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

1499 lines
42 KiB
C

/*
* Copyright (C) 2015 Stefano Garzarella
* Copyright (C) 2016 Vincenzo Maffione
* 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.
*
* $FreeBSD$
*/
/*
* common headers
*/
#if defined(__FreeBSD__)
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/types.h>
#include <sys/selinfo.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_var.h>
#include <machine/bus.h>
//#define usleep_range(_1, _2)
#define usleep_range(_1, _2) \
pause_sbt("ptnetmap-sleep", SBT_1US * _1, SBT_1US * 1, C_ABSOLUTE)
#elif defined(linux)
#include <bsd_glue.h>
#endif
#include <net/netmap.h>
#include <dev/netmap/netmap_kern.h>
#include <net/netmap_virt.h>
#include <dev/netmap/netmap_mem2.h>
#ifdef WITH_PTNETMAP_HOST
/* RX cycle without receive any packets */
#define PTN_RX_DRY_CYCLES_MAX 10
/* Limit Batch TX to half ring.
* Currently disabled, since it does not manage NS_MOREFRAG, which
* results in random drops in the VALE txsync. */
//#define PTN_TX_BATCH_LIM(_n) ((_n >> 1))
//#define BUSY_WAIT
#define NETMAP_PT_DEBUG /* Enables communication debugging. */
#ifdef NETMAP_PT_DEBUG
#define DBG(x) x
#else
#define DBG(x)
#endif
#undef RATE
//#define RATE /* Enables communication statistics. */
#ifdef RATE
#define IFRATE(x) x
struct rate_batch_stats {
unsigned long sync;
unsigned long sync_dry;
unsigned long pkt;
};
struct rate_stats {
unsigned long gtxk; /* Guest --> Host Tx kicks. */
unsigned long grxk; /* Guest --> Host Rx kicks. */
unsigned long htxk; /* Host --> Guest Tx kicks. */
unsigned long hrxk; /* Host --> Guest Rx Kicks. */
unsigned long btxwu; /* Backend Tx wake-up. */
unsigned long brxwu; /* Backend Rx wake-up. */
struct rate_batch_stats txbs;
struct rate_batch_stats rxbs;
};
struct rate_context {
struct timer_list timer;
struct rate_stats new;
struct rate_stats old;
};
#define RATE_PERIOD 2
static void
rate_callback(unsigned long arg)
{
struct rate_context * ctx = (struct rate_context *)arg;
struct rate_stats cur = ctx->new;
struct rate_batch_stats *txbs = &cur.txbs;
struct rate_batch_stats *rxbs = &cur.rxbs;
struct rate_batch_stats *txbs_old = &ctx->old.txbs;
struct rate_batch_stats *rxbs_old = &ctx->old.rxbs;
uint64_t tx_batch, rx_batch;
unsigned long txpkts, rxpkts;
unsigned long gtxk, grxk;
int r;
txpkts = txbs->pkt - txbs_old->pkt;
rxpkts = rxbs->pkt - rxbs_old->pkt;
tx_batch = ((txbs->sync - txbs_old->sync) > 0) ?
txpkts / (txbs->sync - txbs_old->sync): 0;
rx_batch = ((rxbs->sync - rxbs_old->sync) > 0) ?
rxpkts / (rxbs->sync - rxbs_old->sync): 0;
/* Fix-up gtxk and grxk estimates. */
gtxk = (cur.gtxk - ctx->old.gtxk) - (cur.btxwu - ctx->old.btxwu);
grxk = (cur.grxk - ctx->old.grxk) - (cur.brxwu - ctx->old.brxwu);
printk("txpkts = %lu Hz\n", txpkts/RATE_PERIOD);
printk("gtxk = %lu Hz\n", gtxk/RATE_PERIOD);
printk("htxk = %lu Hz\n", (cur.htxk - ctx->old.htxk)/RATE_PERIOD);
printk("btxw = %lu Hz\n", (cur.btxwu - ctx->old.btxwu)/RATE_PERIOD);
printk("rxpkts = %lu Hz\n", rxpkts/RATE_PERIOD);
printk("grxk = %lu Hz\n", grxk/RATE_PERIOD);
printk("hrxk = %lu Hz\n", (cur.hrxk - ctx->old.hrxk)/RATE_PERIOD);
printk("brxw = %lu Hz\n", (cur.brxwu - ctx->old.brxwu)/RATE_PERIOD);
printk("txbatch = %llu avg\n", tx_batch);
printk("rxbatch = %llu avg\n", rx_batch);
printk("\n");
ctx->old = cur;
r = mod_timer(&ctx->timer, jiffies +
msecs_to_jiffies(RATE_PERIOD * 1000));
if (unlikely(r))
D("[ptnetmap] Error: mod_timer()\n");
}
static void
rate_batch_stats_update(struct rate_batch_stats *bf, uint32_t pre_tail,
uint32_t act_tail, uint32_t num_slots)
{
int n = (int)act_tail - pre_tail;
if (n) {
if (n < 0)
n += num_slots;
bf->sync++;
bf->pkt += n;
} else {
bf->sync_dry++;
}
}
#else /* !RATE */
#define IFRATE(x)
#endif /* RATE */
struct ptnetmap_state {
/* Kthreads. */
struct nm_kctx **kctxs;
/* Shared memory with the guest (TX/RX) */
struct ptnet_csb_gh __user *csb_gh;
struct ptnet_csb_hg __user *csb_hg;
bool stopped;
/* Netmap adapter wrapping the backend. */
struct netmap_pt_host_adapter *pth_na;
IFRATE(struct rate_context rate_ctx;)
};
static inline void
ptnetmap_kring_dump(const char *title, const struct netmap_kring *kring)
{
D("%s - name: %s hwcur: %d hwtail: %d rhead: %d rcur: %d"
" rtail: %d head: %d cur: %d tail: %d",
title, kring->name, kring->nr_hwcur,
kring->nr_hwtail, kring->rhead, kring->rcur, kring->rtail,
kring->ring->head, kring->ring->cur, kring->ring->tail);
}
/*
* TX functions to set/get and to handle host/guest kick.
