WebSVN – HelenOS – Blame – //branches/tracing/kernel/generic/src/mm/as.c

Rev	Author	Line No.	Line
703	jermar	1	/*
2071	jermar	2	* Copyright (c) 2001-2006 Jakub Jermar
703	jermar	3	* All rights reserved.
		4	*
		5	* Redistribution and use in source and binary forms, with or without
		6	* modification, are permitted provided that the following conditions
		7	* are met:
		8	*
		9	* - Redistributions of source code must retain the above copyright
		10	* notice, this list of conditions and the following disclaimer.
		11	* - Redistributions in binary form must reproduce the above copyright
		12	* notice, this list of conditions and the following disclaimer in the
		13	* documentation and/or other materials provided with the distribution.
		14	* - The name of the author may not be used to endorse or promote products
		15	* derived from this software without specific prior written permission.
		16	*
		17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
		18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
		19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
		20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
		21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
		22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
		23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
		24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
		25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
		26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
		27	*/
		28
1757	jermar	29	/** @addtogroup genericmm
1702	cejka	30	* @{
		31	*/
		32
1248	jermar	33	/**
1702	cejka	34	* @file
1248	jermar	35	* @brief Address space related functions.
		36	*
703	jermar	37	* This file contains address space manipulation functions.
		38	* Roughly speaking, this is a higher-level client of
		39	* Virtual Address Translation (VAT) subsystem.
1248	jermar	40	*
		41	* Functionality provided by this file allows one to
1757	jermar	42	* create address spaces and create, resize and share
1248	jermar	43	* address space areas.
		44	*
		45	* @see page.c
		46	*
703	jermar	47	*/
		48
		49	#include <mm/as.h>
756	jermar	50	#include <arch/mm/as.h>
703	jermar	51	#include <mm/page.h>
		52	#include <mm/frame.h>
814	palkovsky	53	#include <mm/slab.h>
703	jermar	54	#include <mm/tlb.h>
		55	#include <arch/mm/page.h>
		56	#include <genarch/mm/page_pt.h>
1108	jermar	57	#include <genarch/mm/page_ht.h>
727	jermar	58	#include <mm/asid.h>
703	jermar	59	#include <arch/mm/asid.h>
2183	jermar	60	#include <preemption.h>
703	jermar	61	#include <synch/spinlock.h>
1380	jermar	62	#include <synch/mutex.h>
788	jermar	63	#include <adt/list.h>
1147	jermar	64	#include <adt/btree.h>
1235	jermar	65	#include <proc/task.h>
1288	jermar	66	#include <proc/thread.h>
1235	jermar	67	#include <arch/asm.h>
703	jermar	68	#include <panic.h>
		69	#include <debug.h>
1235	jermar	70	#include <print.h>
703	jermar	71	#include <memstr.h>
1070	jermar	72	#include <macros.h>
703	jermar	73	#include <arch.h>
1235	jermar	74	#include <errno.h>
		75	#include <config.h>
1387	jermar	76	#include <align.h>
1235	jermar	77	#include <arch/types.h>
1288	jermar	78	#include <syscall/copy.h>
		79	#include <arch/interrupt.h>
703	jermar	80
2009	jermar	81	#ifdef CONFIG_VIRT_IDX_DCACHE
		82	#include <arch/mm/cache.h>
		83	#endif /* CONFIG_VIRT_IDX_DCACHE */
		84
1757	jermar	85	/**
		86	* Each architecture decides what functions will be used to carry out
		87	* address space operations such as creating or locking page tables.
		88	*/
756	jermar	89	as_operations_t *as_operations = NULL;
703	jermar	90
1890	jermar	91	/**
		92	* Slab for as_t objects.
		93	*/
		94	static slab_cache_t *as_slab;
		95
2087	jermar	96	/**
2170	jermar	97	* This lock serializes access to the ASID subsystem.
		98	* It protects:
		99	* - inactive_as_with_asid_head list
		100	* - as->asid for each as of the as_t type
		101	* - asids_allocated counter
2087	jermar	102	*/
2170	jermar	103	SPINLOCK_INITIALIZE(asidlock);
823	jermar	104
		105	/**
		106	* This list contains address spaces that are not active on any
		107	* processor and that have valid ASID.
