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



#include <genarch/mm/page_pt.h>
#include <genarch/mm/page_ht.h>
#include <mm/asid.h>
#include <arch/mm/asid.h>
#include <synch/spinlock.h>
#include <synch/mutex.h>
#include <adt/list.h>
#include <adt/btree.h>
#include <proc/task.h>
#include <proc/thread.h>
#include <arch/asm.h>

#include <syscall/copy.h>
#include <arch/interrupt.h>
 
as_operations_t *as_operations = NULL;
 
/** Address space lock. It protects inactive_as_with_asid_head. Must be acquired before as_t mutex. */
SPINLOCK_INITIALIZE(as_lock);
 
/**
 * This list contains address spaces that are not active on any
 * processor and that have valid ASID.

{
    as_t *as;
 
    as = (as_t *) malloc(sizeof(as_t), 0);
    link_initialize(&as->inactive_as_with_asid_link);
    mutex_initialize(&as->lock);
    btree_create(&as->as_area_btree);
   
    if (flags & FLAG_AS_KERNEL)
        as->asid = ASID_KERNEL;
    else

    /* Writeable executable areas are not supported. */
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
        return NULL;
   
    ipl = interrupts_disable();
    mutex_lock(&as->lock);
   
    if (!check_area_conflicts(as, base, size, NULL)) {
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return NULL;
    }
   
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
 
    mutex_initialize(&a->lock);
   
    a->flags = flags;
    a->attributes = attrs;
    a->pages = SIZE2FRAMES(size);
    a->base = base;
   
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
 
    mutex_unlock(&as->lock);
    interrupts_restore(ipl);
 
    return a;
}
 

    as_area_t *area;
    ipl_t ipl;
    size_t pages;
   
    ipl = interrupts_disable();
    mutex_lock(&as->lock);
   
    /*
     * Locate the area.
     */
    area = find_area_and_lock(as, address);
    if (!area) {
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return ENOENT;
    }
 
    if (area->flags & AS_AREA_DEVICE) {
        /*
         * Remapping of address space areas associated
         * with memory mapped devices is not supported.
         */
        mutex_unlock(&area->lock);
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return ENOTSUP;
    }
 
    pages = SIZE2FRAMES((address - area->base) + size);
    if (!pages) {
        /*
         * Zero size address space areas are not allowed.
         */
        mutex_unlock(&area->lock);
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return EPERM;
    }
   
    if (pages < area->pages) {

        /*
         * Growing the area.
         * Check for overlaps with other address space areas.
         */
        if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) {
            mutex_unlock(&area->lock);
            mutex_unlock(&as->lock);       
            interrupts_restore(ipl);
            return EADDRNOTAVAIL;
        }
    }
 
    area->pages = pages;
   
    mutex_unlock(&area->lock);
    mutex_unlock(&as->lock);
    interrupts_restore(ipl);
 
    return 0;
}
 

    __address base;
    ipl_t ipl;
    int i;
 
    ipl = interrupts_disable();
    mutex_lock(&as->lock);
 
    area = find_area_and_lock(as, address);
    if (!area) {
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return ENOENT;
    }
 
    base = area->base; 

    tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base, area->pages);
    tlb_invalidate_pages(AS->asid, area->base, area->pages);
    tlb_shootdown_finalize();
 
    area->attributes |= AS_AREA_ATTR_PARTIAL;
    mutex_unlock(&area->lock);
 
    /*
     * Remove the empty area from address space.
     */
    btree_remove(&AS->as_area_btree, base, NULL);
   
    free(area);
   
    mutex_unlock(&AS->lock);
    interrupts_restore(ipl);
    return 0;
}
 
/** Steal address space area from another task.

 
    ipl = interrupts_disable();
    spinlock_lock(&src_task->lock);
    src_as = src_task->as;
   
    mutex_lock(&src_as->lock);
    src_area = find_area_and_lock(src_as, src_base);
    if (!src_area) {
        /*
         * Could not find the source address space area.
         */
        spinlock_unlock(&src_task->lock);
        mutex_unlock(&src_as->lock);
        interrupts_restore(ipl);
        return ENOENT;
    }
    src_size = src_area->pages * PAGE_SIZE;
    src_flags = src_area->flags;
    mutex_unlock(&src_area->lock);
    mutex_unlock(&src_as->lock);
 
 
    if (src_size != acc_size) {
        spinlock_unlock(&src_task->lock);
        interrupts_restore(ipl);

