[PATCH net-next v13 11/11] io_uring/zcrx: add selftest

[David Wei <dw@davidwei.uk>]

Add a selftest for io_uring zero copy Rx. This test cannot run locally
and requires a remote host to be configured in net.config. The remote
host must have hardware support for zero copy Rx as listed in the
documentation page. The test will restore the NIC config back to before
the test and is idempotent.

liburing is required to compile the test and be installed on the remote
host running the test.

Signed-off-by: David Wei <dw@davidwei.uk>
---
 .../selftests/drivers/net/hw/.gitignore       |   2 +
 .../testing/selftests/drivers/net/hw/Makefile |   5 +
 .../selftests/drivers/net/hw/iou-zcrx.c       | 426 ++++++++++++++++++
 .../selftests/drivers/net/hw/iou-zcrx.py      |  64 +++
 4 files changed, 497 insertions(+)
 create mode 100644 tools/testing/selftests/drivers/net/hw/iou-zcrx.c
 create mode 100755 tools/testing/selftests/drivers/net/hw/iou-zcrx.py

diff --git a/tools/testing/selftests/drivers/net/hw/.gitignore b/tools/testing/selftests/drivers/net/hw/.gitignore
index e9fe6ede681a..6942bf575497 100644
--- a/tools/testing/selftests/drivers/net/hw/.gitignore
+++ b/tools/testing/selftests/drivers/net/hw/.gitignore
@@ -1 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+iou-zcrx
 ncdevmem
diff --git a/tools/testing/selftests/drivers/net/hw/Makefile b/tools/testing/selftests/drivers/net/hw/Makefile
index 21ba64ce1e34..7efc47c89463 100644
--- a/tools/testing/selftests/drivers/net/hw/Makefile
+++ b/tools/testing/selftests/drivers/net/hw/Makefile
@@ -1,5 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0+ OR MIT
 
+TEST_GEN_FILES = iou-zcrx
+
 TEST_PROGS = \
 	csum.py \
 	devlink_port_split.py \
@@ -10,6 +12,7 @@ TEST_PROGS = \
 	ethtool_rmon.sh \
 	hw_stats_l3.sh \
 	hw_stats_l3_gre.sh \
+	iou-zcrx.py \
 	loopback.sh \
 	nic_link_layer.py \
 	nic_performance.py \
@@ -38,3 +41,5 @@ include ../../../lib.mk
 # YNL build
 YNL_GENS := ethtool netdev
 include ../../../net/ynl.mk
+
+$(OUTPUT)/iou-zcrx: LDLIBS += -luring
diff --git a/tools/testing/selftests/drivers/net/hw/iou-zcrx.c b/tools/testing/selftests/drivers/net/hw/iou-zcrx.c
new file mode 100644
index 000000000000..010c261d2132
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/iou-zcrx.c
@@ -0,0 +1,426 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <assert.h>
+#include <errno.h>
+#include <error.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <arpa/inet.h>
+#include <linux/errqueue.h>
+#include <linux/if_packet.h>
+#include <linux/ipv6.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <net/ethernet.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/tcp.h>
+#include <netinet/udp.h>
+#include <sys/epoll.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <sys/wait.h>
+
+#include <liburing.h>
+
+#define PAGE_SIZE (4096)