		108	*/
		109	LIST_INITIALIZE(inactive_as_with_asid_head);
		110
757	jermar	111	/** Kernel address space. */
		112	as_t *AS_KERNEL = NULL;
		113
3425	svoboda	114	static int area_flags_to_page_flags(int);
		115	static bool check_area_conflicts(as_t , uintptr_t, size_t, as_area_t );
		116	static void sh_info_remove_reference(share_info_t *);
703	jermar	117
1891	jermar	118	static int as_constructor(void *obj, int flags)
		119	{
		120	as_t as = (as_t ) obj;
		121	int rc;
		122
		123	link_initialize(&as->inactive_as_with_asid_link);
4377	svoboda	124	mutex_initialize(&as->lock, MUTEX_PASSIVE);
1891	jermar	125
		126	rc = as_constructor_arch(as, flags);
		127
		128	return rc;
		129	}
		130
		131	static int as_destructor(void *obj)
		132	{
		133	as_t as = (as_t ) obj;
		134
		135	return as_destructor_arch(as);
		136	}
		137
756	jermar	138	/** Initialize address space subsystem. */
		139	void as_init(void)
		140	{
		141	as_arch_init();
2126	decky	142
1891	jermar	143	as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087	jermar	144	as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
1890	jermar	145
789	palkovsky	146	AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383	decky	147	if (!AS_KERNEL)
4377	svoboda	148	panic("Cannot create kernel address space.");
1383	decky	149
4377	svoboda	150	/* Make sure the kernel address space
		151	* reference count never drops to zero.
		152	*/
		153	atomic_set(&AS_KERNEL->refcount, 1);
756	jermar	154	}
		155
757	jermar	156	/** Create address space.
		157	*
3425	svoboda	158	* @param flags Flags that influence the way in wich the address space
		159	* is created.
757	jermar	160	*/
756	jermar	161	as_t *as_create(int flags)
703	jermar	162	{
		163	as_t *as;
		164
1890	jermar	165	as = (as_t *) slab_alloc(as_slab, 0);
1891	jermar	166	(void) as_create_arch(as, 0);
		167
1147	jermar	168	btree_create(&as->as_area_btree);
822	palkovsky	169
		170	if (flags & FLAG_AS_KERNEL)
		171	as->asid = ASID_KERNEL;
		172	else
		173	as->asid = ASID_INVALID;
		174
2183	jermar	175	atomic_set(&as->refcount, 0);
1415	jermar	176	as->cpu_refcount = 0;
2089	decky	177	#ifdef AS_PAGE_TABLE
2106	jermar	178	as->genarch.page_table = page_table_create(flags);
2089	decky	179	#else
		180	page_table_create(flags);
		181	#endif
4377	svoboda	182
703	jermar	183	return as;
		184	}
		185
1468	jermar	186	/** Destroy adress space.
		187	*
2087	jermar	188	* When there are no tasks referencing this address space (i.e. its refcount is
		189	* zero), the address space can be destroyed.
2183	jermar	190	*
		191	* We know that we don't hold any spinlock.
3425	svoboda	192	*
		193	* @param as Address space to be destroyed.
1468	jermar	194	*/
		195	void as_destroy(as_t *as)
973	palkovsky	196	{
1468	jermar	197	ipl_t ipl;
1594	jermar	198	bool cond;
2183	jermar	199	DEADLOCK_PROBE_INIT(p_asidlock);
973	palkovsky	200
2183	jermar	201	ASSERT(atomic_get(&as->refcount) == 0);
1468	jermar	202
		203	/*
		204	* Since there is no reference to this area,
		205	* it is safe not to lock its mutex.
		206	*/
2170	jermar	207
2183	jermar	208	/*
		209	* We need to avoid deadlock between TLB shootdown and asidlock.
		210	* We therefore try to take asid conditionally and if we don't succeed,
		211	* we enable interrupts and try again. This is done while preemption is
		212	* disabled to prevent nested context switches. We also depend on the
		213	* fact that so far no spinlocks are held.
		214	*/
		215	preemption_disable();
		216	ipl = interrupts_read();
		217	retry:
		218	interrupts_disable();
		219	if (!spinlock_trylock(&asidlock)) {
		220	interrupts_enable();
		221	DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
		222	goto retry;
		223	}
		224	preemption_enable(); /* Interrupts disabled, enable preemption */
1587	jermar	225	if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594	jermar	226	if (as != AS && as->cpu_refcount == 0)
1587	jermar	227	list_remove(&as->inactive_as_with_asid_link);
1468	jermar	228	asid_put(as->asid);
		229	}
2170	jermar	230	spinlock_unlock(&asidlock);
1468	jermar	231
		232	/*
		233	* Destroy address space areas of the address space.
