/* rxi_ReadProc -- internal version.
*
* LOCKS USED -- called at netpri
*/
int
rxi_ReadProc(struct rx_call *call, char *buf,
int nbytes)
{
struct rx_packet *cp = call->currentPacket;
struct rx_packet *rp;
int requestCount;
unsigned int t;
/* XXXX took out clock_NewTime from here. Was it needed? */
requestCount = nbytes;
/* Free any packets from the last call to ReadvProc/WritevProc */
if (queue_IsNotEmpty(&call->iovq)) {
#ifdef RXDEBUG_PACKET
call->iovqc -=
#endif /* RXDEBUG_PACKET */
rxi_FreePackets(0, &call->iovq);
}
do {
if (call->nLeft == 0) {
/* Get next packet */
MUTEX_ENTER(&call->lock);
for (;;) {
if (call->error || (call->mode != RX_MODE_RECEIVING)) {
if (call->error) {
call->mode = RX_MODE_ERROR;
MUTEX_EXIT(&call->lock);
return 0;
}
if (call->mode == RX_MODE_SENDING) {
MUTEX_EXIT(&call->lock);
rxi_FlushWrite(call);
MUTEX_ENTER(&call->lock);
continue;
}
}
if (queue_IsNotEmpty(&call->rq)) {
/* Check that next packet available is next in sequence */
rp = queue_First(&call->rq, rx_packet);
if (rp->header.seq == call->rnext) {
afs_int32 error;
struct rx_connection *conn = call->conn;
queue_Remove(rp);
#ifdef RX_TRACK_PACKETS
rp->flags &= ~RX_PKTFLAG_RQ;
#endif
#ifdef RXDEBUG_PACKET
call->rqc--;
#endif /* RXDEBUG_PACKET */
/* RXS_CheckPacket called to undo RXS_PreparePacket's
* work. It may reduce the length of the packet by up
* to conn->maxTrailerSize, to reflect the length of the
* data + the header. */
if ((error =
RXS_CheckPacket(conn->securityObject, call,
rp))) {
/* Used to merely shut down the call, but now we
* shut down the whole connection since this may
* indicate an attempt to hijack it */
MUTEX_EXIT(&call->lock);
rxi_ConnectionError(conn, error);
MUTEX_ENTER(&conn->conn_data_lock);
rp = rxi_SendConnectionAbort(conn, rp, 0, 0);
MUTEX_EXIT(&conn->conn_data_lock);
rxi_FreePacket(rp);
return 0;
}
call->rnext++;
cp = call->currentPacket = rp;
#ifdef RX_TRACK_PACKETS
call->currentPacket->flags |= RX_PKTFLAG_CP;
#endif
call->curvec = 1; /* 0th vec is always header */
/* begin at the beginning [ more or less ], continue
* on until the end, then stop. */
call->curpos =
(char *)cp->wirevec[1].iov_base +
call->conn->securityHeaderSize;
call->curlen =
cp->wirevec[1].iov_len -
call->conn->securityHeaderSize;
/* Notice that this code works correctly if the data
* size is 0 (which it may be--no reply arguments from
* server, for example). This relies heavily on the
* fact that the code below immediately frees the packet
* (no yields, etc.). If it didn't, this would be a
* problem because a value of zero for call->nLeft
* normally means that there is no read packet */
call->nLeft = cp->length;
hadd32(call->bytesRcvd, cp->length);
/* Send a hard ack for every rxi_HardAckRate+1 packets
* consumed. Otherwise schedule an event to send
* the hard ack later on.