   
    /*
     * Avoid deadlock by first locking the address space with lower address.
     */
    if (AS < src_as) {
        mutex_lock(&AS->lock);
        mutex_lock(&src_as->lock);
    } else {
        mutex_lock(&AS->lock);
        mutex_lock(&src_as->lock);
    }
   
    for (i = 0; i < SIZE2FRAMES(src_size); i++) {
        pte_t *pte;
        __address frame;

    /*
     * Now the destination address space area has been
     * fully initialized. Clear the AS_AREA_ATTR_PARTIAL
     * attribute.
     */
    mutex_lock(&dst_area->lock);
    dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
    mutex_unlock(&dst_area->lock);
   
    mutex_unlock(&AS->lock);
    mutex_unlock(&src_as->lock);
    interrupts_restore(ipl);
   
    return 0;
}
 

        panic("page not part of any as_area\n");
    }
 
    page_mapping_insert(as, page, frame, get_area_flags(area));
   
    mutex_unlock(&area->lock);
    page_table_unlock(as, true);
    interrupts_restore(ipl);
}
 
/** Handle page fault within the current address space.

{
    pte_t *pte;
    as_area_t *area;
    __address frame;
   
    if (!THREAD)
        return 0;
       
    ASSERT(AS);
 
    mutex_lock(&AS->lock);
    area = find_area_and_lock(AS, page);   
    if (!area) {
        /*
         * No area contained mapping for 'page'.
         * Signal page fault to low-level handler.
         */
        mutex_unlock(&AS->lock);
        goto page_fault;
    }
 
    if (area->attributes & AS_AREA_ATTR_PARTIAL) {
        /*
         * The address space area is not fully initialized.
         * Avoid possible race by returning error.
         */
        mutex_unlock(&area->lock);
        mutex_unlock(&AS->lock);
        goto page_fault;       
    }
 
    ASSERT(!(area->flags & AS_AREA_DEVICE));
 

     * the mapping has not been already inserted.
     */
    if ((pte = page_mapping_find(AS, page))) {
        if (PTE_PRESENT(pte)) {
            page_table_unlock(AS, false);
            mutex_unlock(&area->lock);
            mutex_unlock(&AS->lock);
            return 1;
        }
    }
 
    /*

     * inserted into page tables.
     */
    page_mapping_insert(AS, page, frame, get_area_flags(area));
    page_table_unlock(AS, false);
   
    mutex_unlock(&area->lock);
    mutex_unlock(&AS->lock);
    return AS_PF_OK;
 
page_fault:
    if (!THREAD)
        return AS_PF_FAULT;

    return AS_PF_DEFER;
}
 
/** Switch address spaces.
 *
 * Note that this function cannot sleep as it is essentially a part of
 * the 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)
{

 
    /*
     * First, take care of the old address space.
     */
    if (old) {
        mutex_lock_active(&old->lock);
        ASSERT(old->refcount);
        if((--old->refcount == 0) && (old != AS_KERNEL)) {
            /*
             * The old address space is no longer active on
             * any processor. It can be appended to the

             * ASID.
             */
             ASSERT(old->asid != ASID_INVALID);
             list_append(&old->inactive_as_with_asid_link, &inactive_as_with_asid_head);
        }
        mutex_unlock(&old->lock);
    }
 
    /*
     * Second, prepare the new address space.
     */
    mutex_lock_active(&new->lock);
    if ((new->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 */
    }
    SET_PTL0_ADDRESS(new->page_table);
    mutex_unlock(&new->lock);
 
    if (needs_asid) {
        /*
         * Allocation of new ASID was deferred
         * until now in order to avoid deadlock.
         */
        asid_t asid;
       
        asid = asid_get();
        mutex_lock_active(&new->lock);
        new->asid = asid;
        mutex_unlock(&new->lock);
    }
    spinlock_unlock(&as_lock);
    interrupts_restore(ipl);
   
    /*

    int i;
   
    a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
    if (a) {
        /* va is the base address of an address space area */
        mutex_lock(&a->lock);
        return a;
    }
   
    /*
     * Search the leaf node and the righmost record of its left neighbour

     */
   
    /* First, search the leaf node itself. */
    for (i = 0; i < leaf->keys; i++) {
        a = (as_area_t *) leaf->value[i];
        mutex_lock(&a->lock);
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
            return a;
        }
        mutex_unlock(&a->lock);
    }
 
