pv.rar_open_pv

#include<linux/kernel.h> #include<linux/module.h> #include<linux/sched.h> #include<linux/proc_fs.h> #include<linux/slab.h> /*#include<asm/uaccess.h>*/ #include<linux/wait.h> #include<linux/signal.h> typedef struct __myevent{ int eventNum; wait_queue_head_t *p; struct __myevent *next; }myevent_t; myevent_t *lpmyevent_head = NULL; myevent_t *lpmyevent_end = NULL; /*global variety*/ asmlinkage int sys_eventopen(int eventNum) { myevent_t *new; myevent_t *prev; if(eventNum) if(!scheventNum(eventNum,&prev)) return -1; else return eventNum; else{ new=(myevent_t *)kmalloc(sizeof(myevent_t),GFP_KERNEL); new->p = (wait_queue_head_t *)kmalloc(sizeof(wait_queue_head_t),GFP_KERNEL); new->next = NULL; new->p->task_list.next = &new->p->task_list; new->p->task_list.prev = &new->p->task_list; if (!lpmyevent_head){ new->eventNum=2; lpmyevent_head = lpmyevent_end = new; return new -> eventNum; } else { new->eventNum = lpmyevent_end->eventNum+2; lpmyevent_end->next = new; lpmyevent_end = new; } return new->eventNum; } return 0; } asmlinkage int sys_eventwait(int eventNum) { myevent_t *tmp; myevent_t *prev = NULL; wait_queue_t wait; unsigned long flags; if (tmp= scheventNum(eventNum,&prev)) { wait.task=current; current->state = TASK_UNINTERRUPTIBLE; write_lock_irqsave(&tmp->p->lock,flags); __add_wait_queue(tmp->p,&wait); write_unlock(&tmp->p->lock); schedule(); write_lock_irq(&tmp->p->lock); __remove_wait_queue(tmp->p,&wait); write_unlock_irqrestore(&tmp->p->lock,flags); } return 0; } asmlinkage int sys_eventsig(int eventNum) { myevent_t *tmp = NULL; myevent_t *prev=NULL; if(!(tmp = scheventNum(eventNum,&prev))) return 0; wake_up(tmp->p); return 1; } asmlinkage int sys_eventclose(int eventNum) { myevent_t *prev; myevent_t *releaseItem; sys_eventsig(eventNum); if(releaseItem=scheventNum(eventNum,&prev)) { if(releaseItem==lpmyevent_end) lpmyevent_end = prev; if (releaseItem == lpmyevent_head) {lpmyevent_head = lpmyevent_head->next; goto wake;} prev->next = releaseItem->next; } wake: if(releaseItem) {kfree(releaseItem); return 1;} return 0; } myevent_t * scheventNum(int eventNum,myevent_t **prev) { myevent_t *tmp = lpmyevent_head; *prev=NULL; while(tmp){ if(tmp->eventNum == eventNum) return tmp; *prev = tmp; tmp = tmp->next; } return NULL; }