*/
call->nHardAcks++;
if (!(call->flags & RX_CALL_RECEIVE_DONE)) {
if (call->nHardAcks > (u_short) rxi_HardAckRate) {
rxevent_Cancel(call->delayedAckEvent, call,
RX_CALL_REFCOUNT_DELAY);
rxi_SendAck(call, 0, 0, RX_ACK_DELAY, 0);
} else {
struct clock when, now;
clock_GetTime(&now);
when = now;
/* Delay to consolidate ack packets */
clock_Add(&when, &rx_hardAckDelay);
if (!call->delayedAckEvent
|| clock_Gt(&call->delayedAckEvent->
eventTime, &when)) {
rxevent_Cancel(call->delayedAckEvent,
call,
RX_CALL_REFCOUNT_DELAY);
MUTEX_ENTER(&rx_refcnt_mutex);
CALL_HOLD(call, RX_CALL_REFCOUNT_DELAY);
MUTEX_EXIT(&rx_refcnt_mutex);
call->delayedAckEvent =
rxevent_PostNow(&when, &now,
rxi_SendDelayedAck, call,
0);
}
}
}
break;
}
}
/*
* If we reach this point either we have no packets in the
* receive queue or the next packet in the queue is not the
* one we are looking for. There is nothing else for us to
* do but wait for another packet to arrive.
*/
/* Are there ever going to be any more packets? */
if (call->flags & RX_CALL_RECEIVE_DONE) {
MUTEX_EXIT(&call->lock);
return requestCount - nbytes;
}
/* Wait for in-sequence packet */
call->flags |= RX_CALL_READER_WAIT;
clock_NewTime();
call->startWait = clock_Sec();
while (call->flags & RX_CALL_READER_WAIT) {
#ifdef RX_ENABLE_LOCKS
CV_WAIT(&call->cv_rq, &call->lock);
#else
osi_rxSleep(&call->rq);
#endif
}
cp = call->currentPacket;
call->startWait = 0;
#ifdef RX_ENABLE_LOCKS
if (call->error) {
MUTEX_EXIT(&call->lock);
return 0;
}
#endif /* RX_ENABLE_LOCKS */
}
MUTEX_EXIT(&call->lock);
} else
/* osi_Assert(cp); */
/* MTUXXX this should be replaced by some error-recovery code before shipping */
/* yes, the following block is allowed to be the ELSE clause (or not) */
/* It's possible for call->nLeft to be smaller than any particular
* iov_len. Usually, recvmsg doesn't change the iov_len, since it
* reflects the size of the buffer. We have to keep track of the
* number of bytes read in the length field of the packet struct. On
* the final portion of a received packet, it's almost certain that
* call->nLeft will be smaller than the final buffer. */
while (nbytes && cp) {
t = MIN((int)call->curlen, nbytes);
t = MIN(t, (int)call->nLeft);
memcpy(buf, call->curpos, t);
buf += t;
nbytes -= t;
call->curpos += t;
call->curlen -= t;
call->nLeft -= t;
if (!call->nLeft) {
/* out of packet. Get another one. */
#ifdef RX_TRACK_PACKETS
call->currentPacket->flags &= ~RX_PKTFLAG_CP;
#endif
rxi_FreePacket(cp);
cp = call->currentPacket = (struct rx_packet *)0;
} else if (!call->curlen) {
/* need to get another struct iov */
if (++call->curvec >= cp->niovecs) {
/* current packet is exhausted, get ready for another */
/* don't worry about curvec and stuff, they get set somewhere else */
#ifdef RX_TRACK_PACKETS
call->currentPacket->flags &= ~RX_PKTFLAG_CP;
#endif
rxi_FreePacket(cp);
cp = call->currentPacket = (struct rx_packet *)0;
call->nLeft = 0;
} else {
call->curpos =
(char *)cp->wirevec[call->curvec].iov_base;
call->curlen = cp->wirevec[call->curvec].iov_len;
}
}
}
if (!nbytes) {
/* user buffer is full, return */
return requestCount;
}
} while (nbytes);
return requestCount;
}
static int
rxi_GetNextPacket(struct rx_call *call) {
struct rx_packet *rp;
int error;
if (call->app.currentPacket != NULL) {
#ifdef RX_TRACK_PACKETS
call->app.currentPacket->flags |= RX_PKTFLAG_CP;
#endif
rxi_FreePacket(call->app.currentPacket);
call->app.currentPacket = NULL;
}
if (opr_queue_IsEmpty(&call->rq))
return 0;
/* Check that next packet available is next in sequence */
rp = opr_queue_First(&call->rq, struct rx_packet, entry);
if (rp->header.seq != call->rnext)
return 0;
opr_queue_Remove(&rp->entry);
#ifdef RX_TRACK_PACKETS
rp->flags &= ~RX_PKTFLAG_RQ;
#endif
#ifdef RXDEBUG_PACKET
call->rqc--;
#endif /* RXDEBUG_PACKET */
/* RXS_CheckPacket called to undo RXS_PreparePacket's work. It may
