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/*
* Xen virtual network interface frontend
*/
#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "../port/error.h"
#include "../port/netif.h"
#include "../port/etherif.h"
#define LOG(a)
enum {
Nvif = 4,
Ntb = 16,
Nrb = 32,
};
typedef struct Ctlr Ctlr;
typedef union Txframe Txframe;
typedef union Rxframe Rxframe;
struct Ctlr {
int attached;
int backend;
int vifno;
int evtchn;
int rxcopy;
Txframe *txframes;
Txframe *freetxframe;
Rxframe *rxframes;
netif_tx_front_ring_t txring;
netif_rx_front_ring_t rxring;
int *txrefs;
int *rxrefs;
int txringref;
int rxringref;
Lock txlock;
QLock attachlock;
Rendez wtxframe;
Rendez wtxblock;
ulong interrupts;
ulong transmits;
ulong receives;
ulong txerrors;
ulong rxerrors;
ulong rxoverflows;
};
union Txframe {
struct {
Txframe *next;
char data[2];
} tf;
uchar page[BY2PG];
};
union Rxframe {
uchar page[BY2PG];
};
static int nvif;
/*
* conversions to machine page numbers, pages and addresses
*/
#define MFN(pa) (patomfn[(pa)>>PGSHIFT])
#define MFNPG(pa) (MFN(pa)<<PGSHIFT)
#define PA2MA(pa) (MFNPG(pa) | PGOFF(pa))
#define VA2MA(va) PA2MA(PADDR(va))
static int
puttxrequest(Ctlr *ctlr, netif_tx_request_t *tr)
{
netif_tx_request_t *req;
int i, notify;
LOG(dprint("puttxrequest id %d ref %d size %d\n", tr->id, tr->gref, tr->size);)
i = ctlr->txring.req_prod_pvt;
req = RING_GET_REQUEST(&ctlr->txring, i);
memmove(req, tr, sizeof(*req));
ctlr->txring.req_prod_pvt = i+1;
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&ctlr->txring, notify);
return notify;
}
static int
putrxrequest(Ctlr *ctlr, netif_rx_request_t *rr)
{
netif_rx_request_t *req;
int i;
int notify;
LOG(dprint("putrxrequest %d %d\n", rr->id, rr->gref);)
i = ctlr->rxring.req_prod_pvt;
req = RING_GET_REQUEST(&ctlr->rxring, i);
memmove(req, rr, sizeof(*req));
ctlr->rxring.req_prod_pvt = i+1;
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&ctlr->rxring, notify);
return notify;
}
static int
gettxresponse(Ctlr *ctlr, netif_tx_response_t *tr)
{
int i, avail;
netif_tx_response_t *rx;
RING_FINAL_CHECK_FOR_RESPONSES(&ctlr->txring, avail);
if (!avail)
return 0;
i = ctlr->txring.rsp_cons;
rx = RING_GET_RESPONSE(&ctlr->txring, i);
LOG(dprint("gettxresponse id %d status %d\n", rx->id, rx->status);)
if(rx->status)
ctlr->txerrors++;
*tr = *rx;
ctlr->txring.rsp_cons = ++i;
return 1;
}
static int
getrxresponse(Ctlr *ctlr, netif_rx_response_t* rr)
{
int i, avail;
netif_rx_response_t *rx;
RING_FINAL_CHECK_FOR_RESPONSES(&ctlr->rxring, avail);
if (!avail)
return 0;
i = ctlr->rxring.rsp_cons;
rx = RING_GET_RESPONSE(&ctlr->rxring, i);
LOG(dprint("getrxresponse id %d offset %d flags %ux status %d\n", rx->id, rx->offset, rx->flags, rx->status);)
*rr = *rx;
ctlr->rxring.rsp_cons = ++i;
return 1;
}
static int
ringinit(Ctlr *ctlr, char *a)
{
netif_tx_sring_t *txr;
netif_rx_sring_t *rxr;
txr = (netif_tx_sring_t*)a;
memset(txr, 0, BY2PG);
SHARED_RING_INIT(txr);
FRONT_RING_INIT(&ctlr->txring, txr, BY2PG);
ctlr->txringref = shareframe(ctlr->backend, txr, 1);
rxr = (netif_rx_sring_t*)(a+BY2PG);
SHARED_RING_INIT(rxr);
FRONT_RING_INIT(&ctlr->rxring, rxr, BY2PG);
ctlr->rxringref = shareframe(ctlr->backend, rxr, 1);
return 2*BY2PG;
}
static int
vifsend(Ctlr *ctlr, Block *bp)
{
netif_tx_request_t tr;
Txframe *tx;
int id;
ilock(&ctlr->txlock);
tx = ctlr->freetxframe;
ctlr->freetxframe = tx->tf.next;
iunlock(&ctlr->txlock);
id = tx - ctlr->txframes;
tr.gref = ctlr->txrefs[id];
tr.offset = tx->tf.data - (char*)tx;
tr.flags = 0; // XXX checksum?
