freebsd-dev/sys/dev/netmap/netmap_pipe.c
2018-05-18 03:38:17 +00:00

820 lines
21 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (C) 2014-2016 Giuseppe Lettieri
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/* $FreeBSD$ */
#if defined(__FreeBSD__)
#include <sys/cdefs.h> /* prerequisite */
#include <sys/types.h>
#include <sys/errno.h>
#include <sys/param.h> /* defines used in kernel.h */
#include <sys/kernel.h> /* types used in module initialization */
#include <sys/malloc.h>
#include <sys/poll.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#include <sys/selinfo.h>
#include <sys/sysctl.h>
#include <sys/socket.h> /* sockaddrs */
#include <net/if.h>
#include <net/if_var.h>
#include <machine/bus.h> /* bus_dmamap_* */
#include <sys/refcount.h>
#elif defined(linux)
#include "bsd_glue.h"
#elif defined(__APPLE__)
#warning OSX support is only partial
#include "osx_glue.h"
#elif defined(_WIN32)
#include "win_glue.h"
#else
#error Unsupported platform
#endif /* unsupported */
/*
* common headers
*/
#include <net/netmap.h>
#include <dev/netmap/netmap_kern.h>
#include <dev/netmap/netmap_mem2.h>
#ifdef WITH_PIPES
#define NM_PIPE_MAXSLOTS 4096
#define NM_PIPE_MAXRINGS 256
static int netmap_default_pipes = 0; /* ignored, kept for compatibility */
SYSBEGIN(vars_pipes);
SYSCTL_DECL(_dev_netmap);
SYSCTL_INT(_dev_netmap, OID_AUTO, default_pipes, CTLFLAG_RW,
&netmap_default_pipes, 0, "For compatibility only");
SYSEND;
/* allocate the pipe array in the parent adapter */
static int
nm_pipe_alloc(struct netmap_adapter *na, u_int npipes)
{
size_t old_len, len;
struct netmap_pipe_adapter **npa;
if (npipes <= na->na_max_pipes)
/* we already have more entries that requested */
return 0;
if (npipes < na->na_next_pipe || npipes > NM_MAXPIPES)
return EINVAL;
old_len = sizeof(struct netmap_pipe_adapter *)*na->na_max_pipes;
len = sizeof(struct netmap_pipe_adapter *) * npipes;
npa = nm_os_realloc(na->na_pipes, len, old_len);
if (npa == NULL)
return ENOMEM;
na->na_pipes = npa;
na->na_max_pipes = npipes;
return 0;
}
/* deallocate the parent array in the parent adapter */
void
netmap_pipe_dealloc(struct netmap_adapter *na)
{
if (na->na_pipes) {
if (na->na_next_pipe > 0) {
D("freeing not empty pipe array for %s (%d dangling pipes)!", na->name,
na->na_next_pipe);
}
nm_os_free(na->na_pipes);
na->na_pipes = NULL;
na->na_max_pipes = 0;
na->na_next_pipe = 0;
}
}
/* find a pipe endpoint with the given id among the parent's pipes */
static struct netmap_pipe_adapter *
netmap_pipe_find(struct netmap_adapter *parent, const char *pipe_id)
{
int i;
struct netmap_pipe_adapter *na;
for (i = 0; i < parent->na_next_pipe; i++) {
const char *na_pipe_id;
na = parent->na_pipes[i];
na_pipe_id = strrchr(na->up.name,
na->role == NM_PIPE_ROLE_MASTER ? '{' : '}');
KASSERT(na_pipe_id != NULL, ("Invalid pipe name"));
++na_pipe_id;
if (!strcmp(na_pipe_id, pipe_id)) {
return na;
}
}
return NULL;
}
/* add a new pipe endpoint to the parent array */
static int
netmap_pipe_add(struct netmap_adapter *parent, struct netmap_pipe_adapter *na)
{
if (parent->na_next_pipe >= parent->na_max_pipes) {
u_int npipes = parent->na_max_pipes ? 2*parent->na_max_pipes : 2;
