* [PATCH v7 0/8] Add vhost-user support to passt (part 2)
@ 2024-06-13 12:36 Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 1/8] tcp: extract buffer management from tcp_send_flag() Laurent Vivier
` (8 more replies)
0 siblings, 9 replies; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
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.
v7:
- update comments (tap_flush_pools(), func and line)
- drop "-L4" in tcp_buf.c header
- fix *optlen initializatio
- fix tcp4_flags_used/tcp6_flags_used value on error
- fix seq_to_tap value
v6:
- reorder declarations, align summing, add curly brackets
- 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()
- rename tcp_fill_flag_header() to tcp_prepare_flags()
- set optlen to 0 in tcp_prepare_flags()
v5:
- remove:
[PATCH v4 01/10] tcp: inline tcp_l2_buf_fill_headers()
- merge
[PATCH v4 09/10] tcp: remove tap_hdr parameter
into tcp: extract buffer management from tcp_send_flag()
- update comments
v4:
- remove "tcp: extract buffer management from tcp_conn_tap_mss()"
as the MSS size can be the same between socket and vhost-user.
- rename tcp_send_flag() and tcp_data_from_sock() to
tcp_buf_send_flag() and tcp_buf_data_from_sock()
v3:
- add 3 new patches
tap: use in->buf_size rather than sizeof(pkt_buf)
tcp: remove tap_hdr parameter
iov: remove iov_copy()
v2:
- compare to MODE_PASTA in conf_open_files() too
- move taph out of udp_update_hdr4()/udp_update_hdr6()
Laurent Vivier (8):
tcp: extract buffer management from tcp_send_flag()
tcp: move buffers management functions to their own file
tap: refactor packets handling functions
udp: refactor UDP header update functions
udp: rename udp_sock_handler() to udp_buf_sock_handler()
vhost-user: compare mode MODE_PASTA and not MODE_PASST
iov: remove iov_copy()
tap: use in->buf_size rather than sizeof(pkt_buf)
Makefile | 5 +-
conf.c | 14 +-
iov.c | 39 ----
iov.h | 3 -
isolation.c | 10 +-
passt.c | 4 +-
tap.c | 132 ++++++-----
tap.h | 3 +
tcp.c | 580 ++++---------------------------------------------
tcp_buf.c | 519 +++++++++++++++++++++++++++++++++++++++++++
tcp_buf.h | 16 ++
tcp_internal.h | 96 ++++++++
udp.c | 68 +++---
udp.h | 2 +-
14 files changed, 803 insertions(+), 688 deletions(-)
create mode 100644 tcp_buf.c
create mode 100644 tcp_buf.h
create mode 100644 tcp_internal.h
--
2.45.2
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v7 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
@ 2024-06-13 12:36 ` Laurent Vivier
2024-06-13 12:58 ` Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 2/8] tcp: move buffers management functions to their own file Laurent Vivier
` (7 subsequent siblings)
8 siblings, 1 reply; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 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>
---
tcp.c | 78 +++++++++++++++++++++++++++++++++++++++++------------------
1 file changed, 54 insertions(+), 24 deletions(-)
diff --git a/tcp.c b/tcp.c
index dd8d46e08628..e40f42259451 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 +1607,12 @@ 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;
-
+ *optlen = 0;
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;
@@ -1653,17 +1646,13 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
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 +1667,47 @@ 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;
+ uint32_t seq;
+ 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;
+
+ seq = conn->seq_to_tap;
+ ret = tcp_prepare_flags(c, conn, flags, &payload->th,
+ payload->opts, &optlen);
+ 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, seq);
+ 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 +1607,12 @@ 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;
-
+ *optlen = 0;
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;
@@ -1653,17 +1646,13 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
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 +1667,47 @@ 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;
+ uint32_t seq;
+ 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;
+
+ seq = conn->seq_to_tap;
+ ret = tcp_prepare_flags(c, conn, flags, &payload->th,
+ payload->opts, &optlen);
+ 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, seq);
+ 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] 12+ messages in thread
* [PATCH v7 2/8] tcp: move buffers management functions to their own file
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 1/8] tcp: extract buffer management from tcp_send_flag() Laurent Vivier
@ 2024-06-13 12:36 ` Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 3/8] tap: refactor packets handling functions Laurent Vivier
` (6 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 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>
---
Makefile | 5 +-
tcp.c | 568 ++-----------------------------------------------
tcp_buf.c | 519 ++++++++++++++++++++++++++++++++++++++++++++
tcp_buf.h | 16 ++
tcp_internal.h | 96 +++++++++
5 files changed, 654 insertions(+), 550 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 e40f42259451..68524235347c 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);
