linux/drivers/ieee1394/ieee1394_transactions.c
Ben Collins eaf88450d2 ieee1394: save RAM by using a single tlabel for broadcast transactions
Since broadcast transactions are already complete when the request has
been sent, the same transaction label can be reused all over again, see
IEEE 1394 7.3.2.5 and 6.2.4.3.  Therefore we can reduce the footprint
of struct hpsb_host by the size of one struct hpsb_tlabel_pool.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Ben Collins <bcollins@ubuntu.com>
2006-06-12 18:12:49 -04:00

614 lines
14 KiB
C

/*
* IEEE 1394 for Linux
*
* Transaction support.
*
* Copyright (C) 1999 Andreas E. Bombe
*
* This code is licensed under the GPL. See the file COPYING in the root
* directory of the kernel sources for details.
*/
#include <linux/sched.h>
#include <linux/bitops.h>
#include <linux/smp_lock.h>
#include <linux/interrupt.h>
#include <asm/errno.h>
#include "ieee1394.h"
#include "ieee1394_types.h"
#include "hosts.h"
#include "ieee1394_core.h"
#include "highlevel.h"
#include "nodemgr.h"
#include "ieee1394_transactions.h"
#define PREP_ASYNC_HEAD_ADDRESS(tc) \
packet->tcode = tc; \
packet->header[0] = (packet->node_id << 16) | (packet->tlabel << 10) \
| (1 << 8) | (tc << 4); \
packet->header[1] = (packet->host->node_id << 16) | (addr >> 32); \
packet->header[2] = addr & 0xffffffff
static void fill_async_readquad(struct hpsb_packet *packet, u64 addr)
{
PREP_ASYNC_HEAD_ADDRESS(TCODE_READQ);
packet->header_size = 12;
packet->data_size = 0;
packet->expect_response = 1;
}
static void fill_async_readblock(struct hpsb_packet *packet, u64 addr,
int length)
{
PREP_ASYNC_HEAD_ADDRESS(TCODE_READB);
packet->header[3] = length << 16;
packet->header_size = 16;
packet->data_size = 0;
packet->expect_response = 1;
}
static void fill_async_writequad(struct hpsb_packet *packet, u64 addr,
quadlet_t data)
{
PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEQ);
packet->header[3] = data;
packet->header_size = 16;
packet->data_size = 0;
packet->expect_response = 1;
}
static void fill_async_writeblock(struct hpsb_packet *packet, u64 addr,
int length)
{
PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEB);
packet->header[3] = length << 16;
packet->header_size = 16;
packet->expect_response = 1;
packet->data_size = length + (length % 4 ? 4 - (length % 4) : 0);
}
static void fill_async_lock(struct hpsb_packet *packet, u64 addr, int extcode,
int length)
{
PREP_ASYNC_HEAD_ADDRESS(TCODE_LOCK_REQUEST);
packet->header[3] = (length << 16) | extcode;
packet->header_size = 16;
packet->data_size = length;
packet->expect_response = 1;
}
static void fill_iso_packet(struct hpsb_packet *packet, int length, int channel,
int tag, int sync)
{
packet->header[0] = (length << 16) | (tag << 14) | (channel << 8)
| (TCODE_ISO_DATA << 4) | sync;
packet->header_size = 4;
packet->data_size = length;
packet->type = hpsb_iso;
packet->tcode = TCODE_ISO_DATA;
}
static void fill_phy_packet(struct hpsb_packet *packet, quadlet_t data)
{
packet->header[0] = data;
packet->header[1] = ~data;
packet->header_size = 8;
packet->data_size = 0;
packet->expect_response = 0;
packet->type = hpsb_raw; /* No CRC added */
packet->speed_code = IEEE1394_SPEED_100; /* Force speed to be 100Mbps */
}
static void fill_async_stream_packet(struct hpsb_packet *packet, int length,
int channel, int tag, int sync)
{
packet->header[0] = (length << 16) | (tag << 14) | (channel << 8)
| (TCODE_STREAM_DATA << 4) | sync;
packet->header_size = 4;
packet->data_size = length;
packet->type = hpsb_async;
packet->tcode = TCODE_ISO_DATA;
}
/**
* hpsb_get_tlabel - allocate a transaction label
* @packet: the packet who's tlabel/tpool we set
*
* Every asynchronous transaction on the 1394 bus needs a transaction
* label to match the response to the request. This label has to be
* different from any other transaction label in an outstanding request to
* the same node to make matching possible without ambiguity.
