (1 << 2)
> +#define ACK (1 << 4)
> +
> +/* Flags for internal usage */
> +#define DUP_ACK (1 << 5)
> +#define OPT_EOL 0
> +#define OPT_NOP 1
> +#define OPT_MSS 2
> +#define OPT_MSS_LEN 4
> +#define OPT_WS 3
> +#define OPT_WS_LEN 3
> +#define OPT_SACKP 4
> +#define OPT_SACK 5
> +#define OPT_TS 8
> +#define CONN_V4(conn) (!!inany_v4(&(conn)->faddr))
> +#define CONN_V6(conn) (!CONN_V4(conn))
> +
> +/*
> + * enum tcp_iov_parts - I/O vector parts for one TCP frame
> + * @TCP_IOV_TAP tap backend specific header
> + * @TCP_IOV_ETH Ethernet header
> + * @TCP_IOV_IP IP (v4/v6) header
> + * @TCP_IOV_PAYLOAD IP payload (TCP header + data)
> + * @TCP_NUM_IOVS the number of entries in the iovec array
> + */
> +enum tcp_iov_parts {
> + TCP_IOV_TAP = 0,
> + TCP_IOV_ETH = 1,
> + TCP_IOV_IP = 2,
> + TCP_IOV_PAYLOAD = 3,
> + TCP_NUM_IOVS
> +};
> +
> +extern char tcp_buf_discard [MAX_WINDOW];
> +
> +void conn_flag_do(const struct ctx *c, struct tcp_tap_conn *conn,
> + unsigned long flag);
> +#define conn_flag(c, conn, flag) \
> + do { \
> + flow_trace(conn, "flag at %s:%i", __func__, __LINE__); \
> + conn_flag_do(c, conn, flag); \
> + } while (0)
> +
> +
> +void conn_event_do(const struct ctx *c, struct tcp_tap_conn *conn,
> + unsigned long event);
> +#define conn_event(c, conn, event) \
> + do { \
> + flow_trace(conn, "event at %s:%i", __func__, __LINE__); \
> + conn_event_do(c, conn, event); \
> + } while (0)
> +
> +void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn);
> +#define tcp_rst(c, conn) \
> + do { \
> + flow_dbg((conn), "TCP reset at %s:%i", __func__, __LINE__); \
> + tcp_rst_do(c, conn); \
> + } while (0)
> +
> +size_t tcp_l2_buf_fill_headers(const struct ctx *c,
> + const struct tcp_tap_conn *conn,
> + struct iovec *iov, size_t dlen,
> + const uint16_t *check, uint32_t seq);
> +int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn,
> + int force_seq, struct tcp_info *tinfo);
> +int tcp_prepare_flags(struct ctx *c, struct tcp_tap_conn *conn, int flags,
> + struct tcphdr *th, char *data, size_t *optlen);
> +
> +#endif /* TCP_INTERNAL_H */
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH v6 3/8] tap: refactor packets handling functions
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
2024-06-12 15:47 ` [PATCH v6 1/8] tcp: extract buffer management from tcp_send_flag() Laurent Vivier
2024-06-12 15:47 ` [PATCH v6 2/8] tcp: move buffers management functions to their own file Laurent Vivier
@ 2024-06-12 15:47 ` Laurent Vivier
2024-06-12 15:52 ` Stefano Brivio
2024-06-12 15:47 ` [PATCH v6 4/8] udp: refactor UDP header update functions Laurent Vivier
` (5 subsequent siblings)
8 siblings, 1 reply; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 15:47 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Consolidate pool_tap4() and pool_tap6() into tap_flush_pools(),
and tap4_handler() and tap6_handler() into tap_handler().
Create a generic tap_add_packet() to consolidate packet
addition logic and reduce code duplication.
The purpose is to ease the export of these functions to use
them with the vhost-user backend.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
Notes:
v6:
- rename tap_handler_all() to tap_handler()
- rename packet_add_all_do() to tap_add_packet
and remove func and line.
- rename pool_flush_all() to tap_flush_pools()
v5:
- update commit message and function comments
tap.c | 112 +++++++++++++++++++++++++++++++++-------------------------
tap.h | 3 ++
2 files changed, 66 insertions(+), 49 deletions(-)
diff --git a/tap.c b/tap.c
index 26084b486519..ec3a0d68ea2f 100644
--- a/tap.c
+++ b/tap.c
@@ -921,6 +921,60 @@ append:
return in->count;
}
+/**
+ * pool_flush() - Flush both IPv4 and IPv6 packet pools
+ */
+void tap_flush_pools(void)
+{
+ pool_flush(pool_tap4);
+ pool_flush(pool_tap6);
+}
+
+/**
+ * tap_handler() - IPv4/IPv6 and ARP packet handler for tap file descriptor
+ * @c: Execution context
+ * @now: Current timestamp
+ */
+void tap_handler(struct ctx *c, const struct timespec *now)
+{
+ tap4_handler(c, pool_tap4, now);
+ tap6_handler(c, pool_tap6, now);
+}
+
+/**
+ * tap_add_packet() - Queue/capture packet, update notion of guest MAC address
+ * @c: Execution context
+ * @l2len: Total L2 packet length
+ * @p: Packet buffer
+ * @func: For tracing: name of calling function, NULL means no trace()
+ * @line: For tracing: caller line of function call
+ */
+void tap_add_packet(struct ctx *c, ssize_t l2len, char *p)
+{
+ const struct ethhdr *eh;
+
+ pcap(p, l2len);
+
+ eh = (struct ethhdr *)p;
+
+ if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
+ memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
+ proto_update_l2_buf(c->mac_guest, NULL);
+ }
+
+ switch (ntohs(eh->h_proto)) {
+ case ETH_P_ARP:
+ case ETH_P_IP:
+ packet_add(pool_tap4, l2len, p);
+ break;
+ case ETH_P_IPV6:
+ packet_add(pool_tap6, l2len, p);
+ break;
+ default:
+ break;
+ }
+}
+
/**
* tap_sock_reset() - Handle closing or failure of connect AF_UNIX socket
* @c: Execution context
@@ -947,7 +1001,6 @@ static void tap_sock_reset(struct ctx *c)
void tap_handler_passt(struct ctx *c, uint32_t events,
const struct timespec *now)
{
- const struct ethhdr *eh;
ssize_t n, rem;
char *p;
@@ -960,8 +1013,7 @@ redo:
p = pkt_buf;
rem = 0;
- pool_flush(pool_tap4);
- pool_flush(pool_tap6);
+ tap_flush_pools();
n = recv(c->fd_tap, p, TAP_BUF_FILL, MSG_DONTWAIT);
if (n < 0) {
@@ -988,38 +1040,18 @@ redo:
/* Complete the partial read above before discarding a malformed
* frame, otherwise the stream will be inconsistent.
