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[SPARC64]: Assorted LDC bug cures.
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1) LDC_MODE_RELIABLE is deprecated an unused by anything, plus
   it and LDC_MODE_STREAM were mis-numbered.

2) read_stream() should try to read as much as possible into
   the per-LDC stream buffer area, so do not trim the read_nonraw()
   length by the caller's size parameter.

3) Send data ACKs when necessary in read_nonraw().

4) In read_nonraw() when we get a pure ACK, advance the RX head
   unconditionally past it.

5) Provide the ACKID field in the ldcdgb() packet dump in read_nonraw().
   This helps debugging stream mode LDC channel problems.

6) Decrease verbosity of rx_data_wait() so that it is more useful.
   A debugging message each loop iteration is too much.

7) In process_data_ack() stop the loop checking when we hit lp->tx_tail
   not lp->tx_head.

8) Set the seqid field properly in send_data_nack().

Signed-off-by: David S. Miller <davem@davemloft.net>
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David S. Miller committed Jul 16, 2007
1 parent 5a606b7 commit cb48123
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Showing 2 changed files with 39 additions and 20 deletions.
56 changes: 38 additions & 18 deletions arch/sparc64/kernel/ldc.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -239,8 +239,7 @@ static struct ldc_packet *handshake_get_tx_packet(struct ldc_channel *lp,
*/
static unsigned long head_for_data(struct ldc_channel *lp)
{
if (lp->cfg.mode == LDC_MODE_RELIABLE ||
lp->cfg.mode == LDC_MODE_STREAM)
if (lp->cfg.mode == LDC_MODE_STREAM)
return lp->tx_acked;
return lp->tx_head;
}
Expand Down Expand Up @@ -494,7 +493,7 @@ static int send_data_nack(struct ldc_channel *lp, struct ldc_packet *data_pkt)
p->type = data_pkt->type;
p->stype = LDC_NACK;
p->ctrl = data_pkt->ctrl & LDC_CTRL_MSK;
p->seqid = lp->snd_nxt;
p->seqid = lp->snd_nxt + 1;
p->u.r.ackid = lp->rcv_nxt;

ldcdbg(HS, "SEND DATA NACK type[0x%x] ctl[0x%x] seq[0x%x] ack[0x%x]\n",
Expand Down Expand Up @@ -765,7 +764,7 @@ static int process_data_ack(struct ldc_channel *lp,
lp->tx_acked = head;
return 0;
}
if (head == lp->tx_head)
if (head == lp->tx_tail)
return ldc_abort(lp);
}

Expand Down Expand Up @@ -1093,11 +1092,6 @@ struct ldc_channel *ldc_alloc(unsigned long id,
mss = LDC_PACKET_SIZE - 8;
break;

case LDC_MODE_RELIABLE:
mops = &nonraw_ops;
mss = LDC_PACKET_SIZE - 8 - 8;
break;

case LDC_MODE_STREAM:
mops = &stream_ops;
mss = LDC_PACKET_SIZE - 8 - 8;
Expand Down Expand Up @@ -1579,15 +1573,14 @@ static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head)
if (hv_err)
return ldc_abort(lp);

ldcdbg(DATA, "REREAD head[%lx] tail[%lx] chan_state[%lx]\n",
dummy, lp->rx_tail, lp->chan_state);

if (lp->chan_state == LDC_CHANNEL_DOWN ||
lp->chan_state == LDC_CHANNEL_RESETTING)
return -ECONNRESET;

if (cur_head != lp->rx_tail) {
ldcdbg(DATA, "DATA WAIT DONE\n");
ldcdbg(DATA, "DATA WAIT DONE "
"head[%lx] tail[%lx] chan_state[%lx]\n",
dummy, lp->rx_tail, lp->chan_state);
return 0;
}

Expand All @@ -1607,6 +1600,28 @@ static int rx_set_head(struct ldc_channel *lp, unsigned long head)
return 0;
}

static void send_data_ack(struct ldc_channel *lp)
{
unsigned long new_tail;
struct ldc_packet *p;

p = data_get_tx_packet(lp, &new_tail);
if (likely(p)) {
int err;

memset(p, 0, sizeof(*p));
p->type = LDC_DATA;
p->stype = LDC_ACK;
p->ctrl = 0;
p->seqid = lp->snd_nxt + 1;
p->u.r.ackid = lp->rcv_nxt;

err = send_tx_packet(lp, p, new_tail);
if (!err)
lp->snd_nxt++;
}
}

static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
{
struct ldc_packet *first_frag;
Expand Down Expand Up @@ -1637,13 +1652,14 @@ static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
BUG_ON(new == lp->rx_tail);
p = lp->rx_base + (new / LDC_PACKET_SIZE);

ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x] "
ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x:%08x] "
"rcv_nxt[%08x]\n",
p->type,
p->stype,
p->ctrl,
p->env,
p->seqid,
p->u.r.ackid,
lp->rcv_nxt);

if (unlikely(!rx_seq_ok(lp, p->seqid))) {
Expand Down Expand Up @@ -1672,6 +1688,9 @@ static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
}
if (!(p->stype & LDC_INFO)) {
new = rx_advance(lp, new);
err = rx_set_head(lp, new);
if (err)
break;
goto no_data;
}

Expand Down Expand Up @@ -1748,8 +1767,11 @@ static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
if (err && first_frag)
lp->rcv_nxt = first_frag->seqid - 1;

if (!err)
if (!err) {
err = copied;
if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE)
send_data_ack(lp);
}

return err;
}
Expand All @@ -1770,9 +1792,7 @@ static int write_stream(struct ldc_channel *lp, const void *buf,
static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size)
{
if (!lp->mssbuf_len) {
int err = read_nonraw(lp, lp->mssbuf,
(size > lp->cfg.mtu ?
lp->cfg.mtu : size));
int err = read_nonraw(lp, lp->mssbuf, lp->cfg.mtu);
if (err < 0)
return err;

Expand Down
3 changes: 1 addition & 2 deletions include/asm-sparc64/ldc.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -25,8 +25,7 @@ struct ldc_channel_config {
#define LDC_MODE_RAW 0x00
#define LDC_MODE_UNRELIABLE 0x01
#define LDC_MODE_RESERVED 0x02
#define LDC_MODE_RELIABLE 0x03
#define LDC_MODE_STREAM 0x04
#define LDC_MODE_STREAM 0x03

u8 debug;
#define LDC_DEBUG_HS 0x01
Expand Down

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