    /*
     * Second, locate the left neighbour and test its last record.
     * Because of its position in the B+tree, it must have base < va.
     */
    if ((lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
        a = (as_area_t *) lnode->value[lnode->keys - 1];
        mutex_lock(&a->lock);
        if (va < a->base + a->pages * PAGE_SIZE) {
            return a;
        }
        mutex_unlock(&a->lock);
    }
 
    return NULL;
}
 

    }
   
    /* First, check the two border cases. */
    if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
        a = (as_area_t *) node->value[node->keys - 1];
        mutex_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            mutex_unlock(&a->lock);
            return false;
        }
        mutex_unlock(&a->lock);
    }
    if ((node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf))) {
        a = (as_area_t *) node->value[0];
        mutex_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            mutex_unlock(&a->lock);
            return false;
        }
        mutex_unlock(&a->lock);
    }
   
    /* Second, check the leaf node. */
    for (i = 0; i < leaf->keys; i++) {
        a = (as_area_t *) leaf->value[i];
   
        if (a == avoid_area)
            continue;
   
        mutex_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            mutex_unlock(&a->lock);
            return false;
        }
        mutex_unlock(&a->lock);
    }
 
    /*
     * So far, the area does not conflict with other areas.
     * Check if it doesn't conflict with kernel address space.

    }
 
    return true;
}
 
/** Return size of the address space area with given base.  */
size_t as_get_size(__address base)
{
    ipl_t ipl;
    as_area_t *src_area;
    size_t size;
 
    ipl = interrupts_disable();
    src_area = find_area_and_lock(AS, base);
    if (src_area){
        size = src_area->pages * PAGE_SIZE;
        mutex_unlock(&src_area->lock);
    } else {
        size = 0;
    }
    interrupts_restore(ipl);
    return size;