*/
/* Enable or disable guest --> host kicks. */
static inline void
pthg_kick_enable(struct ptnet_csb_hg __user *pthg, uint32_t val)
{
CSB_WRITE(pthg, host_need_kick, val);
}
/* Are guest interrupt enabled or disabled? */
static inline uint32_t
ptgh_intr_enabled(struct ptnet_csb_gh __user *ptgh)
{
uint32_t v;
CSB_READ(ptgh, guest_need_kick, v);
return v;
}
/* Handle TX events: from the guest or from the backend */
static void
ptnetmap_tx_handler(void *data, int is_kthread)
{
struct netmap_kring *kring = data;
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)kring->na->na_private;
struct ptnetmap_state *ptns = pth_na->ptns;
struct ptnet_csb_gh __user *ptgh;
struct ptnet_csb_hg __user *pthg;
struct netmap_ring shadow_ring; /* shadow copy of the netmap_ring */
bool more_txspace = false;
struct nm_kctx *kth;
uint32_t num_slots;
int batch;
IFRATE(uint32_t pre_tail);
if (unlikely(!ptns)) {
D("ERROR ptnetmap state is NULL");
return;
}
if (unlikely(ptns->stopped)) {
RD(1, "backend netmap is being stopped");
return;
}
if (unlikely(nm_kr_tryget(kring, 1, NULL))) {
D("ERROR nm_kr_tryget()");
return;
}
/* This is a guess, to be fixed in the rate callback. */
IFRATE(ptns->rate_ctx.new.gtxk++);
/* Get TX ptgh/pthg pointer from the CSB. */
ptgh = ptns->csb_gh + kring->ring_id;
pthg = ptns->csb_hg + kring->ring_id;
kth = ptns->kctxs[kring->ring_id];
num_slots = kring->nkr_num_slots;
/* Disable guest --> host notifications. */
pthg_kick_enable(pthg, 0);
/* Copy the guest kring pointers from the CSB */
ptnetmap_host_read_kring_csb(ptgh, &shadow_ring, num_slots);
for (;;) {
/* If guest moves ahead too fast, let's cut the move so
* that we don't exceed our batch limit. */
batch = shadow_ring.head - kring->nr_hwcur;
if (batch < 0)
batch += num_slots;
#ifdef PTN_TX_BATCH_LIM
if (batch > PTN_TX_BATCH_LIM(num_slots)) {
uint32_t head_lim = kring->nr_hwcur + PTN_TX_BATCH_LIM(num_slots);
if (head_lim >= num_slots)
head_lim -= num_slots;
ND(1, "batch: %d head: %d head_lim: %d", batch, shadow_ring.head,
head_lim);
shadow_ring.head = head_lim;
batch = PTN_TX_BATCH_LIM(num_slots);
}
#endif /* PTN_TX_BATCH_LIM */
if (nm_kr_txspace(kring) <= (num_slots >> 1)) {
shadow_ring.flags |= NAF_FORCE_RECLAIM;
}
/* Netmap prologue */
shadow_ring.tail = kring->rtail;
if (unlikely(nm_txsync_prologue(kring, &shadow_ring) >= num_slots)) {
/* Reinit ring and enable notifications. */
netmap_ring_reinit(kring);
pthg_kick_enable(pthg, 1);
break;
}
if (unlikely(netmap_verbose & NM_VERB_TXSYNC)) {
ptnetmap_kring_dump("pre txsync", kring);
}
IFRATE(pre_tail = kring->rtail);
if (unlikely(kring->nm_sync(kring, shadow_ring.flags))) {
/* Reenable notifications. */
pthg_kick_enable(pthg, 1);
D("ERROR txsync()");
break;
}
/*
* Finalize
* Copy host hwcur and hwtail into the CSB for the guest sync(), and
* do the nm_sync_finalize.
*/
ptnetmap_host_write_kring_csb(pthg, kring->nr_hwcur,
kring->nr_hwtail);
if (kring->rtail != kring->nr_hwtail) {
/* Some more room available in the parent adapter. */
kring->rtail = kring->nr_hwtail;
more_txspace = true;
}
IFRATE(rate_batch_stats_update(&ptns->rate_ctx.new.txbs, pre_tail,
kring->rtail, num_slots));
if (unlikely(netmap_verbose & NM_VERB_TXSYNC)) {
ptnetmap_kring_dump("post txsync", kring);
}
#ifndef BUSY_WAIT
/* Interrupt the guest if needed. */
if (more_txspace && ptgh_intr_enabled(ptgh) && is_kthread) {
/* Disable guest kick to avoid sending unnecessary kicks */
nm_os_kctx_send_irq(kth);
IFRATE(ptns->rate_ctx.new.htxk++);
more_txspace = false;
}
#endif
/* Read CSB to see if there is more work to do. */
ptnetmap_host_read_kring_csb(ptgh, &shadow_ring, num_slots);
#ifndef BUSY_WAIT
if (shadow_ring.head == kring->rhead) {
/*
* No more packets to transmit. We enable notifications and
* go to sleep, waiting for a kick from the guest when new
* new slots are ready for transmission.