* reduce the length of the packet by up to conn->maxTrailerSize,
* to reflect the length of the data + the header. */
if ((error = RXS_CheckPacket(call->conn->securityObject, call, rp))) {
/* Used to merely shut down the call, but now we shut down the whole
* connection since this may indicate an attempt to hijack it */
MUTEX_EXIT(&call->lock);
rxi_ConnectionError(call->conn, error);
MUTEX_ENTER(&call->conn->conn_data_lock);
rp = rxi_SendConnectionAbort(call->conn, rp, 0, 0);
MUTEX_EXIT(&call->conn->conn_data_lock);
rxi_FreePacket(rp);
return error;
}
call->rnext++;
call->app.currentPacket = rp;
#ifdef RX_TRACK_PACKETS
call->app.currentPacket->flags |= RX_PKTFLAG_CP;
#endif
call->app.curvec = 1; /* 0th vec is always header */
/* begin at the beginning [ more or less ], continue on until the end,
* then stop. */
call->app.curpos = (char *)call->app.currentPacket->wirevec[1].iov_base +
call->conn->securityHeaderSize;
call->app.curlen = call->app.currentPacket->wirevec[1].iov_len -
call->conn->securityHeaderSize;
call->app.nLeft = call->app.currentPacket->length;
call->app.bytesRcvd += call->app.currentPacket->length;
call->nHardAcks++;
return 0;
}
/* rxi_FillReadVec
*
* Uses packets in the receive queue to fill in as much of the
* current iovec as possible. Does not block if it runs out
* of packets to complete the iovec. Return true if an ack packet
* was sent, otherwise return false */
int
rxi_FillReadVec(struct rx_call *call, afs_uint32 serial)
{
int didConsume = 0;
int didHardAck = 0;
unsigned int t;
struct rx_packet *rp;
struct rx_packet *curp;
struct iovec *call_iov;
struct iovec *cur_iov = NULL;
curp = call->currentPacket;
if (curp) {
cur_iov = &curp->wirevec[call->curvec];
}
call_iov = &call->iov[call->iovNext];
while (!call->error && call->iovNBytes && call->iovNext < call->iovMax) {
if (call->nLeft == 0) {
/* Get next packet */
if (queue_IsNotEmpty(&call->rq)) {
/* Check that next packet available is next in sequence */
rp = queue_First(&call->rq, rx_packet);
if (rp->header.seq == call->rnext) {
afs_int32 error;
struct rx_connection *conn = call->conn;
queue_Remove(rp);
#ifdef RX_TRACK_PACKETS
rp->flags &= ~RX_PKTFLAG_RQ;
#endif
#ifdef RXDEBUG_PACKET
call->rqc--;
#endif /* RXDEBUG_PACKET */
/* RXS_CheckPacket called to undo RXS_PreparePacket's
* work. It may reduce the length of the packet by up
* to conn->maxTrailerSize, to reflect the length of the
* data + the header. */
if ((error =
RXS_CheckPacket(conn->securityObject, call, rp))) {
/* Used to merely shut down the call, but now we
* shut down the whole connection since this may
* indicate an attempt to hijack it */
MUTEX_EXIT(&call->lock);
rxi_ConnectionError(conn, error);
MUTEX_ENTER(&conn->conn_data_lock);
rp = rxi_SendConnectionAbort(conn, rp, 0, 0);
MUTEX_EXIT(&conn->conn_data_lock);
rxi_FreePacket(rp);
MUTEX_ENTER(&call->lock);
return 1;
}
call->rnext++;
curp = call->currentPacket = rp;
#ifdef RX_TRACK_PACKETS
call->currentPacket->flags |= RX_PKTFLAG_CP;
#endif
call->curvec = 1; /* 0th vec is always header */
cur_iov = &curp->wirevec[1];
/* begin at the beginning [ more or less ], continue
* on until the end, then stop. */
call->curpos =
(char *)curp->wirevec[1].iov_base +
call->conn->securityHeaderSize;
call->curlen =
curp->wirevec[1].iov_len -
call->conn->securityHeaderSize;
/* Notice that this code works correctly if the data
* size is 0 (which it may be--no reply arguments from
* server, for example). This relies heavily on the
* fact that the code below immediately frees the packet
* (no yields, etc.). If it didn't, this would be a
* problem because a value of zero for call->nLeft
* normally means that there is no read packet */
call->nLeft = curp->length;
hadd32(call->bytesRcvd, curp->length);
/* Send a hard ack for every rxi_HardAckRate+1 packets
* consumed. Otherwise schedule an event to send
* the hard ack later on.