Rev 1358	Rev 1380
Line 52...	Line 52...
52	#include <genarch/mm/page_pt.h>	52	#include <genarch/mm/page_pt.h>
53	#include <genarch/mm/page_ht.h>	53	#include <genarch/mm/page_ht.h>
54	#include <mm/asid.h>	54	#include <mm/asid.h>
55	#include <arch/mm/asid.h>	55	#include <arch/mm/asid.h>
56	#include <synch/spinlock.h>	56	#include <synch/spinlock.h>
-		57	#include <synch/mutex.h>
57	#include <adt/list.h>	58	#include <adt/list.h>
58	#include <adt/btree.h>	59	#include <adt/btree.h>
59	#include <proc/task.h>	60	#include <proc/task.h>
60	#include <proc/thread.h>	61	#include <proc/thread.h>
61	#include <arch/asm.h>	62	#include <arch/asm.h>
Line 72...	Line 73...
72	#include <syscall/copy.h>	73	#include <syscall/copy.h>
73	#include <arch/interrupt.h>	74	#include <arch/interrupt.h>
74		75
75	as_operations_t *as_operations = NULL;	76	as_operations_t *as_operations = NULL;
76		77
77	/** Address space lock. It protects inactive_as_with_asid_head. */	78	/** Address space lock. It protects inactive_as_with_asid_head. Must be acquired before as_t mutex. */
78	SPINLOCK_INITIALIZE(as_lock);	79	SPINLOCK_INITIALIZE(as_lock);
79		80
80	/**	81	/**
81	* This list contains address spaces that are not active on any	82	* This list contains address spaces that are not active on any
82	* processor and that have valid ASID.	83	* processor and that have valid ASID.
Line 108...	Line 109...
108	{	109	{
109	as_t *as;	110	as_t *as;
110		111
111	as = (as_t *) malloc(sizeof(as_t), 0);	112	as = (as_t *) malloc(sizeof(as_t), 0);
112	link_initialize(&as->inactive_as_with_asid_link);	113	link_initialize(&as->inactive_as_with_asid_link);
113	spinlock_initialize(&as->lock, "as_lock");	114	mutex_initialize(&as->lock);
114	btree_create(&as->as_area_btree);	115	btree_create(&as->as_area_btree);
115		116
116	if (flags & FLAG_AS_KERNEL)	117	if (flags & FLAG_AS_KERNEL)
117	as->asid = ASID_KERNEL;	118	as->asid = ASID_KERNEL;
118	else	119	else
Line 160...	Line 161...
160	/* Writeable executable areas are not supported. */	161	/* Writeable executable areas are not supported. */
161	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))	162	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
162	return NULL;	163	return NULL;
163		164
164	ipl = interrupts_disable();	165	ipl = interrupts_disable();
165	spinlock_lock(&as->lock);	166	mutex_lock(&as->lock);
166		167
167	if (!check_area_conflicts(as, base, size, NULL)) {	168	if (!check_area_conflicts(as, base, size, NULL)) {
168	spinlock_unlock(&as->lock);	169	mutex_unlock(&as->lock);
169	interrupts_restore(ipl);	170	interrupts_restore(ipl);
170	return NULL;	171	return NULL;
171	}	172	}
172		173
173	a = (as_area_t *) malloc(sizeof(as_area_t), 0);	174	a = (as_area_t *) malloc(sizeof(as_area_t), 0);
174		175
175	spinlock_initialize(&a->lock, "as_area_lock");	176	mutex_initialize(&a->lock);
176		177
177	a->flags = flags;	178	a->flags = flags;
178	a->attributes = attrs;	179	a->attributes = attrs;
179	a->pages = SIZE2FRAMES(size);	180	a->pages = SIZE2FRAMES(size);
180	a->base = base;	181	a->base = base;
181		182
182	btree_insert(&as->as_area_btree, base, (void *) a, NULL);	183	btree_insert(&as->as_area_btree, base, (void *) a, NULL);
183		184
184	spinlock_unlock(&as->lock);	185	mutex_unlock(&as->lock);
185	interrupts_restore(ipl);	186	interrupts_restore(ipl);
186		187
187	return a;	188	return a;
188	}	189	}
189		190
Line 201...	Line 202...
201	as_area_t *area;	202	as_area_t *area;
202	ipl_t ipl;	203	ipl_t ipl;
203	size_t pages;	204	size_t pages;
204		205
205	ipl = interrupts_disable();	206	ipl = interrupts_disable();
206	spinlock_lock(&as->lock);	207	mutex_lock(&as->lock);
207		208
208	/*	209	/*
209	* Locate the area.	210	* Locate the area.
210	*/	211	*/
211	area = find_area_and_lock(as, address);	212	area = find_area_and_lock(as, address);
212	if (!area) {	213	if (!area) {
213	spinlock_unlock(&as->lock);	214	mutex_unlock(&as->lock);
214	interrupts_restore(ipl);	215	interrupts_restore(ipl);
215	return ENOENT;	216	return ENOENT;
216	}	217	}
217		218
218	if (area->flags & AS_AREA_DEVICE) {	219	if (area->flags & AS_AREA_DEVICE) {
219	/*	220	/*
220	* Remapping of address space areas associated	221	* Remapping of address space areas associated
221	* with memory mapped devices is not supported.	222	* with memory mapped devices is not supported.
222	*/	223	*/
223	spinlock_unlock(&area->lock);	224	mutex_unlock(&area->lock);
224	spinlock_unlock(&as->lock);	225	mutex_unlock(&as->lock);