tr.id = id;
tr.size = BLEN(bp);
memmove(tx->tf.data, bp->rp, tr.size);
return puttxrequest(ctlr, &tr);
}
static int
vifsenddone(Ctlr *ctlr, netif_tx_response_t *tr)
{
Txframe *tx;
tx = &ctlr->txframes[tr->id]; // XXX check validity of id
ilock(&ctlr->txlock);
tx->tf.next = ctlr->freetxframe;
ctlr->freetxframe = tx;
iunlock(&ctlr->txlock);
return 1;
}
static int
vifrecv(Ctlr *ctlr, Rxframe *rx)
{
netif_rx_request_t rr;
int id;
int ref;
id = rx - ctlr->rxframes;
if (ctlr->rxcopy)
ref = ctlr->rxrefs[id];
else {
ref = donateframe(ctlr->backend, rx);
ctlr->rxrefs[id] = ref;
}
rr.id = id;
rr.gref = ref;
return putrxrequest(ctlr, &rr);
}
static int
vifrecvdone(Ether *ether, netif_rx_response_t *rr)
{
Ctlr *ctlr;
Rxframe *rx;
Block *bp;
int len;
ctlr = ether->ctlr;
rx = &ctlr->rxframes[rr->id]; // XXX check validity of id
if (!ctlr->rxcopy)
acceptframe(ctlr->rxrefs[rr->id], rx);
if ((len = rr->status) <= 0) {
ctlr->rxerrors++;
vifrecv(ctlr, rx);
return 1;
}
if(len > sizeof(Etherpkt) || (bp = iallocb(sizeof(Etherpkt))) == nil) {
ctlr->rxoverflows++;
vifrecv(ctlr, rx);
return 1;
}
ctlr->receives++;
memmove(bp->base, rx->page + rr->offset, len);
vifrecv(ctlr, rx);
bp->rp = bp->base;
bp->wp = bp->rp + len;
bp->free = 0;
bp->next = 0;
bp->list = 0;
if (rr->flags & NETRXF_data_validated)
bp->flag |= Btcpck|Budpck;
etheriq(ether, bp);
return 0;
}
static int
wtxframe(void *a)
{
return ((struct Ctlr*)a)->freetxframe != 0;
}
static int
wtxblock(void *a)
{
return qcanread(((struct Ether*)a)->oq);
}
static void
etherxenproc(void *a)
{
Ether *ether = a;
Ctlr *ctlr = ether->ctlr;
Block *bp;
int notify;
for (;;) {
while (ctlr->freetxframe == 0)
sleep(&ctlr->wtxframe, wtxframe, ctlr);
while ((bp = qget(ether->oq)) == 0)
sleep(&ctlr->wtxblock, wtxblock, ether);
notify = vifsend(ctlr, bp);
freeb(bp);
if (notify)
xenchannotify(ctlr->evtchn);
}
}
static void
etherxentransmit(Ether *ether)
{
Ctlr *ctlr;
ctlr = ether->ctlr;
ctlr->transmits++;
wakeup(&ctlr->wtxblock);
}
static void
etherxenintr(Ureg*, void *a)
{
Ether *ether = a;
Ctlr *ctlr = ether->ctlr;
int txnotify;
netif_tx_response_t tr;
netif_rx_response_t rr;
ctlr->interrupts++;
txnotify = 0;
while (getrxresponse(ctlr, &rr))
vifrecvdone(ether, &rr);
while (gettxresponse(ctlr, &tr)) {
if (vifsenddone(ctlr, &tr))
txnotify = 1;
}
if (txnotify)
wakeup(&ctlr->wtxframe);
}
static long
etherxenctl(Ether *ether, void *buf, long n)
{
uchar ea[Eaddrlen];
Cmdbuf *cb;
cb = parsecmd(buf, n);
if(cb->nf >= 2
&& strcmp(cb->f[0], "ea")==0
&& parseether(ea, cb->f[1]) == 0){
free(cb);
memmove(ether->ea, ea, Eaddrlen);
memmove(ether->addr, ether->ea, Eaddrlen);
return 0;
}
free(cb);
error(Ebadctl);
return -1; /* not reached */
}
static void
backendconnect(Ctlr *ctlr)
{
char dir[64];
char buf[64];
sprint(dir, "device/vif/%d/", ctlr->vifno);
xenstore_setd(dir, "state", XenbusStateInitialising);
xenstore_setd(dir, "tx-ring-ref", ctlr->txringref);
xenstore_setd(dir, "rx-ring-ref", ctlr->rxringref);
xenstore_setd(dir, "event-channel", ctlr->evtchn);
print("etherxen: request-rx-copy=%d\n", ctlr->rxcopy);
if (ctlr->rxcopy)
xenstore_setd(dir, "request-rx-copy", 1);
xenstore_setd(dir, "state", XenbusStateConnected);
xenstore_gets(dir, "backend", buf, sizeof buf);
sprint(dir, "%s/", buf);
HYPERVISOR_yield();