*/
if (is_kthread) {
usleep_range(1,1);
}
/* Reenable notifications. */
pthg_kick_enable(pthg, 1);
/* Doublecheck. */
ptnetmap_host_read_kring_csb(ptgh, &shadow_ring, num_slots);
if (shadow_ring.head != kring->rhead) {
/* We won the race condition, there are more packets to
* transmit. Disable notifications and do another cycle */
pthg_kick_enable(pthg, 0);
continue;
}
break;
}
if (nm_kr_txempty(kring)) {
/* No more available TX slots. We stop waiting for a notification
* from the backend (netmap_tx_irq). */
ND(1, "TX ring");
break;
}
#endif
if (unlikely(ptns->stopped)) {
D("backend netmap is being stopped");
break;
}
}
nm_kr_put(kring);
if (more_txspace && ptgh_intr_enabled(ptgh) && is_kthread) {
nm_os_kctx_send_irq(kth);
IFRATE(ptns->rate_ctx.new.htxk++);
}
}
/* Called on backend nm_notify when there is no worker thread. */
static void
ptnetmap_tx_nothread_notify(void *data)
{
struct netmap_kring *kring = data;
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)kring->na->na_private;
struct ptnetmap_state *ptns = pth_na->ptns;
if (unlikely(!ptns)) {
D("ERROR ptnetmap state is NULL");
return;
}
if (unlikely(ptns->stopped)) {
D("backend netmap is being stopped");
return;
}
/* We cannot access the CSB here (to check ptgh->guest_need_kick),
* unless we switch address space to the one of the guest. For now
* we unconditionally inject an interrupt. */
nm_os_kctx_send_irq(ptns->kctxs[kring->ring_id]);
IFRATE(ptns->rate_ctx.new.htxk++);
ND(1, "%s interrupt", kring->name);
}
/*
* We need RX kicks from the guest when (tail == head-1), where we wait
* for the guest to refill.
*/
#ifndef BUSY_WAIT
static inline int
ptnetmap_norxslots(struct netmap_kring *kring, uint32_t g_head)
{
return (NM_ACCESS_ONCE(kring->nr_hwtail) == nm_prev(g_head,
kring->nkr_num_slots - 1));
}
#endif /* !BUSY_WAIT */
/* Handle RX events: from the guest or from the backend */
static void
ptnetmap_rx_handler(void *data, int is_kthread)
{
struct netmap_kring *kring = data;
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)kring->na->na_private;
struct ptnetmap_state *ptns = pth_na->ptns;
struct ptnet_csb_gh __user *ptgh;
struct ptnet_csb_hg __user *pthg;
struct netmap_ring shadow_ring; /* shadow copy of the netmap_ring */
struct nm_kctx *kth;
uint32_t num_slots;
int dry_cycles = 0;
bool some_recvd = false;
IFRATE(uint32_t pre_tail);
if (unlikely(!ptns || !ptns->pth_na)) {
D("ERROR ptnetmap state %p, ptnetmap host adapter %p", ptns,
ptns ? ptns->pth_na : NULL);
return;
}
if (unlikely(ptns->stopped)) {
RD(1, "backend netmap is being stopped");
return;
}
if (unlikely(nm_kr_tryget(kring, 1, NULL))) {
D("ERROR nm_kr_tryget()");
return;
}
/* This is a guess, to be fixed in the rate callback. */
IFRATE(ptns->rate_ctx.new.grxk++);
/* Get RX ptgh and pthg pointers from the CSB. */
ptgh = ptns->csb_gh + (pth_na->up.num_tx_rings + kring->ring_id);
pthg = ptns->csb_hg + (pth_na->up.num_tx_rings + kring->ring_id);
kth = ptns->kctxs[pth_na->up.num_tx_rings + kring->ring_id];
num_slots = kring->nkr_num_slots;
/* Disable notifications. */
pthg_kick_enable(pthg, 0);
/* Copy the guest kring pointers from the CSB */
ptnetmap_host_read_kring_csb(ptgh, &shadow_ring, num_slots);
for (;;) {
uint32_t hwtail;
/* Netmap prologue */
shadow_ring.tail = kring->rtail;
if (unlikely(nm_rxsync_prologue(kring, &shadow_ring) >= num_slots)) {
/* Reinit ring and enable notifications. */
netmap_ring_reinit(kring);
pthg_kick_enable(pthg, 1);
break;
}
if (unlikely(netmap_verbose & NM_VERB_RXSYNC)) {
ptnetmap_kring_dump("pre rxsync", kring);
}
IFRATE(pre_tail = kring->rtail);
if (unlikely(kring->nm_sync(kring, shadow_ring.flags))) {
/* Reenable notifications. */
pthg_kick_enable(pthg, 1);
D("ERROR rxsync()");
break;
}
/*
* Finalize
* Copy host hwcur and hwtail into the CSB for the guest sync()
*/
hwtail = NM_ACCESS_ONCE(kring->nr_hwtail);
ptnetmap_host_write_kring_csb(pthg, kring->nr_hwcur, hwtail);
if (kring->rtail != hwtail) {
kring->rtail = hwtail;
some_recvd = true;
dry_cycles = 0;
} else {
dry_cycles++;
}
IFRATE(rate_batch_stats_update(&ptns->rate_ctx.new.rxbs, pre_tail,
kring->rtail, num_slots));
if (unlikely(netmap_verbose & NM_VERB_RXSYNC)) {
ptnetmap_kring_dump("post rxsync", kring);
}
#ifndef BUSY_WAIT
/* Interrupt the guest if needed. */
if (some_recvd && ptgh_intr_enabled(ptgh)) {
/* Disable guest kick to avoid sending unnecessary kicks */
nm_os_kctx_send_irq(kth);
IFRATE(ptns->rate_ctx.new.hrxk++);
some_recvd = false;
}
#endif
/* Read CSB to see if there is more work to do. */
ptnetmap_host_read_kring_csb(ptgh, &shadow_ring, num_slots);
#ifndef BUSY_WAIT
if (ptnetmap_norxslots(kring, shadow_ring.head)) {
/*
* No more slots available for reception. We enable notification and
* go to sleep, waiting for a kick from the guest when new receive
* slots are available.