225	interrupts_restore(ipl);	226	interrupts_restore(ipl);
226	return ENOTSUP;	227	return ENOTSUP;
227	}	228	}
228		229
229	pages = SIZE2FRAMES((address - area->base) + size);	230	pages = SIZE2FRAMES((address - area->base) + size);
230	if (!pages) {	231	if (!pages) {
231	/*	232	/*
232	* Zero size address space areas are not allowed.	233	* Zero size address space areas are not allowed.
233	*/	234	*/
234	spinlock_unlock(&area->lock);	235	mutex_unlock(&area->lock);
235	spinlock_unlock(&as->lock);	236	mutex_unlock(&as->lock);
236	interrupts_restore(ipl);	237	interrupts_restore(ipl);
237	return EPERM;	238	return EPERM;
238	}	239	}
239		240
240	if (pages < area->pages) {	241	if (pages < area->pages) {
Line 276...	Line 277...
276	/*	277	/*
277	* Growing the area.	278	* Growing the area.
278	* Check for overlaps with other address space areas.	279	* Check for overlaps with other address space areas.
279	*/	280	*/
280	if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) {	281	if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) {
281	spinlock_unlock(&area->lock);	282	mutex_unlock(&area->lock);
282	spinlock_unlock(&as->lock);	283	mutex_unlock(&as->lock);
283	interrupts_restore(ipl);	284	interrupts_restore(ipl);
284	return EADDRNOTAVAIL;	285	return EADDRNOTAVAIL;
285	}	286	}
286	}	287	}
287		288
288	area->pages = pages;	289	area->pages = pages;
289		290
290	spinlock_unlock(&area->lock);	291	mutex_unlock(&area->lock);
291	spinlock_unlock(&as->lock);	292	mutex_unlock(&as->lock);
292	interrupts_restore(ipl);	293	interrupts_restore(ipl);
293		294
294	return 0;	295	return 0;
295	}	296	}
296		297
Line 307...	Line 308...
307	__address base;	308	__address base;
308	ipl_t ipl;	309	ipl_t ipl;
309	int i;	310	int i;
310		311
311	ipl = interrupts_disable();	312	ipl = interrupts_disable();
312	spinlock_lock(&as->lock);	313	mutex_lock(&as->lock);
313		314
314	area = find_area_and_lock(as, address);	315	area = find_area_and_lock(as, address);
315	if (!area) {	316	if (!area) {
316	spinlock_unlock(&as->lock);	317	mutex_unlock(&as->lock);
317	interrupts_restore(ipl);	318	interrupts_restore(ipl);
318	return ENOENT;	319	return ENOENT;
319	}	320	}
320		321
321	base = area->base;	322	base = area->base;
Line 348...	Line 349...
348	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base, area->pages);	349	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base, area->pages);
349	tlb_invalidate_pages(AS->asid, area->base, area->pages);	350	tlb_invalidate_pages(AS->asid, area->base, area->pages);
350	tlb_shootdown_finalize();	351	tlb_shootdown_finalize();
351		352
352	area->attributes \|= AS_AREA_ATTR_PARTIAL;	353	area->attributes \|= AS_AREA_ATTR_PARTIAL;
353	spinlock_unlock(&area->lock);	354	mutex_unlock(&area->lock);
354		355
355	/*	356	/*
356	* Remove the empty area from address space.	357	* Remove the empty area from address space.
357	*/	358	*/
358	btree_remove(&AS->as_area_btree, base, NULL);	359	btree_remove(&AS->as_area_btree, base, NULL);
359		360
360	free(area);	361	free(area);
361		362
362	spinlock_unlock(&AS->lock);	363	mutex_unlock(&AS->lock);
363	interrupts_restore(ipl);	364	interrupts_restore(ipl);
364	return 0;	365	return 0;
365	}	366	}
366		367
367	/** Steal address space area from another task.	368	/** Steal address space area from another task.
Line 395...	Line 396...
395		396
396	ipl = interrupts_disable();	397	ipl = interrupts_disable();
397	spinlock_lock(&src_task->lock);	398	spinlock_lock(&src_task->lock);
398	src_as = src_task->as;	399	src_as = src_task->as;
399		400
400	spinlock_lock(&src_as->lock);	401	mutex_lock(&src_as->lock);
401	src_area = find_area_and_lock(src_as, src_base);	402	src_area = find_area_and_lock(src_as, src_base);
402	if (!src_area) {	403	if (!src_area) {
403	/*	404	/*
404	* Could not find the source address space area.	405	* Could not find the source address space area.
405	*/	406	*/
406	spinlock_unlock(&src_task->lock);	407	spinlock_unlock(&src_task->lock);
407	spinlock_unlock(&src_as->lock);	408	mutex_unlock(&src_as->lock);
408	interrupts_restore(ipl);	409	interrupts_restore(ipl);
409	return ENOENT;	410	return ENOENT;
410	}	411	}
411	src_size = src_area->pages * PAGE_SIZE;	412	src_size = src_area->pages * PAGE_SIZE;
412	src_flags = src_area->flags;	413	src_flags = src_area->flags;
413	spinlock_unlock(&src_area->lock);	414	mutex_unlock(&src_area->lock);
414	spinlock_unlock(&src_as->lock);	415	mutex_unlock(&src_as->lock);