1954	jermar	234	* The B+tree must be walked carefully because it is
1594	jermar	235	* also being destroyed.
1468	jermar	236	*/
1594	jermar	237	for (cond = true; cond; ) {
1468	jermar	238	btree_node_t *node;
1594	jermar	239
		240	ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087	jermar	241	node = list_get_instance(as->as_area_btree.leaf_head.next,
		242	btree_node_t, leaf_link);
1594	jermar	243
		244	if ((cond = node->keys)) {
		245	as_area_destroy(as, node->key[0]);
		246	}
1468	jermar	247	}
1495	jermar	248
1483	jermar	249	btree_destroy(&as->as_area_btree);
2089	decky	250	#ifdef AS_PAGE_TABLE
2106	jermar	251	page_table_destroy(as->genarch.page_table);
2089	decky	252	#else
		253	page_table_destroy(NULL);
		254	#endif
1468	jermar	255
		256	interrupts_restore(ipl);
2126	decky	257
1890	jermar	258	slab_free(as_slab, as);
973	palkovsky	259	}
		260
703	jermar	261	/** Create address space area of common attributes.
		262	*
		263	* The created address space area is added to the target address space.
		264	*
3425	svoboda	265	* @param as Target address space.
		266	* @param flags Flags of the area memory.
		267	* @param size Size of area.
		268	* @param base Base address of area.
		269	* @param attrs Attributes of the area.
		270	* @param backend Address space area backend. NULL if no backend is used.
		271	* @param backend_data NULL or a pointer to an array holding two void *.
703	jermar	272	*
3425	svoboda	273	* @return Address space area on success or NULL on failure.
703	jermar	274	*/
2069	jermar	275	as_area_t *
		276	as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
3425	svoboda	277	mem_backend_t backend, mem_backend_data_t backend_data)
703	jermar	278	{
		279	ipl_t ipl;
		280	as_area_t *a;
		281
		282	if (base % PAGE_SIZE)
1048	jermar	283	return NULL;
		284
1233	jermar	285	if (!size)
		286	return NULL;
		287
1048	jermar	288	/* Writeable executable areas are not supported. */
		289	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
		290	return NULL;
703	jermar	291
		292	ipl = interrupts_disable();
1380	jermar	293	mutex_lock(&as->lock);
703	jermar	294
1048	jermar	295	if (!check_area_conflicts(as, base, size, NULL)) {
1380	jermar	296	mutex_unlock(&as->lock);
1048	jermar	297	interrupts_restore(ipl);
		298	return NULL;
		299	}
703	jermar	300
822	palkovsky	301	a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703	jermar	302
3425	svoboda	303	mutex_initialize(&a->lock, MUTEX_PASSIVE);
822	palkovsky	304
1424	jermar	305	a->as = as;
1026	jermar	306	a->flags = flags;
1239	jermar	307	a->attributes = attrs;
1048	jermar	308	a->pages = SIZE2FRAMES(size);
822	palkovsky	309	a->base = base;
1409	jermar	310	a->sh_info = NULL;
		311	a->backend = backend;
1424	jermar	312	if (backend_data)
		313	a->backend_data = *backend_data;
		314	else
3424	svoboda	315	memsetb(&a->backend_data, sizeof(a->backend_data), 0);
1424	jermar	316
1387	jermar	317	btree_create(&a->used_space);
822	palkovsky	318
1147	jermar	319	btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822	palkovsky	320
1380	jermar	321	mutex_unlock(&as->lock);
703	jermar	322	interrupts_restore(ipl);
704	jermar	323
703	jermar	324	return a;
		325	}
		326
1235	jermar	327	/** Find address space area and change it.
		328	*
3425	svoboda	329	* @param as Address space.
		330	* @param address Virtual address belonging to the area to be changed.
		331	* Must be page-aligned.
		332	* @param size New size of the virtual memory block starting at
		333	* address.
		334	* @param flags Flags influencing the remap operation. Currently unused.
1235	jermar	335	*
3425	svoboda	336	* @return Zero on success or a value from @ref errno.h otherwise.
1235	jermar	337	*/
1780	jermar	338	int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235	jermar	339	{
1306	jermar	340	as_area_t *area;
1235	jermar	341	ipl_t ipl;
		342	size_t pages;
		343
		344	ipl = interrupts_disable();
1380	jermar	345	mutex_lock(&as->lock);
1235	jermar	346
		347	/*
		348	* Locate the area.