*/
usleep_range(1,1);
/* Reenable notifications. */
pthg_kick_enable(pthg, 1);
/* Doublecheck. */
ptnetmap_host_read_kring_csb(ptgh, &shadow_ring, num_slots);
if (!ptnetmap_norxslots(kring, shadow_ring.head)) {
/* We won the race condition, more slots are available. Disable
* notifications and do another cycle. */
pthg_kick_enable(pthg, 0);
continue;
}
break;
}
hwtail = NM_ACCESS_ONCE(kring->nr_hwtail);
if (unlikely(hwtail == kring->rhead ||
dry_cycles >= PTN_RX_DRY_CYCLES_MAX)) {
/* No more packets to be read from the backend. We stop and
* wait for a notification from the backend (netmap_rx_irq). */
ND(1, "nr_hwtail: %d rhead: %d dry_cycles: %d",
hwtail, kring->rhead, dry_cycles);
break;
}
#endif
if (unlikely(ptns->stopped)) {
D("backend netmap is being stopped");
break;
}
}
nm_kr_put(kring);
/* Interrupt the guest if needed. */
if (some_recvd && ptgh_intr_enabled(ptgh)) {
nm_os_kctx_send_irq(kth);
IFRATE(ptns->rate_ctx.new.hrxk++);
}
}
#ifdef NETMAP_PT_DEBUG
static void
ptnetmap_print_configuration(struct ptnetmap_cfg *cfg)
{
int k;
D("ptnetmap configuration:");
D(" CSB @%p@:%p, num_rings=%u, cfgtype %08x", cfg->csb_gh,
cfg->csb_hg, cfg->num_rings, cfg->cfgtype);
for (k = 0; k < cfg->num_rings; k++) {
switch (cfg->cfgtype) {
case PTNETMAP_CFGTYPE_QEMU: {
struct ptnetmap_cfgentry_qemu *e =
(struct ptnetmap_cfgentry_qemu *)(cfg+1) + k;
D(" ring #%d: ioeventfd=%lu, irqfd=%lu", k,
(unsigned long)e->ioeventfd,
(unsigned long)e->irqfd);
break;
}
case PTNETMAP_CFGTYPE_BHYVE:
{
struct ptnetmap_cfgentry_bhyve *e =
(struct ptnetmap_cfgentry_bhyve *)(cfg+1) + k;
D(" ring #%d: wchan=%lu, ioctl_fd=%lu, "
"ioctl_cmd=%lu, msix_msg_data=%lu, msix_addr=%lu",
k, (unsigned long)e->wchan,
(unsigned long)e->ioctl_fd,
(unsigned long)e->ioctl_cmd,
(unsigned long)e->ioctl_data.msg_data,
(unsigned long)e->ioctl_data.addr);
break;
}
}
}
}
#endif /* NETMAP_PT_DEBUG */
/* Copy actual state of the host ring into the CSB for the guest init */
static int
ptnetmap_kring_snapshot(struct netmap_kring *kring,
struct ptnet_csb_gh __user *ptgh,
struct ptnet_csb_hg __user *pthg)
{
if (CSB_WRITE(ptgh, head, kring->rhead))
goto err;
if (CSB_WRITE(ptgh, cur, kring->rcur))
goto err;
if (CSB_WRITE(pthg, hwcur, kring->nr_hwcur))
goto err;
if (CSB_WRITE(pthg, hwtail, NM_ACCESS_ONCE(kring->nr_hwtail)))
goto err;
DBG(ptnetmap_kring_dump("ptnetmap_kring_snapshot", kring);)
return 0;
err:
return EFAULT;
}
static struct netmap_kring *
ptnetmap_kring(struct netmap_pt_host_adapter *pth_na, int k)
{
if (k < pth_na->up.num_tx_rings) {
return pth_na->up.tx_rings[k];
}
return pth_na->up.rx_rings[k - pth_na->up.num_tx_rings];
}
static int
ptnetmap_krings_snapshot(struct netmap_pt_host_adapter *pth_na)
{
struct ptnetmap_state *ptns = pth_na->ptns;
struct netmap_kring *kring;
unsigned int num_rings;
int err = 0, k;
num_rings = pth_na->up.num_tx_rings +
pth_na->up.num_rx_rings;
for (k = 0; k < num_rings; k++) {
kring = ptnetmap_kring(pth_na, k);
err |= ptnetmap_kring_snapshot(kring, ptns->csb_gh + k,
ptns->csb_hg + k);
}
return err;
}
/*
* Functions to create kernel contexts, and start/stop the workers.
*/
static int
ptnetmap_create_kctxs(struct netmap_pt_host_adapter *pth_na,
struct ptnetmap_cfg *cfg, int use_tx_kthreads)
{
struct ptnetmap_state *ptns = pth_na->ptns;
struct nm_kctx_cfg nmk_cfg;
unsigned int num_rings;
uint8_t *cfg_entries = (uint8_t *)(cfg + 1);
unsigned int expected_cfgtype = 0;
int k;
#if defined(__FreeBSD__)
expected_cfgtype = PTNETMAP_CFGTYPE_BHYVE;
#elif defined(linux)
expected_cfgtype = PTNETMAP_CFGTYPE_QEMU;
#endif
if (cfg->cfgtype != expected_cfgtype) {
D("Unsupported cfgtype %u", cfg->cfgtype);
return EINVAL;
}
num_rings = pth_na->up.num_tx_rings +
pth_na->up.num_rx_rings;
for (k = 0; k < num_rings; k++) {
nmk_cfg.attach_user = 1; /* attach kthread to user process */
nmk_cfg.worker_private = ptnetmap_kring(pth_na, k);
nmk_cfg.type = k;
if (k < pth_na->up.num_tx_rings) {
nmk_cfg.worker_fn = ptnetmap_tx_handler;
nmk_cfg.use_kthread = use_tx_kthreads;
nmk_cfg.notify_fn = ptnetmap_tx_nothread_notify;
} else {
nmk_cfg.worker_fn = ptnetmap_rx_handler;
nmk_cfg.use_kthread = 1;
}
ptns->kctxs[k] = nm_os_kctx_create(&nmk_cfg,
cfg_entries + k * cfg->entry_size);
if (ptns->kctxs[k] == NULL) {
goto err;
}
}
return 0;
err:
for (k = 0; k < num_rings; k++) {
if (ptns->kctxs[k]) {
nm_os_kctx_destroy(ptns->kctxs[k]);
ptns->kctxs[k] = NULL;
}
}
return EFAULT;
}
static int
ptnetmap_start_kctx_workers(struct netmap_pt_host_adapter *pth_na)
{
struct ptnetmap_state *ptns = pth_na->ptns;
int num_rings;
int error;
int k;
if (!ptns) {
D("BUG ptns is NULL");
return EFAULT;
}
ptns->stopped = false;
