[PATCH v9 15/15] net/pcap: add snapshot length devarg

Stephen Hemminger
2026-01-28T18:43:01Z

Add a new devarg 'snaplen' to configure the pcap snapshot length,
which controls the maximum packet size for capture and output.

The snapshot length affects:
- The pcap_set_snaplen() call when capturing from interfaces
- The pcap_open_dead() snapshot parameter for output files
- The reported max_rx_pktlen in device info
- The reported max_mtu in device info (snaplen - ethernet header)

The default value is 65535 bytes, preserving backward compatibility
with previous driver behavior.

Example usage:
--vdev 'net_pcap0,iface=eth0,snaplen=1518'
--vdev 'net_pcap0,rx_pcap=in.pcap,tx_pcap=out.pcap,snaplen=9000'

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
app/test/test_pmd_pcap.c | 194 ++++++++++++++++++++++++-
doc/guides/nics/pcap_ring.rst | 17 +++
doc/guides/rel_notes/release_26_03.rst | 1 +
drivers/net/pcap/pcap_ethdev.c | 165 ++++++++++++---------
4 files changed, 306 insertions(+), 71 deletions(-)

diff --git a/app/test/test_pmd_pcap.c b/app/test/test_pmd_pcap.c
index 8c5d5d76e4..86ec6165f3 100644
--- a/app/test/test_pmd_pcap.c
+++ b/app/test/test_pmd_pcap.c
@@ -447,6 +447,41 @@ get_pcap_packet_sizes(const char *path, uint16_t *sizes, unsigned int max_pkts)
return count;
}

+/*
+ * Helper: Verify packets in pcap file are truncated correctly
+ * Returns 0 if all packets have caplen == expected_caplen and len == expected_len
+ */
+static int
+verify_pcap_truncation(const char *path, uint32_t expected_caplen,
+ uint32_t expected_len, unsigned int *pkt_count)
+{
+ pcap_t *pd;
+ char errbuf[PCAP_ERRBUF_SIZE];
+ struct pcap_pkthdr *hdr;
+ const u_char *data;
+ unsigned int count = 0;
+
+ pd = pcap_open_offline(path, errbuf);
+ if (pd == NULL)
+ return -1;
+
+ while (pcap_next_ex(pd, &hdr, &data) == 1) {
+ if (hdr->caplen != expected_caplen || hdr->len != expected_len) {
+ printf("Packet %u: caplen=%u (expected %u), len=%u (expected %u)\n",
+ count, hdr->caplen, expected_caplen,
+ hdr->len, expected_len);
+ pcap_close(pd);
+ return -1;
+ }
+ count++;
+ }
+
+ pcap_close(pd);
+ if (pkt_count)
+ *pkt_count = count;
+ return 0;
+}
+
/*
* Helper: Configure and start a pcap ethdev port
*/
@@ -1973,7 +2008,7 @@ test_multi_rx_queue_same_file(void)
* This test verifies that rte_eth_dev_info_get() returns correct values:
* 1. max_rx_queues matches the number of rx_pcap files passed
* 2. max_tx_queues matches the number of tx_pcap files passed
- * 3. min_mtu and max_mtu are set to reasonable values
+ * 3. max_rx_pktlen and max_mtu are based on default snapshot length
*/
static int
test_dev_info(void)
@@ -1985,6 +2020,9 @@ test_dev_info(void)
uint16_t port_id;
int ret;
unsigned int i;
+ /* Default snapshot length is 65535 */
+ const uint32_t default_snaplen = 65535;
+ const uint32_t expected_max_mtu = default_snaplen - RTE_ETHER_HDR_LEN;

printf("Testing device info reporting\n");