		349	*/
		350	area = find_area_and_lock(as, address);
		351	if (!area) {
1380	jermar	352	mutex_unlock(&as->lock);
1235	jermar	353	interrupts_restore(ipl);
1306	jermar	354	return ENOENT;
1235	jermar	355	}
		356
1424	jermar	357	if (area->backend == &phys_backend) {
1235	jermar	358	/*
		359	* Remapping of address space areas associated
		360	* with memory mapped devices is not supported.
		361	*/
1380	jermar	362	mutex_unlock(&area->lock);
		363	mutex_unlock(&as->lock);
1235	jermar	364	interrupts_restore(ipl);
1306	jermar	365	return ENOTSUP;
1235	jermar	366	}
1409	jermar	367	if (area->sh_info) {
		368	/*
		369	* Remapping of shared address space areas
		370	* is not supported.
		371	*/
		372	mutex_unlock(&area->lock);
		373	mutex_unlock(&as->lock);
		374	interrupts_restore(ipl);
		375	return ENOTSUP;
		376	}
1235	jermar	377
		378	pages = SIZE2FRAMES((address - area->base) + size);
		379	if (!pages) {
		380	/*
		381	* Zero size address space areas are not allowed.
		382	*/
1380	jermar	383	mutex_unlock(&area->lock);
		384	mutex_unlock(&as->lock);
1235	jermar	385	interrupts_restore(ipl);
1306	jermar	386	return EPERM;
1235	jermar	387	}
		388
		389	if (pages < area->pages) {
1403	jermar	390	bool cond;
3425	svoboda	391	uintptr_t start_free = area->base + pages * PAGE_SIZE;
1235	jermar	392
		393	/*
		394	* Shrinking the area.
		395	* No need to check for overlaps.
		396	*/
1403	jermar	397
		398	/*
1436	jermar	399	* Start TLB shootdown sequence.
		400	*/
3425	svoboda	401	tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base +
2087	jermar	402	pages * PAGE_SIZE, area->pages - pages);
1436	jermar	403
		404	/*
1403	jermar	405	* Remove frames belonging to used space starting from
		406	* the highest addresses downwards until an overlap with
		407	* the resized address space area is found. Note that this
		408	* is also the right way to remove part of the used_space
		409	* B+tree leaf list.
		410	*/
		411	for (cond = true; cond;) {
		412	btree_node_t *node;
		413
		414	ASSERT(!list_empty(&area->used_space.leaf_head));
2087	jermar	415	node =
		416	list_get_instance(area->used_space.leaf_head.prev,
		417	btree_node_t, leaf_link);
1403	jermar	418	if ((cond = (bool) node->keys)) {
1780	jermar	419	uintptr_t b = node->key[node->keys - 1];
2087	jermar	420	count_t c =
		421	(count_t) node->value[node->keys - 1];
2745	decky	422	unsigned int i = 0;
1235	jermar	423
2087	jermar	424	if (overlaps(b, c * PAGE_SIZE, area->base,
2133	jermar	425	pages * PAGE_SIZE)) {
1403	jermar	426
2087	jermar	427	if (b + c * PAGE_SIZE <= start_free) {
1403	jermar	428	/*
2087	jermar	429	* The whole interval fits
		430	* completely in the resized
		431	* address space area.
1403	jermar	432	*/
		433	break;
		434	}
		435
		436	/*
2087	jermar	437	* Part of the interval corresponding
		438	* to b and c overlaps with the resized
		439	* address space area.
1403	jermar	440	*/
		441
		442	cond = false; /* we are almost done */
		443	i = (start_free - b) >> PAGE_WIDTH;
3425	svoboda	444	if (!used_space_remove(area, start_free,
		445	c - i))
4377	svoboda	446	panic("Cannot remove used "
		447	"space.");
1403	jermar	448	} else {
		449	/*
2087	jermar	450	* The interval of used space can be
		451	* completely removed.
1403	jermar	452	*/
		453	if (!used_space_remove(area, b, c))
4377	svoboda	454	panic("Cannot remove used "
		455	"space.");
1403	jermar	456	}
		457
		458	for (; i < c; i++) {
		459	pte_t *pte;
		460
		461	page_table_lock(as, false);
2087	jermar	462	pte = page_mapping_find(as, b +
		463	i * PAGE_SIZE);
		464	ASSERT(pte && PTE_VALID(pte) &&
		465	PTE_PRESENT(pte));
		466	if (area->backend &&
		467	area->backend->frame_free) {
1424	jermar	468	area->backend->frame_free(area,
2087	jermar	469	b + i * PAGE_SIZE,
		470	PTE_GET_FRAME(pte));
1409	jermar	471	}
2087	jermar	472	page_mapping_remove(as, b +
		473	i * PAGE_SIZE);
1403	jermar	474	page_table_unlock(as, false);
		475	}
1235	jermar	476	}
		477	}
1436	jermar	478
1235	jermar	479	/*
1436	jermar	480	* Finish TLB shootdown sequence.
