Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 309 insertions, 0 deletions

diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
new file mode 100644
index 000000000000..0c2ab7885058
--- /dev/null
+++ b/net/sctp/chunk.c
@@ -0,0 +1,309 @@
+/* SCTP kernel reference Implementation
+ * (C) Copyright IBM Corp. 2003, 2004
+ *
+ * This file is part of the SCTP kernel reference Implementation
+ *
+ * This file contains the code relating the the chunk abstraction.
+ *
+ * The SCTP reference implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * The SCTP reference implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <lksctp-developers@lists.sourceforge.net>
+ *
+ * Or submit a bug report through the following website:
+ *    http://www.sf.net/projects/lksctp
+ *
+ * Written or modified by:
+ *    Jon Grimm             <jgrimm@us.ibm.com>
+ *    Sridhar Samudrala     <sri@us.ibm.com>
+ *
+ * Any bugs reported given to us we will try to fix... any fixes shared will
+ * be incorporated into the next SCTP release.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/net.h>
+#include <linux/inet.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+
+/* This file is mostly in anticipation of future work, but initially
+ * populate with fragment tracking for an outbound message.
+ */
+
+/* Initialize datamsg from memory. */
+static void sctp_datamsg_init(struct sctp_datamsg *msg)
+{
+        atomic_set(&msg->refcnt, 1);
+        msg->send_failed = 0;
+        msg->send_error = 0;
+        msg->can_abandon = 0;
+        msg->expires_at = 0;
+        INIT_LIST_HEAD(&msg->chunks);
+}
+
+/* Allocate and initialize datamsg. */
+SCTP_STATIC struct sctp_datamsg *sctp_datamsg_new(int gfp)
+{
+        struct sctp_datamsg *msg;
+        msg = kmalloc(sizeof(struct sctp_datamsg), gfp);
+        if (msg)
+                sctp_datamsg_init(msg);
+        SCTP_DBG_OBJCNT_INC(datamsg);
+        return msg;
+}
+
+/* Final destructruction of datamsg memory. */
+static void sctp_datamsg_destroy(struct sctp_datamsg *msg)
+{
+        struct list_head *pos, *temp;
+        struct sctp_chunk *chunk;
+        struct sctp_sock *sp;
+        struct sctp_ulpevent *ev;
+        struct sctp_association *asoc = NULL;
+        int error = 0, notify;
+
+        /* If we failed, we may need to notify. */
+        notify = msg->send_failed ? -1 : 0;
+
+        /* Release all references. */
+        list_for_each_safe(pos, temp, &msg->chunks) {
+                list_del_init(pos);
+                chunk = list_entry(pos, struct sctp_chunk, frag_list);
+                /* Check whether we _really_ need to notify. */
+                if (notify < 0) {
+                        asoc = chunk->asoc;
+                        if (msg->send_error)
+                                error = msg->send_error;
+                        else
+                                error = asoc->outqueue.error;
+
+                        sp = sctp_sk(asoc->base.sk);
+                        notify = sctp_ulpevent_type_enabled(SCTP_SEND_FAILED,
+                                                            &sp->subscribe);
+                }
+
+                /* Generate a SEND FAILED event only if enabled. */
+                if (notify > 0) {
+                        int sent;
+                        if (chunk->has_tsn)
+                                sent = SCTP_DATA_SENT;
+                        else
+                                sent = SCTP_DATA_UNSENT;
+
+                        ev = sctp_ulpevent_make_send_failed(asoc, chunk, sent,
+                                                            error, GFP_ATOMIC);
+                        if (ev)
+                                sctp_ulpq_tail_event(&asoc->ulpq, ev);
+                }
+
+                sctp_chunk_put(chunk);
+        }
+
+        SCTP_DBG_OBJCNT_DEC(datamsg);
+        kfree(msg);
+}
+
+/* Hold a reference. */
+static void sctp_datamsg_hold(struct sctp_datamsg *msg)
+{
+        atomic_inc(&msg->refcnt);
+}
+
+/* Release a reference. */
+void sctp_datamsg_put(struct sctp_datamsg *msg)
+{
+        if (atomic_dec_and_test(&msg->refcnt))
+                sctp_datamsg_destroy(msg);
+}
+
+/* Free a message.  Really just give up a reference, the
+ * really free happens in sctp_datamsg_destroy().
+ */
+void sctp_datamsg_free(struct sctp_datamsg *msg)
+{
+        sctp_datamsg_put(msg);
+}
+
+/* Hold on to all the fragments until all chunks have been sent. */
+void sctp_datamsg_track(struct sctp_chunk *chunk)
+{
+        sctp_chunk_hold(chunk);
+}
+
+/* Assign a chunk to this datamsg. */
+static void sctp_datamsg_assign(struct sctp_datamsg *msg, struct sctp_chunk *chunk)
+{
+        sctp_datamsg_hold(msg);
+        chunk->msg = msg;
+}
+
+
+/* A data chunk can have a maximum payload of (2^16 - 20).  Break
+ * down any such message into smaller chunks.  Opportunistically, fragment
+ * the chunks down to the current MTU constraints.  We may get refragmented
+ * later if the PMTU changes, but it is _much better_ to fragment immediately
+ * with a reasonable guess than always doing our fragmentation on the
+ * soft-interrupt.