@@ -2023,8 +2061,8 @@ test_dev_info(void)
printf(" driver_name: %s\n", dev_info.driver_name);
printf(" max_rx_queues: %u (expected: 3)\n", dev_info.max_rx_queues);
printf(" max_tx_queues: %u (expected: 2)\n", dev_info.max_tx_queues);
- printf(" min_mtu: %u\n", dev_info.min_mtu);
- printf(" max_mtu: %u\n", dev_info.max_mtu);
+ printf(" max_rx_pktlen: %u (expected: %u)\n", dev_info.max_rx_pktlen, default_snaplen);
+ printf(" max_mtu: %u (expected: %u)\n", dev_info.max_mtu, expected_max_mtu);

/* Verify queue counts match number of pcap files */
TEST_ASSERT_EQUAL(dev_info.max_rx_queues, 3U,
@@ -2032,6 +2070,16 @@ test_dev_info(void)
TEST_ASSERT_EQUAL(dev_info.max_tx_queues, 2U,
"max_tx_queues mismatch: expected 2, got %u", dev_info.max_tx_queues);

+ /* Verify max_rx_pktlen equals default snapshot length */
+ TEST_ASSERT_EQUAL(dev_info.max_rx_pktlen, default_snaplen,
+ "max_rx_pktlen mismatch: expected %u, got %u",
+ default_snaplen, dev_info.max_rx_pktlen);
+
+ /* Verify max_mtu is snapshot_len minus ethernet header */
+ TEST_ASSERT_EQUAL(dev_info.max_mtu, expected_max_mtu,
+ "max_mtu mismatch: expected %u, got %u",
+ expected_max_mtu, dev_info.max_mtu);
+
rte_vdev_uninit("net_pcap_devinfo");

/* Cleanup temp files */
@@ -2044,6 +2092,144 @@ test_dev_info(void)
return TEST_SUCCESS;
}

