ieee1394: remove usage of skb_queue as packet queue
This considerably reduces the memory requirements for a packet and
eliminates ieee1394's dependency on CONFIG_NET.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/ieee1394/ieee1394_core.c b/drivers/ieee1394/ieee1394_core.c
index 2708856..d6e3d44 100644
--- a/drivers/ieee1394/ieee1394_core.c
+++ b/drivers/ieee1394/ieee1394_core.c
@@ -30,7 +30,6 @@
#include <linux/moduleparam.h>
#include <linux/bitops.h>
#include <linux/kdev_t.h>
-#include <linux/skbuff.h>
#include <linux/suspend.h>
#include <linux/kthread.h>
#include <linux/preempt.h>
@@ -103,6 +102,8 @@
*
* Set the task that runs when a packet completes. You cannot call this more
* than once on a single packet before it is sent.
+ *
+ * Typically, the complete @routine is responsible to call hpsb_free_packet().
*/
void hpsb_set_packet_complete_task(struct hpsb_packet *packet,
void (*routine)(void *), void *data)
@@ -115,12 +116,12 @@
/**
* hpsb_alloc_packet - allocate new packet structure
- * @data_size: size of the data block to be allocated
+ * @data_size: size of the data block to be allocated, in bytes
*
* This function allocates, initializes and returns a new &struct hpsb_packet.
- * It can be used in interrupt context. A header block is always included, its
- * size is big enough to contain all possible 1394 headers. The data block is
- * only allocated when @data_size is not zero.
+ * It can be used in interrupt context. A header block is always included and
+ * initialized with zeros. Its size is big enough to contain all possible 1394
+ * headers. The data block is only allocated if @data_size is not zero.
*
* For packets for which responses will be received the @data_size has to be big
* enough to contain the response's data block since no further allocation
@@ -135,50 +136,42 @@
*/
struct hpsb_packet *hpsb_alloc_packet(size_t data_size)
{
- struct hpsb_packet *packet = NULL;
- struct sk_buff *skb;
+ struct hpsb_packet *packet;
data_size = ((data_size + 3) & ~3);
- skb = alloc_skb(data_size + sizeof(*packet), GFP_ATOMIC);
- if (skb == NULL)
+ packet = kzalloc(sizeof(*packet) + data_size, GFP_ATOMIC);
+ if (!packet)
return NULL;
- memset(skb->data, 0, data_size + sizeof(*packet));
-
- packet = (struct hpsb_packet *)skb->data;
- packet->skb = skb;
-
- packet->header = packet->embedded_header;
packet->state = hpsb_unused;
packet->generation = -1;
INIT_LIST_HEAD(&packet->driver_list);
+ INIT_LIST_HEAD(&packet->queue);
atomic_set(&packet->refcnt, 1);
if (data_size) {
- packet->data = (quadlet_t *)(skb->data + sizeof(*packet));
- packet->data_size = data_size;
+ packet->data = packet->embedded_data;
+ packet->allocated_data_size = data_size;
}
-
return packet;
}
-
/**
* hpsb_free_packet - free packet and data associated with it
* @packet: packet to free (is NULL safe)
*
- * This function will free packet->data and finally the packet itself.
+ * Frees @packet->data only if it was allocated through hpsb_alloc_packet().
