pcap: fix double stop error

librte_pmd_pcap driver was opening the pcap/interfaces only at init time and
closing them only when the port was being stopped. This behaviour would cause
problems (leading to segfault) if the user closed the port 2 times. The first
time the pcap/interfaces would be normally closed but libpcap would throw an
error causing a segfault if the closed pcaps/interfaces were closed again.
This behaviour is solved by re-openning pcaps/interfaces when the port is
started (only if these weren't open already for example at init time).

Signed-off-by: Nicolás Pernas Maradei <nico@emutex.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>

diff --git a/lib/librte_pmd_pcap/rte_eth_pcap.c b/lib/librte_pmd_pcap/rte_eth_pcap.c
index 19492e8..f12d1e7 100644 (file)
--- a/lib/librte_pmd_pcap/rte_eth_pcap.c
+++ b/lib/librte_pmd_pcap/rte_eth_pcap.c
@@ -67,6 +67,8 @@ struct pcap_rx_queue {
        struct rte_mempool *mb_pool;
        volatile unsigned long rx_pkts;
        volatile unsigned long err_pkts;
+       const char *name;
+       const char *type;
 };
 
 struct pcap_tx_queue {
@@ -74,27 +76,32 @@ struct pcap_tx_queue {
        pcap_t *pcap;
        volatile unsigned long tx_pkts;
        volatile unsigned long err_pkts;
+       const char *name;
+       const char *type;
 };
 
 struct rx_pcaps {
        unsigned num_of_rx;
        pcap_t *pcaps[RTE_PMD_RING_MAX_RX_RINGS];
+       const char *names[RTE_PMD_RING_MAX_RX_RINGS];
+       const char *types[RTE_PMD_RING_MAX_RX_RINGS];
 };
 
 struct tx_pcaps {
        unsigned num_of_tx;
        pcap_dumper_t *dumpers[RTE_PMD_RING_MAX_TX_RINGS];
        pcap_t *pcaps[RTE_PMD_RING_MAX_RX_RINGS];
+       const char *names[RTE_PMD_RING_MAX_RX_RINGS];
+       const char *types[RTE_PMD_RING_MAX_RX_RINGS];
 };
 
 struct pmd_internals {
+       struct pcap_rx_queue rx_queue[RTE_PMD_RING_MAX_RX_RINGS];
+       struct pcap_tx_queue tx_queue[RTE_PMD_RING_MAX_TX_RINGS];
        unsigned nb_rx_queues;
        unsigned nb_tx_queues;
-
        int if_index;
-
-       struct pcap_rx_queue rx_queue[RTE_PMD_RING_MAX_RX_RINGS];
-       struct pcap_tx_queue tx_queue[RTE_PMD_RING_MAX_TX_RINGS];
+       int single_iface;
 };
 
 const char *valid_arguments[] = {
@@ -106,6 +113,10 @@ const char *valid_arguments[] = {
        NULL
 };
 