+/*
+ * Test: Custom snapshot length (snaplen) parameter
+ *
+ * This test verifies that the snaplen devarg works correctly:
+ * 1. max_rx_pktlen reflects the custom snapshot length
+ * 2. max_mtu is calculated as snaplen - ethernet header
+ */
+static int
+test_snaplen(void)
+{
+ struct rte_eth_dev_info dev_info;
+ char devargs[512];
+ char rx_path[PATH_MAX];
+ char tx_path[PATH_MAX];
+ uint16_t port_id;
+ int ret;
+ const uint32_t custom_snaplen = 9000;
+ const uint32_t expected_max_mtu = custom_snaplen - RTE_ETHER_HDR_LEN;
+
+ printf("Testing custom snapshot length parameter\n");
+
+ /* Create temp files */
+ TEST_ASSERT(create_temp_path(rx_path, sizeof(rx_path), "pcap_snaplen_rx") == 0,
+ "Failed to create RX temp path");
+ TEST_ASSERT(create_test_pcap(rx_path, 1) == 0,
+ "Failed to create RX pcap");
+ TEST_ASSERT(create_temp_path(tx_path, sizeof(tx_path), "pcap_snaplen_tx") == 0,
+ "Failed to create TX temp path");
+
+ /* Create device with custom snaplen */
+ snprintf(devargs, sizeof(devargs), "rx_pcap=%s,tx_pcap=%s,snaplen=%u",
+ rx_path, tx_path, custom_snaplen);
+
+ ret = rte_vdev_init("net_pcap_snaplen", devargs);
+ TEST_ASSERT_SUCCESS(ret, "Failed to create pcap PMD: %s", rte_strerror(-ret));
+
+ ret = rte_eth_dev_get_port_by_name("net_pcap_snaplen", &port_id);
+ TEST_ASSERT_SUCCESS(ret, "Cannot find added pcap device");
+
+ ret = rte_eth_dev_info_get(port_id, &dev_info);
+ TEST_ASSERT_SUCCESS(ret, "Failed to get device info: %s", rte_strerror(-ret));
+
+ printf(" Custom snaplen: %u\n", custom_snaplen);
+ printf(" max_rx_pktlen: %u (expected: %u)\n", dev_info.max_rx_pktlen, custom_snaplen);
+ printf(" max_mtu: %u (expected: %u)\n", dev_info.max_mtu, expected_max_mtu);
+
+ /* Verify max_rx_pktlen equals custom snapshot length */
+ TEST_ASSERT_EQUAL(dev_info.max_rx_pktlen, custom_snaplen,
+ "max_rx_pktlen mismatch: expected %u, got %u",
+ custom_snaplen, dev_info.max_rx_pktlen);
+
+ /* Verify max_mtu is snaplen minus ethernet header */
+ TEST_ASSERT_EQUAL(dev_info.max_mtu, expected_max_mtu,
+ "max_mtu mismatch: expected %u, got %u",
+ expected_max_mtu, dev_info.max_mtu);
+
+ rte_vdev_uninit("net_pcap_snaplen");
+
+ /* Cleanup temp files */
+ unlink(rx_path);
+ unlink(tx_path);
+
+ printf("Snapshot length test PASSED\n");
+ return TEST_SUCCESS;
+}
+
+/*
+ * Test: Snapshot length truncation behavior
+ *
+ * This test verifies that packets larger than snaplen are properly truncated
+ * when written to pcap files:
+ * 1. caplen in pcap header is limited to snaplen
+ * 2. len in pcap header preserves original packet length
+ * 3. Only snaplen bytes of data are written
+ */
+static int
+test_snaplen_truncation(void)
+{
+ struct rte_mbuf *mbufs[NUM_PACKETS];
+ char devargs[512];
+ char tx_path[PATH_MAX];
+ uint16_t port_id;
+ int ret, nb_tx, nb_gen;
+ unsigned int pkt_count;
+ const uint32_t test_snaplen = 100;
+ const uint8_t pkt_size = 200;
+
+ printf("Testing snaplen truncation behavior\n");
+
+ /* Create temp TX file */
+ TEST_ASSERT(create_temp_path(tx_path, sizeof(tx_path), "pcap_trunc_tx") == 0,
+ "Failed to create TX temp path");
+
+ /* Create device with small snaplen */
+ snprintf(devargs, sizeof(devargs), "tx_pcap=%s,snaplen=%u",
+ tx_path, test_snaplen);
+
+ ret = rte_vdev_init("net_pcap_trunc", devargs);
+ TEST_ASSERT_SUCCESS(ret, "Failed to create pcap PMD: %s", rte_strerror(-ret));
+
+ ret = rte_eth_dev_get_port_by_name("net_pcap_trunc", &port_id);
+ TEST_ASSERT_SUCCESS(ret, "Cannot find added pcap device");
+
+ TEST_ASSERT(setup_pcap_port(port_id) == 0, "Failed to setup port");
+
+ /* Generate packets larger than snaplen */
+ nb_gen = generate_test_packets(mp, mbufs, NUM_PACKETS, pkt_size);
+ TEST_ASSERT_EQUAL(nb_gen, NUM_PACKETS,
+ "Failed to generate packets: got %d, expected %d",
+ nb_gen, NUM_PACKETS);
+
+ printf(" Sending %d packets of size %u with snaplen=%u\n",
+ NUM_PACKETS, pkt_size, test_snaplen);
+
+ /* Transmit packets */
+ nb_tx = rte_eth_tx_burst(port_id, 0, mbufs, NUM_PACKETS);
+ TEST_ASSERT_EQUAL(nb_tx, NUM_PACKETS,
+ "TX burst failed: sent %d/%d", nb_tx, NUM_PACKETS);
+
+ cleanup_pcap_vdev("net_pcap_trunc", port_id);
+
+ /* Verify truncation in output file */
+ ret = verify_pcap_truncation(tx_path, test_snaplen, pkt_size, &pkt_count);
+ TEST_ASSERT_SUCCESS(ret, "Truncation verification failed");
+ TEST_ASSERT_EQUAL(pkt_count, (unsigned int)NUM_PACKETS,
+ "Packet count mismatch: got %u, expected %d",
+ pkt_count, NUM_PACKETS);
+
+ printf(" Verified %u packets: caplen=%u, len=%u\n",
+ pkt_count, test_snaplen, pkt_size);
+
+ /* Cleanup */
+ unlink(tx_path);
+
+ printf("Snaplen truncation test PASSED\n");
+ return TEST_SUCCESS;
+}
+
/*
* Test: VLAN Strip on RX
*
@@ -2322,6 +2508,8 @@ static struct unit_test_suite test_pmd_pcap_suite = {
TEST_CASE(test_vlan_strip_rx),
TEST_CASE(test_vlan_insert_tx),
TEST_CASE(test_vlan_no_strip_rx),
+ TEST_CASE(test_snaplen),
+ TEST_CASE(test_snaplen_truncation),
TEST_CASES_END()
}
};
diff --git a/doc/guides/nics/pcap_ring.rst b/doc/guides/nics/pcap_ring.rst
index 6955e91130..f01107841d 100644
--- a/doc/guides/nics/pcap_ring.rst
+++ b/doc/guides/nics/pcap_ring.rst
@@ -94,6 +94,23 @@ The different stream types are:

iface=eth0

+* snaplen: Set snapshot length (maximum capture size)
+
+ The snapshot length limits the maximum size of captured packets. This can be
+ set with the ``snaplen`` devarg, for example::
+
+ snaplen=1518
+
+ This sets the snapshot length to 1518 bytes. The value affects the reported
+ ``max_rx_pktlen`` and ``max_mtu`` in device info. The default value is 65535
+ bytes, matching the default pcap snapshot length.
+
+ When capturing from interfaces, this limits the amount of data captured per
+ packet. For pcap file output, packets larger than the snapshot length are
+ truncated: only the first ``snaplen`` bytes are written, while the original
+ packet length is preserved in the pcap packet header.
+
+
Runtime Config Options
^^^^^^^^^^^^^^^^^^^^^^

diff --git a/doc/guides/rel_notes/release_26_03.rst b/doc/guides/rel_notes/release_26_03.rst
index ddcb693166..edb39f2a37 100644
--- a/doc/guides/rel_notes/release_26_03.rst
+++ b/doc/guides/rel_notes/release_26_03.rst
@@ -60,6 +60,7 @@ New Features
* Changed transmit burst to always return the number of packets requested.
Failed sends are counted as transmit errors.
* Added support for VLAN insertion and stripping.
+ * Added ``snaplen`` devarg to configure packet capture snapshot length.
* Receive timestamp offload is only done if offload flag set.
* Receive timestamps support nanosecond precision.
* Added unit test suite.
diff --git a/drivers/net/pcap/pcap_ethdev.c b/drivers/net/pcap/pcap_ethdev.c
index cc72f7f657..82ead5f136 100644
--- a/drivers/net/pcap/pcap_ethdev.c
+++ b/drivers/net/pcap/pcap_ethdev.c
@@ -31,8 +31,6 @@

#include "pcap_osdep.h"

-#define RTE_ETH_PCAP_SNAPSHOT_LEN 65535
-
#define ETH_PCAP_RX_PCAP_ARG "rx_pcap"
#define ETH_PCAP_TX_PCAP_ARG "tx_pcap"
#define ETH_PCAP_RX_IFACE_ARG "rx_iface"
@@ -41,6 +39,9 @@
#define ETH_PCAP_IFACE_ARG "iface"
#define ETH_PCAP_PHY_MAC_ARG "phy_mac"
#define ETH_PCAP_INFINITE_RX_ARG "infinite_rx"
+#define ETH_PCAP_SNAPSHOT_LEN_ARG "snaplen"
+
+#define ETH_PCAP_SNAPSHOT_LEN_DEFAULT 65535