*/
void hpsb_free_packet(struct hpsb_packet *packet)
{
if (packet && atomic_dec_and_test(&packet->refcnt)) {
- BUG_ON(!list_empty(&packet->driver_list));
- kfree_skb(packet->skb);
+ BUG_ON(!list_empty(&packet->driver_list) ||
+ !list_empty(&packet->queue));
+ kfree(packet);
}
}
-
/**
* hpsb_reset_bus - initiate bus reset on the given host
* @host: host controller whose bus to reset
@@ -494,6 +487,8 @@
highlevel_host_reset(host);
}
+static spinlock_t pending_packets_lock = SPIN_LOCK_UNLOCKED;
+
/**
* hpsb_packet_sent - notify core of sending a packet
*
@@ -509,24 +504,24 @@
{
unsigned long flags;
- spin_lock_irqsave(&host->pending_packet_queue.lock, flags);
+ spin_lock_irqsave(&pending_packets_lock, flags);
packet->ack_code = ackcode;
if (packet->no_waiter || packet->state == hpsb_complete) {
/* if packet->no_waiter, must not have a tlabel allocated */
- spin_unlock_irqrestore(&host->pending_packet_queue.lock, flags);
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
hpsb_free_packet(packet);
return;
}
atomic_dec(&packet->refcnt); /* drop HC's reference */
- /* here the packet must be on the host->pending_packet_queue */
+ /* here the packet must be on the host->pending_packets queue */
if (ackcode != ACK_PENDING || !packet->expect_response) {
packet->state = hpsb_complete;
- __skb_unlink(packet->skb, &host->pending_packet_queue);
- spin_unlock_irqrestore(&host->pending_packet_queue.lock, flags);
+ list_del_init(&packet->queue);
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
queue_packet_complete(packet);
return;
}
@@ -534,7 +529,7 @@
packet->state = hpsb_pending;
packet->sendtime = jiffies;
- spin_unlock_irqrestore(&host->pending_packet_queue.lock, flags);
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
mod_timer(&host->timeout, jiffies + host->timeout_interval);
}
@@ -609,12 +604,16 @@
WARN_ON(packet->no_waiter && packet->expect_response);
if (!packet->no_waiter || packet->expect_response) {
+ unsigned long flags;
+
atomic_inc(&packet->refcnt);
/* Set the initial "sendtime" to 10 seconds from now, to
prevent premature expiry. If a packet takes more than
10 seconds to hit the wire, we have bigger problems :) */
packet->sendtime = jiffies + 10 * HZ;
- skb_queue_tail(&host->pending_packet_queue, packet->skb);
+ spin_lock_irqsave(&pending_packets_lock, flags);
+ list_add_tail(&packet->queue, &host->pending_packets);
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
}
if (packet->node_id == host->node_id) {
@@ -690,86 +689,97 @@
}
}
+static size_t packet_size_to_data_size(size_t packet_size, size_t header_size,
+ size_t buffer_size, int tcode)
+{
+ size_t ret = packet_size <= header_size ? 0 : packet_size - header_size;
+
+ if (unlikely(ret > buffer_size))
+ ret = buffer_size;
+
+ if (unlikely(ret + header_size != packet_size))
+ HPSB_ERR("unexpected packet size %d (tcode %d), bug?",
+ packet_size, tcode);
+ return ret;
+}
static void handle_packet_response(struct hpsb_host *host, int tcode,
quadlet_t *data, size_t size)
{
- struct hpsb_packet *packet = NULL;
- struct sk_buff *skb;
- int tcode_match = 0;
- int tlabel;
+ struct hpsb_packet *packet;
+ int tlabel = (data[0] >> 10) & 0x3f;
+ size_t header_size;
unsigned long flags;
- tlabel = (data[0] >> 10) & 0x3f;
+ spin_lock_irqsave(&pending_packets_lock, flags);
- spin_lock_irqsave(&host->pending_packet_queue.lock, flags);
+ list_for_each_entry(packet, &host->pending_packets, queue)
+ if (packet->tlabel == tlabel &&
+ packet->node_id == (data[1] >> 16))
+ goto found;
- skb_queue_walk(&host->pending_packet_queue, skb) {
- packet = (struct hpsb_packet *)skb->data;
- if ((packet->tlabel == tlabel)
- && (packet->node_id == (data[1] >> 16))){
- break;
- }
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
+ HPSB_DEBUG("unsolicited response packet received - %s",
+ "no tlabel match");
+ dump_packet("contents", data, 16, -1);
+ return;
- packet = NULL;
- }
-
- if (packet == NULL) {
- HPSB_DEBUG("unsolicited response packet received - no tlabel match");
- dump_packet("contents", data, 16, -1);