1235	jermar	481	*/
2183	jermar	482
2087	jermar	483	tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
		484	area->pages - pages);
1889	jermar	485	/*
		486	* Invalidate software translation caches (e.g. TSB on sparc64).
		487	*/
2087	jermar	488	as_invalidate_translation_cache(as, area->base +
		489	pages * PAGE_SIZE, area->pages - pages);
2183	jermar	490	tlb_shootdown_finalize();
		491
1235	jermar	492	} else {
		493	/*
		494	* Growing the area.
		495	* Check for overlaps with other address space areas.
		496	*/
2087	jermar	497	if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
		498	area)) {
1380	jermar	499	mutex_unlock(&area->lock);
		500	mutex_unlock(&as->lock);
1235	jermar	501	interrupts_restore(ipl);
1306	jermar	502	return EADDRNOTAVAIL;
1235	jermar	503	}
		504	}
		505
		506	area->pages = pages;
		507
1380	jermar	508	mutex_unlock(&area->lock);
		509	mutex_unlock(&as->lock);
1235	jermar	510	interrupts_restore(ipl);
		511
1306	jermar	512	return 0;
1235	jermar	513	}
		514
1306	jermar	515	/** Destroy address space area.
		516	*
3425	svoboda	517	* @param as Address space.
		518	* @param address Address within the area to be deleted.
1306	jermar	519	*
3425	svoboda	520	* @return Zero on success or a value from @ref errno.h on failure.
1306	jermar	521	*/
1780	jermar	522	int as_area_destroy(as_t *as, uintptr_t address)
1306	jermar	523	{
		524	as_area_t *area;
1780	jermar	525	uintptr_t base;
1495	jermar	526	link_t *cur;
1306	jermar	527	ipl_t ipl;
		528
		529	ipl = interrupts_disable();
1380	jermar	530	mutex_lock(&as->lock);
1306	jermar	531
		532	area = find_area_and_lock(as, address);
		533	if (!area) {
1380	jermar	534	mutex_unlock(&as->lock);
1306	jermar	535	interrupts_restore(ipl);
		536	return ENOENT;
		537	}
		538
1403	jermar	539	base = area->base;
		540
1411	jermar	541	/*
1436	jermar	542	* Start TLB shootdown sequence.
		543	*/
1889	jermar	544	tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436	jermar	545
		546	/*
1411	jermar	547	* Visit only the pages mapped by used_space B+tree.
		548	*/
2087	jermar	549	for (cur = area->used_space.leaf_head.next;
		550	cur != &area->used_space.leaf_head; cur = cur->next) {
1411	jermar	551	btree_node_t *node;
2745	decky	552	unsigned int i;
1403	jermar	553
1495	jermar	554	node = list_get_instance(cur, btree_node_t, leaf_link);
		555	for (i = 0; i < node->keys; i++) {
1780	jermar	556	uintptr_t b = node->key[i];
1495	jermar	557	count_t j;
1411	jermar	558	pte_t *pte;
1403	jermar	559
1495	jermar	560	for (j = 0; j < (count_t) node->value[i]; j++) {
1411	jermar	561	page_table_lock(as, false);
2087	jermar	562	pte = page_mapping_find(as, b + j * PAGE_SIZE);
		563	ASSERT(pte && PTE_VALID(pte) &&
		564	PTE_PRESENT(pte));
		565	if (area->backend &&
		566	area->backend->frame_free) {
		567	area->backend->frame_free(area, b +
2133	jermar	568	j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403	jermar	569	}
2087	jermar	570	page_mapping_remove(as, b + j * PAGE_SIZE);
1411	jermar	571	page_table_unlock(as, false);
1306	jermar	572	}
		573	}
		574	}
1403	jermar	575
1306	jermar	576	/*
1436	jermar	577	* Finish TLB shootdown sequence.