num_rings = ptns->pth_na->up.num_tx_rings +
ptns->pth_na->up.num_rx_rings;
for (k = 0; k < num_rings; k++) {
//nm_os_kctx_worker_setaff(ptns->kctxs[k], xxx);
error = nm_os_kctx_worker_start(ptns->kctxs[k]);
if (error) {
return error;
}
}
return 0;
}
static void
ptnetmap_stop_kctx_workers(struct netmap_pt_host_adapter *pth_na)
{
struct ptnetmap_state *ptns = pth_na->ptns;
int num_rings;
int k;
if (!ptns) {
/* Nothing to do. */
return;
}
ptns->stopped = true;
num_rings = ptns->pth_na->up.num_tx_rings +
ptns->pth_na->up.num_rx_rings;
for (k = 0; k < num_rings; k++) {
nm_os_kctx_worker_stop(ptns->kctxs[k]);
}
}
static int nm_unused_notify(struct netmap_kring *, int);
static int nm_pt_host_notify(struct netmap_kring *, int);
/* Create ptnetmap state and switch parent adapter to ptnetmap mode. */
static int
ptnetmap_create(struct netmap_pt_host_adapter *pth_na,
struct ptnetmap_cfg *cfg)
{
int use_tx_kthreads = ptnetmap_tx_workers; /* snapshot */
struct ptnetmap_state *ptns;
unsigned int num_rings;
int ret, i;
/* Check if ptnetmap state is already there. */
if (pth_na->ptns) {
D("ERROR adapter %p already in ptnetmap mode", pth_na->parent);
return EINVAL;
}
num_rings = pth_na->up.num_tx_rings + pth_na->up.num_rx_rings;
if (num_rings != cfg->num_rings) {
D("ERROR configuration mismatch, expected %u rings, found %u",
num_rings, cfg->num_rings);
return EINVAL;
}
if (!use_tx_kthreads && na_is_generic(pth_na->parent)) {
D("ERROR ptnetmap direct transmission not supported with "
"passed-through emulated adapters");
return EOPNOTSUPP;
}
ptns = nm_os_malloc(sizeof(*ptns) + num_rings * sizeof(*ptns->kctxs));
if (!ptns) {
return ENOMEM;
}
ptns->kctxs = (struct nm_kctx **)(ptns + 1);
ptns->stopped = true;
/* Cross-link data structures. */
pth_na->ptns = ptns;
ptns->pth_na = pth_na;
/* Store the CSB address provided by the hypervisor. */
ptns->csb_gh = cfg->csb_gh;
ptns->csb_hg = cfg->csb_hg;
DBG(ptnetmap_print_configuration(cfg));
/* Create kernel contexts. */
if ((ret = ptnetmap_create_kctxs(pth_na, cfg, use_tx_kthreads))) {
D("ERROR ptnetmap_create_kctxs()");
goto err;
}
/* Copy krings state into the CSB for the guest initialization */
if ((ret = ptnetmap_krings_snapshot(pth_na))) {
D("ERROR ptnetmap_krings_snapshot()");
goto err;
}
/* Overwrite parent nm_notify krings callback, and
* clear NAF_BDG_MAYSLEEP if needed. */
pth_na->parent->na_private = pth_na;
pth_na->parent_nm_notify = pth_na->parent->nm_notify;
pth_na->parent->nm_notify = nm_unused_notify;
pth_na->parent_na_flags = pth_na->parent->na_flags;
if (!use_tx_kthreads) {
/* VALE port txsync is executed under spinlock on Linux, so
* we need to make sure the bridge cannot sleep. */
pth_na->parent->na_flags &= ~NAF_BDG_MAYSLEEP;
}
for (i = 0; i < pth_na->parent->num_rx_rings; i++) {
pth_na->up.rx_rings[i]->save_notify =
pth_na->up.rx_rings[i]->nm_notify;
pth_na->up.rx_rings[i]->nm_notify = nm_pt_host_notify;
}
for (i = 0; i < pth_na->parent->num_tx_rings; i++) {
pth_na->up.tx_rings[i]->save_notify =
pth_na->up.tx_rings[i]->nm_notify;
pth_na->up.tx_rings[i]->nm_notify = nm_pt_host_notify;
}
#ifdef RATE
memset(&ptns->rate_ctx, 0, sizeof(ptns->rate_ctx));
setup_timer(&ptns->rate_ctx.timer, &rate_callback,
(unsigned long)&ptns->rate_ctx);
if (mod_timer(&ptns->rate_ctx.timer, jiffies + msecs_to_jiffies(1500)))
D("[ptn] Error: mod_timer()\n");
#endif
DBG(D("[%s] ptnetmap configuration DONE", pth_na->up.name));
return 0;
err:
pth_na->ptns = NULL;
nm_os_free(ptns);
return ret;
}
/* Switch parent adapter back to normal mode and destroy
* ptnetmap state. */
static void
ptnetmap_delete(struct netmap_pt_host_adapter *pth_na)
{
struct ptnetmap_state *ptns = pth_na->ptns;
int num_rings;
int i;
if (!ptns) {
/* Nothing to do. */
return;
}
/* Restore parent adapter callbacks. */
pth_na->parent->nm_notify = pth_na->parent_nm_notify;
pth_na->parent->na_private = NULL;
pth_na->parent->na_flags = pth_na->parent_na_flags;
for (i = 0; i < pth_na->parent->num_rx_rings; i++) {
pth_na->up.rx_rings[i]->nm_notify =
pth_na->up.rx_rings[i]->save_notify;
pth_na->up.rx_rings[i]->save_notify = NULL;
}
for (i = 0; i < pth_na->parent->num_tx_rings; i++) {
pth_na->up.tx_rings[i]->nm_notify =
pth_na->up.tx_rings[i]->save_notify;
pth_na->up.tx_rings[i]->save_notify = NULL;
}
/* Destroy kernel contexts. */
num_rings = ptns->pth_na->up.num_tx_rings +
ptns->pth_na->up.num_rx_rings;
for (i = 0; i < num_rings; i++) {
nm_os_kctx_destroy(ptns->kctxs[i]);
ptns->kctxs[i] = NULL;
}
IFRATE(del_timer(&ptns->rate_ctx.timer));
nm_os_free(ptns);
pth_na->ptns = NULL;
DBG(D("[%s] ptnetmap deleted", pth_na->up.name));
}
/*
* Called by netmap_ioctl().
