Revert "Staging: dgrp: Refactor the function dgrp_receive() in drrp_net_ops.c"

This reverts commit b73db54750482cf3910046c82a84ce8c1684dfbe.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: Chen Gang <gang.chen.5i5j@gmail.com>
Cc: Rashika Kheria <rashika.kheria@gmail.com>
Cc: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 155 insertions, 175 deletions

diff --git a/drivers/staging/dgrp/dgrp_net_ops.c b/drivers/staging/dgrp/dgrp_net_ops.c
index 1f61b89eca44..33ac7fb88cbd 100644
--- a/drivers/staging/dgrp/dgrp_net_ops.c
+++ b/drivers/staging/dgrp/dgrp_net_ops.c
@@ -2232,177 +2232,6 @@ done:
         return rtn;
 }
 
-/*
- * Common Packet Handling code
- */
-
-static void handle_data_in_packet(struct nd_struct *nd, struct ch_struct *ch,
-                                  long dlen, long plen, int n1, u8 *dbuf)
-{
-        char *error;
-        long n;
-        long remain;
-        u8 *buf;
-        u8 *b;
-
-        remain = nd->nd_remain;
-        nd->nd_tx_work = 1;
-
-        /*
-         *  Otherwise data should appear only when we are
-         *  in the CS_READY state.
-         */
-
-        if (ch->ch_state < CS_READY) {
-                error = "Data received before RWIN established";
-                nd->nd_remain = 0;
-                nd->nd_state = NS_SEND_ERROR;
-                nd->nd_error = error;
-        }
-
-        /*
-         *  Assure that the data received is within the
-         *  allowable window.
-         */
-
-        n = (ch->ch_s_rwin - ch->ch_s_rin) & 0xffff;
-
-        if (dlen > n) {
-                error = "Receive data overrun";
-                nd->nd_remain = 0;
-                nd->nd_state = NS_SEND_ERROR;
-                nd->nd_error = error;
-        }
-
-        /*
-         *  If we received 3 or less characters,
-         *  assume it is a human typing, and set RTIME
-         *  to 10 milliseconds.
-         *
-         *  If we receive 10 or more characters,
-         *  assume its not a human typing, and set RTIME
-         *  to 100 milliseconds.
-         */
-
-        if (ch->ch_edelay != DGRP_RTIME) {
-                if (ch->ch_rtime != ch->ch_edelay) {
-                        ch->ch_rtime = ch->ch_edelay;
-                        ch->ch_flag |= CH_PARAM;
-                }
-        } else if (dlen <= 3) {
-                if (ch->ch_rtime != 10) {
-                        ch->ch_rtime = 10;
-                        ch->ch_flag |= CH_PARAM;
-                }
-        } else {
-                if (ch->ch_rtime != DGRP_RTIME) {
-                        ch->ch_rtime = DGRP_RTIME;
-                        ch->ch_flag |= CH_PARAM;
-                }
-        }
-
-        /*
-         *  If a portion of the packet is outside the
-         *  buffer, shorten the effective length of the
-         *  data packet to be the amount of data received.
-         */
-
-        if (remain < plen)
-                dlen -= plen - remain;
-
-        /*
-         *  Detect if receive flush is now complete.
-         */
-
-        if ((ch->ch_flag & CH_RX_FLUSH) != 0 &&