int error = nm_pipe_alloc(parent, npipes);
if (error)
return error;
}
parent->na_pipes[parent->na_next_pipe] = na;
na->parent_slot = parent->na_next_pipe;
parent->na_next_pipe++;
return 0;
}
/* remove the given pipe endpoint from the parent array */
static void
netmap_pipe_remove(struct netmap_adapter *parent, struct netmap_pipe_adapter *na)
{
u_int n;
n = --parent->na_next_pipe;
if (n != na->parent_slot) {
struct netmap_pipe_adapter **p =
&parent->na_pipes[na->parent_slot];
*p = parent->na_pipes[n];
(*p)->parent_slot = na->parent_slot;
}
parent->na_pipes[n] = NULL;
}
int
netmap_pipe_txsync(struct netmap_kring *txkring, int flags)
{
struct netmap_kring *rxkring = txkring->pipe;
u_int k, lim = txkring->nkr_num_slots - 1;
int m; /* slots to transfer */
struct netmap_ring *txring = txkring->ring, *rxring = rxkring->ring;
ND("%p: %s %x -> %s", txkring, txkring->name, flags, rxkring->name);
ND(20, "TX before: hwcur %d hwtail %d cur %d head %d tail %d",
txkring->nr_hwcur, txkring->nr_hwtail,
txkring->rcur, txkring->rhead, txkring->rtail);
m = txkring->rhead - txkring->nr_hwcur; /* new slots */
if (m < 0)
m += txkring->nkr_num_slots;
if (m == 0) {
/* nothing to send */
return 0;
}
for (k = txkring->nr_hwcur; m; m--, k = nm_next(k, lim)) {
struct netmap_slot *rs = &rxring->slot[k];
struct netmap_slot *ts = &txring->slot[k];
rs->len = ts->len;
rs->ptr = ts->ptr;
if (ts->flags & NS_BUF_CHANGED) {
rs->buf_idx = ts->buf_idx;
rs->flags |= NS_BUF_CHANGED;
ts->flags &= ~NS_BUF_CHANGED;
}
}
mb(); /* make sure the slots are updated before publishing them */
rxkring->nr_hwtail = k;
txkring->nr_hwcur = k;
ND(20, "TX after : hwcur %d hwtail %d cur %d head %d tail %d k %d",
txkring->nr_hwcur, txkring->nr_hwtail,
txkring->rcur, txkring->rhead, txkring->rtail, k);
rxkring->nm_notify(rxkring, 0);
return 0;
}
int
netmap_pipe_rxsync(struct netmap_kring *rxkring, int flags)
{
struct netmap_kring *txkring = rxkring->pipe;
u_int k, lim = rxkring->nkr_num_slots - 1;
int m; /* slots to release */
struct netmap_ring *txring = txkring->ring, *rxring = rxkring->ring;
ND("%p: %s %x -> %s", txkring, txkring->name, flags, rxkring->name);
ND(20, "RX before: hwcur %d hwtail %d cur %d head %d tail %d",
rxkring->nr_hwcur, rxkring->nr_hwtail,
rxkring->rcur, rxkring->rhead, rxkring->rtail);
m = rxkring->rhead - rxkring->nr_hwcur; /* released slots */
if (m < 0)
m += rxkring->nkr_num_slots;
if (m == 0) {
/* nothing to release */
return 0;
}
for (k = rxkring->nr_hwcur; m; m--, k = nm_next(k, lim)) {
struct netmap_slot *rs = &rxring->slot[k];
struct netmap_slot *ts = &txring->slot[k];
if (rs->flags & NS_BUF_CHANGED) {
/* copy the slot and report the buffer change */
*ts = *rs;
rs->flags &= ~NS_BUF_CHANGED;
}
}
mb(); /* make sure the slots are updated before publishing them */
txkring->nr_hwtail = nm_prev(k, lim);
rxkring->nr_hwcur = k;
ND(20, "RX after : hwcur %d hwtail %d cur %d head %d tail %d k %d",
rxkring->nr_hwcur, rxkring->nr_hwtail,
rxkring->rcur, rxkring->rhead, rxkring->rtail, k);
txkring->nm_notify(txkring, 0);
return 0;
}
/* Pipe endpoints are created and destroyed together, so that endopoints do not
* have to check for the existence of their peer at each ?xsync.