+static int open_single_tx_pcap(const char *pcap_filename, pcap_dumper_t **dumper);
+static int open_single_rx_pcap(const char *pcap_filename, pcap_t **pcap);
+static int open_single_iface(const char *iface, pcap_t **pcap);
+
 static struct ether_addr eth_addr = { .addr_bytes = { 0, 0, 0, 0x1, 0x2, 0x3 } };
 static const char *drivername = "Pcap PMD";
 static struct rte_eth_link pmd_link = {
@@ -258,6 +269,59 @@ eth_pcap_tx(void *queue,
 static int
 eth_dev_start(struct rte_eth_dev *dev)
 {
+       unsigned i;
+       struct pmd_internals *internals = dev->data->dev_private;
+       struct pcap_tx_queue *tx;
+       struct pcap_rx_queue *rx;
+
+       /* Special iface case. Single pcap is open and shared between tx/rx. */
+       if (internals->single_iface) {
+               tx = &internals->tx_queue[0];
+               rx = &internals->rx_queue[0];
+
+               if (!tx->pcap && strcmp(tx->type, ETH_PCAP_IFACE_ARG) == 0) {
+                       if (open_single_iface(tx->name, &tx->pcap) < 0)
+                               return -1;
+                       rx->pcap = tx->pcap;
+               }
+               goto status_up;
+       }
+
+       /* If not open already, open tx pcaps/dumpers */
+       for (i = 0; i < internals->nb_tx_queues; i++) {
+               tx = &internals->tx_queue[i];
+
+               if (!tx->dumper && strcmp(tx->type, ETH_PCAP_TX_PCAP_ARG) == 0) {
+                       if (open_single_tx_pcap(tx->name, &tx->dumper) < 0)
+                               return -1;
+               }
+
+               else if (!tx->pcap && strcmp(tx->type, ETH_PCAP_TX_IFACE_ARG) == 0) {
+                       if (open_single_iface(tx->name, &tx->pcap) < 0)
+                               return -1;
+               }
+       }
+
+       /* If not open already, open rx pcaps */
+       for (i = 0; i < internals->nb_rx_queues; i++) {
+               rx = &internals->rx_queue[i];
+
+               if (rx->pcap != NULL)
+                       continue;
+
+               if (strcmp(rx->type, ETH_PCAP_RX_PCAP_ARG) == 0) {
+                       if (open_single_rx_pcap(rx->name, &rx->pcap) < 0)
+                               return -1;
+               }
+
+               else if (strcmp(rx->type, ETH_PCAP_RX_IFACE_ARG) == 0) {
+                       if (open_single_iface(rx->name, &rx->pcap) < 0)
+                               return -1;
+               }
+       }
+
+status_up:
+
        dev->data->dev_link.link_status = 1;
        return 0;
 }
@@ -271,19 +335,44 @@ static void
 eth_dev_stop(struct rte_eth_dev *dev)
 {
        unsigned i;
-       pcap_dumper_t *dumper;
-       pcap_t *pcap;
        struct pmd_internals *internals = dev->data->dev_private;
+       struct pcap_tx_queue *tx;
+       struct pcap_rx_queue *rx;
+
+       /* Special iface case. Single pcap is open and shared between tx/rx. */
+       if (internals->single_iface) {
+               tx = &internals->tx_queue[0];
+               rx = &internals->rx_queue[0];
+               pcap_close(tx->pcap);
+               tx->pcap = NULL;
+               rx->pcap = NULL;
+               goto status_down;
+       }
 
        for (i = 0; i < internals->nb_tx_queues; i++) {
-               dumper = internals->tx_queue[i].dumper;
-               if(dumper != NULL)
-                       pcap_dump_close(dumper);
-               pcap = internals->tx_queue[i].pcap;
-               if(pcap != NULL)
-                       pcap_close(pcap);
+               tx = &internals->tx_queue[i];
+
+               if (tx->dumper != NULL) {
+                       pcap_dump_close(tx->dumper);
+                       tx->dumper = NULL;
+               }
+
+               if (tx->pcap != NULL) {
+                       pcap_close(tx->pcap);
+                       tx->pcap = NULL;
+               }
+       }
+
+       for (i = 0; i < internals->nb_rx_queues; i++) {
+               rx = &internals->rx_queue[i];
+
+               if (rx->pcap != NULL) {
+                       pcap_close(rx->pcap);
+                       rx->pcap = NULL;
+               }
        }
 
