-/* can_queue.h - CAN queues and message passing infrastructure
- * Linux CAN-bus device driver.
- * Written by Pavel Pisa - OCERA team member
- * email:pisa@cmp.felk.cvut.cz
- * This software is released under the GPL-License.
- * Version lincan-0.3 17 Jun 2004
- */
+/**************************************************************************/
+/* File: can_queue.h - CAN queues and message passing infrastructure */
+/* */
+/* LinCAN - (Not only) Linux CAN bus driver */
+/* Copyright (C) 2002-2009 DCE FEE CTU Prague <http://dce.felk.cvut.cz> */
+/* Copyright (C) 2002-2009 Pavel Pisa <pisa@cmp.felk.cvut.cz> */
+/* Funded by OCERA and FRESCOR IST projects */
+/* */
+/* LinCAN is free software; you can redistribute it and/or modify it */
+/* under terms of the GNU General Public License as published by the */
+/* Free Software Foundation; either version 2, or (at your option) any */
+/* later version. LinCAN 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 LinCAN; see file */
+/* COPYING. If not, write to the Free Software Foundation, 675 Mass Ave, */
+/* Cambridge, MA 02139, USA. */
+/* */
+/* To allow use of LinCAN in the compact embedded systems firmware */
+/* and RT-executives (RTEMS for example), main authors agree with next */
+/* special exception: */
+/* */
+/* Including LinCAN header files in a file, instantiating LinCAN generics */
+/* or templates, or linking other files with LinCAN objects to produce */
+/* an application image/executable, does not by itself cause the */
+/* resulting application image/executable to be covered by */
+/* the GNU General Public License. */
+/* This exception does not however invalidate any other reasons */
+/* why the executable file might be covered by the GNU Public License. */
+/* Publication of enhanced or derived LinCAN files is required although. */
+/**************************************************************************/
#ifndef _CAN_QUEUE_H
#define _CAN_QUEUE_H
#include "./can_sysdep.h"
/**
- * struct canque_slot_t - one CAN message slot in the CAN FIFO queue
+ * struct canque_slot_t - one CAN message slot in the CAN FIFO queue
* @next: pointer to the next/younger slot
* @slot_flags: space for flags and optional command describing action
* associated with slot data
* @fifo_flags: this field holds global flags describing state of the FIFO.
* %CAN_FIFOF_ERROR is set when some error condition occurs.
* %CAN_FIFOF_ERR2BLOCK defines, that error should lead to the FIFO block state.
- * %CAN_FIFOF_BLOCK state blocks insertion of the next messages.
- * %CAN_FIFOF_OVERRUN attempt to acquire new slot, when FIFO is full.
- * %CAN_FIFOF_FULL indicates FIFO full state.
+ * %CAN_FIFOF_BLOCK state blocks insertion of the next messages.
+ * %CAN_FIFOF_OVERRUN attempt to acquire new slot, when FIFO is full.
+ * %CAN_FIFOF_FULL indicates FIFO full state.
* %CAN_FIFOF_EMPTY indicates no allocated slot in the FIFO.
* %CAN_FIFOF_DEAD condition indication. Used when FIFO is beeing destroyed.
* @error_code: futher description of error condition
* @fifo_lock: the lock to ensure atomicity of slot manipulation operations.
* @slotsnr: number of allocated slots
*
- * This structure represents CAN FIFO queue. It is implemented as
+ * This structure represents CAN FIFO queue. It is implemented as
* a single linked list of slots prepared for processing. The empty slots
* are stored in single linked list (@flist).
*/
/**
- * canque_fifo_get_inslot - allocate slot for the input of one CAN message
+ * canque_fifo_get_inslot - allocate slot for the input of one CAN message
* @fifo: pointer to the FIFO structure
* @slotp: pointer to location to store pointer to the allocated slot.
* @cmd: optional command associated with allocated slot.
* @pending_inops: bitmask of pending operations
* @pending_outops: bitmask of pending operations
*
- * This structure represents one direction connection from messages source
+ * This structure represents one direction connection from messages source
* (@inends) to message consumer (@outends) fifo ends hub. The edge contains
* &struct canque_fifo_t for message fifo implementation.
*/
* struct canque_ends_t - CAN message delivery subsystem graph vertex (FIFO ends)
* @ends_flags: this field holds flags describing state of the ENDS structure.
