NetBSD-5.0.2/sys/arch/xen/xen/xennetback_xenbus.c
/* $NetBSD: xennetback_xenbus.c,v 1.24 2008/10/24 18:02:58 jym Exp $ */
/*
* Copyright (c) 2006 Manuel Bouyer.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Manuel Bouyer.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*
*/
#include "opt_xen.h"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/queue.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/device.h>
#include <sys/intr.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/netisr.h>
#include "bpfilter.h"
#if NBPFILTER > 0
#include <net/bpf.h>
#include <net/bpfdesc.h>
#endif
#include <net/if_ether.h>
#include <xen/xen.h>
#include <xen/xen_shm.h>
#include <xen/evtchn.h>
#include <xen/xenbus.h>
#include <xen/xennet_checksum.h>
#include <uvm/uvm.h>
#ifdef XENDEBUG_NET
#define XENPRINTF(x) printf x
#else
#define XENPRINTF(x)
#endif
#define NET_TX_RING_SIZE __RING_SIZE((netif_tx_sring_t *)0, PAGE_SIZE)
#define NET_RX_RING_SIZE __RING_SIZE((netif_rx_sring_t *)0, PAGE_SIZE)
/* linux wants at last 16 bytes free in front of the packet */
#define LINUX_REQUESTED_OFFSET 16
/* hash list for TX requests */
/* descriptor of a packet being handled by the kernel */
struct xni_pkt {
int pkt_id; /* packet's ID */
grant_handle_t pkt_handle;
struct xnetback_instance *pkt_xneti; /* pointer back to our softc */
};
static inline void xni_pkt_unmap(struct xni_pkt *, vaddr_t);
/* pools for xni_pkt */
struct pool xni_pkt_pool;
/* ratecheck(9) for pool allocation failures */
struct timeval xni_pool_errintvl = { 30, 0 }; /* 30s, each */
/*
* Backend network device driver for Xen
*/
/* state of a xnetback instance */
typedef enum {CONNECTED, DISCONNECTING, DISCONNECTED} xnetback_state_t;
/* we keep the xnetback instances in a linked list */
struct xnetback_instance {
SLIST_ENTRY(xnetback_instance) next;
struct xenbus_device *xni_xbusd; /* our xenstore entry */
domid_t xni_domid; /* attached to this domain */
uint32_t xni_handle; /* domain-specific handle */
xnetback_state_t xni_status;
void *xni_softintr;
/* network interface stuff */
struct ethercom xni_ec;
struct callout xni_restart;
uint8_t xni_enaddr[ETHER_ADDR_LEN];
/* remote domain communication stuff */
unsigned int xni_evtchn; /* our even channel */
netif_tx_back_ring_t xni_txring;
netif_rx_back_ring_t xni_rxring;
grant_handle_t xni_tx_ring_handle; /* to unmap the ring */
grant_handle_t xni_rx_ring_handle;
vaddr_t xni_tx_ring_va; /* to unmap the ring */
vaddr_t xni_rx_ring_va;
};
#define xni_if xni_ec.ec_if
#define xni_bpf xni_if.if_bpf
void xvifattach(int);
static int xennetback_ifioctl(struct ifnet *, u_long, void *);
static void xennetback_ifstart(struct ifnet *);
static void xennetback_ifsoftstart(void *);
static void xennetback_ifwatchdog(struct ifnet *);
static int xennetback_ifinit(struct ifnet *);
static void xennetback_ifstop(struct ifnet *, int);
static int xennetback_xenbus_create(struct xenbus_device *);
static int xennetback_xenbus_destroy(void *);
static void xennetback_frontend_changed(void *, XenbusState);
static inline void xennetback_tx_response(struct xnetback_instance *,
int, int);
static void xennetback_tx_free(struct mbuf * , void *, size_t, void *);
SLIST_HEAD(, xnetback_instance) xnetback_instances;
static struct xnetback_instance *xnetif_lookup(domid_t, uint32_t);
static int xennetback_evthandler(void *);
static struct xenbus_backend_driver xvif_backend_driver = {
.xbakd_create = xennetback_xenbus_create,
.xbakd_type = "vif"
};
/*
* Number of packets to transmit in one hypercall (= number of pages to
* transmit at once).
*/
#define NB_XMIT_PAGES_BATCH 64
/*
* We will transfers a mapped page to the remote domain, and remap another
* page in place immediatly. For this we keep a list of pages available.
* When the list is empty, we ask the hypervisor to give us
* NB_XMIT_PAGES_BATCH pages back.
