]> rtime.felk.cvut.cz Git - lincan.git/blobdiff - lincan/src/can_quekern.c
LinCAN sources go through big white-space cleanup.
[lincan.git] / lincan / src / can_quekern.c
index 39c033070fa5b042f03d967af53c2db4d944554f..a102ac2a314005923f3ff69af35b40b445ddbbce 100644 (file)
@@ -1,10 +1,35 @@
-/* can_quekern.c - CAN message queues functions for the Linux kernel
- * Linux CAN-bus device driver.
- * New CAN queues by Pavel Pisa - OCERA team member
- * email:pisa@cmp.felk.cvut.cz
- * This software is released under the GPL-License.
- * Version lincan-0.2  9 Jul 2003
- */
+/**************************************************************************/
+/* File: can_quekern.c - CAN message queues functions for the Linux kernel*/
+/*                                                                        */
+/* 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.  */
+/**************************************************************************/
 
 #include "../include/can.h"
 #include "../include/can_sysdep.h"
 extern atomic_t edge_num_cnt;
 
 #ifdef CAN_DEBUG
-       #define DEBUGQUE(fmt,args...) can_printk(KERN_ERR "can_queue (debug): " fmt,\
+       #define DEBUGQUE(fmt,args...) can_printk(KERN_ERR "can_quekern (debug): " fmt,\
        ##args)
 
 #else
        #define DEBUGQUE(fmt,args...)
 #endif
 
-#define ERRMSGQUE(fmt,args...) can_printk(KERN_ERR "can_queue: " fmt,\
+#define ERRMSGQUE(fmt,args...) can_printk(KERN_ERR "can_quekern: " fmt,\
        ##args)
 
 
-/* 
- * Modifies Tx message processing 
+/*
+ * Modifies Tx message processing
  *  0 .. local message processing disabled
  *  1 .. local messages disabled by default but can be enabled by canque_set_filt
  *  2 .. local messages enabled by default, can be disabled by canque_set_filt
@@ -80,12 +105,14 @@ void canque_dead_func(unsigned long data)
                canque_fifo_done_kern(&qedge->fifo);
                kfree(qedge);
        }
-       
+
        can_spin_lock_irqsave(&canque_dead_func_lock, flags);
        entry=canque_dead_ends.next;
        can_spin_unlock_irqrestore(&canque_dead_func_lock,flags);
+       /* lock can be released there, because only one instance of canque_dead_tl
+          can run at once and all other functions add ends only to head */
        while(entry!=&canque_dead_ends){
-               qends=list_entry(canque_dead_ends.next,struct canque_ends_t,dead_peers);
+               qends=list_entry(entry,struct canque_ends_t,dead_peers);
                entry=entry->next;
                if(!list_empty(&qends->inlist))
                        continue;
@@ -106,13 +133,45 @@ void canque_dead_func(unsigned long data)
 
 }
 
+static inline void canque_dead_tasklet_schedule(void)
+{
+    #ifdef CAN_WITH_RTL
+       if(!rtl_rt_system_is_idle()){
+               set_bit(CAN_RTL2LIN_PEND_DEAD_b,&canqueue_rtl2lin_pend);
+               rtl_global_pend_irq (canqueue_rtl_irq);
+               return;
+       }
+    #endif /*CAN_WITH_RTL*/
 