#define ETH_PCAP_ARG_MAXLEN 64

@@ -98,6 +99,7 @@ struct pmd_internals {
char devargs[ETH_PCAP_ARG_MAXLEN];
struct rte_ether_addr eth_addr;
int if_index;
+ uint32_t snapshot_len;
bool single_iface;
bool phy_mac;
bool infinite_rx;
@@ -125,6 +127,7 @@ struct pmd_devargs {
struct pmd_devargs_all {
struct pmd_devargs rx_queues;
struct pmd_devargs tx_queues;
+ uint32_t snapshot_len;
bool single_iface;
bool is_tx_pcap;
bool is_tx_iface;
@@ -142,11 +145,16 @@ static const char *valid_arguments[] = {
ETH_PCAP_IFACE_ARG,
ETH_PCAP_PHY_MAC_ARG,
ETH_PCAP_INFINITE_RX_ARG,
+ ETH_PCAP_SNAPSHOT_LEN_ARG,
NULL
};

RTE_LOG_REGISTER_DEFAULT(eth_pcap_logtype, NOTICE);

+/* Forward declaration */
+static inline int set_iface_direction(const char *iface, pcap_t *pcap,
+ pcap_direction_t direction);
+
static struct queue_missed_stat*
queue_missed_stat_update(struct rte_eth_dev *dev, unsigned int qid)
{
@@ -406,25 +414,24 @@ pcap_pktmbuf_read(const struct rte_mbuf *m,
static uint16_t
eth_pcap_tx_dumper(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
{
- unsigned int i;
- struct pmd_process_private *pp;
struct pcap_tx_queue *dumper_q = queue;
- pcap_dumper_t *dumper;
+ struct rte_eth_dev *dev = &rte_eth_devices[dumper_q->port_id];
+ struct pmd_internals *internals = dev->data->dev_private;
+ struct pmd_process_private *pp = dev->process_private;
+ uint32_t snaplen = internals->snapshot_len;
+ pcap_dumper_t *dumper = pp->tx_dumper[dumper_q->queue_id];
uint16_t num_tx = 0;
uint32_t tx_bytes = 0;
struct pcap_pkthdr header;

- pp = rte_eth_devices[dumper_q->port_id].process_private;
- dumper = pp->tx_dumper[dumper_q->queue_id];
-
- if (unlikely(dumper == NULL || nb_pkts == 0))
+ if (unlikely(dumper == NULL))
return 0;

/* all packets in burst have same timestamp */
calculate_timestamp(&header.ts);

/* writes the nb_pkts packets to the previously opened pcap file dumper */
- for (i = 0; i < nb_pkts; i++) {
+ for (uint16_t i = 0; i < nb_pkts; i++) {
struct rte_mbuf *mbuf = bufs[i];

if (mbuf->ol_flags & RTE_MBUF_F_TX_VLAN) {
@@ -434,11 +441,12 @@ eth_pcap_tx_dumper(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
}

uint32_t len = rte_pktmbuf_pkt_len(mbuf);
+ uint32_t caplen = RTE_MIN(len, snaplen);
header.len = len;
- header.caplen = len;
+ header.caplen = caplen;

void *temp = NULL;
- const uint8_t *data = pcap_pktmbuf_read(mbuf, 0, len, &temp);
+ const uint8_t *data = pcap_pktmbuf_read(mbuf, 0, caplen, &temp);
if (likely(data != NULL)) {
pcap_dump((u_char *)dumper, &header, data);

@@ -537,7 +545,7 @@ eth_pcap_tx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
* pcap_open_live wrapper function
*/
static inline int
-open_iface_live(const char *iface, pcap_t **pcap)
+open_iface_live(const char *iface, pcap_t **pcap, uint32_t snaplen)
{
char errbuf[PCAP_ERRBUF_SIZE];
pcap_t *pc;
@@ -564,7 +572,7 @@ open_iface_live(const char *iface, pcap_t **pcap)
PMD_LOG(WARNING, "%s: Could not set to promiscuous: %s",
iface, pcap_statustostr(status));

