2.11BSD/sys/vaxif/if_uba.c
/*
* Copyright (c) 1982, 1986 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*
* @(#)if_uba.c 7.5.1.1 (Berkeley) 6/4/87
*/
#include "../machine/pte.h"
#include "param.h"
#include "systm.h"
#include "mbuf.h"
#include "map.h"
#include "buf.h"
#include "cmap.h"
#include "vmmac.h"
#include "socket.h"
#include "syslog.h"
#include "../net/if.h"
#include "../vax/mtpr.h"
#include "if_uba.h"
#include "../vaxuba/ubareg.h"
#include "../vaxuba/ubavar.h"
/*
* Routines supporting UNIBUS network interfaces.
*
* TODO:
* Support interfaces using only one BDP statically.
*/
/*
* Init UNIBUS for interface on uban whose headers of size hlen are to
* end on a page boundary. We allocate a UNIBUS map register for the page
* with the header, and nmr more UNIBUS map registers for i/o on the adapter,
* doing this once for each read and once for each write buffer. We also
* allocate page frames in the mbuffer pool for these pages.
*/
if_ubaminit(ifu, uban, hlen, nmr, ifr, nr, ifw, nw)
register struct ifubinfo *ifu;
int uban, hlen, nmr, nr, nw;
register struct ifrw *ifr;
register struct ifxmt *ifw;
{
register caddr_t p;
caddr_t cp;
int i, ncl, off;
if (hlen)
off = CLBYTES - hlen;
else
off = 0;
ncl = clrnd(nmr) / CLSIZE;
if (hlen)
ncl++;
if (ifr[0].ifrw_addr)
cp = ifr[0].ifrw_addr - off;
else {
cp = m_clalloc((nr + nw) * ncl, MPG_SPACE, M_DONTWAIT);
if (cp == 0)
return (0);
p = cp;
for (i = 0; i < nr; i++) {
ifr[i].ifrw_addr = p + off;
p += ncl * CLBYTES;
}
for (i = 0; i < nw; i++) {
ifw[i].ifw_base = p;
ifw[i].ifw_addr = p + off;
p += ncl * CLBYTES;
}
ifu->iff_hlen = hlen;
ifu->iff_uban = uban;
ifu->iff_uba = uba_hd[uban].uh_uba;
}
for (i = 0; i < nr; i++)
if (if_ubaalloc(ifu, &ifr[i], nmr) == 0) {
nr = i;
nw = 0;
goto bad;
}
for (i = 0; i < nw; i++)
if (if_ubaalloc(ifu, &ifw[i].ifrw, nmr) == 0) {
nw = i;
goto bad;
}
while (--nw >= 0) {
for (i = 0; i < nmr; i++)
ifw[nw].ifw_wmap[i] = ifw[nw].ifw_mr[i];
ifw[nw].ifw_xswapd = 0;
ifw[nw].ifw_flags = IFRW_W;
ifw[nw].ifw_nmr = nmr;
}
return (1);
bad:
while (--nw >= 0)
ubarelse(ifu->iff_uban, &ifw[nw].ifw_info);
while (--nr >= 0)
ubarelse(ifu->iff_uban, &ifr[nr].ifrw_info);
m_pgfree(cp, (nr + nw) * ncl);
ifr[0].ifrw_addr = 0;
return (0);
}
/*
* Setup an ifrw structure by allocating UNIBUS map registers,
* possibly a buffered data path, and initializing the fields of
* the ifrw structure to minimize run-time overhead.
*/
static
if_ubaalloc(ifu, ifrw, nmr)
struct ifubinfo *ifu;
register struct ifrw *ifrw;
int nmr;
{
register int info;
info =
uballoc(ifu->iff_uban, ifrw->ifrw_addr, nmr*NBPG + ifu->iff_hlen,
ifu->iff_flags);
if (info == 0)
return (0);
ifrw->ifrw_info = info;
ifrw->ifrw_bdp = UBAI_BDP(info);
ifrw->ifrw_proto = UBAMR_MRV | (UBAI_BDP(info) << UBAMR_DPSHIFT);
ifrw->ifrw_mr = &ifu->iff_uba->uba_map[UBAI_MR(info) + (ifu->iff_hlen?