*/
static unsigned long mcl_pages[NB_XMIT_PAGES_BATCH]; /* our physical pages */
int mcl_pages_alloc; /* current index in mcl_pages */
static int xennetback_get_mcl_page(paddr_t *);
static void xennetback_get_new_mcl_pages(void);
/*
* If we can't transfer the mbuf directly, we have to copy it to a page which
* will be transfered to the remote domain. We use a pool_cache
* for this, or the mbuf cluster pool cache if MCLBYTES == PAGE_SIZE
*/
#if MCLBYTES != PAGE_SIZE
pool_cache_t xmit_pages_cache;
#endif
pool_cache_t xmit_pages_cachep;
/* arrays used in xennetback_ifstart(), too large to allocate on stack */
static mmu_update_t xstart_mmu[NB_XMIT_PAGES_BATCH];
static multicall_entry_t xstart_mcl[NB_XMIT_PAGES_BATCH + 1];
static gnttab_transfer_t xstart_gop[NB_XMIT_PAGES_BATCH];
struct mbuf *mbufs_sent[NB_XMIT_PAGES_BATCH];
struct _pages_pool_free {
vaddr_t va;
paddr_t pa;
} pages_pool_free[NB_XMIT_PAGES_BATCH];
static inline void
xni_pkt_unmap(struct xni_pkt *pkt, vaddr_t pkt_va)
{
xen_shm_unmap(pkt_va, 1, &pkt->pkt_handle);
pool_put(&xni_pkt_pool, pkt);
}
void
xvifattach(int n)
{
int i;
struct pglist mlist;
struct vm_page *pg;
XENPRINTF(("xennetback_init\n"));
/*
* steal some non-managed pages to the VM system, to remplace
* mbuf cluster or xmit_pages_pool pages given to foreing domains.
*/
if (uvm_pglistalloc(PAGE_SIZE * NB_XMIT_PAGES_BATCH, 0, 0xffffffff,
0, 0, &mlist, NB_XMIT_PAGES_BATCH, 0) != 0)
panic("xennetback_init: uvm_pglistalloc");
for (i = 0, pg = mlist.tqh_first; pg != NULL;
pg = pg->pageq.queue.tqe_next, i++)
mcl_pages[i] = xpmap_ptom(VM_PAGE_TO_PHYS(pg)) >> PAGE_SHIFT;
if (i != NB_XMIT_PAGES_BATCH)
panic("xennetback_init: %d mcl pages", i);
mcl_pages_alloc = NB_XMIT_PAGES_BATCH - 1;
/* initialise pools */
pool_init(&xni_pkt_pool, sizeof(struct xni_pkt), 0, 0, 0,
"xnbpkt", NULL, IPL_VM);
#if MCLBYTES != PAGE_SIZE
xmit_pages_cache = pool_cache_init(PAGE_SIZE, 0, 0, 0, "xnbxm", NULL,
IPL_VM, NULL, NULL, NULL);
xmit_pages_cachep = xmit_pages_cache;
#else
xmit_pages_cachep = mcl_cache;
#endif
SLIST_INIT(&xnetback_instances);
xenbus_backend_register(&xvif_backend_driver);
}
static int
xennetback_xenbus_create(struct xenbus_device *xbusd)
{
struct xnetback_instance *xneti;
long domid, handle;
struct ifnet *ifp;
extern int ifqmaxlen; /* XXX */
char *val, *e, *p;
int i, err;
if ((err = xenbus_read_ul(NULL, xbusd->xbusd_path,
"frontend-id", &domid, 10)) != 0) {
aprint_error("xvif: can' read %s/frontend-id: %d\n",
xbusd->xbusd_path, err);
return err;
}
if ((err = xenbus_read_ul(NULL, xbusd->xbusd_path,
"handle", &handle, 10)) != 0) {
aprint_error("xvif: can' read %s/handle: %d\n",
xbusd->xbusd_path, err);
return err;
}
if (xnetif_lookup(domid, handle) != NULL) {
return EEXIST;
}
xneti = malloc(sizeof(struct xnetback_instance), M_DEVBUF,
M_NOWAIT | M_ZERO);
if (xneti == NULL) {
return ENOMEM;
}
xneti->xni_domid = domid;
xneti->xni_handle = handle;
xneti->xni_status = DISCONNECTED;
xbusd->xbusd_u.b.b_cookie = xneti;
xbusd->xbusd_u.b.b_detach = xennetback_xenbus_destroy;
xneti->xni_xbusd = xbusd;
xneti->xni_softintr = softint_establish(SOFTINT_NET,
xennetback_ifsoftstart, xneti);
if (xneti->xni_softintr == NULL) {
err = ENOMEM;
goto fail;
}
ifp = &xneti->xni_if;
ifp->if_softc = xneti;
/* read mac address */
if ((err = xenbus_read(NULL, xbusd->xbusd_path, "mac", NULL, &val))) {
aprint_error("xvif: can' read %s/mac: %d\n",
xbusd->xbusd_path, err);
goto fail;
}
for (i = 0, p = val; i < 6; i++) {
xneti->xni_enaddr[i] = strtoul(p, &e, 16);
if ((e[0] == '\0' && i != 5) && e[0] != ':') {