- status = pcap_set_snaplen(pc, RTE_ETH_PCAP_SNAPSHOT_LEN);
+ status = pcap_set_snaplen(pc, snaplen);
if (status != 0)
PMD_LOG(WARNING, "%s: Could not set snapshot length: %s",
iface, pcap_statustostr(status));
@@ -595,9 +603,9 @@ open_iface_live(const char *iface, pcap_t **pcap)
}

static int
-open_single_iface(const char *iface, pcap_t **pcap)
+open_single_iface(const char *iface, pcap_t **pcap, uint32_t snaplen)
{
- if (open_iface_live(iface, pcap) < 0) {
+ if (open_iface_live(iface, pcap, snaplen) < 0) {
PMD_LOG(ERR, "Couldn't open interface %s", iface);
return -1;
}
@@ -606,7 +614,8 @@ open_single_iface(const char *iface, pcap_t **pcap)
}

static int
-open_single_tx_pcap(const char *pcap_filename, pcap_dumper_t **dumper)
+open_single_tx_pcap(const char *pcap_filename, pcap_dumper_t **dumper,
+ uint32_t snaplen)
{
pcap_t *tx_pcap;

@@ -616,7 +625,7 @@ open_single_tx_pcap(const char *pcap_filename, pcap_dumper_t **dumper)
* pcap holder.
*/
tx_pcap = pcap_open_dead_with_tstamp_precision(DLT_EN10MB,
- RTE_ETH_PCAP_SNAPSHOT_LEN, PCAP_TSTAMP_PRECISION_NANO);
+ snaplen, PCAP_TSTAMP_PRECISION_NANO);
if (tx_pcap == NULL) {
PMD_LOG(ERR, "Couldn't create dead pcap");
return -1;
@@ -677,6 +686,7 @@ eth_dev_start(struct rte_eth_dev *dev)
struct pmd_process_private *pp = dev->process_private;
struct pcap_tx_queue *tx;
struct pcap_rx_queue *rx;
+ uint32_t snaplen = internals->snapshot_len;

if (internals->timestamp_offloading) {
int ret = rte_mbuf_dyn_rx_timestamp_register(&timestamp_dynfield_offset,
@@ -694,7 +704,7 @@ eth_dev_start(struct rte_eth_dev *dev)

if (!pp->tx_pcap[0] &&
strcmp(tx->type, ETH_PCAP_IFACE_ARG) == 0) {
- if (open_single_iface(tx->name, &pp->tx_pcap[0]) < 0)
+ if (open_single_iface(tx->name, &pp->tx_pcap[0], snaplen) < 0)
return -1;
pp->rx_pcap[0] = pp->tx_pcap[0];
}
@@ -706,14 +716,11 @@ eth_dev_start(struct rte_eth_dev *dev)
for (i = 0; i < dev->data->nb_tx_queues; i++) {
tx = &internals->tx_queue[i];

- if (!pp->tx_dumper[i] &&
- strcmp(tx->type, ETH_PCAP_TX_PCAP_ARG) == 0) {
- if (open_single_tx_pcap(tx->name,
- &pp->tx_dumper[i]) < 0)
+ if (!pp->tx_dumper[i] && strcmp(tx->type, ETH_PCAP_TX_PCAP_ARG) == 0) {
+ if (open_single_tx_pcap(tx->name, &pp->tx_dumper[i], snaplen) < 0)
return -1;
- } else if (!pp->tx_pcap[i] &&
- strcmp(tx->type, ETH_PCAP_TX_IFACE_ARG) == 0) {
- if (open_single_iface(tx->name, &pp->tx_pcap[i]) < 0)
+ } else if (!pp->tx_pcap[i] && strcmp(tx->type, ETH_PCAP_TX_IFACE_ARG) == 0) {
+ if (open_single_iface(tx->name, &pp->tx_pcap[i], snaplen) < 0)
return -1;
}
}
@@ -728,9 +735,14 @@ eth_dev_start(struct rte_eth_dev *dev)
if (strcmp(rx->type, ETH_PCAP_RX_PCAP_ARG) == 0) {
if (open_single_rx_pcap(rx->name, &pp->rx_pcap[i]) < 0)
return -1;
- } else if (strcmp(rx->type, ETH_PCAP_RX_IFACE_ARG) == 0) {
- if (open_single_iface(rx->name, &pp->rx_pcap[i]) < 0)
+ } else if (strcmp(rx->type, ETH_PCAP_RX_IFACE_ARG) == 0 ||
+ strcmp(rx->type, ETH_PCAP_RX_IFACE_IN_ARG) == 0) {
+ if (open_single_iface(rx->name, &pp->rx_pcap[i], snaplen) < 0)
return -1;
+ /* Set direction for rx_iface_in */
+ if (strcmp(rx->type, ETH_PCAP_RX_IFACE_IN_ARG) == 0)
+ set_iface_direction(rx->name, pp->rx_pcap[i],
+ PCAP_D_IN);
}
}