* Operation is indicated in nr_name.
*
* Called without NMG_LOCK.
*/
int
ptnetmap_ctl(const char *nr_name, int create, struct netmap_adapter *na)
{
struct netmap_pt_host_adapter *pth_na;
struct ptnetmap_cfg *cfg = NULL;
int error = 0;
DBG(D("name: %s", nr_name));
if (!nm_ptnetmap_host_on(na)) {
D("ERROR Netmap adapter %p is not a ptnetmap host adapter",
na);
return ENXIO;
}
pth_na = (struct netmap_pt_host_adapter *)na;
NMG_LOCK();
if (create) {
/* Read hypervisor configuration from userspace. */
/* TODO */
if (!cfg) {
goto out;
}
/* Create ptnetmap state (kctxs, ...) and switch parent
* adapter to ptnetmap mode. */
error = ptnetmap_create(pth_na, cfg);
nm_os_free(cfg);
if (error) {
goto out;
}
/* Start kthreads. */
error = ptnetmap_start_kctx_workers(pth_na);
if (error)
ptnetmap_delete(pth_na);
} else {
/* Stop kthreads. */
ptnetmap_stop_kctx_workers(pth_na);
/* Switch parent adapter back to normal mode and destroy
* ptnetmap state (kthreads, ...). */
ptnetmap_delete(pth_na);
}
out:
NMG_UNLOCK();
return error;
}
/* nm_notify callbacks for ptnetmap */
static int
nm_pt_host_notify(struct netmap_kring *kring, int flags)
{
struct netmap_adapter *na = kring->na;
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)na->na_private;
struct ptnetmap_state *ptns;
int k;
/* First check that the passthrough port is not being destroyed. */
if (unlikely(!pth_na)) {
return NM_IRQ_COMPLETED;
}
ptns = pth_na->ptns;
if (unlikely(!ptns || ptns->stopped)) {
return NM_IRQ_COMPLETED;
}
k = kring->ring_id;
/* Notify kthreads (wake up if needed) */
if (kring->tx == NR_TX) {
ND(1, "TX backend irq");
IFRATE(ptns->rate_ctx.new.btxwu++);
} else {
k += pth_na->up.num_tx_rings;
ND(1, "RX backend irq");
IFRATE(ptns->rate_ctx.new.brxwu++);
}
nm_os_kctx_worker_wakeup(ptns->kctxs[k]);
return NM_IRQ_COMPLETED;
}
static int
nm_unused_notify(struct netmap_kring *kring, int flags)
{
D("BUG this should never be called");
return ENXIO;
}
/* nm_config callback for bwrap */
static int
nm_pt_host_config(struct netmap_adapter *na, struct nm_config_info *info)
{
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)na;
struct netmap_adapter *parent = pth_na->parent;
int error;
//XXX: maybe calling parent->nm_config is better
/* forward the request */
error = netmap_update_config(parent);
info->num_rx_rings = na->num_rx_rings = parent->num_rx_rings;
info->num_tx_rings = na->num_tx_rings = parent->num_tx_rings;
info->num_tx_descs = na->num_tx_desc = parent->num_tx_desc;
info->num_rx_descs = na->num_rx_desc = parent->num_rx_desc;
info->rx_buf_maxsize = na->rx_buf_maxsize = parent->rx_buf_maxsize;
return error;
}
/* nm_krings_create callback for ptnetmap */
static int
nm_pt_host_krings_create(struct netmap_adapter *na)
{
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)na;
struct netmap_adapter *parent = pth_na->parent;
enum txrx t;
int error;
DBG(D("%s", pth_na->up.name));
/* create the parent krings */
error = parent->nm_krings_create(parent);
if (error) {
return error;
}
/* A ptnetmap host adapter points the very same krings
* as its parent adapter. These pointer are used in the
* TX/RX worker functions. */
na->tx_rings = parent->tx_rings;
na->rx_rings = parent->rx_rings;
na->tailroom = parent->tailroom;
for_rx_tx(t) {
struct netmap_kring *kring;
/* Parent's kring_create function will initialize
* its own na->si. We have to init our na->si here. */
nm_os_selinfo_init(&na->si[t]);
/* Force the mem_rings_create() method to create the
* host rings independently on what the regif asked for:
* these rings are needed by the guest ptnetmap adapter
* anyway. */
kring = NMR(na, t)[nma_get_nrings(na, t)];
kring->nr_kflags |= NKR_NEEDRING;
}
return 0;
}
/* nm_krings_delete callback for ptnetmap */
static void
nm_pt_host_krings_delete(struct netmap_adapter *na)
{
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)na;
struct netmap_adapter *parent = pth_na->parent;
DBG(D("%s", pth_na->up.name));
parent->nm_krings_delete(parent);
na->tx_rings = na->rx_rings = na->tailroom = NULL;
}
/* nm_register callback */
static int
nm_pt_host_register(struct netmap_adapter *na, int onoff)
{
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)na;
struct netmap_adapter *parent = pth_na->parent;
int error;
DBG(D("%s onoff %d", pth_na->up.name, onoff));
if (onoff) {
/* netmap_do_regif has been called on the ptnetmap na.