+#define AREA_SIZE (8192 * PAGE_SIZE)
+#define SEND_SIZE (512 * 4096)
+#define min(a, b) \
+	({ \
+		typeof(a) _a = (a); \
+		typeof(b) _b = (b); \
+		_a < _b ? _a : _b; \
+	})
+#define min_t(t, a, b) \
+	({ \
+		t _ta = (a); \
+		t _tb = (b); \
+		min(_ta, _tb); \
+	})
+
+#define ALIGN_UP(v, align) (((v) + (align) - 1) & ~((align) - 1))
+
+static int cfg_server;
+static int cfg_client;
+static int cfg_port = 8000;
+static int cfg_payload_len;
+static const char *cfg_ifname;
+static int cfg_queue_id = -1;
+static struct sockaddr_in6 cfg_addr;
+
+static char payload[SEND_SIZE] __attribute__((aligned(PAGE_SIZE)));
+static void *area_ptr;
+static void *ring_ptr;
+static size_t ring_size;
+static struct io_uring_zcrx_rq rq_ring;
+static unsigned long area_token;
+static int connfd;
+static bool stop;
+static size_t received;
+
+static unsigned long gettimeofday_ms(void)
+{
+	struct timeval tv;
+
+	gettimeofday(&tv, NULL);
+	return (tv.tv_sec * 1000) + (tv.tv_usec / 1000);
+}
+
+static int parse_address(const char *str, int port, struct sockaddr_in6 *sin6)
+{
+	int ret;
+
+	sin6->sin6_family = AF_INET6;
+	sin6->sin6_port = htons(port);
+
+	ret = inet_pton(sin6->sin6_family, str, &sin6->sin6_addr);
+	if (ret != 1) {
+		/* fallback to plain IPv4 */
+		ret = inet_pton(AF_INET, str, &sin6->sin6_addr.s6_addr32[3]);
+		if (ret != 1)
+			return -1;
+
+		/* add ::ffff prefix */
+		sin6->sin6_addr.s6_addr32[0] = 0;
+		sin6->sin6_addr.s6_addr32[1] = 0;
+		sin6->sin6_addr.s6_addr16[4] = 0;
+		sin6->sin6_addr.s6_addr16[5] = 0xffff;
+	}
+
+	return 0;
+}
+
+static inline size_t get_refill_ring_size(unsigned int rq_entries)
+{
+	size_t size;
+
+	ring_size = rq_entries * sizeof(struct io_uring_zcrx_rqe);
+	/* add space for the header (head/tail/etc.) */
+	ring_size += PAGE_SIZE;
+	return ALIGN_UP(ring_size, 4096);
+}
+
+static void setup_zcrx(struct io_uring *ring)
+{
+	unsigned int ifindex;
+	unsigned int rq_entries = 4096;
+	int ret;
+
+	ifindex = if_nametoindex(cfg_ifname);
+	if (!ifindex)
+		error(1, 0, "bad interface name: %s", cfg_ifname);
+
+	area_ptr = mmap(NULL,
+			AREA_SIZE,
+			PROT_READ | PROT_WRITE,
+			MAP_ANONYMOUS | MAP_PRIVATE,
+			0,
+			0);
+	if (area_ptr == MAP_FAILED)
+		error(1, 0, "mmap(): zero copy area");
+
+	ring_size = get_refill_ring_size(rq_entries);
+	ring_ptr = mmap(NULL,
+			ring_size,
+			PROT_READ | PROT_WRITE,
+			MAP_ANONYMOUS | MAP_PRIVATE,
+			0,
+			0);
+
+	struct io_uring_region_desc region_reg = {
+		.size = ring_size,
+		.user_addr = (__u64)(unsigned long)ring_ptr,
+		.flags = IORING_MEM_REGION_TYPE_USER,
+	};
+
+	struct io_uring_zcrx_area_reg area_reg = {
+		.addr = (__u64)(unsigned long)area_ptr,
+		.len = AREA_SIZE,
+		.flags = 0,
+	};
+
+	struct io_uring_zcrx_ifq_reg reg = {
+		.if_idx = ifindex,
+		.if_rxq = cfg_queue_id,
+		.rq_entries = rq_entries,