* @active: the array of the lists of active edges directed to the ends structure
- * with ready messages. The array is indexed by the edges priorities.
+ * with ready messages. The array is indexed by the edges priorities.
* @idle: the list of the edges directed to the ends structure with empty FIFOs.
* @inlist: the list of outgoing edges input sides.
* @outlist: the list of all incoming edges output sides. Each of there edges
* @ends_lock: the lock synchronizing operations between threads accessing
* same ends structure.
* @notify: pointer to notify procedure. The next state changes are notified.
- * %CANQUEUE_NOTIFY_EMPTY (out->in call) - all slots are processed by FIFO out side.
+ * %CANQUEUE_NOTIFY_EMPTY (out->in call) - all slots are processed by FIFO out side.
* %CANQUEUE_NOTIFY_SPACE (out->in call) - full state negated => there is space for new message.
* %CANQUEUE_NOTIFY_PROC (in->out call) - empty state negated => out side is requested to process slots.
* %CANQUEUE_NOTIFY_NOUSR (both) - notify, that the last user has released the edge usage
int canque_get_inslot(struct canque_ends_t *qends,
struct canque_edge_t **qedgep, struct canque_slot_t **slotp, int cmd);
-
+
int canque_get_inslot4id(struct canque_ends_t *qends,
struct canque_edge_t **qedgep, struct canque_slot_t **slotp,
int cmd, unsigned long id, int prio);
-
+
int canque_put_inslot(struct canque_ends_t *qends,
struct canque_edge_t *qedge, struct canque_slot_t *slot);
int canque_set_filt(struct canque_edge_t *qedge,
unsigned long filtid, unsigned long filtmask, int flags);
-
+
int canque_flush(struct canque_edge_t *qedge);
int canqueue_disconnect_edge(struct canque_edge_t *qedge);
can_spin_lock_irqsave(&outends->ends_lock, flags);
if(outends!=inends) can_spin_lock(&inends->ends_lock);
}
- return flags;
+ return flags;
}
static inline
int dead_fl=0;
struct canque_ends_t *inends=edge->inends;
struct canque_ends_t *outends=edge->outends;
-
+
flags=canque_edge_lock_both_ends(inends, outends);
if(atomic_dec_and_test(&edge->edge_used)) {
dead_fl=!canque_fifo_test_and_set_fl(&edge->fifo,DEAD);
- /* Because of former evolution of edge references
+ /* Because of former evolution of edge references
management notify of CANQUEUE_NOTIFY_NOUSR could
be moved to canque_edge_do_dead :-) */
}
void canque_edge_decref(struct canque_edge_t *edge)
{
int x, y;
-
+
x = atomic_read(&edge->edge_used);
do{
if(x<=1)
return __canque_edge_decref(edge);
y=x;
+ #ifdef CAN_HAVE_ATOMIC_CMPXCHG
+ atomic_cmpxchg(&edge->edge_used, x, x-1);
+ #else /* workaround for case that atomic_cmpxchg is not defined */
/* This code strongly depends on the definition of atomic_t !!!! */
- /* x=cmpxchg(&edge->edge_used, x, x-1); */
- /* Next alternative could be more portable */
x=__cmpxchg(&edge->edge_used, x, x-1, sizeof(atomic_t));
/* If even this does not help, comment out CAN_HAVE_ARCH_CMPXCHG in can_sysdep.h */
+ #endif
} while(x!=y);
}
#endif
can_spin_irqflags_t flags;
struct list_head *entry;
struct canque_edge_t *edge;
-
+
can_spin_lock_irqsave(&qends->ends_lock, flags);
entry=qends->inlist.next;
skip_dead:
can_spin_irqflags_t flags;
struct list_head *entry;
struct canque_edge_t *next;
-
+
can_spin_lock_irqsave(&qends->ends_lock, flags);
entry=edge->inpeers.next;
skip_dead:
can_spin_irqflags_t flags;
struct list_head *entry;
struct canque_edge_t *edge;
-
+
can_spin_lock_irqsave(&qends->ends_lock, flags);
entry=qends->outlist.next;
skip_dead:
can_spin_irqflags_t flags;
struct list_head *entry;
struct canque_edge_t *next;
-
+
can_spin_lock_irqsave(&qends->ends_lock, flags);
entry=edge->outpeers.next;
skip_dead:
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