*/
- if (l2len < (ssize_t)sizeof(*eh) ||
+ if (l2len < (ssize_t)sizeof(struct ethhdr) ||
l2len > (ssize_t)ETH_MAX_MTU)
goto next;
- pcap(p, l2len);
-
- eh = (struct ethhdr *)p;
-
- if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
- memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
- proto_update_l2_buf(c->mac_guest, NULL);
- }
-
- switch (ntohs(eh->h_proto)) {
- case ETH_P_ARP:
- case ETH_P_IP:
- packet_add(pool_tap4, l2len, p);
- break;
- case ETH_P_IPV6:
- packet_add(pool_tap6, l2len, p);
- break;
- default:
- break;
- }
+ tap_add_packet(c, l2len, p);
next:
p += l2len;
n -= l2len;
}
- tap4_handler(c, pool_tap4, now);
- tap6_handler(c, pool_tap6, now);
+ tap_handler(c, now);
/* We can't use EPOLLET otherwise. */
if (rem)
@@ -1044,35 +1076,18 @@ void tap_handler_pasta(struct ctx *c, uint32_t events,
redo:
n = 0;
- pool_flush(pool_tap4);
- pool_flush(pool_tap6);
+ tap_flush_pools();
restart:
while ((len = read(c->fd_tap, pkt_buf + n, TAP_BUF_BYTES - n)) > 0) {
- const struct ethhdr *eh = (struct ethhdr *)(pkt_buf + n);
- if (len < (ssize_t)sizeof(*eh) || len > (ssize_t)ETH_MAX_MTU) {
+ if (len < (ssize_t)sizeof(struct ethhdr) ||
+ len > (ssize_t)ETH_MAX_MTU) {
n += len;
continue;
}
- pcap(pkt_buf + n, len);
- if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
- memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
- proto_update_l2_buf(c->mac_guest, NULL);
- }
-
- switch (ntohs(eh->h_proto)) {
- case ETH_P_ARP:
- case ETH_P_IP:
- packet_add(pool_tap4, len, pkt_buf + n);
- break;
- case ETH_P_IPV6:
- packet_add(pool_tap6, len, pkt_buf + n);
- break;
- default:
- break;
- }
+ tap_add_packet(c, len, pkt_buf + n);
if ((n += len) == TAP_BUF_BYTES)
break;
@@ -1083,8 +1098,7 @@ restart:
ret = errno;
- tap4_handler(c, pool_tap4, now);
- tap6_handler(c, pool_tap6, now);
+ tap_handler(c, now);
if (len > 0 || ret == EAGAIN)
return;
diff --git a/tap.h b/tap.h
index 2285a87093f9..d496bd0e4b99 100644
--- a/tap.h
+++ b/tap.h
@@ -70,5 +70,8 @@ void tap_handler_passt(struct ctx *c, uint32_t events,
const struct timespec *now);
int tap_sock_unix_open(char *sock_path);
void tap_sock_init(struct ctx *c);
+void tap_flush_pools(void);
+void tap_handler(struct ctx *c, const struct timespec *now);
+void tap_add_packet(struct ctx *c, ssize_t l2len, char *p);
#endif /* TAP_H */
--
@@ -70,5 +70,8 @@ void tap_handler_passt(struct ctx *c, uint32_t events,
const struct timespec *now);
int tap_sock_unix_open(char *sock_path);
void tap_sock_init(struct ctx *c);
+void tap_flush_pools(void);
+void tap_handler(struct ctx *c, const struct timespec *now);
+void tap_add_packet(struct ctx *c, ssize_t l2len, char *p);
#endif /* TAP_H */
--
2.45.2
^ permalink raw reply related [flat|nested] 25+ messages in thread* Re: [PATCH v6 3/8] tap: refactor packets handling functions
2024-06-12 15:47 ` [PATCH v6 3/8] tap: refactor packets handling functions Laurent Vivier
@ 2024-06-12 15:52 ` Stefano Brivio
2024-06-12 16:00 ` Laurent Vivier
0 siblings, 1 reply; 25+ messages in thread
From: Stefano Brivio @ 2024-06-12 15:52 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
On Wed, 12 Jun 2024 17:47:29 +0200
Laurent Vivier <lvivier@redhat.com> wrote:
> Consolidate pool_tap4() and pool_tap6() into tap_flush_pools(),
> and tap4_handler() and tap6_handler() into tap_handler().
> Create a generic tap_add_packet() to consolidate packet
> addition logic and reduce code duplication.
>
> The purpose is to ease the export of these functions to use
> them with the vhost-user backend.
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
>
> Notes:
> v6:
> - rename tap_handler_all() to tap_handler()
> - rename packet_add_all_do() to tap_add_packet
> and remove func and line.
Oops, they're still in the comment to the function. I can drop that on
merge.
> - rename pool_flush_all() to tap_flush_pools()
>
> v5:
> - update commit message and function comments
>
> tap.c | 112 +++++++++++++++++++++++++++++++++-------------------------
> tap.h | 3 ++
> 2 files changed, 66 insertions(+), 49 deletions(-)
>
> diff --git a/tap.c b/tap.c
> index 26084b486519..ec3a0d68ea2f 100644
> --- a/tap.c
> +++ b/tap.c
> @@ -921,6 +921,60 @@ append:
> return in->count;
> }
>
> +/**
> + * pool_flush() - Flush both IPv4 and IPv6 packet pools
> + */
> +void tap_flush_pools(void)
> +{
> + pool_flush(pool_tap4);
> + pool_flush(pool_tap6);
> +}
> +
> +/**
> + * tap_handler() - IPv4/IPv6 and ARP packet handler for tap file descriptor
> + * @c: Execution context
> + * @now: Current timestamp
> + */
> +void tap_handler(struct ctx *c, const struct timespec *now)
> +{
> + tap4_handler(c, pool_tap4, now);
> + tap6_handler(c, pool_tap6, now);
> +}
> +
> +/**
> + * tap_add_packet() - Queue/capture packet, update notion of guest MAC address
> + * @c: Execution context
> + * @l2len: Total L2 packet length
> + * @p: Packet buffer
> + * @func: For tracing: name of calling function, NULL means no trace()
> + * @line: For tracing: caller line of function call
> + */
> +void tap_add_packet(struct ctx *c, ssize_t l2len, char *p)
> +{
> + const struct ethhdr *eh;
> +
> + pcap(p, l2len);
> +
> + eh = (struct ethhdr *)p;
> +
> + if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
> + memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
> + proto_update_l2_buf(c->mac_guest, NULL);
> + }
> +
> + switch (ntohs(eh->h_proto)) {
> + case ETH_P_ARP:
> + case ETH_P_IP:
> + packet_add(pool_tap4, l2len, p);
> + break;
> + case ETH_P_IPV6:
> + packet_add(pool_tap6, l2len, p);
> + break;
> + default:
> + break;
> + }
> +}
> +
> /**
> * tap_sock_reset() - Handle closing or failure of connect AF_UNIX socket
> * @c: Execution context
> @@ -947,7 +1001,6 @@ static void tap_sock_reset(struct ctx *c)
> void tap_handler_passt(struct ctx *c, uint32_t events,
> const struct timespec *now)
> {
> - const struct ethhdr *eh;
> ssize_t n, rem;
> char *p;
>
> @@ -960,8 +1013,7 @@ redo:
> p = pkt_buf;
> rem = 0;
>
> - pool_flush(pool_tap4);
> - pool_flush(pool_tap6);
> + tap_flush_pools();
>
> n = recv(c->fd_tap, p, TAP_BUF_FILL, MSG_DONTWAIT);
> if (n < 0) {
> @@ -988,38 +1040,18 @@ redo:
> /* Complete the partial read above before discarding a malformed
> * frame, otherwise the stream will be inconsistent.