1306	jermar	578	*/
2183	jermar	579
1889	jermar	580	tlb_invalidate_pages(as->asid, area->base, area->pages);
		581	/*
2087	jermar	582	* Invalidate potential software translation caches (e.g. TSB on
		583	* sparc64).
1889	jermar	584	*/
		585	as_invalidate_translation_cache(as, area->base, area->pages);
2183	jermar	586	tlb_shootdown_finalize();
1889	jermar	587
1436	jermar	588	btree_destroy(&area->used_space);
1306	jermar	589
1309	jermar	590	area->attributes \|= AS_AREA_ATTR_PARTIAL;
1409	jermar	591
		592	if (area->sh_info)
		593	sh_info_remove_reference(area->sh_info);
		594
1380	jermar	595	mutex_unlock(&area->lock);
1306	jermar	596
		597	/*
		598	* Remove the empty area from address space.
		599	*/
1889	jermar	600	btree_remove(&as->as_area_btree, base, NULL);
1306	jermar	601
1309	jermar	602	free(area);
		603
1889	jermar	604	mutex_unlock(&as->lock);
1306	jermar	605	interrupts_restore(ipl);
		606	return 0;
		607	}
		608
1413	jermar	609	/** Share address space area with another or the same address space.
1235	jermar	610	*
1424	jermar	611	* Address space area mapping is shared with a new address space area.
		612	* If the source address space area has not been shared so far,
		613	* a new sh_info is created. The new address space area simply gets the
		614	* sh_info of the source area. The process of duplicating the
		615	* mapping is done through the backend share function.
1413	jermar	616	*
3425	svoboda	617	* @param src_as Pointer to source address space.
		618	* @param src_base Base address of the source address space area.
		619	* @param acc_size Expected size of the source area.
		620	* @param dst_as Pointer to destination address space.
		621	* @param dst_base Target base address.
1417	jermar	622	* @param dst_flags_mask Destination address space area flags mask.
1235	jermar	623	*
3425	svoboda	624	* @return Zero on success or ENOENT if there is no such task or if
		625	* there is no such address space area, EPERM if there was
		626	* a problem in accepting the area or ENOMEM if there was a
		627	* problem in allocating destination address space area.
		628	* ENOTSUP is returned if the address space area backend
		629	* does not support sharing.
1235	jermar	630	*/
1780	jermar	631	int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647	jermar	632	as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235	jermar	633	{
		634	ipl_t ipl;
1239	jermar	635	int src_flags;
		636	size_t src_size;
		637	as_area_t src_area, dst_area;
1413	jermar	638	share_info_t *sh_info;
1424	jermar	639	mem_backend_t *src_backend;
		640	mem_backend_data_t src_backend_data;
1434	palkovsky	641
1235	jermar	642	ipl = interrupts_disable();
1380	jermar	643	mutex_lock(&src_as->lock);
1329	palkovsky	644	src_area = find_area_and_lock(src_as, src_base);
1239	jermar	645	if (!src_area) {
1238	jermar	646	/*
		647	* Could not find the source address space area.
		648	*/
1380	jermar	649	mutex_unlock(&src_as->lock);
1238	jermar	650	interrupts_restore(ipl);
		651	return ENOENT;
		652	}
2007	jermar	653
1424	jermar	654	if (!src_area->backend \|\| !src_area->backend->share) {
1413	jermar	655	/*
1851	jermar	656	* There is no backend or the backend does not
1424	jermar	657	* know how to share the area.
1413	jermar	658	*/
		659	mutex_unlock(&src_area->lock);
		660	mutex_unlock(&src_as->lock);
		661	interrupts_restore(ipl);
		662	return ENOTSUP;
		663	}
		664
1239	jermar	665	src_size = src_area->pages * PAGE_SIZE;
		666	src_flags = src_area->flags;
1424	jermar	667	src_backend = src_area->backend;
		668	src_backend_data = src_area->backend_data;
1544	palkovsky	669
		670	/* Share the cacheable flag from the original mapping */
		671	if (src_flags & AS_AREA_CACHEABLE)
		672	dst_flags_mask \|= AS_AREA_CACHEABLE;
		673
2087	jermar	674	if (src_size != acc_size \|\|
		675	(src_flags & dst_flags_mask) != dst_flags_mask) {
1413	jermar	676	mutex_unlock(&src_area->lock);
		677	mutex_unlock(&src_as->lock);
1235	jermar	678	interrupts_restore(ipl);
		679	return EPERM;
		680	}
1413	jermar	681
1235	jermar	682	/*
1413	jermar	683	* Now we are committed to sharing the area.