aprint_error("xvif: %s is not a valid mac address\n",
val);
err = EINVAL;
goto fail;
}
p = &e[1];
}
free(val, M_DEVBUF);
/* we can't use the same MAC addr as our guest */
xneti->xni_enaddr[3]++;
/* create pseudo-interface */
snprintf(xneti->xni_if.if_xname, IFNAMSIZ, "xvif%d.%d",
(int)domid, (int)handle);
aprint_verbose_ifnet(ifp, "Ethernet address %s\n",
ether_sprintf(xneti->xni_enaddr));
ifp->if_flags =
IFF_BROADCAST|IFF_SIMPLEX|IFF_NOTRAILERS|IFF_MULTICAST;
ifp->if_snd.ifq_maxlen =
max(ifqmaxlen, NET_TX_RING_SIZE * 2);
ifp->if_capabilities = IFCAP_CSUM_TCPv4_Tx | IFCAP_CSUM_UDPv4_Tx;
ifp->if_ioctl = xennetback_ifioctl;
ifp->if_start = xennetback_ifstart;
ifp->if_watchdog = xennetback_ifwatchdog;
ifp->if_init = xennetback_ifinit;
ifp->if_stop = xennetback_ifstop;
ifp->if_timer = 0;
IFQ_SET_READY(&ifp->if_snd);
if_attach(ifp);
ether_ifattach(&xneti->xni_if, xneti->xni_enaddr);
SLIST_INSERT_HEAD(&xnetback_instances, xneti, next);
xbusd->xbusd_otherend_changed = xennetback_frontend_changed;
err = xenbus_switch_state(xbusd, NULL, XenbusStateInitWait);
if (err) {
printf("failed to switch state on %s: %d\n",
xbusd->xbusd_path, err);
goto fail;
}
if (err) {
printf("failed to write %s/hotplug-status: %d\n",
xbusd->xbusd_path, err);
goto fail;
}
return 0;
fail:
free(xneti, M_DEVBUF);
return err;
}
int
xennetback_xenbus_destroy(void *arg)
{
struct xnetback_instance *xneti = arg;
struct gnttab_unmap_grant_ref op;
int err;
#if 0
if (xneti->xni_status == CONNECTED) {
return EBUSY;
}
#endif
aprint_verbose_ifnet(&xneti->xni_if, "disconnecting\n");
hypervisor_mask_event(xneti->xni_evtchn);
event_remove_handler(xneti->xni_evtchn, xennetback_evthandler, xneti);
softint_disestablish(xneti->xni_softintr);
SLIST_REMOVE(&xnetback_instances,
xneti, xnetback_instance, next);
ether_ifdetach(&xneti->xni_if);
if_detach(&xneti->xni_if);
if (xneti->xni_txring.sring) {
op.host_addr = xneti->xni_tx_ring_va;
op.handle = xneti->xni_tx_ring_handle;
op.dev_bus_addr = 0;
err = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref,
&op, 1);
if (err)
aprint_error_ifnet(&xneti->xni_if,
"unmap_grant_ref failed: %d\n", err);
}
if (xneti->xni_rxring.sring) {
op.host_addr = xneti->xni_rx_ring_va;
op.handle = xneti->xni_rx_ring_handle;
op.dev_bus_addr = 0;
err = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref,
&op, 1);
if (err)
aprint_error_ifnet(&xneti->xni_if,
"unmap_grant_ref failed: %d\n", err);
}
uvm_km_free(kernel_map, xneti->xni_tx_ring_va,
PAGE_SIZE, UVM_KMF_VAONLY);
uvm_km_free(kernel_map, xneti->xni_rx_ring_va,
PAGE_SIZE, UVM_KMF_VAONLY);
free(xneti, M_DEVBUF);
return 0;
}
static void
xennetback_frontend_changed(void *arg, XenbusState new_state)
{
struct xnetback_instance *xneti = arg;
struct xenbus_device *xbusd = xneti->xni_xbusd;
int err;
netif_tx_sring_t *tx_ring;
netif_rx_sring_t *rx_ring;
struct gnttab_map_grant_ref op;
evtchn_op_t evop;
u_long tx_ring_ref, rx_ring_ref;
u_long revtchn;
XENPRINTF(("%s: new state %d\n", xneti->xni_if.if_xname, new_state));
switch(new_state) {
case XenbusStateInitialising:
case XenbusStateInitialised:
break;
case XenbusStateConnected:
/* read comunication informations */
err = xenbus_read_ul(NULL, xbusd->xbusd_otherend,
"tx-ring-ref", &tx_ring_ref, 10);
if (err) {
xenbus_dev_fatal(xbusd, err, "reading %s/tx-ring-ref",
xbusd->xbusd_otherend);
break;
}
err = xenbus_read_ul(NULL, xbusd->xbusd_otherend,
"rx-ring-ref", &rx_ring_ref, 10);
if (err) {
xenbus_dev_fatal(xbusd, err, "reading %s/rx-ring-ref",
xbusd->xbusd_otherend);
break;
}