> */
> - if (l2len < (ssize_t)sizeof(*eh) ||
> + if (l2len < (ssize_t)sizeof(struct ethhdr) ||
> l2len > (ssize_t)ETH_MAX_MTU)
> goto next;
>
> - pcap(p, l2len);
> -
> - eh = (struct ethhdr *)p;
> -
> - if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
> - memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
> - proto_update_l2_buf(c->mac_guest, NULL);
> - }
> -
> - switch (ntohs(eh->h_proto)) {
> - case ETH_P_ARP:
> - case ETH_P_IP:
> - packet_add(pool_tap4, l2len, p);
> - break;
> - case ETH_P_IPV6:
> - packet_add(pool_tap6, l2len, p);
> - break;
> - default:
> - break;
> - }
> + tap_add_packet(c, l2len, p);
>
> next:
> p += l2len;
> n -= l2len;
> }
>
> - tap4_handler(c, pool_tap4, now);
> - tap6_handler(c, pool_tap6, now);
> + tap_handler(c, now);
>
> /* We can't use EPOLLET otherwise. */
> if (rem)
> @@ -1044,35 +1076,18 @@ void tap_handler_pasta(struct ctx *c, uint32_t events,
> redo:
> n = 0;
>
> - pool_flush(pool_tap4);
> - pool_flush(pool_tap6);
> + tap_flush_pools();
> restart:
> while ((len = read(c->fd_tap, pkt_buf + n, TAP_BUF_BYTES - n)) > 0) {
> - const struct ethhdr *eh = (struct ethhdr *)(pkt_buf + n);
>
> - if (len < (ssize_t)sizeof(*eh) || len > (ssize_t)ETH_MAX_MTU) {
> + if (len < (ssize_t)sizeof(struct ethhdr) ||
> + len > (ssize_t)ETH_MAX_MTU) {
> n += len;
> continue;
> }
>
> - pcap(pkt_buf + n, len);
>
> - if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
> - memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
> - proto_update_l2_buf(c->mac_guest, NULL);
> - }
> -
> - switch (ntohs(eh->h_proto)) {
> - case ETH_P_ARP:
> - case ETH_P_IP:
> - packet_add(pool_tap4, len, pkt_buf + n);
> - break;
> - case ETH_P_IPV6:
> - packet_add(pool_tap6, len, pkt_buf + n);
> - break;
> - default:
> - break;
> - }
> + tap_add_packet(c, len, pkt_buf + n);
>
> if ((n += len) == TAP_BUF_BYTES)
> break;
> @@ -1083,8 +1098,7 @@ restart:
>
> ret = errno;
>
> - tap4_handler(c, pool_tap4, now);
> - tap6_handler(c, pool_tap6, now);
> + tap_handler(c, now);
>
> if (len > 0 || ret == EAGAIN)
> return;
> diff --git a/tap.h b/tap.h
> index 2285a87093f9..d496bd0e4b99 100644
> --- a/tap.h
> +++ b/tap.h
> @@ -70,5 +70,8 @@ void tap_handler_passt(struct ctx *c, uint32_t events,
> const struct timespec *now);
> int tap_sock_unix_open(char *sock_path);
> void tap_sock_init(struct ctx *c);
> +void tap_flush_pools(void);
> +void tap_handler(struct ctx *c, const struct timespec *now);
> +void tap_add_packet(struct ctx *c, ssize_t l2len, char *p);
>
> #endif /* TAP_H */
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 3/8] tap: refactor packets handling functions
2024-06-12 15:52 ` Stefano Brivio
@ 2024-06-12 16:00 ` Laurent Vivier
0 siblings, 0 replies; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 16:00 UTC (permalink / raw)
To: Stefano Brivio; +Cc: passt-dev
On 12/06/2024 17:52, Stefano Brivio wrote:
> On Wed, 12 Jun 2024 17:47:29 +0200
> Laurent Vivier <lvivier@redhat.com> wrote:
>
>> Consolidate pool_tap4() and pool_tap6() into tap_flush_pools(),
>> and tap4_handler() and tap6_handler() into tap_handler().
>> Create a generic tap_add_packet() to consolidate packet
>> addition logic and reduce code duplication.
>>
>> The purpose is to ease the export of these functions to use
>> them with the vhost-user backend.
>>
>> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
>> ---
>>
>> Notes:
>> v6:
>> - rename tap_handler_all() to tap_handler()
>> - rename packet_add_all_do() to tap_add_packet
>> and remove func and line.
>
> Oops, they're still in the comment to the function. I can drop that on
> merge.
yes, please, and also the comment of tap_flush_pools()
Thanks,
Laurent >
>> - rename pool_flush_all() to tap_flush_pools()
>>
>> v5:
>> - update commit message and function comments
>>
>> tap.c | 112 +++++++++++++++++++++++++++++++++-------------------------
>> tap.h | 3 ++
>> 2 files changed, 66 insertions(+), 49 deletions(-)
>>
>> diff --git a/tap.c b/tap.c
>> index 26084b486519..ec3a0d68ea2f 100644
>> --- a/tap.c
>> +++ b/tap.c
>> @@ -921,6 +921,60 @@ append:
>> return in->count;
>> }
>>
>> +/**
>> + * pool_flush() - Flush both IPv4 and IPv6 packet pools
>> + */
>> +void tap_flush_pools(void)
>> +{
>> + pool_flush(pool_tap4);
>> + pool_flush(pool_tap6);
>> +}
>> +
>> +/**
>> + * tap_handler() - IPv4/IPv6 and ARP packet handler for tap file descriptor
>> + * @c: Execution context
>> + * @now: Current timestamp
>> + */
>> +void tap_handler(struct ctx *c, const struct timespec *now)
>> +{
>> + tap4_handler(c, pool_tap4, now);
>> + tap6_handler(c, pool_tap6, now);
>> +}
>> +
>> +/**
>> + * tap_add_packet() - Queue/capture packet, update notion of guest MAC address
>> + * @c: Execution context
>> + * @l2len: Total L2 packet length
>> + * @p: Packet buffer
>> + * @func: For tracing: name of calling function, NULL means no trace()
>> + * @line: For tracing: caller line of function call
>> + */
>> +void tap_add_packet(struct ctx *c, ssize_t l2len, char *p)
>> +{
>> + const struct ethhdr *eh;
>> +
>> + pcap(p, l2len);
>> +
>> + eh = (struct ethhdr *)p;
>> +
>> + if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
>> + memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
>> + proto_update_l2_buf(c->mac_guest, NULL);
>> + }
>> +
>> + switch (ntohs(eh->h_proto)) {
>> + case ETH_P_ARP:
>> + case ETH_P_IP:
>> + packet_add(pool_tap4, l2len, p);
>> + break;
>> + case ETH_P_IPV6:
>> + packet_add(pool_tap6, l2len, p);
>> + break;
>> + default:
>> + break;
>> + }
>> +}
>> +
>> /**
>> * tap_sock_reset() - Handle closing or failure of connect AF_UNIX socket
>> * @c: Execution context
>> @@ -947,7 +1001,6 @@ static void tap_sock_reset(struct ctx *c)
>> void tap_handler_passt(struct ctx *c, uint32_t events,
>> const struct timespec *now)
>> {
>> - const struct ethhdr *eh;
>> ssize_t n, rem;
>> char *p;
>>
>> @@ -960,8 +1013,7 @@ redo:
>> p = pkt_buf;
>> rem = 0;
>>
>> - pool_flush(pool_tap4);
>> - pool_flush(pool_tap6);
>> + tap_flush_pools();
>>
>> n = recv(c->fd_tap, p, TAP_BUF_FILL, MSG_DONTWAIT);
>> if (n < 0) {
>> @@ -988,38 +1040,18 @@ redo:
>> /* Complete the partial read above before discarding a malformed
>> * frame, otherwise the stream will be inconsistent.