415		416
416		417
417	if (src_size != acc_size) {	418	if (src_size != acc_size) {
418	spinlock_unlock(&src_task->lock);	419	spinlock_unlock(&src_task->lock);
419	interrupts_restore(ipl);	420	interrupts_restore(ipl);
Line 439...	Line 440...
439		440
440	/*	441	/*
441	* Avoid deadlock by first locking the address space with lower address.	442	* Avoid deadlock by first locking the address space with lower address.
442	*/	443	*/
443	if (AS < src_as) {	444	if (AS < src_as) {
444	spinlock_lock(&AS->lock);	445	mutex_lock(&AS->lock);
445	spinlock_lock(&src_as->lock);	446	mutex_lock(&src_as->lock);
446	} else {	447	} else {
447	spinlock_lock(&AS->lock);	448	mutex_lock(&AS->lock);
448	spinlock_lock(&src_as->lock);	449	mutex_lock(&src_as->lock);
449	}	450	}
450		451
451	for (i = 0; i < SIZE2FRAMES(src_size); i++) {	452	for (i = 0; i < SIZE2FRAMES(src_size); i++) {
452	pte_t *pte;	453	pte_t *pte;
453	__address frame;	454	__address frame;
Line 473...	Line 474...
473	/*	474	/*
474	* Now the destination address space area has been	475	* Now the destination address space area has been
475	* fully initialized. Clear the AS_AREA_ATTR_PARTIAL	476	* fully initialized. Clear the AS_AREA_ATTR_PARTIAL
476	* attribute.	477	* attribute.
477	*/	478	*/
478	spinlock_lock(&dst_area->lock);	479	mutex_lock(&dst_area->lock);
479	dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;	480	dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
480	spinlock_unlock(&dst_area->lock);	481	mutex_unlock(&dst_area->lock);
481		482
482	spinlock_unlock(&AS->lock);	483	mutex_unlock(&AS->lock);
483	spinlock_unlock(&src_as->lock);	484	mutex_unlock(&src_as->lock);
484	interrupts_restore(ipl);	485	interrupts_restore(ipl);
485		486
486	return 0;	487	return 0;
487	}	488	}
488		489
Line 509...	Line 510...
509	panic("page not part of any as_area\n");	510	panic("page not part of any as_area\n");
510	}	511	}
511		512
512	page_mapping_insert(as, page, frame, get_area_flags(area));	513	page_mapping_insert(as, page, frame, get_area_flags(area));
513		514
514	spinlock_unlock(&area->lock);	515	mutex_unlock(&area->lock);
515	page_table_unlock(as, true);	516	page_table_unlock(as, true);
516	interrupts_restore(ipl);	517	interrupts_restore(ipl);
517	}	518	}
518		519
519	/** Handle page fault within the current address space.	520	/** Handle page fault within the current address space.
Line 530...	Line 531...
530	{	531	{
531	pte_t *pte;	532	pte_t *pte;
532	as_area_t *area;	533	as_area_t *area;
533	__address frame;	534	__address frame;
534		535
-		536	if (!THREAD)
-		537	return 0;
-		538
535	ASSERT(AS);	539	ASSERT(AS);
536		540
537	spinlock_lock(&AS->lock);	541	mutex_lock(&AS->lock);
538	area = find_area_and_lock(AS, page);	542	area = find_area_and_lock(AS, page);
539	if (!area) {	543	if (!area) {
540	/*	544	/*
541	* No area contained mapping for 'page'.	545	* No area contained mapping for 'page'.
542	* Signal page fault to low-level handler.	546	* Signal page fault to low-level handler.
543	*/	547	*/
544	spinlock_unlock(&AS->lock);	548	mutex_unlock(&AS->lock);
545	goto page_fault;	549	goto page_fault;
546	}	550	}
547		551
548	if (area->attributes & AS_AREA_ATTR_PARTIAL) {	552	if (area->attributes & AS_AREA_ATTR_PARTIAL) {
549	/*	553	/*
550	* The address space area is not fully initialized.	554	* The address space area is not fully initialized.
551	* Avoid possible race by returning error.	555	* Avoid possible race by returning error.
552	*/	556	*/
553	spinlock_unlock(&area->lock);	557	mutex_unlock(&area->lock);
554	spinlock_unlock(&AS->lock);	558	mutex_unlock(&AS->lock);
555	goto page_fault;	559	goto page_fault;
556	}	560	}
557		561
558	ASSERT(!(area->flags & AS_AREA_DEVICE));	562	ASSERT(!(area->flags & AS_AREA_DEVICE));
559		563
Line 565...	Line 569...
565	* the mapping has not been already inserted.	569	* the mapping has not been already inserted.
566	*/	570	*/
567	if ((pte = page_mapping_find(AS, page))) {	571	if ((pte = page_mapping_find(AS, page))) {
568	if (PTE_PRESENT(pte)) {	572	if (PTE_PRESENT(pte)) {
569	page_table_unlock(AS, false);	573	page_table_unlock(AS, false);
570	spinlock_unlock(&area->lock);	574	mutex_unlock(&area->lock);
571	spinlock_unlock(&AS->lock);	575	mutex_unlock(&AS->lock);
572	return 1;	576	return 1;
573	}	577	}
574	}	578	}
575		579
576	/*	580	/*
Line 596...	Line 600...
596	* inserted into page tables.	600	* inserted into page tables.
597	*/	601	*/
