+++ /dev/null
-/* 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-0.3 17 Jun 2004
- */
-
-#include "../include/can.h"
-#include "../include/can_sysdep.h"
-#include "../include/can_queue.h"
-
-//#define CAN_DEBUG
-
-extern atomic_t edge_num_cnt;
-
-#ifdef CAN_DEBUG
- #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_quekern: " fmt,\
- ##args)
-
-
-/*
- * 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
- */
-extern int processlocal;
-
-void canque_dead_func(unsigned long data);
-
-/* Support for dead ends structures left after client close */
-can_spinlock_t canque_dead_func_lock;
-LIST_HEAD(canque_dead_ends);
-/* retrieved by list_entry(canque_dead_ends.next,struct canque_ends_t,dead_peers) */
-LIST_HEAD(canque_dead_edges);
-/* retrieved by list_entry(canque_dead_edges.next,struct canque_edge_t,inpeers) */
-DECLARE_TASKLET(canque_dead_tl, canque_dead_func, 0);
-/* activated by tasklet_schedule(&canque_dead_tl) */
-
-
-static inline
-struct canque_edge_t *canque_dead_edges_cut_first(void)
-{
- can_spin_irqflags_t flags;
- struct canque_edge_t *edge;
- can_spin_lock_irqsave(&canque_dead_func_lock, flags);
- if(list_empty(&canque_dead_edges))
- edge=NULL;
- else{
- edge=list_entry(canque_dead_edges.next,struct canque_edge_t,inpeers);
- list_del(&edge->inpeers);
- }
- can_spin_unlock_irqrestore(&canque_dead_func_lock, flags);
- return edge;
-}
-
-void canque_dead_func(unsigned long data)
-{
- can_spin_irqflags_t flags;
- struct canque_edge_t *qedge;
- struct canque_ends_t *qends;
- struct list_head *entry;
-
- while((qedge=canque_dead_edges_cut_first())){
- DEBUGQUE("edge %d disposed\n",qedge->edge_num);
- #ifdef CAN_WITH_RTL
- if(canque_fifo_test_fl(&qedge->fifo,RTL_MEM)){
- canque_dispose_edge_rtl(qedge);
- continue;
- }
- #endif /*CAN_WITH_RTL*/
- 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(entry,struct canque_ends_t,dead_peers);
- entry=entry->next;
- if(!list_empty(&qends->inlist))
- continue;
- if(!list_empty(&qends->outlist))
- continue;
- can_spin_lock_irqsave(&canque_dead_func_lock, flags);
- list_del(&qends->dead_peers);
- can_spin_unlock_irqrestore(&canque_dead_func_lock,flags);
- DEBUGQUE("ends structure disposed\n");
- #ifdef CAN_WITH_RTL
- if(qends->ends_flags&CAN_ENDSF_MEM_RTL){
- canque_ends_free_rtl(qends);
- continue;
- }
- #endif /*CAN_WITH_RTL*/
- kfree(qends);
- }
-
-}
-
-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*/
-
- tasklet_schedule(&canque_dead_tl);
-}
-
-
-void canque_edge_do_dead(struct canque_edge_t *edge)
-{
- can_spin_irqflags_t flags;
-
- 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;
- }
-
- 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);
- canque_dead_tasklet_schedule();
-}
-
-
-
-/*if(qends->ends_flags & CAN_ENDSF_DEAD){
- can_spin_lock_irqsave(&canque_dead_func_lock, flags);
- list_del(&qends->dead_peers);
- list_add(&qends->dead_peers,&canque_dead_ends);
- can_spin_unlock_irqrestore(&canque_dead_func_lock, flags);
- tasklet_schedule(&canque_dead_tl);
-}*/
-
-
-/**
- * canqueue_notify_kern - notification callback handler for Linux userspace clients
- * @qends: pointer to the callback side ends structure
- * @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)
-{
- DEBUGQUE("canqueue_notify_kern for edge %d, use %d and event %d\n",
- qedge->edge_num,(int)atomic_read(&qedge->edge_used),what);
-
- /* delay event delivery for RT-Linux -> kernel notifications */
- if(canqueue_rtl2lin_check_and_pend(qends,qedge,what)){
- DEBUGQUE("canqueue_notify_kern postponed\n");
- return;
- }
-
- switch(what){
- case CANQUEUE_NOTIFY_EMPTY:
- wake_up(&qends->endinfo.fileinfo.emptyq);
- if(canque_fifo_test_and_clear_fl(&qedge->fifo, FREEONEMPTY))
- canque_edge_decref(qedge);
- break;
- case CANQUEUE_NOTIFY_SPACE:
- wake_up(&qends->endinfo.fileinfo.writeq);
- #ifdef CAN_ENABLE_KERN_FASYNC
- /* Asynchronous I/O processing */
- 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);
- #endif /*CAN_ENABLE_KERN_FASYNC*/
- break;
- case CANQUEUE_NOTIFY_NOUSR:
- wake_up(&qends->endinfo.fileinfo.readq);
- wake_up(&qends->endinfo.fileinfo.writeq);
- wake_up(&qends->endinfo.fileinfo.emptyq);
- break;
- case CANQUEUE_NOTIFY_DEAD_WANTED:
- case CANQUEUE_NOTIFY_DEAD:
- if(canque_fifo_test_and_clear_fl(&qedge->fifo, READY))
- canque_edge_decref(qedge);
- break;
- case CANQUEUE_NOTIFY_ATTACH:
- break;
- }
-}
-
-/**
- * canqueue_ends_init_kern - Linux userspace clients specific ends initialization
- * @qends: pointer to the callback side ends structure
- */
-int canqueue_ends_init_kern(struct canque_ends_t *qends)
-{
- canqueue_ends_init_gen(qends);
- qends->context=NULL;
- init_waitqueue_head(&qends->endinfo.fileinfo.readq);
- init_waitqueue_head(&qends->endinfo.fileinfo.writeq);
- init_waitqueue_head(&qends->endinfo.fileinfo.emptyq);
- #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;
-}
-
-
-/**
- * canque_get_inslot4id_wait_kern - find or wait for best outgoing edge and slot for given ID
- * @qends: ends structure belonging to calling communication object
- * @qedgep: place to store pointer to found edge
- * @slotp: place to store pointer to allocated slot
- * @cmd: command type for slot
- * @id: communication ID of message to send into edge
- * @prio: optional priority of message
- *
- * Same as canque_get_inslot4id(), except, that it waits for free slot
- * in case, that queue is full. Function is specific for Linux userspace clients.