-void canque_edge_do_dead(struct canque_edge_t *edge, int dead_fl)
+       tasklet_schedule(&canque_dead_tl);
+}
+
+
+void canque_edge_do_dead(struct canque_edge_t *edge)
 {
        can_spin_irqflags_t flags;
-       
-       if(dead_fl) return;
-       
+
+       canque_notify_bothends(edge,CANQUEUE_NOTIFY_NOUSR);
+    #ifdef CAN_WITH_RTL
+       /* The problem of the above call is, that in RT-Linux to Linux notify
+          case is edge scheduled for delayed notify delivery, this needs
+          to be reflected there */
+       if(atomic_read(&edge->edge_used)>0){
+               can_spin_lock_irqsave(&edge->inends->ends_lock, flags);
+               can_spin_lock(&edge->outends->ends_lock);
+               if(atomic_read(&edge->edge_used)>0){
+                       /* left edge to live for a while, banshee comes again in a while */
+                       canque_fifo_clear_fl(&edge->fifo,DEAD);
+                       can_spin_unlock(&edge->outends->ends_lock);
+                       can_spin_unlock_irqrestore(&edge->inends->ends_lock, flags);
+                       can_printk(KERN_ERR "can_quertl (debug): canque_edge_do_dead postponed\n");
+                       return;
+               }
+               can_spin_unlock(&edge->outends->ends_lock);
+               can_spin_unlock_irqrestore(&edge->inends->ends_lock, flags);
+       }
+    #endif /*CAN_WITH_RTL*/
+
        if(canqueue_disconnect_edge(edge)<0){
                ERRMSGQUE("canque_edge_do_dead: canqueue_disconnect_edge failed !!!\n");
                return;
@@ -121,7 +180,7 @@ void canque_edge_do_dead(struct canque_edge_t *edge, int dead_fl)
        can_spin_lock_irqsave(&canque_dead_func_lock, flags);
        list_add(&edge->inpeers,&canque_dead_edges);
        can_spin_unlock_irqrestore(&canque_dead_func_lock, flags);
-       tasklet_schedule(&canque_dead_tl);
+       canque_dead_tasklet_schedule();
 }
 
 
@@ -138,8 +197,15 @@ void canque_edge_do_dead(struct canque_edge_t *edge, int dead_fl)
 /**
  * canqueue_notify_kern - notification callback handler for Linux userspace clients
  * @qends: pointer to the callback side ends structure
- * @qedge: edge which invoked notification 
+ * @qedge: edge which invoked notification
  * @what: notification type
+ *
+ * The notification event is handled directly by call of this function except case,
+ * when called from RT-Linux context in mixed mode Linux/RT-Linux compilation.
+ * It is not possible to directly call Linux kernel synchronization primitives
+ * in such case. The notification request is postponed and signaled by @pending_inops flags
+ * by call canqueue_rtl2lin_check_and_pend() function.
+ * The edge reference count is increased until until all pending notifications are processed.
  */
 void canqueue_notify_kern(struct canque_ends_t *qends, struct canque_edge_t *qedge, int what)
 {
@@ -151,7 +217,7 @@ void canqueue_notify_kern(struct canque_ends_t *qends, struct canque_edge_t *qed
                DEBUGQUE("canqueue_notify_kern postponed\n");
                return;
        }
-       
+
        switch(what){
                case CANQUEUE_NOTIFY_EMPTY:
                        wake_up(&qends->endinfo.fileinfo.emptyq);
@@ -162,14 +228,14 @@ void canqueue_notify_kern(struct canque_ends_t *qends, struct canque_edge_t *qed
                        wake_up(&qends->endinfo.fileinfo.writeq);
                    #ifdef CAN_ENABLE_KERN_FASYNC
                        /* Asynchronous I/O processing */
-                       kill_fasync(&qends->endinfo.fileinfo.fasync, SIGIO, POLL_OUT); 
+                       kill_fasync(&qends->endinfo.fileinfo.fasync, SIGIO, POLL_OUT);
                    #endif /*CAN_ENABLE_KERN_FASYNC*/
                        break;
                case CANQUEUE_NOTIFY_PROC:
                        wake_up(&qends->endinfo.fileinfo.readq);
                    #ifdef CAN_ENABLE_KERN_FASYNC
                        /* Asynchronous I/O processing */
-                       kill_fasync(&qends->endinfo.fileinfo.fasync, SIGIO, POLL_IN); 
+                       kill_fasync(&qends->endinfo.fileinfo.fasync, SIGIO, POLL_IN);
                    #endif /*CAN_ENABLE_KERN_FASYNC*/
                        break;
                case CANQUEUE_NOTIFY_NOUSR:
@@ -201,7 +267,7 @@ int canqueue_ends_init_kern(struct canque_ends_t *qends)
     #ifdef CAN_ENABLE_KERN_FASYNC
        qends->endinfo.fileinfo.fasync=NULL;
     #endif /*CAN_ENABLE_KERN_FASYNC*/
-       
+
        qends->notify=canqueue_notify_kern;
        DEBUGQUE("canqueue_ends_init_kern\n");
        return 0;
@@ -227,7 +293,7 @@ int canque_get_inslot4id_wait_kern(struct canque_ends_t *qends,
 {
        int ret=-1;
        DEBUGQUE("canque_get_inslot4id_wait_kern for cmd %d, id %ld, prio %d\n",cmd,id,prio);
-       wait_event_interruptible((qends->endinfo.fileinfo.writeq), 
+       wait_event_interruptible((qends->endinfo.fileinfo.writeq),
                (ret=canque_get_inslot4id(qends,qedgep,slotp,cmd,id,prio))!=-1);
        return ret;
 }
@@ -249,7 +315,7 @@ int canque_get_outslot_wait_kern(struct canque_ends_t *qends,
 {
        int ret=-1;
        DEBUGQUE("canque_get_outslot_wait_kern\n");
-       wait_event_interruptible((qends->endinfo.fileinfo.readq), 
+       wait_event_interruptible((qends->endinfo.fileinfo.readq),
                (ret=canque_test_outslot(qends,qedgep,slotp))!=-1);
        return ret;
 }
@@ -267,7 +333,7 @@ int canque_sync_wait_kern(struct canque_ends_t *qends, struct canque_edge_t *qed
 {
        int ret=-1;
        DEBUGQUE("canque_sync_wait_kern\n");
-       wait_event_interruptible((qends->endinfo.fileinfo.emptyq), 
+       wait_event_interruptible((qends->endinfo.fileinfo.emptyq),
                (ret=canque_fifo_test_fl(&qedge->fifo,EMPTY)?1:0));
        return ret;
 }
@@ -340,7 +406,7 @@ struct canque_edge_t *canque_new_edge_kern(int slotsnr)
 