598	page_mapping_insert(AS, page, frame, get_area_flags(area));	602	page_mapping_insert(AS, page, frame, get_area_flags(area));
599	page_table_unlock(AS, false);	603	page_table_unlock(AS, false);
600		604
601	spinlock_unlock(&area->lock);	605	mutex_unlock(&area->lock);
602	spinlock_unlock(&AS->lock);	606	mutex_unlock(&AS->lock);
603	return AS_PF_OK;	607	return AS_PF_OK;
604		608
605	page_fault:	609	page_fault:
606	if (!THREAD)	610	if (!THREAD)
607	return AS_PF_FAULT;	611	return AS_PF_FAULT;
Line 619...	Line 623...
619	return AS_PF_DEFER;	623	return AS_PF_DEFER;
620	}	624	}
621		625
622	/** Switch address spaces.	626	/** Switch address spaces.
623	*	627	*
-		628	* Note that this function cannot sleep as it is essentially a part of
-		629	* the scheduling. Sleeping here would lead to deadlock on wakeup.
-		630	*
624	* @param old Old address space or NULL.	631	* @param old Old address space or NULL.
625	* @param new New address space.	632	* @param new New address space.
626	*/	633	*/
627	void as_switch(as_t old, as_t new)	634	void as_switch(as_t old, as_t new)
628	{	635	{
Line 634...	Line 641...
634		641
635	/*	642	/*
636	* First, take care of the old address space.	643	* First, take care of the old address space.
637	*/	644	*/
638	if (old) {	645	if (old) {
639	spinlock_lock(&old->lock);	646	mutex_lock_active(&old->lock);
640	ASSERT(old->refcount);	647	ASSERT(old->refcount);
641	if((--old->refcount == 0) && (old != AS_KERNEL)) {	648	if((--old->refcount == 0) && (old != AS_KERNEL)) {
642	/*	649	/*
643	* The old address space is no longer active on	650	* The old address space is no longer active on
644	* any processor. It can be appended to the	651	* any processor. It can be appended to the
Line 646...	Line 653...
646	* ASID.	653	* ASID.
647	*/	654	*/
648	ASSERT(old->asid != ASID_INVALID);	655	ASSERT(old->asid != ASID_INVALID);
649	list_append(&old->inactive_as_with_asid_link, &inactive_as_with_asid_head);	656	list_append(&old->inactive_as_with_asid_link, &inactive_as_with_asid_head);
650	}	657	}
651	spinlock_unlock(&old->lock);	658	mutex_unlock(&old->lock);
652	}	659	}
653		660
654	/*	661	/*
655	* Second, prepare the new address space.	662	* Second, prepare the new address space.
656	*/	663	*/
657	spinlock_lock(&new->lock);	664	mutex_lock_active(&new->lock);
658	if ((new->refcount++ == 0) && (new != AS_KERNEL)) {	665	if ((new->refcount++ == 0) && (new != AS_KERNEL)) {
659	if (new->asid != ASID_INVALID)	666	if (new->asid != ASID_INVALID)
660	list_remove(&new->inactive_as_with_asid_link);	667	list_remove(&new->inactive_as_with_asid_link);
661	else	668	else
662	needs_asid = true; /* defer call to asid_get() until new->lock is released */	669	needs_asid = true; /* defer call to asid_get() until new->lock is released */
663	}	670	}
664	SET_PTL0_ADDRESS(new->page_table);	671	SET_PTL0_ADDRESS(new->page_table);
665	spinlock_unlock(&new->lock);	672	mutex_unlock(&new->lock);
666		673
667	if (needs_asid) {	674	if (needs_asid) {
668	/*	675	/*
669	* Allocation of new ASID was deferred	676	* Allocation of new ASID was deferred
670	* until now in order to avoid deadlock.	677	* until now in order to avoid deadlock.
671	*/	678	*/
672	asid_t asid;	679	asid_t asid;
673		680
674	asid = asid_get();	681	asid = asid_get();
675	spinlock_lock(&new->lock);	682	mutex_lock_active(&new->lock);
676	new->asid = asid;	683	new->asid = asid;
677	spinlock_unlock(&new->lock);	684	mutex_unlock(&new->lock);
678	}	685	}
679	spinlock_unlock(&as_lock);	686	spinlock_unlock(&as_lock);
680	interrupts_restore(ipl);	687	interrupts_restore(ipl);
681		688
682	/*	689	/*
Line 796...	Line 803...
796	int i;	803	int i;
797		804
798	a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);	805	a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
799	if (a) {	806	if (a) {
800	/* va is the base address of an address space area */	807	/* va is the base address of an address space area */
801	spinlock_lock(&a->lock);	808	mutex_lock(&a->lock);
802	return a;	809	return a;
803	}	810	}
804		811
805	/*	812	/*
806	* Search the leaf node and the righmost record of its left neighbour	813	* Search the leaf node and the righmost record of its left neighbour
Line 809...	Line 816...
809	*/	816	*/
810		817
811	/* First, search the leaf node itself. */	818	/* First, search the leaf node itself. */
812	for (i = 0; i < leaf->keys; i++) {	819	for (i = 0; i < leaf->keys; i++) {
813	a = (as_area_t *) leaf->value[i];	820	a = (as_area_t *) leaf->value[i];
