WebSVN – HelenOS-historic – Diff – /kernel/trunk/generic/src/mm/as.c



    btree_t pagemap;    /**< B+tree containing complete map of anonymous pages of the shared area. */
};
 
as_operations_t *as_operations = NULL;
 
/** This lock protects inactive_as_with_asid_head list. It must be acquired before as_t mutex. */
SPINLOCK_INITIALIZE(inactive_as_with_asid_lock);
 
/**
 * This list contains address spaces that are not active on any
 * processor and that have valid ASID.
 */

    if (flags & FLAG_AS_KERNEL)
        as->asid = ASID_KERNEL;
    else
        as->asid = ASID_INVALID;
   
    as->cpu_refcount = 0;
    as->page_table = page_table_create(flags);
 
    return as;
}
 
/** Free Adress space */
void as_free(as_t *as)
{
    ASSERT(as->cpu_refcount == 0);
 
    /* TODO: free as_areas and other resources held by as */
    /* TODO: free page table */
    free(as);
}

}
 
/** Switch address spaces.
 *
 * Note that this function cannot sleep as it is essentially a part of
 * scheduling. Sleeping here would lead to deadlock on wakeup.
 *
 * @param old Old address space or NULL.
 * @param new New address space.
 */
void as_switch(as_t *old, as_t *new)
{
    ipl_t ipl;
    bool needs_asid = false;
   
    ipl = interrupts_disable();
    spinlock_lock(&inactive_as_with_asid_lock);
 
    /*
     * First, take care of the old address space.
     */
    if (old) {
        mutex_lock_active(&old->lock);
        ASSERT(old->cpu_refcount);
        if((--old->cpu_refcount == 0) && (old != AS_KERNEL)) {
            /*
             * The old address space is no longer active on
             * any processor. It can be appended to the
             * list of inactive address spaces with assigned
             * ASID.

 
    /*
     * Second, prepare the new address space.
     */
    mutex_lock_active(&new->lock);
    if ((new->cpu_refcount++ == 0) && (new != AS_KERNEL)) {
        if (new->asid != ASID_INVALID)
            list_remove(&new->inactive_as_with_asid_link);
        else
            needs_asid = true;  /* defer call to asid_get() until new->lock is released */
    }

        asid = asid_get();
        mutex_lock_active(&new->lock);
        new->asid = asid;
        mutex_unlock(&new->lock);
    }
    spinlock_unlock(&inactive_as_with_asid_lock);
    interrupts_restore(ipl);
   
    /*
     * Perform architecture-specific steps.
     * (e.g. write ASID to hardware register etc.)