-                        ((ch->ch_flush_seq - nd->nd_seq_out) & SEQ_MASK) >=
-                        ((nd->nd_seq_in    - nd->nd_seq_out) & SEQ_MASK)) {
-                ch->ch_flag &= ~CH_RX_FLUSH;
-        }
-
-        /*
-         *  If we are ready to receive, move the data into
-         *  the receive buffer.
-         */
-
-        ch->ch_s_rin = (ch->ch_s_rin + dlen) & 0xffff;
-
-        if (ch->ch_state == CS_READY &&
-                        (ch->ch_tun.un_open_count != 0) &&
-                        (ch->ch_tun.un_flag & UN_CLOSING) == 0 &&
-                        (ch->ch_cflag & CF_CREAD) != 0 &&
-                        (ch->ch_flag & (CH_BAUD0 | CH_RX_FLUSH)) == 0 &&
-                        (ch->ch_send & RR_RX_FLUSH) == 0) {
-
-                if (ch->ch_rin + dlen >= RBUF_MAX) {
-                        n = RBUF_MAX - ch->ch_rin;
-
-                        memcpy(ch->ch_rbuf + ch->ch_rin, dbuf, n);
-
-                        ch->ch_rin = 0;
-                        dbuf += n;
-                        dlen -= n;
-                }
-
-                memcpy(ch->ch_rbuf + ch->ch_rin, dbuf, dlen);
-
-                ch->ch_rin += dlen;
-
-
-                /*
-                 *  If we are not in fastcook mode, or
-                 *  if there is a fastcook thread
-                 *  waiting for data, send the data to
-                 *  the line discipline.
-                 */
-
-                if ((ch->ch_flag & CH_FAST_READ) == 0 ||
-                                ch->ch_inwait != 0) {
-                        dgrp_input(ch);
-                }
-
-                /*
-                 *  If there is a read thread waiting
-                 *  in select, and we are in fastcook
-                 *  mode, wake him up.
-                 */
-
-                if (waitqueue_active(&ch->ch_tun.un_tty->read_wait) &&
-                                (ch->ch_flag & CH_FAST_READ) != 0)
-                        wake_up_interruptible(&ch->ch_tun.un_tty->read_wait);
-
-                /*
-                 * Wake any thread waiting in the
-                 * fastcook loop.
-                 */
-
-                if ((ch->ch_flag & CH_INPUT) != 0) {
-                        ch->ch_flag &= ~CH_INPUT;
-                        wake_up_interruptible(&ch->ch_flag_wait);
-                }
-        }
-
-        /*
-         *  Fabricate and insert a data packet header to
-         *  preced the remaining data when it comes in.
-         */
-
-        if (remain < plen) {
-                dlen = plen - remain;
-                b = buf;
-
-                b[0] = 0x90 + n1;
-                put_unaligned_be16(dlen, b + 1);
-
-                remain = 3;
-                if (remain > 0 && b != buf)
-                        memcpy(buf, b, remain);
-
-                nd->nd_remain = remain;
-                return;
-        }
-}
-
 /**
  * dgrp_receive() -- decode data packets received from the remote PortServer.
  * @nd: pointer to a node structure
@@ -2477,8 +2306,7 @@ static void dgrp_receive(struct nd_struct *nd)
                         plen = dlen + 1;
 