err = xenbus_read_ul(NULL, xbusd->xbusd_otherend,
"event-channel", &revtchn, 10);
if (err) {
xenbus_dev_fatal(xbusd, err, "reading %s/event-channel",
xbusd->xbusd_otherend);
break;
}
/* allocate VA space and map rings */
xneti->xni_tx_ring_va = uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
UVM_KMF_VAONLY);
if (xneti->xni_tx_ring_va == 0) {
xenbus_dev_fatal(xbusd, ENOMEM,
"can't get VA for tx ring", xbusd->xbusd_otherend);
break;
}
tx_ring = (void *)xneti->xni_tx_ring_va;
xneti->xni_rx_ring_va = uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
UVM_KMF_VAONLY);
if (xneti->xni_rx_ring_va == 0) {
xenbus_dev_fatal(xbusd, ENOMEM,
"can't get VA for rx ring", xbusd->xbusd_otherend);
goto err1;
}
rx_ring = (void *)xneti->xni_rx_ring_va;
op.host_addr = xneti->xni_tx_ring_va;
op.flags = GNTMAP_host_map;
op.ref = tx_ring_ref;
op.dom = xneti->xni_domid;
err = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1);
if (err || op.status) {
printf("%s: can't map TX grant ref: %d/%d\n",
xneti->xni_if.if_xname, err, op.status);
goto err2;
}
xneti->xni_tx_ring_handle = op.handle;
op.host_addr = xneti->xni_rx_ring_va;
op.flags = GNTMAP_host_map;
op.ref = rx_ring_ref;
op.dom = xneti->xni_domid;
err = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1);
if (err || op.status) {
printf("%s: can't map RX grant ref: %d/%d\n",
xneti->xni_if.if_xname, err, op.status);
goto err2;
}
xneti->xni_rx_ring_handle = op.handle;
BACK_RING_INIT(&xneti->xni_txring, tx_ring, PAGE_SIZE);
BACK_RING_INIT(&xneti->xni_rxring, rx_ring, PAGE_SIZE);
evop.cmd = EVTCHNOP_bind_interdomain;
evop.u.bind_interdomain.remote_dom = xneti->xni_domid;
evop.u.bind_interdomain.remote_port = revtchn;
err = HYPERVISOR_event_channel_op(&evop);
if (err) {
printf("%s: can't get event channel: %d\n",
xneti->xni_if.if_xname, err);
goto err2;
}
xneti->xni_evtchn = evop.u.bind_interdomain.local_port;
x86_sfence();
xneti->xni_status = CONNECTED;
xenbus_switch_state(xbusd, NULL, XenbusStateConnected);
x86_sfence();
event_set_handler(xneti->xni_evtchn, xennetback_evthandler,
xneti, IPL_NET, xneti->xni_if.if_xname);
xennetback_ifinit(&xneti->xni_if);
hypervisor_enable_event(xneti->xni_evtchn);
hypervisor_notify_via_evtchn(xneti->xni_evtchn);
break;
case XenbusStateClosing:
xneti->xni_status = DISCONNECTING;
xneti->xni_if.if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
xneti->xni_if.if_timer = 0;
xenbus_switch_state(xbusd, NULL, XenbusStateClosing);
break;
case XenbusStateClosed:
/* otherend_changed() should handle it for us */
panic("xennetback_frontend_changed: closed\n");
case XenbusStateUnknown:
case XenbusStateInitWait:
default:
aprint_error("%s: invalid frontend state %d\n",
xneti->xni_if.if_xname, new_state);
break;
}
return;
err2:
uvm_km_free(kernel_map, xneti->xni_rx_ring_va,
PAGE_SIZE, UVM_KMF_VAONLY);
err1:
uvm_km_free(kernel_map, xneti->xni_tx_ring_va,
PAGE_SIZE, UVM_KMF_VAONLY);
}
/* lookup a xneti based on domain id and interface handle */
static struct xnetback_instance *
xnetif_lookup(domid_t dom , uint32_t handle)
{
struct xnetback_instance *xneti;
SLIST_FOREACH(xneti, &xnetback_instances, next) {
if (xneti->xni_domid == dom && xneti->xni_handle == handle)
return xneti;
}
return NULL;
}
/* get a page to remplace a mbuf cluster page given to a domain */
static int
xennetback_get_mcl_page(paddr_t *map)
{
if (mcl_pages_alloc < 0)
/*
* we exhausted our allocation. We can't allocate new ones yet
* because the current pages may not have been loaned to
* the remote domain yet. We have to let the caller do this.