1954	jermar	684	* First, prepare the area for sharing.
1413	jermar	685	* Then it will be safe to unlock it.
		686	*/
		687	sh_info = src_area->sh_info;
		688	if (!sh_info) {
		689	sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
3425	svoboda	690	mutex_initialize(&sh_info->lock, MUTEX_PASSIVE);
1413	jermar	691	sh_info->refcount = 2;
		692	btree_create(&sh_info->pagemap);
		693	src_area->sh_info = sh_info;
2647	jermar	694	/*
		695	* Call the backend to setup sharing.
		696	*/
		697	src_area->backend->share(src_area);
1413	jermar	698	} else {
		699	mutex_lock(&sh_info->lock);
		700	sh_info->refcount++;
		701	mutex_unlock(&sh_info->lock);
		702	}
		703
		704	mutex_unlock(&src_area->lock);
		705	mutex_unlock(&src_as->lock);
		706
		707	/*
1239	jermar	708	* Create copy of the source address space area.
		709	* The destination area is created with AS_AREA_ATTR_PARTIAL
		710	* attribute set which prevents race condition with
		711	* preliminary as_page_fault() calls.
1417	jermar	712	* The flags of the source area are masked against dst_flags_mask
		713	* to support sharing in less privileged mode.
1235	jermar	714	*/
1461	palkovsky	715	dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087	jermar	716	AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239	jermar	717	if (!dst_area) {
1235	jermar	718	/*
		719	* Destination address space area could not be created.
		720	*/
1413	jermar	721	sh_info_remove_reference(sh_info);
		722
1235	jermar	723	interrupts_restore(ipl);
		724	return ENOMEM;
		725	}
2009	jermar	726
1235	jermar	727	/*
1239	jermar	728	* Now the destination address space area has been
		729	* fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413	jermar	730	* attribute and set the sh_info.
1239	jermar	731	*/
2009	jermar	732	mutex_lock(&dst_as->lock);
1380	jermar	733	mutex_lock(&dst_area->lock);
1239	jermar	734	dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413	jermar	735	dst_area->sh_info = sh_info;
1380	jermar	736	mutex_unlock(&dst_area->lock);
2009	jermar	737	mutex_unlock(&dst_as->lock);
		738
1235	jermar	739	interrupts_restore(ipl);
		740
		741	return 0;
		742	}
		743
1423	jermar	744	/** Check access mode for address space area.
		745	*
		746	* The address space area must be locked prior to this call.
		747	*
3425	svoboda	748	* @param area Address space area.
		749	* @param access Access mode.
1423	jermar	750	*
3425	svoboda	751	* @return False if access violates area's permissions, true
		752	* otherwise.
1423	jermar	753	*/
		754	bool as_area_check_access(as_area_t *area, pf_access_t access)
		755	{
		756	int flagmap[] = {
		757	[PF_ACCESS_READ] = AS_AREA_READ,
		758	[PF_ACCESS_WRITE] = AS_AREA_WRITE,
		759	[PF_ACCESS_EXEC] = AS_AREA_EXEC
		760	};
		761
		762	if (!(area->flags & flagmap[access]))
		763	return false;
		764
		765	return true;
		766	}
		767
3425	svoboda	768	/** Change adress space area flags.
		769	*
		770	* The idea is to have the same data, but with a different access mode.
		771	* This is needed e.g. for writing code into memory and then executing it.
		772	* In order for this to work properly, this may copy the data
		773	* into private anonymous memory (unless it's already there).
		774	*
4377	svoboda	775	* @param as Address space.
		776	* @param flags Flags of the area memory.
		777	* @param address Address within the area to be changed.
3425	svoboda	778	*
4377	svoboda	779	* @return Zero on success or a value from @ref errno.h on failure.
