blob: 988f522475d92429e54fd7e6ddc434d5f77c694e [file] [log] [blame]
/* -----------------------------------------------------------------------------
* Copyright (c) 2011 Ozmo Inc
* Released under the GNU General Public License Version 2 (GPLv2).
* -----------------------------------------------------------------------------
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include "ozconfig.h"
#include "ozprotocol.h"
#include "ozeltbuf.h"
#include "ozpd.h"
#include "oztrace.h"
/*------------------------------------------------------------------------------
*/
#define OZ_ELT_INFO_MAGIC_USED 0x35791057
#define OZ_ELT_INFO_MAGIC_FREE 0x78940102
/*------------------------------------------------------------------------------
* Context: softirq-serialized
*/
int oz_elt_buf_init(struct oz_elt_buf *buf)
{
memset(buf, 0, sizeof(struct oz_elt_buf));
INIT_LIST_HEAD(&buf->stream_list);
INIT_LIST_HEAD(&buf->order_list);
INIT_LIST_HEAD(&buf->isoc_list);
buf->max_free_elts = 32;
spin_lock_init(&buf->lock);
return 0;
}
/*------------------------------------------------------------------------------
* Context: softirq or process
*/
void oz_elt_buf_term(struct oz_elt_buf *buf)
{
struct list_head *e;
int i;
/* Free any elements in the order or isoc lists. */
for (i = 0; i < 2; i++) {
struct list_head *list;
if (i)
list = &buf->order_list;
else
list = &buf->isoc_list;
e = list->next;
while (e != list) {
struct oz_elt_info *ei =
container_of(e, struct oz_elt_info, link_order);
e = e->next;
kfree(ei);
}
}
/* Free any elelment in the pool. */
while (buf->elt_pool) {
struct oz_elt_info *ei =
container_of(buf->elt_pool, struct oz_elt_info, link);
buf->elt_pool = buf->elt_pool->next;
kfree(ei);
}
buf->free_elts = 0;
}
/*------------------------------------------------------------------------------
* Context: softirq or process
*/
struct oz_elt_info *oz_elt_info_alloc(struct oz_elt_buf *buf)
{
struct oz_elt_info *ei = 0;
spin_lock_bh(&buf->lock);
if (buf->free_elts && buf->elt_pool) {
ei = container_of(buf->elt_pool, struct oz_elt_info, link);
buf->elt_pool = ei->link.next;
buf->free_elts--;
spin_unlock_bh(&buf->lock);
if (ei->magic != OZ_ELT_INFO_MAGIC_FREE) {
oz_trace("oz_elt_info_alloc: ei with bad magic: 0x%x\n",
ei->magic);
}
} else {
spin_unlock_bh(&buf->lock);
ei = kmalloc(sizeof(struct oz_elt_info), GFP_ATOMIC);
}
if (ei) {
ei->flags = 0;
ei->app_id = 0;
ei->callback = 0;
ei->context = 0;
ei->stream = 0;
ei->magic = OZ_ELT_INFO_MAGIC_USED;
INIT_LIST_HEAD(&ei->link);
INIT_LIST_HEAD(&ei->link_order);
}
return ei;
}
/*------------------------------------------------------------------------------
* Precondition: oz_elt_buf.lock must be held.
* Context: softirq or process
*/
void oz_elt_info_free(struct oz_elt_buf *buf, struct oz_elt_info *ei)
{
if (ei) {
if (ei->magic == OZ_ELT_INFO_MAGIC_USED) {
buf->free_elts++;
ei->link.next = buf->elt_pool;
buf->elt_pool = &ei->link;
ei->magic = OZ_ELT_INFO_MAGIC_FREE;
} else {
oz_trace("oz_elt_info_free: bad magic ei: %p"
" magic: 0x%x\n",
ei, ei->magic);
}
}
}
/*------------------------------------------------------------------------------
* Context: softirq
*/
void oz_elt_info_free_chain(struct oz_elt_buf *buf, struct list_head *list)
{
struct list_head *e;
e = list->next;
spin_lock_bh(&buf->lock);
while (e != list) {
struct oz_elt_info *ei;
ei = container_of(e, struct oz_elt_info, link);
e = e->next;
oz_elt_info_free(buf, ei);
}
spin_unlock_bh(&buf->lock);
}
/*------------------------------------------------------------------------------
*/
int oz_elt_stream_create(struct oz_elt_buf *buf, u8 id, int max_buf_count)
{
struct oz_elt_stream *st;
oz_trace("oz_elt_stream_create(0x%x)\n", id);
st = kzalloc(sizeof(struct oz_elt_stream), GFP_ATOMIC | __GFP_ZERO);
if (st == 0)
return -ENOMEM;
atomic_set(&st->ref_count, 1);
st->id = id;
st->max_buf_count = max_buf_count;
INIT_LIST_HEAD(&st->elt_list);
spin_lock_bh(&buf->lock);
list_add_tail(&st->link, &buf->stream_list);
spin_unlock_bh(&buf->lock);
return 0;
}
/*------------------------------------------------------------------------------
*/
int oz_elt_stream_delete(struct oz_elt_buf *buf, u8 id)
{
struct list_head *e;
struct oz_elt_stream *st;
oz_trace("oz_elt_stream_delete(0x%x)\n", id);
spin_lock_bh(&buf->lock);
e = buf->stream_list.next;
while (e != &buf->stream_list) {
st = container_of(e, struct oz_elt_stream, link);
if (st->id == id) {
list_del(e);
break;
}
st = 0;
}
if (!st) {
spin_unlock_bh(&buf->lock);
return -1;
}
e = st->elt_list.next;
while (e != &st->elt_list) {
struct oz_elt_info *ei =
container_of(e, struct oz_elt_info, link);
e = e->next;
list_del_init(&ei->link);
list_del_init(&ei->link_order);
st->buf_count -= ei->length;
oz_trace2(OZ_TRACE_STREAM, "Stream down: %d %d %d\n",
st->buf_count,
ei->length, atomic_read(&st->ref_count));
oz_elt_stream_put(st);
oz_elt_info_free(buf, ei);
}
spin_unlock_bh(&buf->lock);
oz_elt_stream_put(st);
return 0;
}
/*------------------------------------------------------------------------------
*/
void oz_elt_stream_get(struct oz_elt_stream *st)
{
atomic_inc(&st->ref_count);
}
/*------------------------------------------------------------------------------
*/
void oz_elt_stream_put(struct oz_elt_stream *st)
{
if (atomic_dec_and_test(&st->ref_count)) {
oz_trace("Stream destroyed\n");
kfree(st);
}
}
/*------------------------------------------------------------------------------
* Precondition: Element buffer lock must be held.