Rev 1413	Rev 1415
Line 81...	Line 81...
81	btree_t pagemap; /*< B+tree containing complete map of anonymous pages of the shared area. /	81	btree_t pagemap; /*< B+tree containing complete map of anonymous pages of the shared area. /
82	};	82	};
83		83
84	as_operations_t *as_operations = NULL;	84	as_operations_t *as_operations = NULL;
85		85
86	/** Address space lock. It protects inactive_as_with_asid_head. Must be acquired before as_t mutex. */	86	/** This lock protects inactive_as_with_asid_head list. It must be acquired before as_t mutex. */
87	SPINLOCK_INITIALIZE(as_lock);	87	SPINLOCK_INITIALIZE(inactive_as_with_asid_lock);
88		88
89	/**	89	/**
90	* This list contains address spaces that are not active on any	90	* This list contains address spaces that are not active on any
91	* processor and that have valid ASID.	91	* processor and that have valid ASID.
92	*/	92	*/
Line 126...	Line 126...
126	if (flags & FLAG_AS_KERNEL)	126	if (flags & FLAG_AS_KERNEL)
127	as->asid = ASID_KERNEL;	127	as->asid = ASID_KERNEL;
128	else	128	else
129	as->asid = ASID_INVALID;	129	as->asid = ASID_INVALID;
130		130
131	as->refcount = 0;	131	as->cpu_refcount = 0;
132	as->page_table = page_table_create(flags);	132	as->page_table = page_table_create(flags);
133		133
134	return as;	134	return as;
135	}	135	}
136		136
137	/** Free Adress space */	137	/** Free Adress space */
138	void as_free(as_t *as)	138	void as_free(as_t *as)
139	{	139	{
140	ASSERT(as->refcount == 0);	140	ASSERT(as->cpu_refcount == 0);
141		141
142	/* TODO: free as_areas and other resources held by as */	142	/* TODO: free as_areas and other resources held by as */
143	/* TODO: free page table */	143	/* TODO: free page table */
144	free(as);	144	free(as);
145	}	145	}
Line 731...	Line 731...
731	}	731	}
732		732
733	/** Switch address spaces.	733	/** Switch address spaces.
734	*	734	*
735	* Note that this function cannot sleep as it is essentially a part of	735	* Note that this function cannot sleep as it is essentially a part of
736	* the scheduling. Sleeping here would lead to deadlock on wakeup.	736	* scheduling. Sleeping here would lead to deadlock on wakeup.
737	*	737	*
738	* @param old Old address space or NULL.	738	* @param old Old address space or NULL.
739	* @param new New address space.	739	* @param new New address space.
740	*/	740	*/
741	void as_switch(as_t old, as_t new)	741	void as_switch(as_t old, as_t new)
742	{	742	{
743	ipl_t ipl;	743	ipl_t ipl;
744	bool needs_asid = false;	744	bool needs_asid = false;
745		745
746	ipl = interrupts_disable();	746	ipl = interrupts_disable();
747	spinlock_lock(&as_lock);	747	spinlock_lock(&inactive_as_with_asid_lock);
748		748
749	/*	749	/*
750	* First, take care of the old address space.	750	* First, take care of the old address space.
751	*/	751	*/
752	if (old) {	752	if (old) {
753	mutex_lock_active(&old->lock);	753	mutex_lock_active(&old->lock);
754	ASSERT(old->refcount);	754	ASSERT(old->cpu_refcount);
755	if((--old->refcount == 0) && (old != AS_KERNEL)) {	755	if((--old->cpu_refcount == 0) && (old != AS_KERNEL)) {
756	/*	756	/*
757	* The old address space is no longer active on	757	* The old address space is no longer active on
758	* any processor. It can be appended to the	758	* any processor. It can be appended to the
759	* list of inactive address spaces with assigned	759	* list of inactive address spaces with assigned
760	* ASID.	760	* ASID.
Line 767...	Line 767...
767		767
768	/*	768	/*
769	* Second, prepare the new address space.	769	* Second, prepare the new address space.
770	*/	770	*/
771	mutex_lock_active(&new->lock);	771	mutex_lock_active(&new->lock);
772	if ((new->refcount++ == 0) && (new != AS_KERNEL)) {	772	if ((new->cpu_refcount++ == 0) && (new != AS_KERNEL)) {
773	if (new->asid != ASID_INVALID)	773	if (new->asid != ASID_INVALID)
774	list_remove(&new->inactive_as_with_asid_link);	774	list_remove(&new->inactive_as_with_asid_link);
775	else	775	else
776	needs_asid = true; /* defer call to asid_get() until new->lock is released */	776	needs_asid = true; /* defer call to asid_get() until new->lock is released */
777	}	777	}
Line 788...	Line 788...
788	asid = asid_get();	788	asid = asid_get();
789	mutex_lock_active(&new->lock);	789	mutex_lock_active(&new->lock);
790	new->asid = asid;	790	new->asid = asid;
791	mutex_unlock(&new->lock);	791	mutex_unlock(&new->lock);
792	}	792	}
793	spinlock_unlock(&as_lock);	793	spinlock_unlock(&inactive_as_with_asid_lock);
794	interrupts_restore(ipl);	794	interrupts_restore(ipl);
795		795
796	/*	796	/*
797	* Perform architecture-specific steps.	797	* Perform architecture-specific steps.
798	* (e.g. write ASID to hardware register etc.)	798	* (e.g. write ASID to hardware register etc.)

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/mm/as.c – Rev 1413 → 1415