>> */
>> - if (l2len < (ssize_t)sizeof(*eh) ||
>> + if (l2len < (ssize_t)sizeof(struct ethhdr) ||
>> l2len > (ssize_t)ETH_MAX_MTU)
>> goto next;
>>
>> - pcap(p, l2len);
>> -
>> - eh = (struct ethhdr *)p;
>> -
>> - if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
>> - memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
>> - proto_update_l2_buf(c->mac_guest, NULL);
>> - }
>> -
>> - switch (ntohs(eh->h_proto)) {
>> - case ETH_P_ARP:
>> - case ETH_P_IP:
>> - packet_add(pool_tap4, l2len, p);
>> - break;
>> - case ETH_P_IPV6:
>> - packet_add(pool_tap6, l2len, p);
>> - break;
>> - default:
>> - break;
>> - }
>> + tap_add_packet(c, l2len, p);
>>
>> next:
>> p += l2len;
>> n -= l2len;
>> }
>>
>> - tap4_handler(c, pool_tap4, now);
>> - tap6_handler(c, pool_tap6, now);
>> + tap_handler(c, now);
>>
>> /* We can't use EPOLLET otherwise. */
>> if (rem)
>> @@ -1044,35 +1076,18 @@ void tap_handler_pasta(struct ctx *c, uint32_t events,
>> redo:
>> n = 0;
>>
>> - pool_flush(pool_tap4);
>> - pool_flush(pool_tap6);
>> + tap_flush_pools();
>> restart:
>> while ((len = read(c->fd_tap, pkt_buf + n, TAP_BUF_BYTES - n)) > 0) {
>> - const struct ethhdr *eh = (struct ethhdr *)(pkt_buf + n);
>>
>> - if (len < (ssize_t)sizeof(*eh) || len > (ssize_t)ETH_MAX_MTU) {
>> + if (len < (ssize_t)sizeof(struct ethhdr) ||
>> + len > (ssize_t)ETH_MAX_MTU) {
>> n += len;
>> continue;
>> }
>>
>> - pcap(pkt_buf + n, len);
>>
>> - if (memcmp(c->mac_guest, eh->h_source, ETH_ALEN)) {
>> - memcpy(c->mac_guest, eh->h_source, ETH_ALEN);
>> - proto_update_l2_buf(c->mac_guest, NULL);
>> - }
>> -
>> - switch (ntohs(eh->h_proto)) {
>> - case ETH_P_ARP:
>> - case ETH_P_IP:
>> - packet_add(pool_tap4, len, pkt_buf + n);
>> - break;
>> - case ETH_P_IPV6:
>> - packet_add(pool_tap6, len, pkt_buf + n);
>> - break;
>> - default:
>> - break;
>> - }
>> + tap_add_packet(c, len, pkt_buf + n);
>>
>> if ((n += len) == TAP_BUF_BYTES)
>> break;
>> @@ -1083,8 +1098,7 @@ restart:
>>
>> ret = errno;
>>
>> - tap4_handler(c, pool_tap4, now);
>> - tap6_handler(c, pool_tap6, now);
>> + tap_handler(c, now);
>>
>> if (len > 0 || ret == EAGAIN)
>> return;
>> diff --git a/tap.h b/tap.h
>> index 2285a87093f9..d496bd0e4b99 100644
>> --- a/tap.h
>> +++ b/tap.h
>> @@ -70,5 +70,8 @@ void tap_handler_passt(struct ctx *c, uint32_t events,
>> const struct timespec *now);
>> int tap_sock_unix_open(char *sock_path);
>> void tap_sock_init(struct ctx *c);
>> +void tap_flush_pools(void);
>> +void tap_handler(struct ctx *c, const struct timespec *now);
>> +void tap_add_packet(struct ctx *c, ssize_t l2len, char *p);
>>
>> #endif /* TAP_H */
>
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH v6 4/8] udp: refactor UDP header update functions
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (2 preceding siblings ...)
2024-06-12 15:47 ` [PATCH v6 3/8] tap: refactor packets handling functions Laurent Vivier
@ 2024-06-12 15:47 ` Laurent Vivier
2024-06-12 15:47 ` [PATCH v6 5/8] udp: rename udp_sock_handler() to udp_buf_sock_handler() Laurent Vivier
` (4 subsequent siblings)
8 siblings, 0 replies; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 15:47 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier, David Gibson
This commit refactors the udp_update_hdr4() and udp_update_hdr6() functions
to improve code portability by replacing the udp_meta_t parameter with
more specific parameters for the IPv4 and IPv6 headers (iphdr/ipv6hdr)
and the source socket address (sockaddr_in/sockaddr_in6).
It also moves the tap_hdr_update() function call inside the udp_tap_send()
function not to have to pass the TAP header to udp_update_hdr4() and
udp_update_hdr6()
This refactor reduces complexity by making the functions more modular and
ensuring that each function operates on more narrowly scoped data structures.
This will facilitate future backend introduction like vhost-user.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
Notes:
v6:
- reorder declarations, align summing
v2:
- move taph out of udp_update_hdr4()/udp_update_hdr6()
udp.c | 60 +++++++++++++++++++++++++++++++++--------------------------
1 file changed, 34 insertions(+), 26 deletions(-)
diff --git a/udp.c b/udp.c
index 61e106a9f05e..5bef1af969cc 100644
--- a/udp.c
+++ b/udp.c
@@ -555,7 +555,8 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
/**
* udp_update_hdr4() - Update headers for one IPv4 datagram
* @c: Execution context
- * @bm: Pointer to udp_meta_t to update
+ * @ip4h: Pre-filled IPv4 header (except for tot_len and saddr)
+ * @s_in: Source socket address, filled in by recvmmsg()
* @bp: Pointer to udp_payload_t to update
* @dstport: Destination port number
* @dlen: Length of UDP payload
@@ -564,15 +565,16 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
* Return: size of IPv4 payload (UDP header + data)
*/
static size_t udp_update_hdr4(const struct ctx *c,
- struct udp_meta_t *bm, struct udp_payload_t *bp,
+ struct iphdr *ip4h, const struct sockaddr_in *s_in,
+ struct udp_payload_t *bp,
in_port_t dstport, size_t dlen,
const struct timespec *now)
{
- in_port_t srcport = ntohs(bm->s_in.sa4.sin_port);
const struct in_addr dst = c->ip4.addr_seen;
- struct in_addr src = bm->s_in.sa4.sin_addr;
+ in_port_t srcport = ntohs(s_in->sin_port);
size_t l4len = dlen + sizeof(bp->uh);
- size_t l3len = l4len + sizeof(bm->ip4h);
+ size_t l3len = l4len + sizeof(*ip4h);
+ struct in_addr src = s_in->sin_addr;
if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) &&
IN4_ARE_ADDR_EQUAL(&src, &c->ip4.dns_host) && srcport == 53 &&
@@ -593,24 +595,24 @@ static size_t udp_update_hdr4(const struct ctx *c,
src = c->ip4.gw;
}
- bm->ip4h.tot_len = htons(l3len);
- bm->ip4h.daddr = dst.s_addr;
- bm->ip4h.saddr = src.s_addr;
- bm->ip4h.check = csum_ip4_header(l3len, IPPROTO_UDP, src, dst);
+ ip4h->tot_len = htons(l3len);
+ ip4h->daddr = dst.s_addr;
+ ip4h->saddr = src.s_addr;
+ ip4h->check = csum_ip4_header(l3len, IPPROTO_UDP, src, dst);
- bp->uh.source = bm->s_in.sa4.sin_port;
+ bp->uh.source = s_in->sin_port;
bp->uh.dest = htons(dstport);
bp->uh.len = htons(l4len);
csum_udp4(&bp->uh, src, dst, bp->data, dlen);
- tap_hdr_update(&bm->taph, l3len + sizeof(udp4_eth_hdr));
return l4len;
}
/**
* udp_update_hdr6() - Update headers for one IPv6 datagram
* @c: Execution context
- * @bm: Pointer to udp_meta_t to update
+ * @ip6h: Pre-filled IPv6 header (except for payload_len and addresses)
+ * @s_in: Source socket address, filled in by recvmmsg()
* @bp: Pointer to udp_payload_t to update
* @dstport: Destination port number
* @dlen: Length of UDP payload
@@ -619,13 +621,14 @@ static size_t udp_update_hdr4(const struct ctx *c,