* We need to pass the information about the
* memory allocator to the parent before
* putting it in netmap mode
*/
parent->na_lut = na->na_lut;
}
/* forward the request to the parent */
error = parent->nm_register(parent, onoff);
if (error)
return error;
if (onoff) {
na->na_flags |= NAF_NETMAP_ON | NAF_PTNETMAP_HOST;
} else {
ptnetmap_delete(pth_na);
na->na_flags &= ~(NAF_NETMAP_ON | NAF_PTNETMAP_HOST);
}
return 0;
}
/* nm_dtor callback */
static void
nm_pt_host_dtor(struct netmap_adapter *na)
{
struct netmap_pt_host_adapter *pth_na =
(struct netmap_pt_host_adapter *)na;
struct netmap_adapter *parent = pth_na->parent;
DBG(D("%s", pth_na->up.name));
/* The equivalent of NETMAP_PT_HOST_DELETE if the hypervisor
* didn't do it. */
ptnetmap_stop_kctx_workers(pth_na);
ptnetmap_delete(pth_na);
parent->na_flags &= ~NAF_BUSY;
netmap_adapter_put(pth_na->parent);
pth_na->parent = NULL;
}
/* check if nmr is a request for a ptnetmap adapter that we can satisfy */
int
netmap_get_pt_host_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 nmreq_register preq;
struct netmap_adapter *parent; /* target adapter */
struct netmap_pt_host_adapter *pth_na;
struct ifnet *ifp = NULL;
int error;
/* Check if it is a request for a ptnetmap adapter */
if ((req->nr_flags & (NR_PTNETMAP_HOST)) == 0) {
return 0;
}
D("Requesting a ptnetmap host adapter");
pth_na = nm_os_malloc(sizeof(*pth_na));
if (pth_na == NULL) {
D("ERROR malloc");
return ENOMEM;
}
/* first, try to find the adapter that we want to passthrough
* We use the same req, after we have turned off the ptnetmap flag.
* In this way we can potentially passthrough everything netmap understands.
*/
memcpy(&preq, req, sizeof(preq));
preq.nr_flags &= ~(NR_PTNETMAP_HOST);
hdr->nr_body = (uintptr_t)&preq;
error = netmap_get_na(hdr, &parent, &ifp, nmd, create);
hdr->nr_body = (uintptr_t)req;
if (error) {
D("parent lookup failed: %d", error);
goto put_out_noputparent;
}
DBG(D("found parent: %s", parent->name));
/* make sure the interface is not already in use */
if (NETMAP_OWNED_BY_ANY(parent)) {
D("NIC %s busy, cannot ptnetmap", parent->name);
error = EBUSY;
goto put_out;
}
pth_na->parent = parent;
/* Follow netmap_attach()-like operations for the host
* ptnetmap adapter. */
//XXX pth_na->up.na_flags = parent->na_flags;
pth_na->up.num_rx_rings = parent->num_rx_rings;
pth_na->up.num_tx_rings = parent->num_tx_rings;
pth_na->up.num_tx_desc = parent->num_tx_desc;
pth_na->up.num_rx_desc = parent->num_rx_desc;
pth_na->up.nm_dtor = nm_pt_host_dtor;
pth_na->up.nm_register = nm_pt_host_register;
/* Reuse parent's adapter txsync and rxsync methods. */
pth_na->up.nm_txsync = parent->nm_txsync;
pth_na->up.nm_rxsync = parent->nm_rxsync;
pth_na->up.nm_krings_create = nm_pt_host_krings_create;
pth_na->up.nm_krings_delete = nm_pt_host_krings_delete;
pth_na->up.nm_config = nm_pt_host_config;
/* Set the notify method only or convenience, it will never
* be used, since - differently from default krings_create - we
* ptnetmap krings_create callback inits kring->nm_notify
* directly. */
pth_na->up.nm_notify = nm_unused_notify;
pth_na->up.nm_mem = netmap_mem_get(parent->nm_mem);
pth_na->up.na_flags |= NAF_HOST_RINGS;
error = netmap_attach_common(&pth_na->up);
if (error) {
D("ERROR netmap_attach_common()");
goto put_out;
}
*na = &pth_na->up;
/* set parent busy, because attached for ptnetmap */
parent->na_flags |= NAF_BUSY;
strncpy(pth_na->up.name, parent->name, sizeof(pth_na->up.name));
strcat(pth_na->up.name, "-PTN");
netmap_adapter_get(*na);
DBG(D("%s ptnetmap request DONE", pth_na->up.name));
/* drop the reference to the ifp, if any */
if (ifp)
if_rele(ifp);
return 0;
put_out:
netmap_adapter_put(parent);
if (ifp)
if_rele(ifp);
put_out_noputparent:
nm_os_free(pth_na);
return error;
}
#endif /* WITH_PTNETMAP_HOST */
#ifdef WITH_PTNETMAP_GUEST
/*
* Guest ptnetmap txsync()/rxsync() routines, used in ptnet device drivers.
* These routines are reused across the different operating systems supported
* by netmap.
*/
/*
* Reconcile host and guest views of the transmit ring.
*
* Guest user wants to transmit packets up to the one before ring->head,
* and guest kernel knows tx_ring->hwcur is the first packet unsent
* by the host kernel.
*
* We push out as many packets as possible, and possibly
* reclaim buffers from previously completed transmission.
*
* Notifications from the host are enabled only if the user guest would
* block (no space in the ring).
*/
bool
netmap_pt_guest_txsync(struct ptnet_csb_gh *ptgh, struct ptnet_csb_hg *pthg,
struct netmap_kring *kring, int flags)
{
bool notify = false;
/* Disable notifications */
ptgh->guest_need_kick = 0;
/*
* First part: tell the host (updating the CSB) to process the new
* packets.
*/
kring->nr_hwcur = pthg->hwcur;
ptnetmap_guest_write_kring_csb(ptgh, kring->rcur, kring->rhead);
/* Ask for a kick from a guest to the host if needed. */
if (((kring->rhead != kring->nr_hwcur || nm_kr_txempty(kring))
&& NM_ACCESS_ONCE(pthg->host_need_kick)) ||
(flags & NAF_FORCE_RECLAIM)) {
ptgh->sync_flags = flags;
notify = true;
}
/*
* Second part: reclaim buffers for completed transmissions.
*/
if (nm_kr_txempty(kring) || (flags & NAF_FORCE_RECLAIM)) {
ptnetmap_guest_read_kring_csb(pthg, kring);
}
/*
* No more room in the ring for new transmissions. The user thread will
* go to sleep and we need to be notified by the host when more free
* space is available.
