* 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 <linux/spinlock.h>
+#include <linux/wait.h>
+#include <asm/bug.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->header[1] = (packet->host->node_id << 16) | (addr >> 32); \
packet->header[2] = addr & 0xffffffff
+#ifndef HPSB_DEBUG_TLABELS
+static
+#endif
+spinlock_t hpsb_tlabel_lock = SPIN_LOCK_UNLOCKED;
+
+static DECLARE_WAIT_QUEUE_HEAD(tlabel_wq);
+
static void fill_async_readquad(struct hpsb_packet *packet, u64 addr)
{
PREP_ASYNC_HEAD_ADDRESS(TCODE_READQ);
packet->tcode = TCODE_ISO_DATA;
}
+/* same as hpsb_get_tlabel, except that it returns immediately */
+static int hpsb_get_tlabel_atomic(struct hpsb_packet *packet)
+{
+ unsigned long flags, *tp;
+ u8 *next;
+ int tlabel, n = NODEID_TO_NODE(packet->node_id);
+
+ /* Broadcast transactions are complete once the request has been sent.
+ * Use the same transaction label for all broadcast transactions. */
+ if (unlikely(n == ALL_NODES)) {
+ packet->tlabel = 0;
+ return 0;
+ }
+ tp = packet->host->tl_pool[n].map;
+ next = &packet->host->next_tl[n];
+
+ spin_lock_irqsave(&hpsb_tlabel_lock, flags);
+ tlabel = find_next_zero_bit(tp, 64, *next);
+ if (tlabel > 63)
+ tlabel = find_first_zero_bit(tp, 64);
+ if (tlabel > 63) {
+ spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
+ return -EAGAIN;
+ }
+ __set_bit(tlabel, tp);
+ *next = (tlabel + 1) & 63;
+ spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
+
+ packet->tlabel = tlabel;
+ return 0;
+}
+
/**
* hpsb_get_tlabel - allocate a transaction label
- * @packet: the packet who's tlabel/tpool we set
+ * @packet: the packet whose tlabel and tl_pool 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
* 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.
+ * tlabel or a signal is received.
*/
int hpsb_get_tlabel(struct hpsb_packet *packet)
{
- unsigned long flags;
- struct hpsb_tlabel_pool *tp;
-
- tp = &packet->host->tpool[packet->node_id & NODE_MASK];
-
- 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;
+ if (irqs_disabled() || in_atomic())
+ return hpsb_get_tlabel_atomic(packet);
+
+ /* NB: The macro wait_event_interruptible() is called with a condition
+ * argument with side effect. This is only possible because the side
+ * effect does not occur until the condition became true, and
+ * wait_event_interruptible() won't evaluate the condition again after
+ * that. */
+ return wait_event_interruptible(tlabel_wq,
+ !hpsb_get_tlabel_atomic(packet));
}
/**
* hpsb_free_tlabel - free an allocated transaction label
- * @packet: packet whos tlabel/tpool needs to be cleared
+ * @packet: packet whose tlabel and tl_pool 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
*/
void hpsb_free_tlabel(struct hpsb_packet *packet)
{
- unsigned long flags;
- struct hpsb_tlabel_pool *tp;
+ unsigned long flags, *tp;
+ int tlabel, n = NODEID_TO_NODE(packet->node_id);
- tp = &packet->host->tpool[packet->node_id & NODE_MASK];
+ if (unlikely(n == ALL_NODES))
+ return;
+ tp = packet->host->tl_pool[n].map;
+ tlabel = packet->tlabel;
+ BUG_ON(tlabel > 63 || tlabel < 0);
- BUG_ON(packet->tlabel > 63 || packet->tlabel < 0);
+ spin_lock_irqsave(&hpsb_tlabel_lock, flags);
+ BUG_ON(!__test_and_clear_bit(tlabel, tp));
+ spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
- 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);
+ wake_up_interruptible(&tlabel_wq);
}
int hpsb_packet_success(struct hpsb_packet *packet)
packet->node_id);
return -EAGAIN;
}
- HPSB_PANIC("reached unreachable code 1 in %s", __FUNCTION__);
+ BUG();
case ACK_BUSY_X:
case ACK_BUSY_A:
packet->ack_code, packet->node_id, packet->tcode);
return -EAGAIN;
}
-
- HPSB_PANIC("reached unreachable code 2 in %s", __FUNCTION__);
+ BUG();
}
struct hpsb_packet *hpsb_make_readpacket(struct hpsb_host *host, nodeid_t node,
git://git.onelab.eu / linux-2.6.git / blobdiff