*
* To play well with the existing netmap infrastructure (refcounts etc.), we
* adopt the following strategy:
*
* 1) The first endpoint that is created also creates the other endpoint and
* grabs a reference to it.
*
* state A) user1 --> endpoint1 --> endpoint2
*
* 2) If, starting from state A, endpoint2 is then registered, endpoint1 gives
* its reference to the user:
*
* state B) user1 --> endpoint1 endpoint2 <--- user2
*
* 3) Assume that, starting from state B endpoint2 is closed. In the unregister
* callback endpoint2 notes that endpoint1 is still active and adds a reference
* from endpoint1 to itself. When user2 then releases her own reference,
* endpoint2 is not destroyed and we are back to state A. A symmetrical state
* would be reached if endpoint1 were released instead.
*
* 4) If, starting from state A, endpoint1 is closed, the destructor notes that
* it owns a reference to endpoint2 and releases it.
*
* Something similar goes on for the creation and destruction of the krings.
*/
/* netmap_pipe_krings_create.
*
* There are two cases:
*
* 1) state is
*
* usr1 --> e1 --> e2
*
* and we are e1. We have to create both sets
* of krings.
*
* 2) state is
*
* usr1 --> e1 --> e2
*
* and we are e2. e1 is certainly registered and our
* krings already exist. Nothing to do.
*/
static int
netmap_pipe_krings_create(struct netmap_adapter *na)
{
struct netmap_pipe_adapter *pna =
(struct netmap_pipe_adapter *)na;
struct netmap_adapter *ona = &pna->peer->up;
int error = 0;
enum txrx t;
if (pna->peer_ref) {
int i;
/* case 1) above */
ND("%p: case 1, create both ends", na);
error = netmap_krings_create(na, 0);
if (error)
goto err;
/* create the krings of the other end */
error = netmap_krings_create(ona, 0);
if (error)
goto del_krings1;
/* cross link the krings */
for_rx_tx(t) {
enum txrx r = nm_txrx_swap(t); /* swap NR_TX <-> NR_RX */
for (i = 0; i < nma_get_nrings(na, t); i++) {
NMR(na, t)[i]->pipe = NMR(ona, r)[i];
NMR(ona, r)[i]->pipe = NMR(na, t)[i];
/* mark all peer-adapter rings as fake */
NMR(ona, r)[i]->nr_kflags |= NKR_FAKERING;
}
}
}
return 0;
del_krings1:
netmap_krings_delete(na);
err:
return error;
}
/* netmap_pipe_reg.
*
* There are two cases on registration (onoff==1)
*
* 1.a) state is
*
* usr1 --> e1 --> e2
*
* and we are e1. Create the needed rings of the
* other end.
*
* 1.b) state is
*
* usr1 --> e1 --> e2 <-- usr2
*
* and we are e2. Drop the ref e1 is holding.
*
* There are two additional cases on unregister (onoff==0)
*
* 2.a) state is
*
* usr1 --> e1 --> e2
*
* and we are e1. Nothing special to do, e2 will
* be cleaned up by the destructor of e1.
*
* 2.b) state is
*
* usr1 --> e1 e2 <-- usr2
*
* and we are either e1 or e2. Add a ref from the
* other end.
*/
static int
netmap_pipe_reg(struct netmap_adapter *na, int onoff)
{
struct netmap_pipe_adapter *pna =
(struct netmap_pipe_adapter *)na;
struct netmap_adapter *ona = &pna->peer->up;
int i, error = 0;
enum txrx t;
ND("%p: onoff %d", na, onoff);
if (onoff) {
for_rx_tx(t) {
for (i = 0; i < nma_get_nrings(na, t); i++) {
struct netmap_kring *kring = NMR(na, t)[i];
if (nm_kring_pending_on(kring)) {
/* mark the peer ring as needed */
kring->pipe->nr_kflags |= NKR_NEEDRING;
}
}
}
/* create all missing needed rings on the other end.
* Either our end, or the other, has been marked as
* fake, so the allocation will not be done twice.