* Return: size of IPv6 payload (UDP header + data)
*/
static size_t udp_update_hdr6(const struct ctx *c,
- struct udp_meta_t *bm, struct udp_payload_t *bp,
+ struct ipv6hdr *ip6h, struct sockaddr_in6 *s_in6,
+ struct udp_payload_t *bp,
in_port_t dstport, size_t dlen,
const struct timespec *now)
{
- const struct in6_addr *src = &bm->s_in.sa6.sin6_addr;
+ const struct in6_addr *src = &s_in6->sin6_addr;
const struct in6_addr *dst = &c->ip6.addr_seen;
- in_port_t srcport = ntohs(bm->s_in.sa6.sin6_port);
+ in_port_t srcport = ntohs(s_in6->sin6_port);
uint16_t l4len = dlen + sizeof(bp->uh);
if (IN6_IS_ADDR_LINKLOCAL(src)) {
@@ -662,19 +665,18 @@ static size_t udp_update_hdr6(const struct ctx *c,
}
- bm->ip6h.payload_len = htons(l4len);
- bm->ip6h.daddr = *dst;
- bm->ip6h.saddr = *src;
- bm->ip6h.version = 6;
- bm->ip6h.nexthdr = IPPROTO_UDP;
- bm->ip6h.hop_limit = 255;
+ ip6h->payload_len = htons(l4len);
+ ip6h->daddr = *dst;
+ ip6h->saddr = *src;
+ ip6h->version = 6;
+ ip6h->nexthdr = IPPROTO_UDP;
+ ip6h->hop_limit = 255;
- bp->uh.source = bm->s_in.sa6.sin6_port;
+ bp->uh.source = s_in6->sin6_port;
bp->uh.dest = htons(dstport);
- bp->uh.len = bm->ip6h.payload_len;
+ bp->uh.len = ip6h->payload_len;
csum_udp6(&bp->uh, src, dst, bp->data, dlen);
- tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip6h) + sizeof(udp6_eth_hdr));
return l4len;
}
@@ -707,11 +709,17 @@ static void udp_tap_send(const struct ctx *c,
size_t l4len;
if (v6) {
- l4len = udp_update_hdr6(c, bm, bp, dstport,
+ l4len = udp_update_hdr6(c, &bm->ip6h,
+ &bm->s_in.sa6, bp, dstport,
udp6_l2_mh_sock[i].msg_len, now);
+ tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip6h) +
+ sizeof(udp6_eth_hdr));
} else {
- l4len = udp_update_hdr4(c, bm, bp, dstport,
+ l4len = udp_update_hdr4(c, &bm->ip4h,
+ &bm->s_in.sa4, bp, dstport,
udp4_l2_mh_sock[i].msg_len, now);
+ tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip4h) +
+ sizeof(udp4_eth_hdr));
}
tap_iov[i][UDP_IOV_PAYLOAD].iov_len = l4len;
}
--
@@ -555,7 +555,8 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
/**
* udp_update_hdr4() - Update headers for one IPv4 datagram
* @c: Execution context
- * @bm: Pointer to udp_meta_t to update
+ * @ip4h: Pre-filled IPv4 header (except for tot_len and saddr)
+ * @s_in: Source socket address, filled in by recvmmsg()
* @bp: Pointer to udp_payload_t to update
* @dstport: Destination port number
* @dlen: Length of UDP payload
@@ -564,15 +565,16 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
* Return: size of IPv4 payload (UDP header + data)
*/
static size_t udp_update_hdr4(const struct ctx *c,
- struct udp_meta_t *bm, struct udp_payload_t *bp,
+ struct iphdr *ip4h, const struct sockaddr_in *s_in,
+ struct udp_payload_t *bp,
in_port_t dstport, size_t dlen,
const struct timespec *now)
{
- in_port_t srcport = ntohs(bm->s_in.sa4.sin_port);
const struct in_addr dst = c->ip4.addr_seen;
- struct in_addr src = bm->s_in.sa4.sin_addr;
+ in_port_t srcport = ntohs(s_in->sin_port);
size_t l4len = dlen + sizeof(bp->uh);
- size_t l3len = l4len + sizeof(bm->ip4h);
+ size_t l3len = l4len + sizeof(*ip4h);
+ struct in_addr src = s_in->sin_addr;
if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) &&
IN4_ARE_ADDR_EQUAL(&src, &c->ip4.dns_host) && srcport == 53 &&
@@ -593,24 +595,24 @@ static size_t udp_update_hdr4(const struct ctx *c,
src = c->ip4.gw;
}
- bm->ip4h.tot_len = htons(l3len);
- bm->ip4h.daddr = dst.s_addr;
- bm->ip4h.saddr = src.s_addr;
- bm->ip4h.check = csum_ip4_header(l3len, IPPROTO_UDP, src, dst);
+ ip4h->tot_len = htons(l3len);
+ ip4h->daddr = dst.s_addr;
+ ip4h->saddr = src.s_addr;
+ ip4h->check = csum_ip4_header(l3len, IPPROTO_UDP, src, dst);
- bp->uh.source = bm->s_in.sa4.sin_port;
+ bp->uh.source = s_in->sin_port;
bp->uh.dest = htons(dstport);
bp->uh.len = htons(l4len);
csum_udp4(&bp->uh, src, dst, bp->data, dlen);
- tap_hdr_update(&bm->taph, l3len + sizeof(udp4_eth_hdr));
return l4len;
}
/**
* udp_update_hdr6() - Update headers for one IPv6 datagram
* @c: Execution context
- * @bm: Pointer to udp_meta_t to update
+ * @ip6h: Pre-filled IPv6 header (except for payload_len and addresses)
+ * @s_in: Source socket address, filled in by recvmmsg()
* @bp: Pointer to udp_payload_t to update
* @dstport: Destination port number
* @dlen: Length of UDP payload
@@ -619,13 +621,14 @@ static size_t udp_update_hdr4(const struct ctx *c,
* Return: size of IPv6 payload (UDP header + data)
*/
static size_t udp_update_hdr6(const struct ctx *c,
- struct udp_meta_t *bm, struct udp_payload_t *bp,
+ struct ipv6hdr *ip6h, struct sockaddr_in6 *s_in6,
+ struct udp_payload_t *bp,
in_port_t dstport, size_t dlen,
const struct timespec *now)
{
- const struct in6_addr *src = &bm->s_in.sa6.sin6_addr;
+ const struct in6_addr *src = &s_in6->sin6_addr;
const struct in6_addr *dst = &c->ip6.addr_seen;
- in_port_t srcport = ntohs(bm->s_in.sa6.sin6_port);
+ in_port_t srcport = ntohs(s_in6->sin6_port);
uint16_t l4len = dlen + sizeof(bp->uh);
if (IN6_IS_ADDR_LINKLOCAL(src)) {
@@ -662,19 +665,18 @@ static size_t udp_update_hdr6(const struct ctx *c,
}
- bm->ip6h.payload_len = htons(l4len);
- bm->ip6h.daddr = *dst;
- bm->ip6h.saddr = *src;
- bm->ip6h.version = 6;
- bm->ip6h.nexthdr = IPPROTO_UDP;
- bm->ip6h.hop_limit = 255;
+ ip6h->payload_len = htons(l4len);
+ ip6h->daddr = *dst;
+ ip6h->saddr = *src;
+ ip6h->version = 6;
+ ip6h->nexthdr = IPPROTO_UDP;
+ ip6h->hop_limit = 255;
- bp->uh.source = bm->s_in.sa6.sin6_port;
+ bp->uh.source = s_in6->sin6_port;
bp->uh.dest = htons(dstport);
- bp->uh.len = bm->ip6h.payload_len;
+ bp->uh.len = ip6h->payload_len;
csum_udp6(&bp->uh, src, dst, bp->data, dlen);
- tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip6h) + sizeof(udp6_eth_hdr));
return l4len;
}
@@ -707,11 +709,17 @@ static void udp_tap_send(const struct ctx *c,
size_t l4len;
if (v6) {
- l4len = udp_update_hdr6(c, bm, bp, dstport,
+ l4len = udp_update_hdr6(c, &bm->ip6h,
+ &bm->s_in.sa6, bp, dstport,
udp6_l2_mh_sock[i].msg_len, now);
+ tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip6h) +
+ sizeof(udp6_eth_hdr));
} else {
- l4len = udp_update_hdr4(c, bm, bp, dstport,
+ l4len = udp_update_hdr4(c, &bm->ip4h,
+ &bm->s_in.sa4, bp, dstport,
udp4_l2_mh_sock[i].msg_len, now);
+ tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip4h) +
+ sizeof(udp4_eth_hdr));
}
tap_iov[i][UDP_IOV_PAYLOAD].iov_len = l4len;
}
--
2.45.2
^ permalink raw reply related [flat|nested] 25+ messages in thread* [PATCH v6 5/8] udp: rename udp_sock_handler() to udp_buf_sock_handler()
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (3 preceding siblings ...)