@@ -1678,60 +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;
- uint32_t seq;
- 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;
-
- seq = conn->seq_to_tap;
- ret = tcp_prepare_flags(c, conn, flags, &payload->th,
- payload->opts, &optlen);
- 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, seq);
- 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);
}
/**
@@ -1739,7 +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;
@@ -2166,49 +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
@@ -2220,123 +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..5f4df5bb3b0c
--- /dev/null
+++ b/tcp_buf.c
@@ -0,0 +1,519 @@
+// 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 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;
+ uint32_t seq;
+ 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;
+
+ seq = conn->seq_to_tap;
+ ret = tcp_prepare_flags(c, conn, flags, &payload->th,
+ payload->opts, &optlen);
+ 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, seq);
+ 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] 12+ messages in thread
* [PATCH v7 3/8] tap: refactor packets handling functions
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 1/8] tcp: extract buffer management from tcp_send_flag() Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 2/8] tcp: move buffers management functions to their own file Laurent Vivier
@ 2024-06-13 12:36 ` Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 4/8] udp: refactor UDP header update functions Laurent Vivier
` (5 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 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>
---
tap.c | 110 ++++++++++++++++++++++++++++++++--------------------------
tap.h | 3 ++
2 files changed, 64 insertions(+), 49 deletions(-)
diff --git a/tap.c b/tap.c
index 26084b486519..46ea24a8e793 100644
--- a/tap.c
+++ b/tap.c
@@ -921,6 +921,58 @@ append:
return in->count;
}
+/**
+ * tap_flush_pools() - 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
+ */
+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 +999,6 @@ 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 +1011,7 @@ 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 +1038,18 @@ 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 +1074,18 @@ 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 +1096,7 @@ 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] 12+ messages in thread
* [PATCH v7 4/8] udp: refactor UDP header update functions
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (2 preceding siblings ...)
2024-06-13 12:36 ` [PATCH v7 3/8] tap: refactor packets handling functions Laurent Vivier
@ 2024-06-13 12:36 ` Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 5/8] udp: rename udp_sock_handler() to udp_buf_sock_handler() Laurent Vivier
` (4 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 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>
---
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] 12+ messages in thread
* [PATCH v7 5/8] udp: rename udp_sock_handler() to udp_buf_sock_handler()
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (3 preceding siblings ...)
2024-06-13 12:36 ` [PATCH v7 4/8] udp: refactor UDP header update functions Laurent Vivier
@ 2024-06-13 12:36 ` Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 6/8] vhost-user: compare mode MODE_PASTA and not MODE_PASST Laurent Vivier
` (3 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 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] 12+ messages in thread
* [PATCH v7 6/8] vhost-user: compare mode MODE_PASTA and not MODE_PASST
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (4 preceding siblings ...)
2024-06-13 12:36 ` [PATCH v7 5/8] udp: rename udp_sock_handler() to udp_buf_sock_handler() Laurent Vivier
@ 2024-06-13 12:36 ` Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 7/8] iov: remove iov_copy() Laurent Vivier
` (2 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 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>
---
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 46ea24a8e793..2a749809eaab 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",
@@ -1330,7 +1330,9 @@ 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
@@ -1338,7 +1340,5 @@ 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 5f4df5bb3b0c..ff9f7970ee0c 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] 12+ messages in thread
* [PATCH v7 7/8] iov: remove iov_copy()
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (5 preceding siblings ...)
2024-06-13 12:36 ` [PATCH v7 6/8] vhost-user: compare mode MODE_PASTA and not MODE_PASST Laurent Vivier
@ 2024-06-13 12:36 ` Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 8/8] tap: use in->buf_size rather than sizeof(pkt_buf) Laurent Vivier
2024-06-13 14:34 ` [PATCH v7 0/8] Add vhost-user support to passt (part 2) Stefano Brivio
8 siblings, 0 replies; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 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] 12+ messages in thread
* [PATCH v7 8/8] tap: use in->buf_size rather than sizeof(pkt_buf)
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (6 preceding siblings ...)