*/
error = netmap_mem_rings_create(ona);
if (error)
return error;
/* In case of no error we put our rings in netmap mode */
for_rx_tx(t) {
for (i = 0; i < nma_get_nrings(na, t) + 1; i++) {
struct netmap_kring *kring = NMR(na, t)[i];
if (nm_kring_pending_on(kring)) {
struct netmap_kring *sring, *dring;
/* copy the buffers from the non-fake ring */
if (kring->nr_kflags & NKR_FAKERING) {
sring = kring->pipe;
dring = kring;
} else {
sring = kring;
dring = kring->pipe;
}
memcpy(dring->ring->slot,
sring->ring->slot,
sizeof(struct netmap_slot) *
sring->nkr_num_slots);
/* mark both rings as fake and needed,
* so that buffers will not be
* deleted by the standard machinery
* (we will delete them by ourselves in
* netmap_pipe_krings_delete)
*/
sring->nr_kflags |=
(NKR_FAKERING | NKR_NEEDRING);
dring->nr_kflags |=
(NKR_FAKERING | NKR_NEEDRING);
kring->nr_mode = NKR_NETMAP_ON;
}
}
}
if (na->active_fds == 0)
na->na_flags |= NAF_NETMAP_ON;
} else {
if (na->active_fds == 0)
na->na_flags &= ~NAF_NETMAP_ON;
for_rx_tx(t) {
for (i = 0; i < nma_get_nrings(na, t) + 1; i++) {
struct netmap_kring *kring = NMR(na, t)[i];
if (nm_kring_pending_off(kring)) {
kring->nr_mode = NKR_NETMAP_OFF;
}
}
}
}
if (na->active_fds) {
ND("active_fds %d", na->active_fds);
return 0;
}
if (pna->peer_ref) {
ND("%p: case 1.a or 2.a, nothing to do", na);
return 0;
}
if (onoff) {
ND("%p: case 1.b, drop peer", na);
pna->peer->peer_ref = 0;
netmap_adapter_put(na);
} else {
ND("%p: case 2.b, grab peer", na);
netmap_adapter_get(na);
pna->peer->peer_ref = 1;
}
return error;
}
/* netmap_pipe_krings_delete.
*
* There are two cases:
*
* 1) state is
*
* usr1 --> e1 --> e2
*
* and we are e1 (e2 is not registered, so krings_delete cannot be
* called on it);
*
* 2) state is
*
* usr1 --> e1 e2 <-- usr2
*
* and we are either e1 or e2.
*
* In the former case we have to also delete the krings of e2;
* in the latter case we do nothing.
*/
static void
netmap_pipe_krings_delete(struct netmap_adapter *na)
{
struct netmap_pipe_adapter *pna =
(struct netmap_pipe_adapter *)na;
struct netmap_adapter *sna, *ona; /* na of the other end */
enum txrx t;
int i;
if (!pna->peer_ref) {
ND("%p: case 2, kept alive by peer", na);
return;
}
ona = &pna->peer->up;
/* case 1) above */
ND("%p: case 1, deleting everything", na);
/* To avoid double-frees we zero-out all the buffers in the kernel part
* of each ring. The reason is this: If the user is behaving correctly,
* all buffers are found in exactly one slot in the userspace part of
* some ring. If the user is not behaving correctly, we cannot release
* buffers cleanly anyway. In the latter case, the allocator will
* return to a clean state only when all its users will close.