- * Return Value: If there is no usable edge negative value is returned.
- */
-int canque_get_inslot4id_wait_kern(struct canque_ends_t *qends,
- struct canque_edge_t **qedgep, struct canque_slot_t **slotp,
- int cmd, unsigned long id, int prio)
-{
- 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),
- (ret=canque_get_inslot4id(qends,qedgep,slotp,cmd,id,prio))!=-1);
- return ret;
-}
-
-/**
- * canque_get_outslot_wait_kern - receive or wait for ready slot for given ends
- * @qends: ends structure belonging to calling communication object
- * @qedgep: place to store pointer to found edge
- * @slotp: place to store pointer to received slot
- *
- * The same as canque_test_outslot(), except it waits in the case, that there is
- * no ready slot for given ends. Function is specific for Linux userspace clients.
- * Return Value: Negative value informs, that there is no ready output
- * slot for given ends. Positive value is equal to the command
- * slot has been allocated by the input side.
- */
-int canque_get_outslot_wait_kern(struct canque_ends_t *qends,
- struct canque_edge_t **qedgep, struct canque_slot_t **slotp)
-{
- int ret=-1;
- DEBUGQUE("canque_get_outslot_wait_kern\n");
- wait_event_interruptible((qends->endinfo.fileinfo.readq),
- (ret=canque_test_outslot(qends,qedgep,slotp))!=-1);
- return ret;
-}
-
-/**
- * canque_sync_wait_kern - wait for all slots processing
- * @qends: ends structure belonging to calling communication object
- * @qedge: pointer to edge
- *
- * Functions waits for ends transition into empty state.
- * Return Value: Positive value indicates, that edge empty state has been reached.
- * Negative or zero value informs about interrupted wait or other problem.
- */
-int canque_sync_wait_kern(struct canque_ends_t *qends, struct canque_edge_t *qedge)
-{
- int ret=-1;
- DEBUGQUE("canque_sync_wait_kern\n");
- wait_event_interruptible((qends->endinfo.fileinfo.emptyq),
- (ret=canque_fifo_test_fl(&qedge->fifo,EMPTY)?1:0));
- return ret;
-}
-
-
-/**
- * canque_fifo_init_kern - initialize one CAN FIFO
- * @fifo: pointer to the FIFO structure
- * @slotsnr: number of requested slots
- *
- * Return Value: The negative value indicates, that there is no memory
- * to allocate space for the requested number of the slots.
- */
-int canque_fifo_init_kern(struct canque_fifo_t *fifo, int slotsnr)
-{
- int size;
- if(!slotsnr) slotsnr=MAX_BUF_LENGTH;
- size=sizeof(struct canque_slot_t)*slotsnr;
- fifo->entry=kmalloc(size,GFP_KERNEL);
- if(!fifo->entry) return -1;
- fifo->slotsnr=slotsnr;
- return canque_fifo_init_slots(fifo);
-}
-
-/**
- * canque_fifo_done_kern - frees slots allocated for CAN FIFO
- * @fifo: pointer to the FIFO structure
- */
-int canque_fifo_done_kern(struct canque_fifo_t *fifo)
-{
- if(fifo->entry)
- kfree(fifo->entry);
- fifo->entry=NULL;
- return 1;
-}
-
-
-/**
- * canque_new_edge_kern - allocate new edge structure in the Linux kernel context
- * @slotsnr: required number of slots in the newly allocated edge structure
- *
- * Return Value: Returns pointer to allocated slot structure or %NULL if
- * there is not enough memory to process operation.