2024-06-12 15:47 ` [PATCH v6 4/8] udp: refactor UDP header update functions Laurent Vivier
@ 2024-06-12 15:47 ` Laurent Vivier
2024-06-12 15:47 ` [PATCH v6 6/8] vhost-user: compare mode MODE_PASTA and not MODE_PASST Laurent Vivier
` (3 subsequent siblings)
8 siblings, 0 replies; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 15:47 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier, David Gibson
We are going to introduce a variant of the function to use
vhost-user buffers rather than passt internal buffers.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
passt.c | 2 +-
udp.c | 6 +++---
udp.h | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/passt.c b/passt.c
index dabd86ed8fbd..e747225d9a7c 100644
--- a/passt.c
+++ b/passt.c
@@ -365,7 +365,7 @@ loop:
tcp_timer_handler(&c, ref);
break;
case EPOLL_TYPE_UDP:
- udp_sock_handler(&c, ref, eventmask, &now);
+ udp_buf_sock_handler(&c, ref, eventmask, &now);
break;
case EPOLL_TYPE_PING:
icmp_sock_handler(&c, ref);
diff --git a/udp.c b/udp.c
index 5bef1af969cc..225846758924 100644
--- a/udp.c
+++ b/udp.c
@@ -728,7 +728,7 @@ static void udp_tap_send(const struct ctx *c,
}
/**
- * udp_sock_handler() - Handle new data from socket
+ * udp_buf_sock_handler() - Handle new data from socket
* @c: Execution context
* @ref: epoll reference
* @events: epoll events bitmap
@@ -736,8 +736,8 @@ static void udp_tap_send(const struct ctx *c,
*
* #syscalls recvmmsg
*/
-void udp_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
- const struct timespec *now)
+void udp_buf_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
+ const struct timespec *now)
{
/* For not entirely clear reasons (data locality?) pasta gets
* better throughput if we receive tap datagrams one at a
diff --git a/udp.h b/udp.h
index 9976b6231f1c..5865def20856 100644
--- a/udp.h
+++ b/udp.h
@@ -9,7 +9,7 @@
#define UDP_TIMER_INTERVAL 1000 /* ms */
void udp_portmap_clear(void);
-void udp_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
+void udp_buf_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
const struct timespec *now);
int udp_tap_handler(struct ctx *c, uint8_t pif, sa_family_t af,
const void *saddr, const void *daddr,
--
@@ -9,7 +9,7 @@
#define UDP_TIMER_INTERVAL 1000 /* ms */
void udp_portmap_clear(void);
-void udp_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
+void udp_buf_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
const struct timespec *now);
int udp_tap_handler(struct ctx *c, uint8_t pif, sa_family_t af,
const void *saddr, const void *daddr,
--
2.45.2
^ permalink raw reply related [flat|nested] 25+ messages in thread* [PATCH v6 6/8] vhost-user: compare mode MODE_PASTA and not MODE_PASST
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (4 preceding siblings ...)
2024-06-12 15:47 ` [PATCH v6 5/8] udp: rename udp_sock_handler() to udp_buf_sock_handler() Laurent Vivier
@ 2024-06-12 15:47 ` Laurent Vivier
2024-06-12 15:47 ` [PATCH v6 7/8] iov: remove iov_copy() Laurent Vivier
` (2 subsequent siblings)
8 siblings, 0 replies; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 15:47 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier, David Gibson
As we are going to introduce the MODE_VU that will act like
the mode MODE_PASST, compare to MODE_PASTA rather than to add
a comparison to MODE_VU when we check for MODE_PASST.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
Notes:
v6:
- add curly brackets
v2:
- compare to MODE_PASTA in conf_open_files() too
conf.c | 14 +++++++-------
isolation.c | 10 +++++-----
passt.c | 2 +-
tap.c | 12 ++++++------
tcp_buf.c | 2 +-
udp.c | 2 +-
6 files changed, 21 insertions(+), 21 deletions(-)
diff --git a/conf.c b/conf.c
index 3998bfaa69e9..94b3ed6fa659 100644
--- a/conf.c
+++ b/conf.c
@@ -147,7 +147,7 @@ static void conf_ports(const struct ctx *c, char optname, const char *optarg,
if (fwd->mode)
goto mode_conflict;
- if (c->mode != MODE_PASST)
+ if (c->mode == MODE_PASTA)
die("'all' port forwarding is only allowed for passt");
fwd->mode = FWD_ALL;
@@ -1118,7 +1118,7 @@ static void conf_ugid(char *runas, uid_t *uid, gid_t *gid)
*/
static void conf_open_files(struct ctx *c)
{
- if (c->mode == MODE_PASST && c->fd_tap == -1)
+ if (c->mode != MODE_PASTA && c->fd_tap == -1)
c->fd_tap_listen = tap_sock_unix_open(c->sock_path);
c->pidfile_fd = pidfile_open(c->pidfile);
@@ -1285,7 +1285,7 @@ void conf(struct ctx *c, int argc, char **argv)
c->no_dhcp_dns = 0;
break;
case 6:
- if (c->mode != MODE_PASST)
+ if (c->mode == MODE_PASTA)
die("--no-dhcp-dns is for passt mode only");
c->no_dhcp_dns = 1;
@@ -1297,7 +1297,7 @@ void conf(struct ctx *c, int argc, char **argv)
c->no_dhcp_dns_search = 0;
break;
case 8:
- if (c->mode != MODE_PASST)
+ if (c->mode == MODE_PASTA)
die("--no-dhcp-search is for passt mode only");
c->no_dhcp_dns_search = 1;
@@ -1352,7 +1352,7 @@ void conf(struct ctx *c, int argc, char **argv)
break;
case 14:
fprintf(stdout,
- c->mode == MODE_PASST ? "passt " : "pasta ");
+ c->mode == MODE_PASTA ? "pasta " : "passt ");
fprintf(stdout, VERSION_BLOB);
exit(EXIT_SUCCESS);
case 15:
@@ -1648,7 +1648,7 @@ void conf(struct ctx *c, int argc, char **argv)
v6_only = true;
break;
case '1':
- if (c->mode != MODE_PASST)
+ if (c->mode == MODE_PASTA)
die("--one-off is for passt mode only");
if (c->one_off)
@@ -1694,7 +1694,7 @@ void conf(struct ctx *c, int argc, char **argv)
conf_ugid(runas, &uid, &gid);
if (logfile) {
- logfile_init(c->mode == MODE_PASST ? "passt" : "pasta",
+ logfile_init(c->mode == MODE_PASTA ? "pasta" : "passt",
logfile, logsize);
}
diff --git a/isolation.c b/isolation.c
index f394e93b8526..ca2c68b52ec7 100644
--- a/isolation.c
+++ b/isolation.c
@@ -312,7 +312,7 @@ int isolate_prefork(const struct ctx *c)
* PID namespace. For passt, use CLONE_NEWPID anyway, in case somebody
* ever gets around seccomp profiles -- there's no harm in passing it.