*/
sna = na;
cleanup:
for_rx_tx(t) {
for (i = 0; i < nma_get_nrings(sna, t) + 1; i++) {
struct netmap_kring *kring = NMR(sna, t)[i];
struct netmap_ring *ring = kring->ring;
uint32_t j, lim = kring->nkr_num_slots - 1;
ND("%s ring %p hwtail %u hwcur %u",
kring->name, ring, kring->nr_hwtail, kring->nr_hwcur);
if (ring == NULL)
continue;
if (kring->nr_hwtail == kring->nr_hwcur)
ring->slot[kring->nr_hwtail].buf_idx = 0;
for (j = nm_next(kring->nr_hwtail, lim);
j != kring->nr_hwcur;
j = nm_next(j, lim))
{
ND("%s[%d] %u", kring->name, j, ring->slot[j].buf_idx);
ring->slot[j].buf_idx = 0;
}
kring->nr_kflags &= ~(NKR_FAKERING | NKR_NEEDRING);
}
}
if (sna != ona && ona->tx_rings) {
sna = ona;
goto cleanup;
}
netmap_mem_rings_delete(na);
netmap_krings_delete(na); /* also zeroes tx_rings etc. */
if (ona->tx_rings == NULL) {
/* already deleted, we must be on an
* cleanup-after-error path */
return;
}
netmap_mem_rings_delete(ona);
netmap_krings_delete(ona);
}
static void
netmap_pipe_dtor(struct netmap_adapter *na)
{
struct netmap_pipe_adapter *pna =
(struct netmap_pipe_adapter *)na;
ND("%p %p", na, pna->parent_ifp);
if (pna->peer_ref) {
ND("%p: clean up peer", na);
pna->peer_ref = 0;
netmap_adapter_put(&pna->peer->up);
}
if (pna->role == NM_PIPE_ROLE_MASTER)
netmap_pipe_remove(pna->parent, pna);
if (pna->parent_ifp)
if_rele(pna->parent_ifp);
netmap_adapter_put(pna->parent);
pna->parent = NULL;
}
int
netmap_get_pipe_na(struct nmreq_header *hdr, struct netmap_adapter **na,
struct netmap_mem_d *nmd, int create)
{
struct nmreq_register *req = (struct nmreq_register *)(uintptr_t)hdr->nr_body;
struct netmap_adapter *pna; /* parent adapter */
struct netmap_pipe_adapter *mna, *sna, *reqna;
struct ifnet *ifp = NULL;
const char *pipe_id = NULL;
int role = 0;
int error, retries = 0;
char *cbra;
/* Try to parse the pipe syntax 'xx{yy' or 'xx}yy'. */
cbra = strrchr(hdr->nr_name, '{');
if (cbra != NULL) {
role = NM_PIPE_ROLE_MASTER;
} else {
cbra = strrchr(hdr->nr_name, '}');
if (cbra != NULL) {
role = NM_PIPE_ROLE_SLAVE;
} else {
ND("not a pipe");
return 0;
}
}
pipe_id = cbra + 1;
if (*pipe_id == '\0' || cbra == hdr->nr_name) {
/* Bracket is the last character, so pipe name is missing;
* or bracket is the first character, so base port name
* is missing. */
return EINVAL;
}
if (req->nr_mode != NR_REG_ALL_NIC && req->nr_mode != NR_REG_ONE_NIC) {
/* We only accept modes involving hardware rings. */
return EINVAL;
}
/* first, try to find the parent adapter */
for (;;) {
char nr_name_orig[NETMAP_REQ_IFNAMSIZ];
int create_error;
/* Temporarily remove the pipe suffix. */
strncpy(nr_name_orig, hdr->nr_name, sizeof(nr_name_orig));
*cbra = '\0';
error = netmap_get_na(hdr, &pna, &ifp, nmd, create);
/* Restore the pipe suffix. */
strncpy(hdr->nr_name, nr_name_orig, sizeof(hdr->nr_name));
if (!error)
break;
if (error != ENXIO || retries++) {
ND("parent lookup failed: %d", error);
return error;
}
ND("try to create a persistent vale port");
/* create a persistent vale port and try again */
*cbra = '\0';
NMG_UNLOCK();
create_error = netmap_vi_create(hdr, 1 /* autodelete */);
NMG_LOCK();
strncpy(hdr->nr_name, nr_name_orig, sizeof(hdr->nr_name));
if (create_error && create_error != EEXIST) {
if (create_error != EOPNOTSUPP) {
D("failed to create a persistent vale port: %d", create_error);
}
return error;
}
}
if (NETMAP_OWNED_BY_KERN(pna)) {
ND("parent busy");
error = EBUSY;
goto put_out;
}
/* next, lookup the pipe id in the parent list */
reqna = NULL;
mna = netmap_pipe_find(pna, pipe_id);
if (mna) {
if (mna->role == role) {
ND("found %s directly at %d", pipe_id, mna->parent_slot);
reqna = mna;
} else {
ND("found %s indirectly at %d", pipe_id, mna->parent_slot);
reqna = mna->peer;
}
/* the pipe we have found already holds a ref to the parent,
* so we need to drop the one we got from netmap_get_na()
*/
netmap_unget_na(pna, ifp);
goto found;
}
ND("pipe %s not found, create %d", pipe_id, create);
if (!create) {
error = ENODEV;
goto put_out;
}
/* we create both master and slave.