+status_down:
        dev->data->dev_link.link_status = 0;
 }
 
@@ -415,55 +504,79 @@ static struct eth_dev_ops ops = {
  * reference of it for use it later on.
  */
 static int
-open_rx_pcap(const char *key __rte_unused, const char *value, void *extra_args)
+open_rx_pcap(const char *key, const char *value, void *extra_args)
 {
        unsigned i;
        const char *pcap_filename = value;
        struct rx_pcaps *pcaps = extra_args;
-       pcap_t *rx_pcap;
+       pcap_t *pcap = NULL;
 
        for (i = 0; i < pcaps->num_of_rx; i++) {
-               if ((rx_pcap = pcap_open_offline(pcap_filename, errbuf)) == NULL) {
-                       RTE_LOG(ERR, PMD, "Couldn't open %s: %s\n", pcap_filename, errbuf);
+               if (open_single_rx_pcap(pcap_filename, &pcap) < 0)
                        return -1;
-               }
-               pcaps->pcaps[i] = rx_pcap;
+
+               pcaps->pcaps[i] = pcap;
+               pcaps->names[i] = pcap_filename;
+               pcaps->types[i] = key;
        }
 
        return 0;
 }
 
+static int
+open_single_rx_pcap(const char *pcap_filename, pcap_t **pcap)
+{
+       if ((*pcap = pcap_open_offline(pcap_filename, errbuf)) == NULL) {
+               RTE_LOG(ERR, PMD, "Couldn't open %s: %s\n", pcap_filename, errbuf);
+               return -1;
+       }
+       return 0;
+}
+
 /*
  * Opens a pcap file for writing and stores a reference to it
  * for use it later on.
  */
 static int
-open_tx_pcap(const char *key __rte_unused, const char *value, void *extra_args)
+open_tx_pcap(const char *key, const char *value, void *extra_args)
 {
        unsigned i;
        const char *pcap_filename = value;
        struct tx_pcaps *dumpers = extra_args;
-       pcap_t *tx_pcap;
        pcap_dumper_t *dumper;
 
        for (i = 0; i < dumpers->num_of_tx; i++) {
-               /*
-                * We need to create a dummy empty pcap_t to use it
-                * with pcap_dump_open(). We create big enough an Ethernet
-                * pcap holder.
-                */
-               if ((tx_pcap = pcap_open_dead(DLT_EN10MB, RTE_ETH_PCAP_SNAPSHOT_LEN))
-                               == NULL) {
-                       RTE_LOG(ERR, PMD, "Couldn't create dead pcap\n");
+               if (open_single_tx_pcap(pcap_filename, &dumper) < 0)
                        return -1;
-               }
 
-               /* The dumper is created using the previous pcap_t reference */
-               if ((dumper = pcap_dump_open(tx_pcap, pcap_filename)) == NULL) {
-                       RTE_LOG(ERR, PMD, "Couldn't open %s for writing.\n", pcap_filename);
-                       return -1;
-               }
                dumpers->dumpers[i] = dumper;
+               dumpers->names[i] = pcap_filename;
+               dumpers->types[i] = key;
+       }
+
+       return 0;
+}
+
+static int
+open_single_tx_pcap(const char *pcap_filename, pcap_dumper_t **dumper)
+{
+       pcap_t *tx_pcap;
+       /*
+        * We need to create a dummy empty pcap_t to use it
+        * with pcap_dump_open(). We create big enough an Ethernet
+        * pcap holder.
+        */
+
+       if ((tx_pcap = pcap_open_dead(DLT_EN10MB, RTE_ETH_PCAP_SNAPSHOT_LEN))
+                       == NULL) {
+               RTE_LOG(ERR, PMD, "Couldn't create dead pcap\n");
+               return -1;
+       }
+
+       /* The dumper is created using the previous pcap_t reference */
+       if ((*dumper = pcap_dump_open(tx_pcap, pcap_filename)) == NULL) {
+               RTE_LOG(ERR, PMD, "Couldn't open %s for writing.\n", pcap_filename);
+               return -1;
        }
 
        return 0;
@@ -488,13 +601,19 @@ open_iface_live(const char *iface, pcap_t **pcap) {
  * Opens an interface for reading and writing
  */
 static inline int
-open_rx_tx_iface(const char *key __rte_unused, const char *value, void *extra_args)
+open_rx_tx_iface(const char *key, const char *value, void *extra_args)
 {
        const char *iface = value;
-       pcap_t **pcap = extra_args;
+       struct rx_pcaps *pcaps = extra_args;
+       pcap_t *pcap = NULL;
 