- */
-struct canque_edge_t *canque_new_edge_kern(int slotsnr)
-{
- struct canque_edge_t *qedge;
- qedge = (struct canque_edge_t *)kmalloc(sizeof(struct canque_edge_t), GFP_KERNEL);
- if(qedge == NULL) return NULL;
-
- memset(qedge,0,sizeof(struct canque_edge_t));
- can_spin_lock_init(&qedge->fifo.fifo_lock);
- if(canque_fifo_init_kern(&qedge->fifo, slotsnr)<0){
- kfree(qedge);
- DEBUGQUE("canque_new_edge_kern failed\n");
- return NULL;
- }
- atomic_set(&qedge->edge_used,1);
- qedge->filtid = 0;
- qedge->filtmask = canque_filtid2internal(0l, (processlocal<2)? MSG_LOCAL:0);
- qedge->edge_prio = 0;
- #ifdef CAN_DEBUG
- /* not exactly clean, but enough for debugging */
- atomic_inc(&edge_num_cnt);
- qedge->edge_num=atomic_read(&edge_num_cnt);
- #endif /* CAN_DEBUG */
- DEBUGQUE("canque_new_edge_kern %d\n",qedge->edge_num);
- return qedge;
-}
-
-#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
- *
- * Same as canqueue_disconnect_edge(), but tries to wait for state with zero
- * use counter.
- * Return Value: Negative value means, that edge is used and cannot
- * be disconnected yet. Operation has to be delayed.
- */
-int canqueue_disconnect_edge_kern(struct canque_ends_t *qends, struct canque_edge_t *qedge)
-{
- canque_fifo_set_fl(&qedge->fifo,BLOCK);
- 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),
- (canqueue_disconnect_edge(qedge)>=0));
-
- /*set_current_state(TASK_UNINTERRUPTIBLE);*/
- /*schedule_timeout(HZ);*/
- return 0;
- } else {
- DEBUGQUE("canqueue_disconnect_edge_kern cannot set DEAD\n");
- return -1;
- }
-}
-
-
-int canqueue_disconnect_list_kern(struct canque_ends_t *qends, struct list_head *list)
-{
- struct canque_edge_t *edge;
- can_spin_irqflags_t flags;
- for(;;){
- can_spin_lock_irqsave(&qends->ends_lock,flags);
- if(list_empty(list)){
- can_spin_unlock_irqrestore(&qends->ends_lock,flags);
- return 0;
- }
- if(list == &qends->inlist)
- edge=list_entry(list->next,struct canque_edge_t,inpeers);
- else
- edge=list_entry(list->next,struct canque_edge_t,outpeers);
- atomic_inc(&edge->edge_used);
- can_spin_unlock_irqrestore(&qends->ends_lock,flags);
- if(canqueue_disconnect_edge_kern(qends, edge)>=0) {
- /* Free edge memory */
- canque_fifo_done_kern(&edge->fifo);
- kfree(edge);
- }else{
- canque_notify_bothends(edge, CANQUEUE_NOTIFY_DEAD_WANTED);
- canque_edge_decref(edge);
- DEBUGQUE("canqueue_disconnect_list_kern in troubles\n");
- DEBUGQUE("the edge %d has usage count %d and flags %ld\n",edge->edge_num,atomic_read(&edge->edge_used),edge->fifo.fifo_flags);
- return -1;
- }
- }
-}
-
-#endif /*USE_SYNC_DISCONNECT_EDGE_KERN*/
-
-
-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);
- }
- return 0;
-}
-
-
-void canqueue_ends_dispose_postpone(struct canque_ends_t *qends)
-{
- can_spin_irqflags_t flags;
-
- can_spin_lock_irqsave(&canque_dead_func_lock, flags);
- qends->ends_flags |= CAN_ENDSF_DEAD;
- list_add(&qends->dead_peers,&canque_dead_ends);
- can_spin_unlock_irqrestore(&canque_dead_func_lock, flags);
- canque_dead_tasklet_schedule();
-}
-
-
-/**
- * canqueue_ends_dispose_kern - finalizing of the ends structure for Linux kernel clients
- * @qends: pointer to ends structure
- * @sync: flag indicating, that user wants to wait for processing of all remaining
- * messages
- *
- * Return Value: Function should be designed such way to not fail.
- */
-int canqueue_ends_dispose_kern(struct canque_ends_t *qends, int sync)
-{
- int delayed;
-
- DEBUGQUE("canqueue_ends_dispose_kern\n");
- canqueue_block_inlist(qends);
- canqueue_block_outlist(qends);
-
- /*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 */
- delayed|=canqueue_ends_kill_outlist(qends);
-
- wake_up(&qends->endinfo.fileinfo.readq);
- wake_up(&qends->endinfo.fileinfo.writeq);
- wake_up(&qends->endinfo.fileinfo.emptyq);
-
- if(delayed){
- canqueue_ends_dispose_postpone(qends);
-
- DEBUGQUE("canqueue_ends_dispose_kern delayed\n");
- return 1;
- }
-
- kfree(qends);
- DEBUGQUE("canqueue_ends_dispose_kern finished\n");
- return 0;
-}
-
-void canqueue_kern_initialize()
-{
- can_spin_lock_init(&canque_dead_func_lock);
-}
projects / lincan.git / commitdiff