*/
return -1;
*map = mcl_pages[mcl_pages_alloc] << PAGE_SHIFT;
mcl_pages_alloc--;
return 0;
}
static void
xennetback_get_new_mcl_pages(void)
{
int nb_pages;
struct xen_memory_reservation res;
/* get some new pages. */
res.extent_start = mcl_pages;
res.nr_extents = NB_XMIT_PAGES_BATCH;
res.extent_order = 0;
res.address_bits = 0;
res.domid = DOMID_SELF;
nb_pages = HYPERVISOR_memory_op(XENMEM_increase_reservation, &res);
if (nb_pages <= 0) {
printf("xennetback: can't get new mcl pages (%d)\n", nb_pages);
return;
}
if (nb_pages != NB_XMIT_PAGES_BATCH)
printf("xennetback: got only %d new mcl pages\n", nb_pages);
mcl_pages_alloc = nb_pages - 1;
}
static inline void
xennetback_tx_response(struct xnetback_instance *xneti, int id, int status)
{
RING_IDX resp_prod;
netif_tx_response_t *txresp;
int do_event;
resp_prod = xneti->xni_txring.rsp_prod_pvt;
txresp = RING_GET_RESPONSE(&xneti->xni_txring, resp_prod);
txresp->id = id;
txresp->status = status;
xneti->xni_txring.rsp_prod_pvt++;
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&xneti->xni_txring, do_event);
if (do_event) {
XENPRINTF(("%s send event\n", xneti->xni_if.if_xname));
hypervisor_notify_via_evtchn(xneti->xni_evtchn);
}
}
static int
xennetback_evthandler(void *arg)
{
struct xnetback_instance *xneti = arg;
struct ifnet *ifp = &xneti->xni_if;
netif_tx_request_t *txreq;
struct xni_pkt *pkt;
vaddr_t pkt_va;
struct mbuf *m;
int receive_pending, err;
RING_IDX req_cons;
XENPRINTF(("xennetback_evthandler "));
req_cons = xneti->xni_txring.req_cons;
x86_lfence();
while (1) {
x86_lfence(); /* be sure to read the request before updating */
xneti->xni_txring.req_cons = req_cons;
x86_sfence();
RING_FINAL_CHECK_FOR_REQUESTS(&xneti->xni_txring,
receive_pending);
if (receive_pending == 0)
break;
txreq = RING_GET_REQUEST(&xneti->xni_txring, req_cons);
x86_lfence();
XENPRINTF(("%s pkt size %d\n", xneti->xni_if.if_xname,
txreq->size));
req_cons++;
if (__predict_false((ifp->if_flags & (IFF_UP | IFF_RUNNING)) !=
(IFF_UP | IFF_RUNNING))) {
/* interface not up, drop */
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_DROPPED);
continue;
}
/*
* Do some sanity checks, and map the packet's page.
*/
if (__predict_false(txreq->size < ETHER_HDR_LEN ||
txreq->size > (ETHER_MAX_LEN - ETHER_CRC_LEN))) {
printf("%s: packet size %d too big\n",
ifp->if_xname, txreq->size);
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_ERROR);
ifp->if_ierrors++;
continue;
}
/* don't cross page boundaries */
if (__predict_false(
txreq->offset + txreq->size > PAGE_SIZE)) {
printf("%s: packet cross page boundary\n",
ifp->if_xname);
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_ERROR);
ifp->if_ierrors++;
continue;
}
/* get a mbuf for this packet */
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (__predict_false(m == NULL)) {
static struct timeval lasttime;
if (ratecheck(&lasttime, &xni_pool_errintvl))
printf("%s: mbuf alloc failed\n",
ifp->if_xname);
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_DROPPED);
ifp->if_ierrors++;
continue;
}
XENPRINTF(("%s pkt offset %d size %d id %d req_cons %d\n",
xneti->xni_if.if_xname, txreq->offset,
txreq->size, txreq->id, MASK_NETIF_TX_IDX(req_cons)));
pkt = pool_get(&xni_pkt_pool, PR_NOWAIT);
if (__predict_false(pkt == NULL)) {
static struct timeval lasttime;
if (ratecheck(&lasttime, &xni_pool_errintvl))
printf("%s: xnbpkt alloc failed\n",
ifp->if_xname);
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_DROPPED);
ifp->if_ierrors++;
m_freem(m);
continue;
}
err = xen_shm_map(1, xneti->xni_domid, &txreq->gref, &pkt_va,
&pkt->pkt_handle, XSHM_RO);
if (__predict_false(err == ENOMEM)) {
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_DROPPED);
ifp->if_ierrors++;
pool_put(&xni_pkt_pool, pkt);
m_freem(m);
continue;
}
if (__predict_false(err)) {
printf("%s: mapping foreing page failed: %d\n",
xneti->xni_if.if_xname, err);
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_ERROR);
ifp->if_ierrors++;
pool_put(&xni_pkt_pool, pkt);
m_freem(m);
continue;
}
if ((ifp->if_flags & IFF_PROMISC) == 0) {
struct ether_header *eh =
(void*)(pkt_va + txreq->offset);
if (ETHER_IS_MULTICAST(eh->ether_dhost) == 0 &&
memcmp(CLLADDR(ifp->if_sadl), eh->ether_dhost,
ETHER_ADDR_LEN) != 0) {
xni_pkt_unmap(pkt, pkt_va);
m_freem(m);
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_OKAY);
continue; /* packet is not for us */
}
}
#ifdef notyet
a lot of work is needed in the tcp stack to handle read-only ext storage
so always copy for now.