-       if(open_iface_live(iface, pcap) < 0)
+       if (open_single_iface(iface, &pcap) < 0)
                return -1;
+
+       pcaps->pcaps[0] = pcap;
+       pcaps->names[0] = iface;
+       pcaps->types[0] = key;
+
        return 0;
 }
 
@@ -502,7 +621,7 @@ open_rx_tx_iface(const char *key __rte_unused, const char *value, void *extra_ar
  * Opens a NIC for reading packets from it
  */
 static inline int
-open_rx_iface(const char *key __rte_unused, const char *value, void *extra_args)
+open_rx_iface(const char *key, const char *value, void *extra_args)
 {
        unsigned i;
        const char *iface = value;
@@ -510,9 +629,11 @@ open_rx_iface(const char *key __rte_unused, const char *value, void *extra_args)
        pcap_t *pcap = NULL;
 
        for (i = 0; i < pcaps->num_of_rx; i++) {
-               if(open_iface_live(iface, &pcap) < 0)
+               if (open_single_iface(iface, &pcap) < 0)
                        return -1;
                pcaps->pcaps[i] = pcap;
+               pcaps->names[i] = iface;
+               pcaps->types[i] = key;
        }
 
        return 0;
@@ -521,8 +642,8 @@ open_rx_iface(const char *key __rte_unused, const char *value, void *extra_args)
 /*
  * Opens a NIC for writing packets to it
  */
-static inline int
-open_tx_iface(const char *key __rte_unused, const char *value, void *extra_args)
+static int
+open_tx_iface(const char *key, const char *value, void *extra_args)
 {
        unsigned i;
        const char *iface = value;
@@ -530,14 +651,26 @@ open_tx_iface(const char *key __rte_unused, const char *value, void *extra_args)
        pcap_t *pcap;
 
        for (i = 0; i < pcaps->num_of_tx; i++) {
-               if(open_iface_live(iface, &pcap) < 0)
+               if (open_single_iface(iface, &pcap) < 0)
                        return -1;
                pcaps->pcaps[i] = pcap;
+               pcaps->names[i] = iface;
+               pcaps->types[i] = key;
        }
 
        return 0;
 }
 
+static int
+open_single_iface(const char *iface, pcap_t **pcap)
+{
+       if (open_iface_live(iface, pcap) < 0) {
+               RTE_LOG(ERR, PMD, "Couldn't open interface %s\n", iface);
+               return -1;
+       }
+
+       return 0;
+}
 
 static int
 rte_pmd_init_internals(const char *name, const unsigned nb_rx_queues,
@@ -623,9 +756,10 @@ rte_pmd_init_internals(const char *name, const unsigned nb_rx_queues,
 }
 
 static int
-rte_eth_from_pcaps_n_dumpers(const char *name, pcap_t * const rx_queues[],
+rte_eth_from_pcaps_n_dumpers(const char *name,
+               struct rx_pcaps *rx_queues,
                const unsigned nb_rx_queues,
-               pcap_dumper_t * const tx_queues[],
+               struct tx_pcaps *tx_queues,
                const unsigned nb_tx_queues,
                const unsigned numa_node,
                struct rte_kvargs *kvlist)
@@ -645,25 +779,35 @@ rte_eth_from_pcaps_n_dumpers(const char *name, pcap_t * const rx_queues[],
                return -1;
 
        for (i = 0; i < nb_rx_queues; i++) {
-               internals->rx_queue->pcap = rx_queues[i];
+               internals->rx_queue->pcap = rx_queues->pcaps[i];
+               internals->rx_queue->name = rx_queues->names[i];
+               internals->rx_queue->type = rx_queues->types[i];
        }
        for (i = 0; i < nb_tx_queues; i++) {
-               internals->tx_queue->dumper = tx_queues[i];
+               internals->tx_queue->dumper = tx_queues->dumpers[i];
+               internals->tx_queue->name = tx_queues->names[i];
+               internals->tx_queue->type = tx_queues->types[i];
        }
 