*/
if (nm_kr_txempty(kring) && !(kring->nr_kflags & NKR_NOINTR)) {
/* Reenable notifications. */
ptgh->guest_need_kick = 1;
/* Double check */
ptnetmap_guest_read_kring_csb(pthg, kring);
/* If there is new free space, disable notifications */
if (unlikely(!nm_kr_txempty(kring))) {
ptgh->guest_need_kick = 0;
}
}
ND(1, "%s CSB(head:%u cur:%u hwtail:%u) KRING(head:%u cur:%u tail:%u)",
kring->name, ptgh->head, ptgh->cur, pthg->hwtail,
kring->rhead, kring->rcur, kring->nr_hwtail);
return notify;
}
/*
* Reconcile host and guest view of the receive ring.
*
* Update hwcur/hwtail from host (reading from CSB).
*
* If guest user has released buffers up to the one before ring->head, we
* also give them to the host.
*
* Notifications from the host are enabled only if the user guest would
* block (no more completed slots in the ring).
*/
bool
netmap_pt_guest_rxsync(struct ptnet_csb_gh *ptgh, struct ptnet_csb_hg *pthg,
struct netmap_kring *kring, int flags)
{
bool notify = false;
/* Disable notifications */
ptgh->guest_need_kick = 0;
/*
* First part: import newly received packets, by updating the kring
* hwtail to the hwtail known from the host (read from the CSB).
* This also updates the kring hwcur.
*/
ptnetmap_guest_read_kring_csb(pthg, kring);
kring->nr_kflags &= ~NKR_PENDINTR;
/*
* Second part: tell the host about the slots that guest user has
* released, by updating cur and head in the CSB.
*/
if (kring->rhead != kring->nr_hwcur) {
ptnetmap_guest_write_kring_csb(ptgh, kring->rcur,
kring->rhead);
/* Ask for a kick from the guest to the host if needed. */
if (NM_ACCESS_ONCE(pthg->host_need_kick)) {
ptgh->sync_flags = flags;
notify = true;
}
}
/*
* No more completed RX slots. The user thread will go to sleep and
* we need to be notified by the host when more RX slots have been
* completed.
*/
if (nm_kr_rxempty(kring) && !(kring->nr_kflags & NKR_NOINTR)) {
/* Reenable notifications. */
ptgh->guest_need_kick = 1;
/* Double check */
ptnetmap_guest_read_kring_csb(pthg, kring);
/* If there are new slots, disable notifications. */
if (!nm_kr_rxempty(kring)) {
ptgh->guest_need_kick = 0;
}
}
ND(1, "%s CSB(head:%u cur:%u hwtail:%u) KRING(head:%u cur:%u tail:%u)",
kring->name, ptgh->head, ptgh->cur, pthg->hwtail,
kring->rhead, kring->rcur, kring->nr_hwtail);
return notify;
}
/*
* Callbacks for ptnet drivers: nm_krings_create, nm_krings_delete, nm_dtor.
*/
int
ptnet_nm_krings_create(struct netmap_adapter *na)
{
struct netmap_pt_guest_adapter *ptna =
(struct netmap_pt_guest_adapter *)na; /* Upcast. */
struct netmap_adapter *na_nm = &ptna->hwup.up;
struct netmap_adapter *na_dr = &ptna->dr.up;
int ret;
if (ptna->backend_regifs) {
return 0;
}
/* Create krings on the public netmap adapter. */
ret = netmap_hw_krings_create(na_nm);
if (ret) {
return ret;
}
/* Copy krings into the netmap adapter private to the driver. */
na_dr->tx_rings = na_nm->tx_rings;
na_dr->rx_rings = na_nm->rx_rings;
return 0;
}
void
ptnet_nm_krings_delete(struct netmap_adapter *na)
{
struct netmap_pt_guest_adapter *ptna =
(struct netmap_pt_guest_adapter *)na; /* Upcast. */
struct netmap_adapter *na_nm = &ptna->hwup.up;
struct netmap_adapter *na_dr = &ptna->dr.up;
if (ptna->backend_regifs) {
return;
}
na_dr->tx_rings = NULL;
na_dr->rx_rings = NULL;
netmap_hw_krings_delete(na_nm);
}
void
ptnet_nm_dtor(struct netmap_adapter *na)
{
struct netmap_pt_guest_adapter *ptna =
(struct netmap_pt_guest_adapter *)na;
netmap_mem_put(ptna->dr.up.nm_mem);
memset(&ptna->dr, 0, sizeof(ptna->dr));
netmap_mem_pt_guest_ifp_del(na->nm_mem, na->ifp);
}
int
netmap_pt_guest_attach(struct netmap_adapter *arg,
unsigned int nifp_offset, unsigned int memid)
{
struct netmap_pt_guest_adapter *ptna;
struct ifnet *ifp = arg ? arg->ifp : NULL;
int error;
/* get allocator */
arg->nm_mem = netmap_mem_pt_guest_new(ifp, nifp_offset, memid);
if (arg->nm_mem == NULL)
return ENOMEM;
arg->na_flags |= NAF_MEM_OWNER;
error = netmap_attach_ext(arg, sizeof(struct netmap_pt_guest_adapter), 1);
if (error)
return error;
/* get the netmap_pt_guest_adapter */
ptna = (struct netmap_pt_guest_adapter *) NA(ifp);
/* Initialize a separate pass-through netmap adapter that is going to
* be used by the ptnet driver only, and so never exposed to netmap
* applications. We only need a subset of the available fields. */
memset(&ptna->dr, 0, sizeof(ptna->dr));
ptna->dr.up.ifp = ifp;
ptna->dr.up.nm_mem = netmap_mem_get(ptna->hwup.up.nm_mem);
ptna->dr.up.nm_config = ptna->hwup.up.nm_config;
ptna->backend_regifs = 0;
return 0;
}
#endif /* WITH_PTNETMAP_GUEST */