if (((req_cons + 1) & (NET_TX_RING_SIZE - 1)) ==
(xneti->xni_txring.rsp_prod_pvt & (NET_TX_RING_SIZE - 1)))
#else
if (1)
#endif /* notyet */
{
/*
* This is the last TX buffer. Copy the data and
* ack it. Delaying it until the mbuf is
* freed will stall transmit.
*/
m->m_len = min(MHLEN, txreq->size);
m->m_pkthdr.len = 0;
m_copyback(m, 0, txreq->size,
(void *)(pkt_va + txreq->offset));
xni_pkt_unmap(pkt, pkt_va);
if (m->m_pkthdr.len < txreq->size) {
ifp->if_ierrors++;
m_freem(m);
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_DROPPED);
continue;
}
xennetback_tx_response(xneti, txreq->id,
NETIF_RSP_OKAY);
} else {
pkt->pkt_id = txreq->id;
pkt->pkt_xneti = xneti;
MEXTADD(m, pkt_va + txreq->offset,
txreq->size, M_DEVBUF, xennetback_tx_free, pkt);
m->m_pkthdr.len = m->m_len = txreq->size;
m->m_flags |= M_EXT_ROMAP;
}
if ((txreq->flags & NETTXF_csum_blank) != 0) {
xennet_checksum_fill(&m);
if (m == NULL) {
ifp->if_ierrors++;
continue;
}
}
m->m_pkthdr.rcvif = ifp;
ifp->if_ipackets++;
#if NBPFILTER > 0
if (ifp->if_bpf)
bpf_mtap(ifp->if_bpf, m);
#endif
(*ifp->if_input)(ifp, m);
}
x86_lfence(); /* be sure to read the request before updating pointer */
xneti->xni_txring.req_cons = req_cons;
x86_sfence();
/* check to see if we can transmit more packets */
softint_schedule(xneti->xni_softintr);
return 1;
}
static void
xennetback_tx_free(struct mbuf *m, void *va, size_t size, void *arg)
{
int s = splnet();
struct xni_pkt *pkt = arg;
struct xnetback_instance *xneti = pkt->pkt_xneti;
XENPRINTF(("xennetback_tx_free\n"));
xennetback_tx_response(xneti, pkt->pkt_id, NETIF_RSP_OKAY);
xni_pkt_unmap(pkt, (vaddr_t)va & ~PAGE_MASK);
if (m)
pool_cache_put(mb_cache, m);
splx(s);
}
static int
xennetback_ifioctl(struct ifnet *ifp, u_long cmd, void *data)
{
//struct xnetback_instance *xneti = ifp->if_softc;
//struct ifreq *ifr = (struct ifreq *)data;
int s, error;
s = splnet();
error = ether_ioctl(ifp, cmd, data);
if (error == ENETRESET)
error = 0;
splx(s);
return error;
}
static void
xennetback_ifstart(struct ifnet *ifp)
{
struct xnetback_instance *xneti = ifp->if_softc;
/*
* The Xen communication channel is much more efficient if we can
* schedule batch of packets for the domain. To achieve this, we
* schedule a soft interrupt, and just return. This way, the network
* stack will enqueue all pending mbufs in the interface's send queue
* before it is processed by xennet_softstart().