*/
- if (!c->foreground || c->mode == MODE_PASST)
+ if (!c->foreground || c->mode != MODE_PASTA)
flags |= CLONE_NEWPID;
if (unshare(flags)) {
@@ -379,12 +379,12 @@ void isolate_postfork(const struct ctx *c)
prctl(PR_SET_DUMPABLE, 0);
- if (c->mode == MODE_PASST) {
- prog.len = (unsigned short)ARRAY_SIZE(filter_passt);
- prog.filter = filter_passt;
- } else {
+ if (c->mode == MODE_PASTA) {
prog.len = (unsigned short)ARRAY_SIZE(filter_pasta);
prog.filter = filter_pasta;
+ } else {
+ prog.len = (unsigned short)ARRAY_SIZE(filter_passt);
+ prog.filter = filter_passt;
}
if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) ||
diff --git a/passt.c b/passt.c
index e747225d9a7c..a5e2c5a8e151 100644
--- a/passt.c
+++ b/passt.c
@@ -333,7 +333,7 @@ loop:
uint32_t eventmask = events[i].events;
trace("%s: epoll event on %s %i (events: 0x%08x)",
- c.mode == MODE_PASST ? "passt" : "pasta",
+ c.mode == MODE_PASTA ? "pasta" : "passt",
EPOLL_TYPE_STR(ref.type), ref.fd, eventmask);
switch (ref.type) {
diff --git a/tap.c b/tap.c
index ec3a0d68ea2f..4f7da7645599 100644
--- a/tap.c
+++ b/tap.c
@@ -416,10 +416,10 @@ size_t tap_send_frames(const struct ctx *c, const struct iovec *iov,
if (!nframes)
return 0;
- if (c->mode == MODE_PASST)
- m = tap_send_frames_passt(c, iov, bufs_per_frame, nframes);
- else
+ if (c->mode == MODE_PASTA)
m = tap_send_frames_pasta(c, iov, bufs_per_frame, nframes);
+ else
+ m = tap_send_frames_passt(c, iov, bufs_per_frame, nframes);
if (m < nframes)
debug("tap: failed to send %zu frames of %zu",
@@ -1332,7 +1332,9 @@ void tap_sock_init(struct ctx *c)
return;
}
- if (c->mode == MODE_PASST) {
+ if (c->mode == MODE_PASTA) {
+ tap_sock_tun_init(c);
+ } else {
tap_sock_unix_init(c);
/* In passt mode, we don't know the guest's MAC address until it
@@ -1340,7 +1342,5 @@ void tap_sock_init(struct ctx *c)
* first packets will reach it.
*/
memset(&c->mac_guest, 0xff, sizeof(c->mac_guest));
- } else {
- tap_sock_tun_init(c);
}
}
diff --git a/tcp_buf.c b/tcp_buf.c
index 0c7d07b8d0bd..fd7843880f84 100644
--- a/tcp_buf.c
+++ b/tcp_buf.c
@@ -35,7 +35,7 @@
#define TCP_FRAMES_MEM 128
#define TCP_FRAMES \
- (c->mode == MODE_PASST ? TCP_FRAMES_MEM : 1)
+ (c->mode == MODE_PASTA ? 1 : TCP_FRAMES_MEM)
/* Static buffers */
/**
diff --git a/udp.c b/udp.c
index 225846758924..dba75d7fecbd 100644
--- a/udp.c
+++ b/udp.c
@@ -747,7 +747,7 @@ void udp_buf_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t eve
* whether we'll use tap or splice, always go one at a time
* for pasta mode.
*/
- ssize_t n = (c->mode == MODE_PASST ? UDP_MAX_FRAMES : 1);
+ ssize_t n = (c->mode == MODE_PASTA ? 1 : UDP_MAX_FRAMES);
in_port_t dstport = ref.udp.port;
bool v6 = ref.udp.v6;
struct mmsghdr *mmh_recv;
--
@@ -747,7 +747,7 @@ void udp_buf_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t eve
* whether we'll use tap or splice, always go one at a time
* for pasta mode.
*/
- ssize_t n = (c->mode == MODE_PASST ? UDP_MAX_FRAMES : 1);
+ ssize_t n = (c->mode == MODE_PASTA ? 1 : UDP_MAX_FRAMES);
in_port_t dstport = ref.udp.port;
bool v6 = ref.udp.v6;
struct mmsghdr *mmh_recv;
--
2.45.2
^ permalink raw reply related [flat|nested] 25+ messages in thread* [PATCH v6 7/8] iov: remove iov_copy()
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (5 preceding siblings ...)
2024-06-12 15:47 ` [PATCH v6 6/8] vhost-user: compare mode MODE_PASTA and not MODE_PASST Laurent Vivier
@ 2024-06-12 15:47 ` Laurent Vivier
2024-06-12 15:47 ` [PATCH v6 8/8] tap: use in->buf_size rather than sizeof(pkt_buf) Laurent Vivier
2024-06-12 17:16 ` [PATCH v6 0/8] Add vhost-user support to passt (part 2) Stefano Brivio
8 siblings, 0 replies; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 15:47 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier, David Gibson
it was needed by a draft version of vhost-user, it is not needed
anymore.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
iov.c | 39 ---------------------------------------
iov.h | 3 ---
2 files changed, 42 deletions(-)
diff --git a/iov.c b/iov.c
index 52a7c014a171..3f9e229a305f 100644
--- a/iov.c
+++ b/iov.c
@@ -156,42 +156,3 @@ size_t iov_size(const struct iovec *iov, size_t iov_cnt)
return len;
}
-
-/**
- * iov_copy - Copy data from one scatter/gather I/O vector (struct iovec) to
- * another.
- *
- * @dst_iov: Pointer to the destination array of struct iovec describing
- * the scatter/gather I/O vector to copy to.
- * @dst_iov_cnt: Number of elements in the destination iov array.
- * @iov: Pointer to the source array of struct iovec describing
- * the scatter/gather I/O vector to copy from.
- * @iov_cnt: Number of elements in the source iov array.
- * @offset: Offset within the source iov from where copying should start.
- * @bytes: Total number of bytes to copy from iov to dst_iov.
- *
- * Returns: The number of elements successfully copied to the destination
- * iov array.
- */
-/* cppcheck-suppress unusedFunction */
-unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
- const struct iovec *iov, size_t iov_cnt,
- size_t offset, size_t bytes)
-{
- unsigned int i, j;
-
- i = iov_skip_bytes(iov, iov_cnt, offset, &offset);
-
- /* copying data */
- for (j = 0; i < iov_cnt && j < dst_iov_cnt && bytes; i++) {
- size_t len = MIN(bytes, iov[i].iov_len - offset);
-
- dst_iov[j].iov_base = (char *)iov[i].iov_base + offset;
- dst_iov[j].iov_len = len;
- j++;
- bytes -= len;
- offset = 0;
- }
-
- return j;
-}
diff --git a/iov.h b/iov.h
index 5668ca5f93bc..a9e1722713b3 100644
--- a/iov.h
+++ b/iov.h
@@ -28,7 +28,4 @@ size_t iov_from_buf(const struct iovec *iov, size_t iov_cnt,
size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
size_t offset, void *buf, size_t bytes);
size_t iov_size(const struct iovec *iov, size_t iov_cnt);
-unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
- const struct iovec *iov, size_t iov_cnt,
- size_t offset, size_t bytes);
#endif /* IOVEC_H */
--
@@ -28,7 +28,4 @@ size_t iov_from_buf(const struct iovec *iov, size_t iov_cnt,
size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
size_t offset, void *buf, size_t bytes);
size_t iov_size(const struct iovec *iov, size_t iov_cnt);
-unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
- const struct iovec *iov, size_t iov_cnt,
- size_t offset, size_t bytes);
#endif /* IOVEC_H */
--
2.45.2
^ permalink raw reply related [flat|nested] 25+ messages in thread* [PATCH v6 8/8] tap: use in->buf_size rather than sizeof(pkt_buf)
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (6 preceding siblings ...)
2024-06-12 15:47 ` [PATCH v6 7/8] iov: remove iov_copy() Laurent Vivier
@ 2024-06-12 15:47 ` Laurent Vivier
2024-06-12 17:16 ` [PATCH v6 0/8] Add vhost-user support to passt (part 2) Stefano Brivio
8 siblings, 0 replies; 25+ messages in thread
From: Laurent Vivier @ 2024-06-12 15:47 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier, David Gibson
buf_size is set to sizeof(pkt_buf) by default. And it seems more correct
to provide the actual size of the buffer.