 #ifdef USE_SYNC_DISCONNECT_EDGE_KERN
 
-/**
+/*not included in doc
  * canqueue_disconnect_edge_kern - disconnect edge from communicating entities with wait
  * @qends: ends structure belonging to calling communication object
  * @qedge: pointer to edge
@@ -356,12 +422,12 @@ int canqueue_disconnect_edge_kern(struct canque_ends_t *qends, struct canque_edg
        DEBUGQUE("canqueue_disconnect_edge_kern %d called\n",qedge->edge_num);
        if(!canque_fifo_test_and_set_fl(&qedge->fifo,DEAD)){
                canque_notify_bothends(qedge, CANQUEUE_NOTIFY_DEAD);
-               
+
                if(atomic_read(&qedge->edge_used)>0)
                        atomic_dec(&qedge->edge_used);
 
                DEBUGQUE("canqueue_disconnect_edge_kern %d waiting\n",qedge->edge_num);
-               wait_event((qends->endinfo.fileinfo.emptyq), 
+               wait_event((qends->endinfo.fileinfo.emptyq),
                        (canqueue_disconnect_edge(qedge)>=0));
 
                /*set_current_state(TASK_UNINTERRUPTIBLE);*/
@@ -410,7 +476,7 @@ int canqueue_disconnect_list_kern(struct canque_ends_t *qends, struct list_head
 int canqueue_ends_sync_all_kern(struct canque_ends_t *qends)
 {
        struct canque_edge_t *qedge;
-       
+
        canque_for_each_inedge(qends, qedge){
                DEBUGQUE("canque_sync_wait_kern called for edge %d\n",qedge->edge_num);
                canque_sync_wait_kern(qends, qedge);
@@ -427,7 +493,7 @@ void canqueue_ends_dispose_postpone(struct canque_ends_t *qends)
        qends->ends_flags |= CAN_ENDSF_DEAD;
        list_add(&qends->dead_peers,&canque_dead_ends);
        can_spin_unlock_irqrestore(&canque_dead_func_lock, flags);
-       tasklet_schedule(&canque_dead_tl);
+       canque_dead_tasklet_schedule();
 }
 
 
@@ -450,7 +516,7 @@ int canqueue_ends_dispose_kern(struct canque_ends_t *qends, int sync)
        /*Wait for sending of all pending messages in the output FIFOs*/
        if(sync)
                canqueue_ends_sync_all_kern(qends);
-       
+
        /* Finish or kill all outgoing edges listed in inends */
        delayed=canqueue_ends_kill_inlist(qends, 1);
        /* Kill all incoming edges listed in outends */