                         dbuf = b + 1;
-                        handle_data_in_packet(nd, ch, dlen, plen, n1, dbuf);
-                        break;
+                        goto data;
 
                 /*
                  *  Process 2-byte header data packet.
@@ -2492,8 +2320,7 @@ static void dgrp_receive(struct nd_struct *nd)
                         plen = dlen + 2;
 
                         dbuf = b + 2;
-                        handle_data_in_packet(nd, ch, dlen, plen, n1, dbuf);
-                        break;
+                        goto data;
 
                 /*
                  *  Process 3-byte header data packet.
@@ -2508,6 +2335,159 @@ static void dgrp_receive(struct nd_struct *nd)
 
                         dbuf = b + 3;
 
+                /*
+                 *  Common packet handling code.
+                 */
+
+data:
+                        nd->nd_tx_work = 1;
+
+                        /*
+                         *  Otherwise data should appear only when we are
+                         *  in the CS_READY state.
+                         */
+
+                        if (ch->ch_state < CS_READY) {
+                                error = "Data received before RWIN established";
+                                goto prot_error;
+                        }
+
+                        /*
+                         *  Assure that the data received is within the
+                         *  allowable window.
+                         */
+
+                        n = (ch->ch_s_rwin - ch->ch_s_rin) & 0xffff;
+
+                        if (dlen > n) {
+                                error = "Receive data overrun";
+                                goto prot_error;
+                        }
+
+                        /*
+                         *  If we received 3 or less characters,
+                         *  assume it is a human typing, and set RTIME
+                         *  to 10 milliseconds.
+                         *
+                         *  If we receive 10 or more characters,
+                         *  assume its not a human typing, and set RTIME
+                         *  to 100 milliseconds.
+                         */
+
+                        if (ch->ch_edelay != DGRP_RTIME) {
+                                if (ch->ch_rtime != ch->ch_edelay) {
+                                        ch->ch_rtime = ch->ch_edelay;
+                                        ch->ch_flag |= CH_PARAM;
+                                }
+                        } else if (dlen <= 3) {
+                                if (ch->ch_rtime != 10) {
+                                        ch->ch_rtime = 10;
+                                        ch->ch_flag |= CH_PARAM;
+                                }
+                        } else {
+                                if (ch->ch_rtime != DGRP_RTIME) {
+                                        ch->ch_rtime = DGRP_RTIME;
+                                        ch->ch_flag |= CH_PARAM;
+                                }
+                        }
+
+                        /*
+                         *  If a portion of the packet is outside the
+                         *  buffer, shorten the effective length of the
+                         *  data packet to be the amount of data received.
+                         */
+
+                        if (remain < plen)
+                                dlen -= plen - remain;
+
+                        /*
+                         *  Detect if receive flush is now complete.
+                         */
+
+                        if ((ch->ch_flag & CH_RX_FLUSH) != 0 &&
+                            ((ch->ch_flush_seq - nd->nd_seq_out) & SEQ_MASK) >=
+                            ((nd->nd_seq_in    - nd->nd_seq_out) & SEQ_MASK)) {
+                                ch->ch_flag &= ~CH_RX_FLUSH;
+                        }
+
+                        /*
+                         *  If we are ready to receive, move the data into
+                         *  the receive buffer.
+                         */
+
+                        ch->ch_s_rin = (ch->ch_s_rin + dlen) & 0xffff;
+
+                        if (ch->ch_state == CS_READY &&
+                            (ch->ch_tun.un_open_count != 0) &&
+                            (ch->ch_tun.un_flag & UN_CLOSING) == 0 &&
+                            (ch->ch_cflag & CF_CREAD) != 0 &&
+                            (ch->ch_flag & (CH_BAUD0 | CH_RX_FLUSH)) == 0 &&
+                            (ch->ch_send & RR_RX_FLUSH) == 0) {
+
+                                if (ch->ch_rin + dlen >= RBUF_MAX) {
+                                        n = RBUF_MAX - ch->ch_rin;
+
+                                        memcpy(ch->ch_rbuf + ch->ch_rin, dbuf, n);
+
+                                        ch->ch_rin = 0;
+                                        dbuf += n;
+                                        dlen -= n;
+                                }
+
+                                memcpy(ch->ch_rbuf + ch->ch_rin, dbuf, dlen);
+
+                                ch->ch_rin += dlen;
+
+
+                                /*
+                                 *  If we are not in fastcook mode, or
+                                 *  if there is a fastcook thread
+                                 *  waiting for data, send the data to
+                                 *  the line discipline.
+                                 */
+
+                                if ((ch->ch_flag & CH_FAST_READ) == 0 ||
+                                    ch->ch_inwait != 0) {
+                                        dgrp_input(ch);
+                                }
+
+                                /*
+                                 *  If there is a read thread waiting
+                                 *  in select, and we are in fastcook
+                                 *  mode, wake him up.
+                                 */
+
+                                if (waitqueue_active(&ch->ch_tun.un_tty->read_wait) &&
+                                    (ch->ch_flag & CH_FAST_READ) != 0)
+                                        wake_up_interruptible(&ch->ch_tun.un_tty->read_wait);
+
+                                /*
+                                 * Wake any thread waiting in the
+                                 * fastcook loop.
+                                 */
+
+                                if ((ch->ch_flag & CH_INPUT) != 0) {
+                                        ch->ch_flag &= ~CH_INPUT;
+
+                                        wake_up_interruptible(&ch->ch_flag_wait);
+                                }
+                        }
+
+                        /*
+                         *  Fabricate and insert a data packet header to
+                         *  preced the remaining data when it comes in.
+                         */
+
+                        if (remain < plen) {
+                                dlen = plen - remain;
+                                b = buf;
+
+                                b[0] = 0x90 + n1;
+                                put_unaligned_be16(dlen, b + 1);
+
+                                remain = 3;
+                                goto done;
+                        }
                         break;
 
                 /*