1 : 0)];
return (1);
}
/*
* Pull read data off a interface.
* Len is length of data, with local net header stripped.
* Off is non-zero if a trailer protocol was used, and
* gives the offset of the trailer information.
* We copy the trailer information and then all the normal
* data into mbufs. When full cluster sized units are present
* on the interface on cluster boundaries we can get them more
* easily by remapping, and take advantage of this here.
* Prepend a pointer to the interface structure,
* so that protocols can determine where incoming packets arrived.
* Note: we may be called to receive from a transmit buffer by some
* devices. In that case, we must force normal mapping of the buffer,
* so that the correct data will appear (only unibus maps are
* changed when remapping the transmit buffers).
*/
struct mbuf *
if_ubaget(ifu, ifr, totlen, off0, ifp)
struct ifubinfo *ifu;
register struct ifrw *ifr;
int totlen, off0;
struct ifnet *ifp;
{
struct mbuf *top, **mp;
register struct mbuf *m;
int off = off0, len;
register caddr_t cp = ifr->ifrw_addr + ifu->iff_hlen, pp;
top = 0;
mp = ⊤
if (ifr->ifrw_flags & IFRW_W)
rcv_xmtbuf((struct ifxmt *)ifr);
while (totlen > 0) {
MGET(m, M_DONTWAIT, MT_DATA);
if (m == 0) {
m_freem(top);
top = 0;
goto out;
}
if (off) {
len = totlen - off;
cp = ifr->ifrw_addr + ifu->iff_hlen + off;
} else
len = totlen;
if (len >= CLBYTES/2) {
struct pte *cpte, *ppte;
int x, *ip, i;
/*
* If doing the first mbuf and
* the interface pointer hasn't been put in,
* put it in a separate mbuf to preserve alignment.
*/
if (ifp) {
len = 0;
goto nopage;
}
MCLGET(m);
if (m->m_len != CLBYTES)
goto nopage;
m->m_len = MIN(len, CLBYTES);
if (!claligned(cp))
goto copy;
/*
* Switch pages mapped to UNIBUS with new page pp,
* as quick form of copy. Remap UNIBUS and invalidate.
*/
pp = mtod(m, char *);
cpte = &Mbmap[mtocl(cp)*CLSIZE];
ppte = &Mbmap[mtocl(pp)*CLSIZE];
x = btop(cp - ifr->ifrw_addr);
ip = (int *)&ifr->ifrw_mr[x];
for (i = 0; i < CLSIZE; i++) {
struct pte t;
t = *ppte; *ppte++ = *cpte; *cpte = t;
*ip++ =
cpte++->pg_pfnum|ifr->ifrw_proto;
mtpr(TBIS, cp);
cp += NBPG;
mtpr(TBIS, (caddr_t)pp);
pp += NBPG;
}
goto nocopy;
}
nopage:
m->m_off = MMINOFF;
if (ifp) {
/*
* Leave room for ifp.
*/
m->m_len = MIN(MLEN - sizeof(ifp), len);
m->m_off += sizeof(ifp);
} else
m->m_len = MIN(MLEN, len);
copy:
bcopy(cp, mtod(m, caddr_t), (unsigned)m->m_len);
cp += m->m_len;
nocopy:
*mp = m;
mp = &m->m_next;
if (off) {
/* sort of an ALGOL-W style for statement... */
off += m->m_len;
if (off == totlen) {
cp = ifr->ifrw_addr + ifu->iff_hlen;
off = 0;
totlen = off0;
}
} else
totlen -= m->m_len;
if (ifp) {
/*
* Prepend interface pointer to first mbuf.