- spin_unlock_irqrestore(&host->pending_packet_queue.lock, flags);
- return;
- }
-
+found:
switch (packet->tcode) {
case TCODE_WRITEQ:
case TCODE_WRITEB:
- if (tcode != TCODE_WRITE_RESPONSE)
+ if (unlikely(tcode != TCODE_WRITE_RESPONSE))
break;
- tcode_match = 1;
- memcpy(packet->header, data, 12);
- break;
+ header_size = 12;
+ size = 0;
+ goto dequeue;
+
case TCODE_READQ:
- if (tcode != TCODE_READQ_RESPONSE)
+ if (unlikely(tcode != TCODE_READQ_RESPONSE))
break;
- tcode_match = 1;
- memcpy(packet->header, data, 16);
- break;
+ header_size = 16;
+ size = 0;
+ goto dequeue;
+
case TCODE_READB:
- if (tcode != TCODE_READB_RESPONSE)
+ if (unlikely(tcode != TCODE_READB_RESPONSE))
break;
- tcode_match = 1;
- BUG_ON(packet->skb->len - sizeof(*packet) < size - 16);
- memcpy(packet->header, data, 16);
- memcpy(packet->data, data + 4, size - 16);
- break;
+ header_size = 16;
+ size = packet_size_to_data_size(size, header_size,
+ packet->allocated_data_size,
+ tcode);
+ goto dequeue;
+
case TCODE_LOCK_REQUEST:
- if (tcode != TCODE_LOCK_RESPONSE)
+ if (unlikely(tcode != TCODE_LOCK_RESPONSE))
break;
- tcode_match = 1;
- size = min((size - 16), (size_t)8);
- BUG_ON(packet->skb->len - sizeof(*packet) < size);
- memcpy(packet->header, data, 16);
- memcpy(packet->data, data + 4, size);
- break;
+ header_size = 16;
+ size = packet_size_to_data_size(min(size, (size_t)(16 + 8)),
+ header_size,
+ packet->allocated_data_size,
+ tcode);
+ goto dequeue;
}
- if (!tcode_match) {
- spin_unlock_irqrestore(&host->pending_packet_queue.lock, flags);
- HPSB_INFO("unsolicited response packet received - tcode mismatch");
- dump_packet("contents", data, 16, -1);
- return;
- }
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
+ HPSB_DEBUG("unsolicited response packet received - %s",
+ "tcode mismatch");
+ dump_packet("contents", data, 16, -1);
+ return;
- __skb_unlink(skb, &host->pending_packet_queue);
+dequeue:
+ list_del_init(&packet->queue);
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
if (packet->state == hpsb_queued) {
packet->sendtime = jiffies;
packet->ack_code = ACK_PENDING;
}
-
packet->state = hpsb_complete;
- spin_unlock_irqrestore(&host->pending_packet_queue.lock, flags);
+
+ memcpy(packet->header, data, header_size);
+ if (size)
+ memcpy(packet->data, data + 4, size);
queue_packet_complete(packet);
}
@@ -783,6 +793,7 @@
p = hpsb_alloc_packet(dsize);
if (unlikely(p == NULL)) {
/* FIXME - send data_error response */
+ HPSB_ERR("out of memory, cannot send response packet");
return NULL;
}
@@ -832,7 +843,6 @@
static void fill_async_write_resp(struct hpsb_packet *packet, int rcode)
{
PREP_ASYNC_HEAD_RCODE(TCODE_WRITE_RESPONSE);
- packet->header[2] = 0;
packet->header_size = 12;
packet->data_size = 0;
}
@@ -1002,8 +1012,8 @@
{
int tcode;
- if (host->in_bus_reset) {
- HPSB_INFO("received packet during reset; ignoring");
+ if (unlikely(host->in_bus_reset)) {
+ HPSB_DEBUG("received packet during reset; ignoring");
return;
}
@@ -1037,23 +1047,27 @@
break;
default:
- HPSB_NOTICE("received packet with bogus transaction code %d",
- tcode);
+ HPSB_DEBUG("received packet with bogus transaction code %d",
+ tcode);
break;
}
}
-
static void abort_requests(struct hpsb_host *host)
{
- struct hpsb_packet *packet;
- struct sk_buff *skb;
+ struct hpsb_packet *packet, *p;
+ struct list_head tmp;
+ unsigned long flags;
host->driver->devctl(host, CANCEL_REQUESTS, 0);
- while ((skb = skb_dequeue(&host->pending_packet_queue)) != NULL) {
- packet = (struct hpsb_packet *)skb->data;
+ INIT_LIST_HEAD(&tmp);
+ spin_lock_irqsave(&pending_packets_lock, flags);
+ list_splice_init(&host->pending_packets, &tmp);
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
+ list_for_each_entry_safe(packet, p, &tmp, queue) {
+ list_del_init(&packet->queue);
packet->state = hpsb_complete;
packet->ack_code = ACKX_ABORTED;
queue_packet_complete(packet);
@@ -1063,87 +1077,90 @@
void abort_timedouts(unsigned long __opaque)
{
struct hpsb_host *host = (struct hpsb_host *)__opaque;
- unsigned long flags;
- struct hpsb_packet *packet;
- struct sk_buff *skb;