+		.area_ptr = (__u64)(unsigned long)&area_reg,
+		.region_ptr = (__u64)(unsigned long)&region_reg,
+	};
+
+	ret = io_uring_register_ifq(ring, &reg);
+	if (ret)
+		error(1, 0, "io_uring_register_ifq(): %d", ret);
+
+	rq_ring.khead = (unsigned int *)((char *)ring_ptr + reg.offsets.head);
+	rq_ring.ktail = (unsigned int *)((char *)ring_ptr + reg.offsets.tail);
+	rq_ring.rqes = (struct io_uring_zcrx_rqe *)((char *)ring_ptr + reg.offsets.rqes);
+	rq_ring.rq_tail = 0;
+	rq_ring.ring_entries = reg.rq_entries;
+
+	area_token = area_reg.rq_area_token;
+}
+
+static void add_accept(struct io_uring *ring, int sockfd)
+{
+	struct io_uring_sqe *sqe;
+
+	sqe = io_uring_get_sqe(ring);
+
+	io_uring_prep_accept(sqe, sockfd, NULL, NULL, 0);
+	sqe->user_data = 1;
+}
+
+static void add_recvzc(struct io_uring *ring, int sockfd)
+{
+	struct io_uring_sqe *sqe;
+
+	sqe = io_uring_get_sqe(ring);
+
+	io_uring_prep_rw(IORING_OP_RECV_ZC, sqe, sockfd, NULL, 0, 0);
+	sqe->ioprio |= IORING_RECV_MULTISHOT;
+	sqe->user_data = 2;
+}
+
+static void process_accept(struct io_uring *ring, struct io_uring_cqe *cqe)
+{
+	if (cqe->res < 0)
+		error(1, 0, "accept()");
+	if (connfd)
+		error(1, 0, "Unexpected second connection");
+
+	connfd = cqe->res;
+	add_recvzc(ring, connfd);
+}
+
+static void process_recvzc(struct io_uring *ring, struct io_uring_cqe *cqe)
+{
+	unsigned rq_mask = rq_ring.ring_entries - 1;
+	struct io_uring_zcrx_cqe *rcqe;
+	struct io_uring_zcrx_rqe *rqe;
+	struct io_uring_sqe *sqe;
+	uint64_t mask;
+	char *data;
+	ssize_t n;
+	int i;
+
+	if (cqe->res == 0 && cqe->flags == 0) {
+		stop = true;
+		return;
+	}
+
+	if (cqe->res < 0)
+		error(1, 0, "recvzc(): %d", cqe->res);
+
+	if (!(cqe->flags & IORING_CQE_F_MORE))
+		add_recvzc(ring, connfd);
+
+	rcqe = (struct io_uring_zcrx_cqe *)(cqe + 1);
+
+	n = cqe->res;
+	mask = (1ULL << IORING_ZCRX_AREA_SHIFT) - 1;
+	data = (char *)area_ptr + (rcqe->off & mask);
+
+	for (i = 0; i < n; i++) {
+		if (*(data + i) != payload[(received + i)])
+			error(1, 0, "payload mismatch");
+	}
+	received += n;
+
+	rqe = &rq_ring.rqes[(rq_ring.rq_tail & rq_mask)];
+	rqe->off = (rcqe->off & ~IORING_ZCRX_AREA_MASK) | area_token;
+	rqe->len = cqe->res;
+	io_uring_smp_store_release(rq_ring.ktail, ++rq_ring.rq_tail);
+}
+
+static void server_loop(struct io_uring *ring)
+{
+	struct io_uring_cqe *cqe;
+	unsigned int count = 0;
+	unsigned int head;
+	int i, ret;
+
+	io_uring_submit_and_wait(ring, 1);
+
+	io_uring_for_each_cqe(ring, head, cqe) {
+		if (cqe->user_data == 1)
+			process_accept(ring, cqe);
+		else if (cqe->user_data == 2)
+			process_recvzc(ring, cqe);
+		else
+			error(1, 0, "unknown cqe");
+		count++;
+	}
+	io_uring_cq_advance(ring, count);
+}
+
+static void run_server(void)
+{
+	unsigned int flags = 0;
+	struct io_uring ring;
+	int fd, enable, ret;
+	uint64_t tstop;