* The endpoint we were asked for holds a reference to
* the other one.
*/
mna = nm_os_malloc(sizeof(*mna));
if (mna == NULL) {
error = ENOMEM;
goto put_out;
}
snprintf(mna->up.name, sizeof(mna->up.name), "%s{%s", pna->name, pipe_id);
mna->role = NM_PIPE_ROLE_MASTER;
mna->parent = pna;
mna->parent_ifp = ifp;
mna->up.nm_txsync = netmap_pipe_txsync;
mna->up.nm_rxsync = netmap_pipe_rxsync;
mna->up.nm_register = netmap_pipe_reg;
mna->up.nm_dtor = netmap_pipe_dtor;
mna->up.nm_krings_create = netmap_pipe_krings_create;
mna->up.nm_krings_delete = netmap_pipe_krings_delete;
mna->up.nm_mem = netmap_mem_get(pna->nm_mem);
mna->up.na_flags |= NAF_MEM_OWNER;
mna->up.na_lut = pna->na_lut;
mna->up.num_tx_rings = req->nr_tx_rings;
nm_bound_var(&mna->up.num_tx_rings, 1,
1, NM_PIPE_MAXRINGS, NULL);
mna->up.num_rx_rings = req->nr_rx_rings;
nm_bound_var(&mna->up.num_rx_rings, 1,
1, NM_PIPE_MAXRINGS, NULL);
mna->up.num_tx_desc = req->nr_tx_slots;
nm_bound_var(&mna->up.num_tx_desc, pna->num_tx_desc,
1, NM_PIPE_MAXSLOTS, NULL);
mna->up.num_rx_desc = req->nr_rx_slots;
nm_bound_var(&mna->up.num_rx_desc, pna->num_rx_desc,
1, NM_PIPE_MAXSLOTS, NULL);
error = netmap_attach_common(&mna->up);
if (error)
goto free_mna;
/* register the master with the parent */
error = netmap_pipe_add(pna, mna);
if (error)
goto free_mna;
/* create the slave */
sna = nm_os_malloc(sizeof(*mna));
if (sna == NULL) {
error = ENOMEM;
goto unregister_mna;
}
/* most fields are the same, copy from master and then fix */
*sna = *mna;
sna->up.nm_mem = netmap_mem_get(mna->up.nm_mem);
/* swap the number of tx/rx rings */
sna->up.num_tx_rings = mna->up.num_rx_rings;
sna->up.num_rx_rings = mna->up.num_tx_rings;
snprintf(sna->up.name, sizeof(sna->up.name), "%s}%s", pna->name, pipe_id);
sna->role = NM_PIPE_ROLE_SLAVE;
error = netmap_attach_common(&sna->up);
if (error)
goto free_sna;
/* join the two endpoints */
mna->peer = sna;
sna->peer = mna;
/* we already have a reference to the parent, but we
* need another one for the other endpoint we created
*/
netmap_adapter_get(pna);
/* likewise for the ifp, if any */
if (ifp)
if_ref(ifp);
if (role == NM_PIPE_ROLE_MASTER) {
reqna = mna;
mna->peer_ref = 1;
netmap_adapter_get(&sna->up);
} else {
reqna = sna;
sna->peer_ref = 1;
netmap_adapter_get(&mna->up);
}
ND("created master %p and slave %p", mna, sna);
found:
ND("pipe %s %s at %p", pipe_id,
(reqna->role == NM_PIPE_ROLE_MASTER ? "master" : "slave"), reqna);
*na = &reqna->up;
netmap_adapter_get(*na);
/* keep the reference to the parent.
* It will be released by the req destructor
*/
return 0;
free_sna:
nm_os_free(sna);
unregister_mna:
netmap_pipe_remove(pna, mna);
free_mna:
nm_os_free(mna);
put_out:
netmap_unget_na(pna, ifp);
return error;
}
#endif /* WITH_PIPES */