xenstore_gets(dir, "state", buf, sizeof buf);
while (strtol(buf, 0, 0) != XenbusStateConnected) {
print("etherxen: waiting for vif %d to connect\n", ctlr->vifno);
tsleep(&up->sleep, return0, 0, 50);
xenstore_gets(dir, "state", buf, sizeof buf);
}
}
static void
etherxenattach(Ether *ether)
{
Ctlr *ctlr;
char *p;
Txframe *tx;
int npage, i;
LOG(dprint("etherxenattach\n");)
ctlr = ether->ctlr;
qlock(&ctlr->attachlock);
if (ctlr->attached) {
qunlock(&ctlr->attachlock);
return;
}
npage = 2 + Ntb + Nrb;
p = (char*)xspanalloc(npage<<PGSHIFT, BY2PG, 0);
p += ringinit(ctlr, p);
ctlr->txrefs = malloc(Ntb*sizeof(int));
ctlr->rxrefs = malloc(Nrb*sizeof(int));
ctlr->txframes = (Txframe*)p;
for (i = 0; i < Ntb; i++, p += BY2PG) {
tx = (Txframe*)p;
if (i != Ntb-1)
tx->tf.next = tx + 1;
else
tx->tf.next = 0;
ctlr->txrefs[i] = shareframe(ctlr->backend, tx, 0);
}
ctlr->freetxframe = ctlr->txframes;
ctlr->rxframes = (Rxframe*)p;
for (i = 0; i < Nrb; i++, p += BY2PG) {
if (ctlr->rxcopy)
ctlr->rxrefs[i] = shareframe(ctlr->backend, (Rxframe*)p, 1);
vifrecv(ctlr, (Rxframe*)p);
}
ctlr->evtchn = xenchanalloc(ctlr->backend);
intrenable(ctlr->evtchn, etherxenintr, ether, BUSUNKNOWN, "vif");
kproc("vif", etherxenproc, ether);
backendconnect(ctlr);
ctlr->attached = 1;
qunlock(&ctlr->attachlock);
}
static void
etherxenmulticast(void* arg, uchar* addr, int on)
{
USED(arg, addr, on);
}
static long
ifstat(Ether* ether, void* a, long n, ulong offset)
{
Ctlr *ctlr;
char *buf, *p;
int l, len;
ctlr = ether->ctlr;
if(n == 0)
return 0;
if((p = malloc(READSTR)) == nil)
error(Enomem);
l = snprint(p, READSTR, "intr: %lud\n", ctlr->interrupts);
l += snprint(p+l, READSTR-l, "transmits: %lud\n", ctlr->transmits);
l += snprint(p+l, READSTR-l, "receives: %lud\n", ctlr->receives);
l += snprint(p+l, READSTR-l, "txerrors: %lud\n", ctlr->txerrors);
l += snprint(p+l, READSTR-l, "rxerrors: %lud\n", ctlr->rxerrors);
snprint(p+l, READSTR-l, "rxoverflows: %lud\n", ctlr->rxoverflows);
buf = a;
len = readstr(offset, buf, n, p);
free(p);
return len;
}
static int
pnp(Ether* ether)
{
uchar ea[Eaddrlen];
char dir[64];
char buf[64];
Ctlr *ctlr;
int domid, rxcopy;
if (nvif > Nvif)
return -1;
sprint(dir, "device/vif/%d/", nvif);
if (xenstore_gets(dir, "backend-id", buf, sizeof buf) <= 0)
return -1;
domid = strtol(buf, 0, 0);
if (xenstore_gets(dir, "mac", buf, sizeof buf) <= 0)
return -1;
if (parseether(ea, buf) < 0)
return -1;
if (xenstore_gets(dir, "backend", buf, sizeof buf) <= 0)
return 1;
sprint(dir, "%s/", buf);
rxcopy = 0;
if (xenstore_gets(dir, "feature-rx-copy", buf, sizeof buf) >= 0)
rxcopy = strtol(buf, 0, 0);
ether->ctlr = ctlr = malloc(sizeof(Ctlr));
memset(ctlr, 0, sizeof(Ctlr));
ctlr->backend = domid;
ctlr->vifno = nvif++;
ctlr->rxcopy = rxcopy;
memmove(ether->ea, ea, sizeof ether->ea);
ether->mbps = 100; // XXX what speed?
ether->attach = etherxenattach;
ether->detach = nil;
ether->transmit = etherxentransmit;
ether->irq = -1;
ether->tbdf = BUSUNKNOWN;
ether->ifstat = ifstat;
ether->ctl = etherxenctl;
ether->promiscuous = nil;
ether->multicast = etherxenmulticast;
ether->arg = ether;
intrenable(ether->irq, etherxenintr, ether, ether->tbdf, ether->name);
return 0;
}
void
etherxenlink(void)
{
addethercard("xen", pnp);
}
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