+
+	fd = socket(AF_INET6, SOCK_STREAM, 0);
+	if (fd == -1)
+		error(1, 0, "socket()");
+
+	enable = 1;
+	ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(int));
+	if (ret < 0)
+		error(1, 0, "setsockopt(SO_REUSEADDR)");
+
+	ret = bind(fd, &cfg_addr, sizeof(cfg_addr));
+	if (ret < 0)
+		error(1, 0, "bind()");
+
+	if (listen(fd, 1024) < 0)
+		error(1, 0, "listen()");
+
+	flags |= IORING_SETUP_COOP_TASKRUN;
+	flags |= IORING_SETUP_SINGLE_ISSUER;
+	flags |= IORING_SETUP_DEFER_TASKRUN;
+	flags |= IORING_SETUP_SUBMIT_ALL;
+	flags |= IORING_SETUP_CQE32;
+
+	io_uring_queue_init(512, &ring, flags);
+
+	setup_zcrx(&ring);
+
+	add_accept(&ring, fd);
+
+	tstop = gettimeofday_ms() + 5000;
+	while (!stop && gettimeofday_ms() < tstop)
+		server_loop(&ring);
+
+	if (!stop)
+		error(1, 0, "test failed\n");
+}
+
+static void run_client(void)
+{
+	ssize_t to_send = SEND_SIZE;
+	ssize_t sent = 0;
+	ssize_t chunk, res;
+	int fd;
+
+	fd = socket(AF_INET6, SOCK_STREAM, 0);
+	if (fd == -1)
+		error(1, 0, "socket()");
+
+	if (connect(fd, &cfg_addr, sizeof(cfg_addr)))
+		error(1, 0, "connect()");
+
+	while (to_send) {
+		void *src = &payload[sent];
+
+		chunk = min_t(ssize_t, cfg_payload_len, to_send);
+		res = send(fd, src, chunk, 0);
+		if (res < 0)
+			error(1, 0, "send(): %d", sent);
+		sent += res;
+		to_send -= res;
+	}
+
+	close(fd);
+}
+
+static void usage(const char *filepath)
+{
+	error(1, 0, "Usage: %s (-4|-6) (-s|-c) -h<server_ip> -p<port> "
+		    "-l<payload_size> -i<ifname> -q<rxq_id>", filepath);
+}
+
+static void parse_opts(int argc, char **argv)
+{
+	const int max_payload_len = sizeof(payload) -
+				    sizeof(struct ipv6hdr) -
+				    sizeof(struct tcphdr) -
+				    40 /* max tcp options */;
+	struct sockaddr_in6 *addr6 = (void *) &cfg_addr;
+	char *addr = NULL;
+	int ret;
+	int c;
+
+	if (argc <= 1)
+		usage(argv[0]);
+	cfg_payload_len = max_payload_len;
+
+	while ((c = getopt(argc, argv, "46sch:p:l:i:q:")) != -1) {
+		switch (c) {
+		case 's':
+			if (cfg_client)
+				error(1, 0, "Pass one of -s or -c");
+			cfg_server = 1;
+			break;
+		case 'c':
+			if (cfg_server)
+				error(1, 0, "Pass one of -s or -c");
+			cfg_client = 1;
+			break;
+		case 'h':
+			addr = optarg;
+			break;
+		case 'p':
+			cfg_port = strtoul(optarg, NULL, 0);
+			break;
+		case 'l':
+			cfg_payload_len = strtoul(optarg, NULL, 0);
+			break;
+		case 'i':
+			cfg_ifname = optarg;
+			break;
+		case 'q':
+			cfg_queue_id = strtoul(optarg, NULL, 0);
+			break;
+		}
+	}
+
+	if (cfg_server && addr)
+		error(1, 0, "Receiver cannot have -h specified");
+
+	memset(addr6, 0, sizeof(*addr6));
+	addr6->sin6_family = AF_INET6;
+	addr6->sin6_port = htons(cfg_port);
+	addr6->sin6_addr = in6addr_any;
+	if (addr) {
+		ret = parse_address(addr, cfg_port, addr6);
+		if (ret)
+			error(1, 0, "receiver address parse error: %s", addr);