@@ -821,11 +833,11 @@ eth_dev_info(struct rte_eth_dev *dev,

dev_info->if_index = internals->if_index;
dev_info->max_mac_addrs = 1;
- dev_info->max_rx_pktlen = RTE_ETH_PCAP_SNAPSHOT_LEN;
+ dev_info->max_rx_pktlen = internals->snapshot_len;
dev_info->max_rx_queues = dev->data->nb_rx_queues;
dev_info->max_tx_queues = dev->data->nb_tx_queues;
- dev_info->min_rx_bufsize = 0;
- dev_info->max_mtu = RTE_ETH_PCAP_SNAPSHOT_LEN - RTE_ETHER_HDR_LEN;
+ dev_info->min_rx_bufsize = RTE_ETHER_MIN_LEN;
+ dev_info->max_mtu = internals->snapshot_len - RTE_ETHER_HDR_LEN;
dev_info->tx_offload_capa = RTE_ETH_TX_OFFLOAD_MULTI_SEGS |
RTE_ETH_TX_OFFLOAD_VLAN_INSERT;
dev_info->rx_offload_capa = RTE_ETH_RX_OFFLOAD_VLAN_STRIP |
@@ -1242,41 +1254,32 @@ open_rx_pcap(const char *key, const char *value, void *extra_args)
}

/*
- * Opens a pcap file for writing and stores a reference to it
- * for use it later on.
+ * Store TX pcap file configuration.
+ * The actual pcap dumper is opened in eth_dev_start().
*/
static int
open_tx_pcap(const char *key, const char *value, void *extra_args)
{
const char *pcap_filename = value;
struct pmd_devargs *dumpers = extra_args;
- pcap_dumper_t *dumper;
-
- if (open_single_tx_pcap(pcap_filename, &dumper) < 0)
- return -1;

- if (add_queue(dumpers, pcap_filename, key, NULL, dumper) < 0) {
- pcap_dump_close(dumper);
+ if (add_queue(dumpers, pcap_filename, key, NULL, NULL) < 0)
return -1;
- }

return 0;
}

/*
- * Opens an interface for reading and writing
+ * Store interface configuration for reading and writing.
+ * The actual pcap handle is opened in eth_dev_start().
*/
static inline int
open_rx_tx_iface(const char *key, const char *value, void *extra_args)
{
const char *iface = value;
struct pmd_devargs *tx = extra_args;
- pcap_t *pcap = NULL;

- if (open_single_iface(iface, &pcap) < 0)
- return -1;
-
- tx->queue[0].pcap = pcap;
+ tx->queue[0].pcap = NULL;
tx->queue[0].name = iface;
tx->queue[0].type = key;

@@ -1298,42 +1301,30 @@ set_iface_direction(const char *iface, pcap_t *pcap,
return 0;
}

+/*
+ * Store interface configuration.
+ * The actual pcap handle is opened in eth_dev_start().
+ */
static inline int
open_iface(const char *key, const char *value, void *extra_args)
{
const char *iface = value;
struct pmd_devargs *pmd = extra_args;
- pcap_t *pcap = NULL;