*
* There are 64 different tlabels, so an allocated tlabel has to be freed
* with hpsb_free_tlabel() after the transaction is complete (unless it's
* reused again for the same target node).
*
* Return value: Zero on success, otherwise non-zero. A non-zero return
* generally means there are no available tlabels. If this is called out
* of interrupt or atomic context, then it will sleep until can return a
* tlabel.
*/
int hpsb_get_tlabel(struct hpsb_packet *packet)
{
unsigned long flags;
struct hpsb_tlabel_pool *tp;
int n = NODEID_TO_NODE(packet->node_id);
if (unlikely(n == ALL_NODES))
return 0;
tp = &packet->host->tpool[n];
if (irqs_disabled() || in_atomic()) {
if (down_trylock(&tp->count))
return 1;
} else {
down(&tp->count);
}
spin_lock_irqsave(&tp->lock, flags);
packet->tlabel = find_next_zero_bit(tp->pool, 64, tp->next);
if (packet->tlabel > 63)
packet->tlabel = find_first_zero_bit(tp->pool, 64);
tp->next = (packet->tlabel + 1) % 64;
/* Should _never_ happen */
BUG_ON(test_and_set_bit(packet->tlabel, tp->pool));
tp->allocations++;
spin_unlock_irqrestore(&tp->lock, flags);
return 0;
}
/**
* hpsb_free_tlabel - free an allocated transaction label
* @packet: packet whos tlabel/tpool needs to be cleared
*
* Frees the transaction label allocated with hpsb_get_tlabel(). The
* tlabel has to be freed after the transaction is complete (i.e. response
* was received for a split transaction or packet was sent for a unified
* transaction).
*
* A tlabel must not be freed twice.
*/
void hpsb_free_tlabel(struct hpsb_packet *packet)
{
unsigned long flags;
struct hpsb_tlabel_pool *tp;
int n = NODEID_TO_NODE(packet->node_id);
if (unlikely(n == ALL_NODES))
return;
tp = &packet->host->tpool[n];
BUG_ON(packet->tlabel > 63 || packet->tlabel < 0);
spin_lock_irqsave(&tp->lock, flags);
BUG_ON(!test_and_clear_bit(packet->tlabel, tp->pool));
spin_unlock_irqrestore(&tp->lock, flags);
up(&tp->count);
}
int hpsb_packet_success(struct hpsb_packet *packet)
{
switch (packet->ack_code) {
case ACK_PENDING:
switch ((packet->header[1] >> 12) & 0xf) {
case RCODE_COMPLETE:
return 0;
case RCODE_CONFLICT_ERROR:
return -EAGAIN;
case RCODE_DATA_ERROR:
return -EREMOTEIO;
case RCODE_TYPE_ERROR:
return -EACCES;
case RCODE_ADDRESS_ERROR:
return -EINVAL;
default:
HPSB_ERR("received reserved rcode %d from node %d",
(packet->header[1] >> 12) & 0xf,
packet->node_id);
return -EAGAIN;
}
HPSB_PANIC("reached unreachable code 1 in %s", __FUNCTION__);
case ACK_BUSY_X:
case ACK_BUSY_A:
case ACK_BUSY_B:
return -EBUSY;
case ACK_TYPE_ERROR:
return -EACCES;
case ACK_COMPLETE:
if (packet->tcode == TCODE_WRITEQ
|| packet->tcode == TCODE_WRITEB) {
return 0;
} else {
HPSB_ERR("impossible ack_complete from node %d "
"(tcode %d)", packet->node_id, packet->tcode);
return -EAGAIN;
}
case ACK_DATA_ERROR:
if (packet->tcode == TCODE_WRITEB
|| packet->tcode == TCODE_LOCK_REQUEST) {
return -EAGAIN;
} else {
HPSB_ERR("impossible ack_data_error from node %d "
"(tcode %d)", packet->node_id, packet->tcode);
return -EAGAIN;
}
case ACK_ADDRESS_ERROR:
return -EINVAL;
case ACK_TARDY:
case ACK_CONFLICT_ERROR:
case ACKX_NONE:
case ACKX_SEND_ERROR:
case ACKX_ABORTED:
case ACKX_TIMEOUT:
/* error while sending */
return -EAGAIN;
default:
HPSB_ERR("got invalid ack %d from node %d (tcode %d)",
packet->ack_code, packet->node_id, packet->tcode);
return -EAGAIN;
}
HPSB_PANIC("reached unreachable code 2 in %s", __FUNCTION__);
}
struct hpsb_packet *hpsb_make_readpacket(struct hpsb_host *host, nodeid_t node,
u64 addr, size_t length)
{
struct hpsb_packet *packet;
if (length == 0)
return NULL;
packet = hpsb_alloc_packet(length);
if (!packet)
return NULL;
packet->host = host;
packet->node_id = node;
if (hpsb_get_tlabel(packet)) {
hpsb_free_packet(packet);
return NULL;
}
if (length == 4)
fill_async_readquad(packet, addr);
else
fill_async_readblock(packet, addr, length);
return packet;
}
struct hpsb_packet *hpsb_make_writepacket(struct hpsb_host *host, nodeid_t node,
u64 addr, quadlet_t * buffer,
size_t length)
{
struct hpsb_packet *packet;
if (length == 0)
return NULL;
packet = hpsb_alloc_packet(length);
if (!packet)
return NULL;
if (length % 4) { /* zero padding bytes */
packet->data[length >> 2] = 0;
}
packet->host = host;
packet->node_id = node;
if (hpsb_get_tlabel(packet)) {
hpsb_free_packet(packet);
return NULL;
}
if (length == 4) {
fill_async_writequad(packet, addr, buffer ? *buffer : 0);
} else {
fill_async_writeblock(packet, addr, length);
if (buffer)
memcpy(packet->data, buffer, length);
}
return packet;
}
struct hpsb_packet *hpsb_make_streampacket(struct hpsb_host *host, u8 * buffer,
int length, int channel, int tag,
int sync)
{
struct hpsb_packet *packet;
if (length == 0)
return NULL;
packet = hpsb_alloc_packet(length);
if (!packet)
return NULL;
if (length % 4) { /* zero padding bytes */
packet->data[length >> 2] = 0;
}
packet->host = host;
if (hpsb_get_tlabel(packet)) {
hpsb_free_packet(packet);
return NULL;
}
fill_async_stream_packet(packet, length, channel, tag, sync);
if (buffer)
memcpy(packet->data, buffer, length);
return packet;
}
struct hpsb_packet *hpsb_make_lockpacket(struct hpsb_host *host, nodeid_t node,
u64 addr, int extcode,
quadlet_t * data, quadlet_t arg)
{
struct hpsb_packet *p;
u32 length;
p = hpsb_alloc_packet(8);
if (!p)
return NULL;
p->host = host;
p->node_id = node;
if (hpsb_get_tlabel(p)) {
hpsb_free_packet(p);
return NULL;
}
switch (extcode) {
case EXTCODE_FETCH_ADD:
case EXTCODE_LITTLE_ADD:
length = 4;
if (data)
p->data[0] = *data;
break;
default:
length = 8;
if (data) {
p->data[0] = arg;
p->data[1] = *data;
}
break;
}
fill_async_lock(p, addr, extcode, length);
return p;
}
struct hpsb_packet *hpsb_make_lock64packet(struct hpsb_host *host,
nodeid_t node, u64 addr, int extcode,
octlet_t * data, octlet_t arg)
{
struct hpsb_packet *p;
u32 length;
p = hpsb_alloc_packet(16);
if (!p)
return NULL;
p->host = host;
p->node_id = node;
if (hpsb_get_tlabel(p)) {
hpsb_free_packet(p);
return NULL;
}
switch (extcode) {
case EXTCODE_FETCH_ADD:
case EXTCODE_LITTLE_ADD:
length = 8;
if (data) {
p->data[0] = *data >> 32;
p->data[1] = *data & 0xffffffff;
}
break;
default:
length = 16;
if (data) {
p->data[0] = arg >> 32;
p->data[1] = arg & 0xffffffff;
p->data[2] = *data >> 32;
p->data[3] = *data & 0xffffffff;
}
break;
}
fill_async_lock(p, addr, extcode, length);
return p;
}
struct hpsb_packet *hpsb_make_phypacket(struct hpsb_host *host, quadlet_t data)
{
struct hpsb_packet *p;
p = hpsb_alloc_packet(0);
if (!p)
return NULL;
p->host = host;