Later a buf_size of 0 will allow vhost-user mode to detect
guest memory buffers.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
tap.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/tap.c b/tap.c
index 4f7da7645599..856708979371 100644
--- a/tap.c
+++ b/tap.c
@@ -602,7 +602,7 @@ resume:
if (!eh)
continue;
if (ntohs(eh->h_proto) == ETH_P_ARP) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
packet_add(pkt, l2len, (char *)eh);
arp(c, pkt);
@@ -642,7 +642,7 @@ resume:
continue;
if (iph->protocol == IPPROTO_ICMP) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
if (c->no_icmp)
continue;
@@ -661,7 +661,7 @@ resume:
continue;
if (iph->protocol == IPPROTO_UDP) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
packet_add(pkt, l2len, (char *)eh);
if (dhcp(c, pkt))
@@ -810,7 +810,7 @@ resume:
}
if (proto == IPPROTO_ICMPV6) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
if (c->no_icmp)
continue;
@@ -834,7 +834,7 @@ resume:
uh = (struct udphdr *)l4h;
if (proto == IPPROTO_UDP) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
packet_add(pkt, l4len, l4h);
--
@@ -602,7 +602,7 @@ resume:
if (!eh)
continue;
if (ntohs(eh->h_proto) == ETH_P_ARP) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
packet_add(pkt, l2len, (char *)eh);
arp(c, pkt);
@@ -642,7 +642,7 @@ resume:
continue;
if (iph->protocol == IPPROTO_ICMP) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
if (c->no_icmp)
continue;
@@ -661,7 +661,7 @@ resume:
continue;
if (iph->protocol == IPPROTO_UDP) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
packet_add(pkt, l2len, (char *)eh);
if (dhcp(c, pkt))
@@ -810,7 +810,7 @@ resume:
}
if (proto == IPPROTO_ICMPV6) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
if (c->no_icmp)
continue;
@@ -834,7 +834,7 @@ resume:
uh = (struct udphdr *)l4h;
if (proto == IPPROTO_UDP) {
- PACKET_POOL_P(pkt, 1, in->buf, sizeof(pkt_buf));
+ PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
packet_add(pkt, l4len, l4h);
--
2.45.2
^ permalink raw reply related [flat|nested] 25+ messages in thread* Re: [PATCH v6 0/8] Add vhost-user support to passt (part 2)
2024-06-12 15:47 [PATCH v6 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (7 preceding siblings ...)
2024-06-12 15:47 ` [PATCH v6 8/8] tap: use in->buf_size rather than sizeof(pkt_buf) Laurent Vivier
@ 2024-06-12 17:16 ` Stefano Brivio
2024-06-12 17:37 ` Stefano Brivio
8 siblings, 1 reply; 25+ messages in thread
From: Stefano Brivio @ 2024-06-12 17:16 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
On Wed, 12 Jun 2024 17:47:26 +0200
Laurent Vivier <lvivier@redhat.com> wrote:
> Extract buffers management code from tcp.c and move
> it to tcp_buf.c
> tcp.c keeps all the generic code and will be also used by
> the vhost-user functions.
>
> Also compare mode to MODE_PASTA, as we will manage vhost-user
> mode (MODE_VU) like MODE_PASST.
Something in this series breaks the pasta_podman/bats test, number 19
in that script (Single TCP port forwarding, IPv4, tap). I'm bisecting
now...
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 0/8] Add vhost-user support to passt (part 2)
2024-06-12 17:16 ` [PATCH v6 0/8] Add vhost-user support to passt (part 2) Stefano Brivio
@ 2024-06-12 17:37 ` Stefano Brivio
2024-06-12 21:23 ` Stefano Brivio
0 siblings, 1 reply; 25+ messages in thread
From: Stefano Brivio @ 2024-06-12 17:37 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
On Wed, 12 Jun 2024 19:16:17 +0200
Stefano Brivio <sbrivio@redhat.com> wrote:
> On Wed, 12 Jun 2024 17:47:26 +0200
> Laurent Vivier <lvivier@redhat.com> wrote:
>
> > Extract buffers management code from tcp.c and move
> > it to tcp_buf.c
> > tcp.c keeps all the generic code and will be also used by
> > the vhost-user functions.
> >
> > Also compare mode to MODE_PASTA, as we will manage vhost-user
> > mode (MODE_VU) like MODE_PASST.
>
> Something in this series breaks the pasta_podman/bats test, number 19
> in that script (Single TCP port forwarding, IPv4, tap). I'm bisecting
> now...
$ git bisect good
3c6a20486425ed00ba5b631bea11135045794dc2 is the first bad commit
commit 3c6a20486425ed00ba5b631bea11135045794dc2
Author: Laurent Vivier <lvivier@redhat.com>
Date: Wed Jun 12 17:47:34 2024 +0200
tap: use in->buf_size rather than sizeof(pkt_buf)
buf_size is set to sizeof(pkt_buf) by default. And it seems more correct
to provide the actual size of the buffer.
Later a buf_size of 0 will allow vhost-user mode to detect
guest memory buffers.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
tap.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
...checking that patch now.
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v6 0/8] Add vhost-user support to passt (part 2)
2024-06-12 17:37 ` Stefano Brivio
@ 2024-06-12 21:23 ` Stefano Brivio
0 siblings, 0 replies; 25+ messages in thread
From: Stefano Brivio @ 2024-06-12 21:23 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
On Wed, 12 Jun 2024 19:37:44 +0200
Stefano Brivio <sbrivio@redhat.com> wrote:
> On Wed, 12 Jun 2024 19:16:17 +0200
> Stefano Brivio <sbrivio@redhat.com> wrote:
>
> > On Wed, 12 Jun 2024 17:47:26 +0200
> > Laurent Vivier <lvivier@redhat.com> wrote:
> >
> > > Extract buffers management code from tcp.c and move
> > > it to tcp_buf.c
> > > tcp.c keeps all the generic code and will be also used by
> > > the vhost-user functions.
> > >
> > > Also compare mode to MODE_PASTA, as we will manage vhost-user
> > > mode (MODE_VU) like MODE_PASST.
> >
> > Something in this series breaks the pasta_podman/bats test, number 19
> > in that script (Single TCP port forwarding, IPv4, tap). I'm bisecting
> > now...
>
> $ git bisect good
> 3c6a20486425ed00ba5b631bea11135045794dc2 is the first bad commit
> commit 3c6a20486425ed00ba5b631bea11135045794dc2
> Author: Laurent Vivier <lvivier@redhat.com>
> Date: Wed Jun 12 17:47:34 2024 +0200
>
> tap: use in->buf_size rather than sizeof(pkt_buf)
>
> buf_size is set to sizeof(pkt_buf) by default. And it seems more correct
> to provide the actual size of the buffer.
>
> Later a buf_size of 0 will allow vhost-user mode to detect
> guest memory buffers.
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
>
> tap.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> ...checking that patch now.
Ouch, sorry, bad bisect, I forgot to rebuild at every step. The actual
issue seems to be in 1/8 (details as a reply to that one):
$ git bisect bad
fa462103eb219dfb8e6fe7bb25d1707d8a82b2a2 is the first bad commit
commit fa462103eb219dfb8e6fe7bb25d1707d8a82b2a2
Author: Laurent Vivier <lvivier@redhat.com>
Date: Wed Jun 12 17:47:27 2024 +0200
tcp: extract buffer management from tcp_send_flag()
This commit isolates the internal data structure management used for storing
data (e.g., tcp4_l2_flags_iov[], tcp6_l2_flags_iov[], tcp4_flags_ip[],
tcp4_flags[], ...) from the tcp_send_flag() function. The extracted
functionality is relocated to a new function named tcp_fill_flag_header().
tcp_fill_flag_header() is now a generic function that accepts parameters such
as struct tcphdr and a data pointer. tcp_send_flag() utilizes this parameter to
pass memory pointers from tcp4_l2_flags_iov[] and tcp6_l2_flags_iov[].
This separation sets the stage for utilizing tcp_fill_flag_header() to
set the memory provided by the guest via vhost-user in future developments.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
tcp.c | 72 ++++++++++++++++++++++++++++++++++++++++++++-----------------------
1 file changed, 48 insertions(+), 24 deletions(-)
--
Stefano
^ permalink raw reply [flat|nested] 25+ messages in thread