*/
m->m_len += sizeof(ifp);
m->m_off -= sizeof(ifp);
*(mtod(m, struct ifnet **)) = ifp;
ifp = (struct ifnet *)0;
}
}
out:
if (ifr->ifrw_flags & IFRW_W)
restor_xmtbuf((struct ifxmt *)ifr);
return (top);
}
/*
* Change the mapping on a transmit buffer so that if_ubaget may
* receive from that buffer. Copy data from any pages mapped to Unibus
* into the pages mapped to normal kernel virtual memory, so that
* they can be accessed and swapped as usual. We take advantage
* of the fact that clusters are placed on the xtofree list
* in inverse order, finding the last one.
*/
static
rcv_xmtbuf(ifw)
register struct ifxmt *ifw;
{
register struct mbuf *m;
struct mbuf **mprev;
register i;
char *cp;
while (i = ffs((long)ifw->ifw_xswapd)) {
cp = ifw->ifw_base + i * CLBYTES;
i--;
ifw->ifw_xswapd &= ~(1<<i);
mprev = &ifw->ifw_xtofree;
for (m = ifw->ifw_xtofree; m && m->m_next; m = m->m_next)
mprev = &m->m_next;
if (m == NULL)
break;
bcopy(mtod(m, caddr_t), cp, CLBYTES);
(void) m_free(m);
*mprev = NULL;
}
ifw->ifw_xswapd = 0;
for (i = 0; i < ifw->ifw_nmr; i++)
ifw->ifw_mr[i] = ifw->ifw_wmap[i];
}
/*
* Put a transmit buffer back together after doing an if_ubaget on it,
* which may have swapped pages.
*/
static
restor_xmtbuf(ifw)
register struct ifxmt *ifw;
{
register i;
for (i = 0; i < ifw->ifw_nmr; i++)
ifw->ifw_wmap[i] = ifw->ifw_mr[i];
}
/*
* Map a chain of mbufs onto a network interface
* in preparation for an i/o operation.
* The argument chain of mbufs includes the local network
* header which is copied to be in the mapped, aligned
* i/o space.
*/
if_ubaput(ifu, ifw, m)
struct ifubinfo *ifu;
register struct ifxmt *ifw;
register struct mbuf *m;
{
register struct mbuf *mp;
register caddr_t cp, dp;
register int i;
int xswapd = 0;
int x, cc, t;
cp = ifw->ifw_addr;
while (m) {
dp = mtod(m, char *);
if (claligned(cp) && claligned(dp) &&
(m->m_len == CLBYTES || m->m_next == (struct mbuf *)0)) {
struct pte *pte; int *ip;
pte = &Mbmap[mtocl(dp)*CLSIZE];
x = btop(cp - ifw->ifw_addr);
ip = (int *)&ifw->ifw_mr[x];
for (i = 0; i < CLSIZE; i++)
*ip++ =
ifw->ifw_proto | pte++->pg_pfnum;
xswapd |= 1 << (x>>(CLSHIFT-PGSHIFT));
mp = m->m_next;
m->m_next = ifw->ifw_xtofree;
ifw->ifw_xtofree = m;
cp += m->m_len;
} else {
bcopy(mtod(m, caddr_t), cp, (unsigned)m->m_len);
cp += m->m_len;
MFREE(m, mp);
}
m = mp;
}
/*
* Xswapd is the set of clusters we just mapped out. Ifu->iff_xswapd
* is the set of clusters mapped out from before. We compute
* the number of clusters involved in this operation in x.
* Clusters mapped out before and involved in this operation
* should be unmapped so original pages will be accessed by the device.
*/
cc = cp - ifw->ifw_addr;
x = ((cc - ifu->iff_hlen) + CLBYTES - 1) >> CLSHIFT;
ifw->ifw_xswapd &= ~xswapd;
while (i = ffs((long)ifw->ifw_xswapd)) {
i--;
if (i >= x)
break;
ifw->ifw_xswapd &= ~(1<<i);
i *= CLSIZE;
for (t = 0; t < CLSIZE; t++) {
ifw->ifw_mr[i] = ifw->ifw_wmap[i];
i++;
}
}
ifw->ifw_xswapd |= xswapd;
return (cc);
}