* If this function fails the caller is responsible for deallocating the elt
* info structure.
*/
int oz_queue_elt_info(struct oz_elt_buf *buf, u8 isoc, u8 id,
struct oz_elt_info *ei)
{
struct oz_elt_stream *st = 0;
struct list_head *e;
if (id) {
list_for_each(e, &buf->stream_list) {
st = container_of(e, struct oz_elt_stream, link);
if (st->id == id)
break;
}
if (e == &buf->stream_list) {
/* Stream specified but stream not known so fail.
* Caller deallocates element info. */
return -1;
}
}
if (st) {
/* If this is an ISOC fixed element that needs a frame number
* then insert that now. Earlier we stored the unit count in
* this field.
*/
struct oz_isoc_fixed *body = (struct oz_isoc_fixed *)
&ei->data[sizeof(struct oz_elt)];
if ((body->app_id == OZ_APPID_USB) && (body->type
== OZ_USB_ENDPOINT_DATA) &&
(body->format == OZ_DATA_F_ISOC_FIXED)) {
u8 unit_count = body->frame_number;
body->frame_number = st->frame_number;
st->frame_number += unit_count;
}
/* Claim stream and update accounts */
oz_elt_stream_get(st);
ei->stream = st;
st->buf_count += ei->length;
/* Add to list in stream. */
list_add_tail(&ei->link, &st->elt_list);
oz_trace2(OZ_TRACE_STREAM, "Stream up: %d %d\n",
st->buf_count, ei->length);
/* Check if we have too much buffered for this stream. If so
* start dropping elements until we are back in bounds.
*/
while ((st->buf_count > st->max_buf_count) &&
!list_empty(&st->elt_list)) {
struct oz_elt_info *ei2 =
list_first_entry(&st->elt_list,
struct oz_elt_info, link);
list_del_init(&ei2->link);
list_del_init(&ei2->link_order);
st->buf_count -= ei2->length;
oz_elt_info_free(buf, ei2);
oz_elt_stream_put(st);
}
}
list_add_tail(&ei->link_order, isoc ?
&buf->isoc_list : &buf->order_list);
return 0;
}
/*------------------------------------------------------------------------------
*/
int oz_select_elts_for_tx(struct oz_elt_buf *buf, u8 isoc, unsigned *len,
unsigned max_len, struct list_head *list)
{
int count = 0;
struct list_head *e;
struct list_head *el;
struct oz_elt_info *ei;
spin_lock_bh(&buf->lock);
if (isoc)
el = &buf->isoc_list;
else
el = &buf->order_list;
e = el->next;
while (e != el) {
struct oz_app_hdr *app_hdr;
ei = container_of(e, struct oz_elt_info, link_order);
e = e->next;
if ((*len + ei->length) <= max_len) {
app_hdr = (struct oz_app_hdr *)
&ei->data[sizeof(struct oz_elt)];
app_hdr->elt_seq_num = buf->tx_seq_num[ei->app_id]++;
if (buf->tx_seq_num[ei->app_id] == 0)
buf->tx_seq_num[ei->app_id] = 1;
*len += ei->length;
list_del(&ei->link);
list_del(&ei->link_order);
if (ei->stream) {
ei->stream->buf_count -= ei->length;
oz_trace2(OZ_TRACE_STREAM,
"Stream down: %d %d\n",
ei->stream->buf_count, ei->length);
oz_elt_stream_put(ei->stream);
ei->stream = 0;
}
INIT_LIST_HEAD(&ei->link_order);
list_add_tail(&ei->link, list);
count++;
} else {
break;
}
}
spin_unlock_bh(&buf->lock);
return count;
}
/*------------------------------------------------------------------------------
*/
int oz_are_elts_available(struct oz_elt_buf *buf)
{
return buf->order_list.next != &buf->order_list;
}
/*------------------------------------------------------------------------------
*/
void oz_trim_elt_pool(struct oz_elt_buf *buf)
{
struct list_head *free = 0;
struct list_head *e;
spin_lock_bh(&buf->lock);
while (buf->free_elts > buf->max_free_elts) {
e = buf->elt_pool;
buf->elt_pool = e->next;
e->next = free;
free = e;
buf->free_elts--;
}
spin_unlock_bh(&buf->lock);
while (free) {
struct oz_elt_info *ei =
container_of(free, struct oz_elt_info, link);
free = free->next;
kfree(ei);
}
}