fill_phy_packet(p, data);
return p;
}
struct hpsb_packet *hpsb_make_isopacket(struct hpsb_host *host,
int length, int channel,
int tag, int sync)
{
struct hpsb_packet *p;
p = hpsb_alloc_packet(length);
if (!p)
return NULL;
p->host = host;
fill_iso_packet(p, length, channel, tag, sync);
p->generation = get_hpsb_generation(host);
return p;
}
/*
* FIXME - these functions should probably read from / write to user space to
* avoid in kernel buffers for user space callers
*/
int hpsb_read(struct hpsb_host *host, nodeid_t node, unsigned int generation,
u64 addr, quadlet_t * buffer, size_t length)
{
struct hpsb_packet *packet;
int retval = 0;
if (length == 0)
return -EINVAL;
BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
packet = hpsb_make_readpacket(host, node, addr, length);
if (!packet) {
return -ENOMEM;
}
packet->generation = generation;
retval = hpsb_send_packet_and_wait(packet);
if (retval < 0)
goto hpsb_read_fail;
retval = hpsb_packet_success(packet);
if (retval == 0) {
if (length == 4) {
*buffer = packet->header[3];
} else {
memcpy(buffer, packet->data, length);
}
}
hpsb_read_fail:
hpsb_free_tlabel(packet);
hpsb_free_packet(packet);
return retval;
}
int hpsb_write(struct hpsb_host *host, nodeid_t node, unsigned int generation,
u64 addr, quadlet_t * buffer, size_t length)
{
struct hpsb_packet *packet;
int retval;
if (length == 0)
return -EINVAL;
BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
packet = hpsb_make_writepacket(host, node, addr, buffer, length);
if (!packet)
return -ENOMEM;
packet->generation = generation;
retval = hpsb_send_packet_and_wait(packet);
if (retval < 0)
goto hpsb_write_fail;
retval = hpsb_packet_success(packet);
hpsb_write_fail:
hpsb_free_tlabel(packet);
hpsb_free_packet(packet);
return retval;
}
#if 0
int hpsb_lock(struct hpsb_host *host, nodeid_t node, unsigned int generation,
u64 addr, int extcode, quadlet_t * data, quadlet_t arg)
{
struct hpsb_packet *packet;
int retval = 0;
BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
packet = hpsb_make_lockpacket(host, node, addr, extcode, data, arg);
if (!packet)
return -ENOMEM;
packet->generation = generation;
retval = hpsb_send_packet_and_wait(packet);
if (retval < 0)
goto hpsb_lock_fail;
retval = hpsb_packet_success(packet);
if (retval == 0) {
*data = packet->data[0];
}
hpsb_lock_fail:
hpsb_free_tlabel(packet);
hpsb_free_packet(packet);
return retval;
}
int hpsb_send_gasp(struct hpsb_host *host, int channel, unsigned int generation,
quadlet_t * buffer, size_t length, u32 specifier_id,
unsigned int version)
{
struct hpsb_packet *packet;
int retval = 0;
u16 specifier_id_hi = (specifier_id & 0x00ffff00) >> 8;
u8 specifier_id_lo = specifier_id & 0xff;
HPSB_VERBOSE("Send GASP: channel = %d, length = %Zd", channel, length);
length += 8;
packet = hpsb_make_streampacket(host, NULL, length, channel, 3, 0);
if (!packet)
return -ENOMEM;
packet->data[0] = cpu_to_be32((host->node_id << 16) | specifier_id_hi);
packet->data[1] =
cpu_to_be32((specifier_id_lo << 24) | (version & 0x00ffffff));
memcpy(&(packet->data[2]), buffer, length - 8);
packet->generation = generation;
packet->no_waiter = 1;
retval = hpsb_send_packet(packet);
if (retval < 0)
hpsb_free_packet(packet);
return retval;
}
#endif /* 0 */