814	spinlock_lock(&a->lock);	821	mutex_lock(&a->lock);
815	if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {	822	if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
816	return a;	823	return a;
817	}	824	}
818	spinlock_unlock(&a->lock);	825	mutex_unlock(&a->lock);
819	}	826	}
820		827
821	/*	828	/*
822	* Second, locate the left neighbour and test its last record.	829	* Second, locate the left neighbour and test its last record.
823	* Because of its position in the B+tree, it must have base < va.	830	* Because of its position in the B+tree, it must have base < va.
824	*/	831	*/
825	if ((lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {	832	if ((lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
826	a = (as_area_t *) lnode->value[lnode->keys - 1];	833	a = (as_area_t *) lnode->value[lnode->keys - 1];
827	spinlock_lock(&a->lock);	834	mutex_lock(&a->lock);
828	if (va < a->base + a->pages * PAGE_SIZE) {	835	if (va < a->base + a->pages * PAGE_SIZE) {
829	return a;	836	return a;
830	}	837	}
831	spinlock_unlock(&a->lock);	838	mutex_unlock(&a->lock);
832	}	839	}
833		840
834	return NULL;	841	return NULL;
835	}	842	}
836		843
Line 871...	Line 878...
871	}	878	}
872		879
873	/* First, check the two border cases. */	880	/* First, check the two border cases. */
874	if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {	881	if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
875	a = (as_area_t *) node->value[node->keys - 1];	882	a = (as_area_t *) node->value[node->keys - 1];
876	spinlock_lock(&a->lock);	883	mutex_lock(&a->lock);
877	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {	884	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
878	spinlock_unlock(&a->lock);	885	mutex_unlock(&a->lock);
879	return false;	886	return false;
880	}	887	}
881	spinlock_unlock(&a->lock);	888	mutex_unlock(&a->lock);
882	}	889	}
883	if ((node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf))) {	890	if ((node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf))) {
884	a = (as_area_t *) node->value[0];	891	a = (as_area_t *) node->value[0];
885	spinlock_lock(&a->lock);	892	mutex_lock(&a->lock);
886	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {	893	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
887	spinlock_unlock(&a->lock);	894	mutex_unlock(&a->lock);
888	return false;	895	return false;
889	}	896	}
890	spinlock_unlock(&a->lock);	897	mutex_unlock(&a->lock);
891	}	898	}
892		899
893	/* Second, check the leaf node. */	900	/* Second, check the leaf node. */
894	for (i = 0; i < leaf->keys; i++) {	901	for (i = 0; i < leaf->keys; i++) {
895	a = (as_area_t *) leaf->value[i];	902	a = (as_area_t *) leaf->value[i];
896		903
897	if (a == avoid_area)	904	if (a == avoid_area)
898	continue;	905	continue;
899		906
900	spinlock_lock(&a->lock);	907	mutex_lock(&a->lock);
901	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {	908	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
902	spinlock_unlock(&a->lock);	909	mutex_unlock(&a->lock);
903	return false;	910	return false;
904	}	911	}
905	spinlock_unlock(&a->lock);	912	mutex_unlock(&a->lock);
906	}	913	}
907		914
908	/*	915	/*
909	* So far, the area does not conflict with other areas.	916	* So far, the area does not conflict with other areas.
910	* Check if it doesn't conflict with kernel address space.	917	* Check if it doesn't conflict with kernel address space.
Line 915...	Line 922...
915	}	922	}
916		923
917	return true;	924	return true;
918	}	925	}
919		926
920	/** Return size of address space of current task pointed to by base */	927	/** Return size of the address space area with given base. */
921	size_t as_get_size(__address base)	928	size_t as_get_size(__address base)
922	{	929	{
923	ipl_t ipl;	930	ipl_t ipl;
924	as_area_t *src_area;	931	as_area_t *src_area;
925	size_t size;	932	size_t size;
926		933
927	ipl = interrupts_disable();	934	ipl = interrupts_disable();
928	src_area = find_area_and_lock(AS, base);	935	src_area = find_area_and_lock(AS, base);
929	if (src_area){	936	if (src_area){
930	size = src_area->pages * PAGE_SIZE;	937	size = src_area->pages * PAGE_SIZE;
931	spinlock_unlock(&src_area->lock);	938	mutex_unlock(&src_area->lock);
932	} else {	939	} else {
933	size = 0;	940	size = 0;
934	}	941	}
935	interrupts_restore(ipl);	942	interrupts_restore(ipl);
936	return size;	943	return size;

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/mm/as.c – Rev 1358 → 1380