+ */
+struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
+                                            struct sctp_sndrcvinfo *sinfo,
+                                            struct msghdr *msgh, int msg_len)
+{
+        int max, whole, i, offset, over, err;
+        int len, first_len;
+        struct sctp_chunk *chunk;
+        struct sctp_datamsg *msg;
+        struct list_head *pos, *temp;
+        __u8 frag;
+
+        msg = sctp_datamsg_new(GFP_KERNEL);
+        if (!msg)
+                return NULL;
+
+        /* Note: Calculate this outside of the loop, so that all fragments
+         * have the same expiration.
+         */
+        if (sinfo->sinfo_timetolive) {
+                /* sinfo_timetolive is in milliseconds */
+                msg->expires_at = jiffies +
+                                    msecs_to_jiffies(sinfo->sinfo_timetolive);
+                msg->can_abandon = 1;
+                SCTP_DEBUG_PRINTK("%s: msg:%p expires_at: %ld jiffies:%ld\n",
+                                  __FUNCTION__, msg, msg->expires_at, jiffies);
+        }
+
+        max = asoc->frag_point;
+
+        whole = 0;
+        first_len = max;
+
+        /* Encourage Cookie-ECHO bundling. */
+        if (asoc->state < SCTP_STATE_COOKIE_ECHOED) {
+                whole = msg_len / (max - SCTP_ARBITRARY_COOKIE_ECHO_LEN);
+
+                /* Account for the DATA to be bundled with the COOKIE-ECHO. */
+                if (whole) {
+                        first_len = max - SCTP_ARBITRARY_COOKIE_ECHO_LEN;
+                        msg_len -= first_len;
+                        whole = 1;
+                }
+        }
+
+        /* How many full sized?  How many bytes leftover? */
+        whole += msg_len / max;
+        over = msg_len % max;
+        offset = 0;
+
+        if ((whole > 1) || (whole && over))
+                SCTP_INC_STATS_USER(SCTP_MIB_FRAGUSRMSGS);
+
+        /* Create chunks for all the full sized DATA chunks. */
+        for (i=0, len=first_len; i < whole; i++) {
+                frag = SCTP_DATA_MIDDLE_FRAG;
+
+                if (0 == i)
+                        frag |= SCTP_DATA_FIRST_FRAG;
+
+                if ((i == (whole - 1)) && !over)
+                        frag |= SCTP_DATA_LAST_FRAG;
+
+                chunk = sctp_make_datafrag_empty(asoc, sinfo, len, frag, 0);
+
+                if (!chunk)
+                        goto errout;
+                err = sctp_user_addto_chunk(chunk, offset, len, msgh->msg_iov);
+                if (err < 0)
+                        goto errout;
+
+                offset += len;
+
+                /* Put the chunk->skb back into the form expected by send.  */
+                __skb_pull(chunk->skb, (__u8 *)chunk->chunk_hdr
+                           - (__u8 *)chunk->skb->data);
+
+                sctp_datamsg_assign(msg, chunk);
+                list_add_tail(&chunk->frag_list, &msg->chunks);
+
+                /* The first chunk, the first chunk was likely short
+                 * to allow bundling, so reset to full size.
+                 */
+                if (0 == i)
+                        len = max;
+        }
+
+        /* .. now the leftover bytes. */
+        if (over) {
+                if (!whole)
+                        frag = SCTP_DATA_NOT_FRAG;
+                else
+                        frag = SCTP_DATA_LAST_FRAG;
+
+                chunk = sctp_make_datafrag_empty(asoc, sinfo, over, frag, 0);
+
+                if (!chunk)
+                        goto errout;
+
+                err = sctp_user_addto_chunk(chunk, offset, over,msgh->msg_iov);
+
+                /* Put the chunk->skb back into the form expected by send.  */
+                __skb_pull(chunk->skb, (__u8 *)chunk->chunk_hdr
+                           - (__u8 *)chunk->skb->data);
+                if (err < 0)
+                        goto errout;
+
+                sctp_datamsg_assign(msg, chunk);
+                list_add_tail(&chunk->frag_list, &msg->chunks);
+        }
+
+        return msg;
+
+errout:
+        list_for_each_safe(pos, temp, &msg->chunks) {
+                list_del_init(pos);
+                chunk = list_entry(pos, struct sctp_chunk, frag_list);
+                sctp_chunk_free(chunk);
+        }
+        sctp_datamsg_free(msg);
+        return NULL;
+}
+
+/* Check whether this message has expired. */
+int sctp_chunk_abandoned(struct sctp_chunk *chunk)
+{
+        struct sctp_datamsg *msg = chunk->msg;
+
+        if (!msg->can_abandon)
+                return 0;
+
+        if (time_after(jiffies, msg->expires_at))
+                return 1;
+
+        return 0;
+}
+
+/* This chunk (and consequently entire message) has failed in its sending. */
+void sctp_chunk_fail(struct sctp_chunk *chunk, int error)
+{
+        chunk->msg->send_failed = 1;
+        chunk->msg->send_error = error;
+}