- if (open_single_iface(iface, &pcap) < 0)
- return -1;
- if (add_queue(pmd, iface, key, pcap, NULL) < 0) {
- pcap_close(pcap);
+ if (add_queue(pmd, iface, key, NULL, NULL) < 0)
return -1;
- }

return 0;
}

/*
- * Opens a NIC for reading packets from it
+ * Store RX interface configuration.
+ * The actual pcap handle is opened and direction set in eth_dev_start().
*/
static inline int
open_rx_iface(const char *key, const char *value, void *extra_args)
{
- int ret = open_iface(key, value, extra_args);
- if (ret < 0)
- return ret;
- if (strcmp(key, ETH_PCAP_RX_IFACE_IN_ARG) == 0) {
- struct pmd_devargs *pmd = extra_args;
- unsigned int qid = pmd->num_of_queue - 1;
-
- set_iface_direction(pmd->queue[qid].name,
- pmd->queue[qid].pcap,
- PCAP_D_IN);
- }
-
- return 0;
+ return open_iface(key, value, extra_args);
}

static inline int
@@ -1373,6 +1364,29 @@ process_bool_flag(const char *key, const char *value, void *extra_args)
return 0;
}

+static int
+process_snapshot_len(const char *key, const char *value, void *extra_args)
+{
+ uint32_t *snaplen = extra_args;
+ unsigned long val;
+ char *endptr;
+
+ if (value == NULL || *value == '\0') {
+ PMD_LOG(ERR, "Argument '%s' requires a value", key);
+ return -1;
+ }
+
+ errno = 0;
+ val = strtoul(value, &endptr, 10);
+ if (errno != 0 || *endptr != '\0' || val == 0 || val > UINT32_MAX) {
+ PMD_LOG(ERR, "Invalid '%s' value '%s'", key, value);
+ return -1;
+ }
+
+ *snaplen = (uint32_t)val;
+ return 0;
+}
+
static int
pmd_init_internals(struct rte_vdev_device *vdev,
const unsigned int nb_rx_queues,
@@ -1537,6 +1551,8 @@ eth_from_pcaps(struct rte_vdev_device *vdev,
}

internals->infinite_rx = infinite_rx;
+ internals->snapshot_len = devargs_all->snapshot_len;
+
/* Assign rx ops. */
if (infinite_rx)
eth_dev->rx_pkt_burst = eth_pcap_rx_infinite;
@@ -1597,6 +1613,7 @@ pmd_pcap_probe(struct rte_vdev_device *dev)
int ret = 0;

struct pmd_devargs_all devargs_all = {
+ .snapshot_len = ETH_PCAP_SNAPSHOT_LEN_DEFAULT,
.single_iface = 0,
.is_tx_pcap = 0,
.is_tx_iface = 0,
@@ -1632,6 +1649,17 @@ pmd_pcap_probe(struct rte_vdev_device *dev)
return -1;
}

+ /*
+ * Process optional snapshot length argument.
+ */
+ if (rte_kvargs_count(kvlist, ETH_PCAP_SNAPSHOT_LEN_ARG) == 1) {
+ ret = rte_kvargs_process(kvlist, ETH_PCAP_SNAPSHOT_LEN_ARG,
+ &process_snapshot_len,
+ &devargs_all.snapshot_len);
+ if (ret < 0)
+ goto free_kvlist;
+ }
+
/*
* If iface argument is passed we open the NICs and use them for
* reading / writing
@@ -1837,5 +1865,6 @@ RTE_PMD_REGISTER_PARAM_STRING(net_pcap,
ETH_PCAP_RX_IFACE_IN_ARG "=<ifc> "
ETH_PCAP_TX_IFACE_ARG "=<ifc> "
ETH_PCAP_IFACE_ARG "=<ifc> "
- ETH_PCAP_PHY_MAC_ARG "=<int>"
- ETH_PCAP_INFINITE_RX_ARG "=<0|1>");
+ ETH_PCAP_PHY_MAC_ARG "=<int> "
+ ETH_PCAP_INFINITE_RX_ARG "=<0|1> "
+ ETH_PCAP_SNAPSHOT_LEN_ARG "=<int>");
--
2.51.0