*/
softint_schedule(xneti->xni_softintr);
}
static void
xennetback_ifsoftstart(void *arg)
{
struct xnetback_instance *xneti = arg;
struct ifnet *ifp = &xneti->xni_if;
struct mbuf *m;
vaddr_t xmit_va;
paddr_t xmit_pa;
paddr_t xmit_ma;
paddr_t newp_ma = 0; /* XXX gcc */
int i, j, nppitems;
mmu_update_t *mmup;
multicall_entry_t *mclp;
netif_rx_response_t *rxresp;
RING_IDX req_prod, resp_prod;
int do_event = 0;
gnttab_transfer_t *gop;
int id, offset;
XENPRINTF(("xennetback_ifsoftstart "));
int s = splnet();
if (__predict_false(
(ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)) {
splx(s);
return;
}
while (!IFQ_IS_EMPTY(&ifp->if_snd)) {
XENPRINTF(("pkt\n"));
req_prod = xneti->xni_rxring.sring->req_prod;
resp_prod = xneti->xni_rxring.rsp_prod_pvt;
x86_lfence();
mmup = xstart_mmu;
mclp = xstart_mcl;
gop = xstart_gop;
for (nppitems = 0, i = 0; !IFQ_IS_EMPTY(&ifp->if_snd);) {
XENPRINTF(("have a packet\n"));
IFQ_POLL(&ifp->if_snd, m);
if (__predict_false(m == NULL))
panic("xennetback_ifstart: IFQ_POLL");
if (__predict_false(
req_prod == xneti->xni_rxring.req_cons ||
xneti->xni_rxring.req_cons - resp_prod ==
NET_RX_RING_SIZE)) {
/* out of ring space */
XENPRINTF(("xennetback_ifstart: ring full "
"req_prod 0x%x req_cons 0x%x resp_prod "
"0x%x\n",
req_prod, xneti->xni_rxring.req_cons,
resp_prod));
ifp->if_timer = 1;
break;
}
if (__predict_false(i == NB_XMIT_PAGES_BATCH))
break; /* we filled the array */
if (__predict_false(
xennetback_get_mcl_page(&newp_ma) != 0))
break; /* out of memory */
if ((m->m_flags & M_CLUSTER) != 0 &&
!M_READONLY(m) && MCLBYTES == PAGE_SIZE) {
/* we can give this page away */
xmit_pa = m->m_ext.ext_paddr;
xmit_ma = xpmap_ptom(xmit_pa);
xmit_va = (vaddr_t)m->m_ext.ext_buf;
KASSERT(xmit_pa != M_PADDR_INVALID);
KASSERT((xmit_va & PAGE_MASK) == 0);
offset = m->m_data - m->m_ext.ext_buf;
} else {
/* we have to copy the packet */
xmit_va = (vaddr_t)pool_cache_get_paddr(
xmit_pages_cachep,
PR_NOWAIT, &xmit_pa);
if (__predict_false(xmit_va == 0))
break; /* out of memory */
KASSERT(xmit_pa != POOL_PADDR_INVALID);
xmit_ma = xpmap_ptom(xmit_pa);
XENPRINTF(("xennetback_get_xmit_page: got va "
"0x%x ma 0x%x\n", (u_int)xmit_va,
(u_int)xmit_ma));
m_copydata(m, 0, m->m_pkthdr.len,
(char *)xmit_va + LINUX_REQUESTED_OFFSET);
offset = LINUX_REQUESTED_OFFSET;
pages_pool_free[nppitems].va = xmit_va;
pages_pool_free[nppitems].pa = xmit_pa;
nppitems++;
}
/* start filling ring */
gop->ref = RING_GET_REQUEST(&xneti->xni_rxring,
xneti->xni_rxring.req_cons)->gref;
id = RING_GET_REQUEST(&xneti->xni_rxring,
xneti->xni_rxring.req_cons)->id;
x86_lfence();
xneti->xni_rxring.req_cons++;
rxresp = RING_GET_RESPONSE(&xneti->xni_rxring,
resp_prod);
rxresp->id = id;
rxresp->offset = offset;
rxresp->status = m->m_pkthdr.len;
if ((m->m_pkthdr.csum_flags &
(M_CSUM_TCPv4 | M_CSUM_UDPv4)) != 0) {
rxresp->flags = NETRXF_csum_blank;
} else {
rxresp->flags = 0;
}
/*
* transfers the page containing the packet to the
* remote domain, and map newp in place.
*/
xpmap_phys_to_machine_mapping[
(xmit_pa - XPMAP_OFFSET) >> PAGE_SHIFT] =
newp_ma >> PAGE_SHIFT;
MULTI_update_va_mapping(mclp, xmit_va,
newp_ma | PG_V | PG_RW | PG_U | PG_M, 0);
mclp++;
gop->mfn = xmit_ma >> PAGE_SHIFT;
gop->domid = xneti->xni_domid;
gop++;
mmup->ptr = newp_ma | MMU_MACHPHYS_UPDATE;
mmup->val = (xmit_pa - XPMAP_OFFSET) >> PAGE_SHIFT;
mmup++;
/* done with this packet */
IFQ_DEQUEUE(&ifp->if_snd, m);
mbufs_sent[i] = m;
resp_prod++;
i++; /* this packet has been queued */
ifp->if_opackets++;
#if NBPFILTER > 0
if (ifp->if_bpf)
bpf_mtap(ifp->if_bpf, m);
#endif
}
if (i != 0) {
/*
* We may have allocated buffers which have entries
* outstanding in the page update queue -- make sure
* we flush those first!