2024-06-13 12:36 ` [PATCH v7 7/8] iov: remove iov_copy() Laurent Vivier
@ 2024-06-13 12:36 ` Laurent Vivier
2024-06-13 14:34 ` [PATCH v7 0/8] Add vhost-user support to passt (part 2) Stefano Brivio
8 siblings, 0 replies; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:36 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 2a749809eaab..c9aeff19f177 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] 12+ messages in thread
* Re: [PATCH v7 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 12:36 ` [PATCH v7 1/8] tcp: extract buffer management from tcp_send_flag() Laurent Vivier
@ 2024-06-13 12:58 ` Laurent Vivier
2024-06-13 13:43 ` Stefano Brivio
0 siblings, 1 reply; 12+ messages in thread
From: Laurent Vivier @ 2024-06-13 12:58 UTC (permalink / raw)
To: passt-dev
On 13/06/2024 14:36, Laurent Vivier 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.
Forgot to update the comment: s/tcp_fill_flag_header/tcp_prepare_flags/
Could you update on merge?
Thanks,
Laurent
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> tcp.c | 78 +++++++++++++++++++++++++++++++++++++++++------------------
> 1 file changed, 54 insertions(+), 24 deletions(-)
>
> diff --git a/tcp.c b/tcp.c
> index dd8d46e08628..e40f42259451 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 +1607,12 @@ 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;
> -
> + *optlen = 0;
> 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;
> @@ -1653,17 +1646,13 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags)
> 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 +1667,47 @@ 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;
> + uint32_t seq;
> + 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;
> +
> + seq = conn->seq_to_tap;
> + ret = tcp_prepare_flags(c, conn, flags, &payload->th,
> + payload->opts, &optlen);
> + 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, seq);
> + iov[TCP_IOV_PAYLOAD].iov_len = l4len;
> +
> if (flags & DUP_ACK) {
> struct iovec *dup_iov;
> int i;
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v7 1/8] tcp: extract buffer management from tcp_send_flag()
2024-06-13 12:58 ` Laurent Vivier
@ 2024-06-13 13:43 ` Stefano Brivio
0 siblings, 0 replies; 12+ messages in thread
From: Stefano Brivio @ 2024-06-13 13:43 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
On Thu, 13 Jun 2024 14:58:42 +0200
Laurent Vivier <lvivier@redhat.com> wrote:
> On 13/06/2024 14:36, Laurent Vivier 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.
>
> Forgot to update the comment: s/tcp_fill_flag_header/tcp_prepare_flags/
>
> Could you update on merge?
Sure. Running tests now...
--
Stefano
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v7 0/8] Add vhost-user support to passt (part 2)
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
` (7 preceding siblings ...)
2024-06-13 12:36 ` [PATCH v7 8/8] tap: use in->buf_size rather than sizeof(pkt_buf) Laurent Vivier
@ 2024-06-13 14:34 ` Stefano Brivio
8 siblings, 0 replies; 12+ messages in thread
From: Stefano Brivio @ 2024-06-13 14:34 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev, David Gibson
On Thu, 13 Jun 2024 14:36:47 +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.
>
> v7:
> - update comments (tap_flush_pools(), func and line)
> - drop "-L4" in tcp_buf.c header
> - fix *optlen initializatio
> - fix tcp4_flags_used/tcp6_flags_used value on error
> - fix seq_to_tap value
Applied!
--
Stefano
^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2024-06-13 14:35 UTC | newest]
Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-06-13 12:36 [PATCH v7 0/8] Add vhost-user support to passt (part 2) Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 1/8] tcp: extract buffer management from tcp_send_flag() Laurent Vivier
2024-06-13 12:58 ` Laurent Vivier
2024-06-13 13:43 ` Stefano Brivio
2024-06-13 12:36 ` [PATCH v7 2/8] tcp: move buffers management functions to their own file Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 3/8] tap: refactor packets handling functions Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 4/8] udp: refactor UDP header update functions Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 5/8] udp: rename udp_sock_handler() to udp_buf_sock_handler() Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 6/8] vhost-user: compare mode MODE_PASTA and not MODE_PASST Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 7/8] iov: remove iov_copy() Laurent Vivier
2024-06-13 12:36 ` [PATCH v7 8/8] tap: use in->buf_size rather than sizeof(pkt_buf) Laurent Vivier
2024-06-13 14:34 ` [PATCH v7 0/8] Add vhost-user support to passt (part 2) Stefano Brivio
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