+	}
+
+	if (cfg_payload_len > max_payload_len)
+		error(1, 0, "-l: payload exceeds max (%d)", max_payload_len);
+}
+
+int main(int argc, char **argv)
+{
+	const char *cfg_test = argv[argc - 1];
+	int i;
+
+	parse_opts(argc, argv);
+
+	for (i = 0; i < SEND_SIZE; i++)
+		payload[i] = 'a' + (i % 26);
+
+	if (cfg_server)
+		run_server();
+	else if (cfg_client)
+		run_client();
+
+	return 0;
+}
diff --git a/tools/testing/selftests/drivers/net/hw/iou-zcrx.py b/tools/testing/selftests/drivers/net/hw/iou-zcrx.py
new file mode 100755
index 000000000000..ea0a346c3eff
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/iou-zcrx.py
@@ -0,0 +1,64 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+import re
+from os import path
+from lib.py import ksft_run, ksft_exit
+from lib.py import NetDrvEpEnv
+from lib.py import bkg, cmd, ethtool, wait_port_listen
+
+
+def _get_rx_ring_entries(cfg):
+    output = ethtool(f"-g {cfg.ifname}", host=cfg.remote).stdout
+    values = re.findall(r'RX:\s+(\d+)', output)
+    return int(values[1])
+
+
+def _get_combined_channels(cfg):
+    output = ethtool(f"-l {cfg.ifname}", host=cfg.remote).stdout
+    values = re.findall(r'Combined:\s+(\d+)', output)
+    return int(values[1])
+
+
+def _set_flow_rule(cfg, chan):
+    output = ethtool(f"-N {cfg.ifname} flow-type tcp6 dst-port 9999 action {chan}", host=cfg.remote).stdout
+    values = re.search(r'ID (\d+)', output).group(1)
+    return int(values)
+
+
+def test_zcrx(cfg) -> None:
+    cfg.require_v6()
+
+    combined_chans = _get_combined_channels(cfg)
+    if combined_chans < 2:
+        raise KsftSkipEx('at least 2 combined channels required')
+    rx_ring = _get_rx_ring_entries(cfg)
+
+    rx_cmd = f"{cfg.bin_remote} -s -p 9999 -i {cfg.ifname} -q {combined_chans - 1}"
+    tx_cmd = f"{cfg.bin_local} -c -h {cfg.remote_v6} -p 9999 -l 12840"
+
+    try:
+        ethtool(f"-G {cfg.ifname} rx 64", host=cfg.remote)
+        ethtool(f"-X {cfg.ifname} equal {combined_chans - 1}", host=cfg.remote)
+        flow_rule_id = _set_flow_rule(cfg, combined_chans - 1)
+
+        with bkg(rx_cmd, host=cfg.remote, exit_wait=True):
+            wait_port_listen(9999, proto="tcp", host=cfg.remote)
+            cmd(tx_cmd)
+    finally:
+        ethtool(f"-N {cfg.ifname} delete {flow_rule_id}", host=cfg.remote)
+        ethtool(f"-X {cfg.ifname} default", host=cfg.remote)
+        ethtool(f"-G {cfg.ifname} rx {rx_ring}", host=cfg.remote)
+
+
+def main() -> None:
+    with NetDrvEpEnv(__file__) as cfg:
+        cfg.bin_local = path.abspath(path.dirname(__file__) + "/../../../drivers/net/hw/iou-zcrx")
+        cfg.bin_remote = cfg.remote.deploy(cfg.bin_local)
+
+        ksft_run(globs=globals(), case_pfx={"test_"}, args=(cfg, ))
+    ksft_exit()
+
+
+if __name__ == "__main__":
+    main()
-- 
2.43.5