*/
call->nHardAcks++;
didConsume = 1;
continue;
}
}
break;
}
/* It's possible for call->nLeft to be smaller than any particular
* iov_len. Usually, recvmsg doesn't change the iov_len, since it
* reflects the size of the buffer. We have to keep track of the
* number of bytes read in the length field of the packet struct. On
* the final portion of a received packet, it's almost certain that
* call->nLeft will be smaller than the final buffer. */
while (call->iovNBytes && call->iovNext < call->iovMax && curp) {
t = MIN((int)call->curlen, call->iovNBytes);
t = MIN(t, (int)call->nLeft);
call_iov->iov_base = call->curpos;
call_iov->iov_len = t;
call_iov++;
call->iovNext++;
call->iovNBytes -= t;
call->curpos += t;
call->curlen -= t;
call->nLeft -= t;
if (!call->nLeft) {
/* out of packet. Get another one. */
#ifdef RX_TRACK_PACKETS
curp->flags &= ~RX_PKTFLAG_CP;
curp->flags |= RX_PKTFLAG_IOVQ;
#endif
queue_Append(&call->iovq, curp);
#ifdef RXDEBUG_PACKET
call->iovqc++;
#endif /* RXDEBUG_PACKET */
curp = call->currentPacket = (struct rx_packet *)0;
} else if (!call->curlen) {
/* need to get another struct iov */
if (++call->curvec >= curp->niovecs) {
/* current packet is exhausted, get ready for another */
/* don't worry about curvec and stuff, they get set somewhere else */
#ifdef RX_TRACK_PACKETS
curp->flags &= ~RX_PKTFLAG_CP;
curp->flags |= RX_PKTFLAG_IOVQ;
#endif
queue_Append(&call->iovq, curp);
#ifdef RXDEBUG_PACKET
call->iovqc++;
#endif /* RXDEBUG_PACKET */
curp = call->currentPacket = (struct rx_packet *)0;
call->nLeft = 0;
} else {
cur_iov++;
call->curpos = (char *)cur_iov->iov_base;
call->curlen = cur_iov->iov_len;
}
}
}
}
/* If we consumed any packets then check whether we need to
* send a hard ack. */
if (didConsume && (!(call->flags & RX_CALL_RECEIVE_DONE))) {
if (call->nHardAcks > (u_short) rxi_HardAckRate) {
rxevent_Cancel(call->delayedAckEvent, call,
RX_CALL_REFCOUNT_DELAY);
rxi_SendAck(call, 0, serial, RX_ACK_DELAY, 0);
didHardAck = 1;
} else {
struct clock when, now;
clock_GetTime(&now);
when = now;
/* Delay to consolidate ack packets */
clock_Add(&when, &rx_hardAckDelay);
if (!call->delayedAckEvent
|| clock_Gt(&call->delayedAckEvent->eventTime, &when)) {
rxevent_Cancel(call->delayedAckEvent, call,
RX_CALL_REFCOUNT_DELAY);
MUTEX_ENTER(&rx_refcnt_mutex);
CALL_HOLD(call, RX_CALL_REFCOUNT_DELAY);
MUTEX_EXIT(&rx_refcnt_mutex);
call->delayedAckEvent =
rxevent_PostNow(&when, &now, rxi_SendDelayedAck, call, 0);
}
}
}
return didHardAck;
}