*/
int svm = splvm();
xpq_flush_queue();
splx(svm);
mclp[-1].args[MULTI_UVMFLAGS_INDEX] =
UVMF_TLB_FLUSH|UVMF_ALL;
mclp->op = __HYPERVISOR_mmu_update;
mclp->args[0] = (unsigned long)xstart_mmu;
mclp->args[1] = i;
mclp->args[2] = 0;
mclp->args[3] = DOMID_SELF;
mclp++;
/* update the MMU */
if (HYPERVISOR_multicall(xstart_mcl, i + 1) != 0) {
panic("%s: HYPERVISOR_multicall failed",
ifp->if_xname);
}
for (j = 0; j < i + 1; j++) {
if (xstart_mcl[j].result != 0) {
printf("%s: xstart_mcl[%d] "
"failed (%lu)\n", ifp->if_xname,
j, xstart_mcl[j].result);
printf("%s: req_prod %u req_cons "
"%u rsp_prod %u rsp_prod_pvt %u "
"i %u\n",
ifp->if_xname,
xneti->xni_rxring.sring->req_prod,
xneti->xni_rxring.req_cons,
xneti->xni_rxring.sring->rsp_prod,
xneti->xni_rxring.rsp_prod_pvt,
i);
}
}
if (HYPERVISOR_grant_table_op(GNTTABOP_transfer,
xstart_gop, i) != 0) {
panic("%s: GNTTABOP_transfer failed",
ifp->if_xname);
}
for (j = 0; j < i; j++) {
if (xstart_gop[j].status != 0) {
printf("%s GNTTABOP_transfer[%d] %d\n",
ifp->if_xname,
j, xstart_gop[j].status);
printf("%s: req_prod %u req_cons "
"%u rsp_prod %u rsp_prod_pvt %u "
"i %d\n",
ifp->if_xname,
xneti->xni_rxring.sring->req_prod,
xneti->xni_rxring.req_cons,
xneti->xni_rxring.sring->rsp_prod,
xneti->xni_rxring.rsp_prod_pvt,
i);
rxresp = RING_GET_RESPONSE(
&xneti->xni_rxring,
xneti->xni_rxring.rsp_prod_pvt + j);
rxresp->status = NETIF_RSP_ERROR;
}
}
/* update pointer */
KASSERT(
xneti->xni_rxring.rsp_prod_pvt + i == resp_prod);
xneti->xni_rxring.rsp_prod_pvt = resp_prod;
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(
&xneti->xni_rxring, j);
if (j)
do_event = 1;
/* now we can free the mbufs */
for (j = 0; j < i; j++) {
m_freem(mbufs_sent[j]);
}
for (j = 0; j < nppitems; j++) {
pool_cache_put_paddr(xmit_pages_cachep,
(void *)pages_pool_free[j].va,
pages_pool_free[j].pa);
}
}
/* send event */
if (do_event) {
x86_lfence();
XENPRINTF(("%s receive event\n",
xneti->xni_if.if_xname));
hypervisor_notify_via_evtchn(xneti->xni_evtchn);
do_event = 0;
}
/* check if we need to get back some pages */
if (mcl_pages_alloc < 0) {
xennetback_get_new_mcl_pages();
if (mcl_pages_alloc < 0) {
/*
* setup the watchdog to try again, because
* xennetback_ifstart() will never be called
* again if queue is full.
*/
printf("xennetback_ifstart: no mcl_pages\n");
ifp->if_timer = 1;
break;
}
}
/*
* note that we don't use RING_FINAL_CHECK_FOR_REQUESTS()
* here, as the frontend doesn't notify when adding
* requests anyway
*/
if (__predict_false(
!RING_HAS_UNCONSUMED_REQUESTS(&xneti->xni_rxring))) {
/* ring full */
break;
}
}
splx(s);
}
static void
xennetback_ifwatchdog(struct ifnet * ifp)
{
/*
* We can get to the following condition:
* transmit stalls because the ring is full when the ifq is full too.
* In this case (as, unfortunably, we don't get an interrupt from xen
* on transmit) noting will ever call xennetback_ifstart() again.
* Here we abuse the watchdog to get out of this condition.
*/
XENPRINTF(("xennetback_ifwatchdog\n"));
xennetback_ifstart(ifp);
}
static int
xennetback_ifinit(struct ifnet *ifp)
{
struct xnetback_instance *xneti = ifp->if_softc;
int s = splnet();
if ((ifp->if_flags & IFF_UP) == 0) {
splx(s);
return 0;
}
if (xneti->xni_status == CONNECTED)
ifp->if_flags |= IFF_RUNNING;
splx(s);
return 0;
}
static void
xennetback_ifstop(struct ifnet *ifp, int disable)
{
struct xnetback_instance *xneti = ifp->if_softc;
int s = splnet();
ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
ifp->if_timer = 0;
if (xneti->xni_status == CONNECTED) {
XENPRINTF(("%s: req_prod 0x%x resp_prod 0x%x req_cons 0x%x "
"event 0x%x\n", ifp->if_xname, xneti->xni_txring->req_prod,
xneti->xni_txring->resp_prod, xneti->xni_txring->req_cons,
xneti->xni_txring->event));
xennetback_evthandler(ifp->if_softc); /* flush pending RX requests */
}
splx(s);
}