- unsigned long expire;
+ struct hpsb_packet *packet, *p;
+ struct list_head tmp;
+ unsigned long flags, expire, j;
spin_lock_irqsave(&host->csr.lock, flags);
expire = host->csr.expire;
spin_unlock_irqrestore(&host->csr.lock, flags);
- /* Hold the lock around this, since we aren't dequeuing all
- * packets, just ones we need. */
- spin_lock_irqsave(&host->pending_packet_queue.lock, flags);
+ j = jiffies;
+ INIT_LIST_HEAD(&tmp);
+ spin_lock_irqsave(&pending_packets_lock, flags);
- while (!skb_queue_empty(&host->pending_packet_queue)) {
- skb = skb_peek(&host->pending_packet_queue);
-
- packet = (struct hpsb_packet *)skb->data;
-
- if (time_before(packet->sendtime + expire, jiffies)) {
- __skb_unlink(skb, &host->pending_packet_queue);
- packet->state = hpsb_complete;
- packet->ack_code = ACKX_TIMEOUT;
- queue_packet_complete(packet);
- } else {
+ list_for_each_entry_safe(packet, p, &host->pending_packets, queue) {
+ if (time_before(packet->sendtime + expire, j))
+ list_move_tail(&packet->queue, &tmp);
+ else
/* Since packets are added to the tail, the oldest
* ones are first, always. When we get to one that
* isn't timed out, the rest aren't either. */
break;
- }
}
+ if (!list_empty(&host->pending_packets))
+ mod_timer(&host->timeout, j + host->timeout_interval);
- if (!skb_queue_empty(&host->pending_packet_queue))
- mod_timer(&host->timeout, jiffies + host->timeout_interval);
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
- spin_unlock_irqrestore(&host->pending_packet_queue.lock, flags);
+ list_for_each_entry_safe(packet, p, &tmp, queue) {
+ list_del_init(&packet->queue);
+ packet->state = hpsb_complete;
+ packet->ack_code = ACKX_TIMEOUT;
+ queue_packet_complete(packet);
+ }
}
-
-/* Kernel thread and vars, which handles packets that are completed. Only
- * packets that have a "complete" function are sent here. This way, the
- * completion is run out of kernel context, and doesn't block the rest of
- * the stack. */
static struct task_struct *khpsbpkt_thread;
-static struct sk_buff_head hpsbpkt_queue;
+static LIST_HEAD(hpsbpkt_queue);
static void queue_packet_complete(struct hpsb_packet *packet)
{
+ unsigned long flags;
+
if (packet->no_waiter) {
hpsb_free_packet(packet);
return;
}
if (packet->complete_routine != NULL) {
- skb_queue_tail(&hpsbpkt_queue, packet->skb);
+ spin_lock_irqsave(&pending_packets_lock, flags);
+ list_add_tail(&packet->queue, &hpsbpkt_queue);
+ spin_unlock_irqrestore(&pending_packets_lock, flags);
wake_up_process(khpsbpkt_thread);
}
return;
}
+/*
+ * Kernel thread which handles packets that are completed. This way the
+ * packet's "complete" function is asynchronously run in process context.
+ * Only packets which have a "complete" function may be sent here.
+ */
static int hpsbpkt_thread(void *__hi)
{
- struct sk_buff *skb;
- struct hpsb_packet *packet;
- void (*complete_routine)(void*);
- void *complete_data;
+ struct hpsb_packet *packet, *p;
+ struct list_head tmp;
+ int may_schedule;
current->flags |= PF_NOFREEZE;
while (!kthread_should_stop()) {
- while ((skb = skb_dequeue(&hpsbpkt_queue)) != NULL) {
- packet = (struct hpsb_packet *)skb->data;
- complete_routine = packet->complete_routine;
- complete_data = packet->complete_data;
+ INIT_LIST_HEAD(&tmp);
+ spin_lock_irq(&pending_packets_lock);
+ list_splice_init(&hpsbpkt_queue, &tmp);
+ spin_unlock_irq(&pending_packets_lock);
- packet->complete_routine = packet->complete_data = NULL;
-
- complete_routine(complete_data);
+ list_for_each_entry_safe(packet, p, &tmp, queue) {
+ list_del_init(&packet->queue);
+ packet->complete_routine(packet->complete_data);
}
set_current_state(TASK_INTERRUPTIBLE);
- if (!skb_peek(&hpsbpkt_queue))
+ spin_lock_irq(&pending_packets_lock);
+ may_schedule = list_empty(&hpsbpkt_queue);
+ spin_unlock_irq(&pending_packets_lock);
+ if (may_schedule)
schedule();
__set_current_state(TASK_RUNNING);
}
@@ -1154,8 +1171,6 @@
{
int i, ret;
- skb_queue_head_init(&hpsbpkt_queue);
-
/* non-fatal error */
if (hpsb_init_config_roms()) {
HPSB_ERR("Failed to initialize some config rom entries.\n");