+       /* using multiple pcaps/interfaces */
+       internals->single_iface = 0;
+
        eth_dev->rx_pkt_burst = eth_pcap_rx;
        eth_dev->tx_pkt_burst = eth_pcap_tx_dumper;
 
        return 0;
 }
 
+       struct rx_pcaps pcaps;
 static int
-rte_eth_from_pcaps(const char *name, pcap_t * const rx_queues[],
+rte_eth_from_pcaps(const char *name,
+               struct rx_pcaps *rx_queues,
                const unsigned nb_rx_queues,
-               pcap_t * const tx_queues[],
+               struct tx_pcaps *tx_queues,
                const unsigned nb_tx_queues,
                const unsigned numa_node,
-               struct rte_kvargs *kvlist)
+               struct rte_kvargs *kvlist,
+               int single_iface)
 {
        struct pmd_internals *internals = NULL;
        struct rte_eth_dev *eth_dev = NULL;
@@ -680,12 +824,19 @@ rte_eth_from_pcaps(const char *name, pcap_t * const rx_queues[],
                return -1;
 
        for (i = 0; i < nb_rx_queues; i++) {
-               internals->rx_queue->pcap = rx_queues[i];
+               internals->rx_queue->pcap = rx_queues->pcaps[i];
+               internals->rx_queue->name = rx_queues->names[i];
+               internals->rx_queue->type = rx_queues->types[i];
        }
        for (i = 0; i < nb_tx_queues; i++) {
-               internals->tx_queue->pcap = tx_queues[i];
+               internals->tx_queue->pcap = tx_queues->pcaps[i];
+               internals->tx_queue->name = tx_queues->names[i];
+               internals->tx_queue->type = tx_queues->types[i];
        }
 
+       /* store wether we are using a single interface for rx/tx or not */
+       internals->single_iface = single_iface;
+
        eth_dev->rx_pkt_burst = eth_pcap_rx;
        eth_dev->tx_pkt_burst = eth_pcap_tx;
 
@@ -721,12 +872,14 @@ rte_pmd_pcap_devinit(const char *name, const char *params)
        if (rte_kvargs_count(kvlist, ETH_PCAP_IFACE_ARG) == 1) {
 
                ret = rte_kvargs_process(kvlist, ETH_PCAP_IFACE_ARG,
-                               &open_rx_tx_iface, &pcaps.pcaps[0]);
+                               &open_rx_tx_iface, &pcaps);
                if (ret < 0)
                        return -1;
-
-               return rte_eth_from_pcaps(name, pcaps.pcaps, 1, pcaps.pcaps, 1,
-                               numa_node, kvlist);
+               dumpers.pcaps[0] = pcaps.pcaps[0];
+               dumpers.names[0] = pcaps.names[0];
+               dumpers.types[0] = pcaps.types[0];
+               return rte_eth_from_pcaps(name, &pcaps, 1, &dumpers, 1,
+                               numa_node, kvlist, 1);
        }
 
        /*
@@ -766,11 +919,11 @@ rte_pmd_pcap_devinit(const char *name, const char *params)
                return -1;
 
        if (using_dumpers)
-               return rte_eth_from_pcaps_n_dumpers(name, pcaps.pcaps, pcaps.num_of_rx,
-                               dumpers.dumpers, dumpers.num_of_tx, numa_node, kvlist);
+               return rte_eth_from_pcaps_n_dumpers(name, &pcaps, pcaps.num_of_rx,
+                               &dumpers, dumpers.num_of_tx, numa_node, kvlist);
 
-       return rte_eth_from_pcaps(name, pcaps.pcaps, pcaps.num_of_rx, dumpers.pcaps,
-                       dumpers.num_of_tx, numa_node, kvlist);
+       return rte_eth_from_pcaps(name, &pcaps, pcaps.num_of_rx, &dumpers,
+                       dumpers.num_of_tx, numa_node, kvlist, 0);
 
 }