		780	*
3425	svoboda	781	*/
		782	int as_area_change_flags(as_t *as, int flags, uintptr_t address)
		783	{
		784	as_area_t *area;
		785	uintptr_t base;
		786	link_t *cur;
		787	ipl_t ipl;
		788	int page_flags;
		789	uintptr_t *old_frame;
		790	index_t frame_idx;
		791	count_t used_pages;
4377	svoboda	792
3425	svoboda	793	/* Flags for the new memory mapping */
		794	page_flags = area_flags_to_page_flags(flags);
		795
		796	ipl = interrupts_disable();
		797	mutex_lock(&as->lock);
		798
		799	area = find_area_and_lock(as, address);
		800	if (!area) {
		801	mutex_unlock(&as->lock);
		802	interrupts_restore(ipl);
		803	return ENOENT;
		804	}
		805
4377	svoboda	806	if ((area->sh_info) \|\| (area->backend != &anon_backend)) {
3425	svoboda	807	/* Copying shared areas not supported yet */
		808	/* Copying non-anonymous memory not supported yet */
		809	mutex_unlock(&area->lock);
		810	mutex_unlock(&as->lock);
		811	interrupts_restore(ipl);
		812	return ENOTSUP;
		813	}
		814
		815	base = area->base;
		816
		817	/*
		818	* Compute total number of used pages in the used_space B+tree
		819	*/
		820	used_pages = 0;
		821
		822	for (cur = area->used_space.leaf_head.next;
		823	cur != &area->used_space.leaf_head; cur = cur->next) {
		824	btree_node_t *node;
		825	unsigned int i;
		826
		827	node = list_get_instance(cur, btree_node_t, leaf_link);
		828	for (i = 0; i < node->keys; i++) {
		829	used_pages += (count_t) node->value[i];
		830	}
		831	}
		832
		833	/* An array for storing frame numbers */
		834	old_frame = malloc(used_pages * sizeof(uintptr_t), 0);
		835
		836	/*
		837	* Start TLB shootdown sequence.
		838	*/
		839	tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
		840
		841	/*
		842	* Remove used pages from page tables and remember their frame
		843	* numbers.
		844	*/
		845	frame_idx = 0;
		846
		847	for (cur = area->used_space.leaf_head.next;
		848	cur != &area->used_space.leaf_head; cur = cur->next) {
		849	btree_node_t *node;
		850	unsigned int i;
		851
		852	node = list_get_instance(cur, btree_node_t, leaf_link);
		853	for (i = 0; i < node->keys; i++) {
		854	uintptr_t b = node->key[i];
		855	count_t j;
		856	pte_t *pte;
		857
		858	for (j = 0; j < (count_t) node->value[i]; j++) {
		859	page_table_lock(as, false);
		860	pte = page_mapping_find(as, b + j * PAGE_SIZE);
		861	ASSERT(pte && PTE_VALID(pte) &&
		862	PTE_PRESENT(pte));
		863	old_frame[frame_idx++] = PTE_GET_FRAME(pte);
		864
		865	/* Remove old mapping */
		866	page_mapping_remove(as, b + j * PAGE_SIZE);
		867	page_table_unlock(as, false);
		868	}
		869	}
		870	}
		871
		872	/*
		873	* Finish TLB shootdown sequence.
		874	*/
		875
		876	tlb_invalidate_pages(as->asid, area->base, area->pages);
4377	svoboda	877
3425	svoboda	878	/*
		879	* Invalidate potential software translation caches (e.g. TSB on
		880	* sparc64).
		881	*/
		882	as_invalidate_translation_cache(as, area->base, area->pages);
		883	tlb_shootdown_finalize();
		884
		885	/*
		886	* Set the new flags.
		887	*/
		888	area->flags = flags;
		889
		890	/*
		891	* Map pages back in with new flags. This step is kept separate
		892	* so that the memory area could not be accesed with both the old and
		893	* the new flags at once.
		894	*/
		895	frame_idx = 0;
		896
		897	for (cur = area->used_space.leaf_head.next;
		898	cur != &area->used_space.leaf_head; cur = cur->next) {
		899	btree_node_t *node;
		900	unsigned int i;
		901
		902	node = list_get_instance(cur, btree_node_t, leaf_link);
		903	for (i = 0; i < node->keys; i++) {
		904	uintptr_t b = node->key[i];
		905	count_t j;
		906
		907	for (j = 0; j < (count_t) node->value[i]; j++) {
		908	page_table_lock(as, false);
		909
		910	/* Insert the new mapping */
		911	page_mapping_insert(as, b + j * PAGE_SIZE,
		912	old_frame[frame_idx++], page_flags);
		913
		914	page_table_unlock(as, false);
		915	}
		916	}
		917	}
		918
		919	free(old_frame);
		920
		921	mutex_unlock(&area->lock);
		922	mutex_unlock(&as->lock);
		923	interrupts_restore(ipl);
		924
		925	return 0;
		926	}
		927
		928
703	jermar	929	/** Handle page fault within the current address space.
		930	*
3425	svoboda	931	* This is the high-level page fault handler. It decides whether the page fault
		932	* can be resolved by any backend and if so, it invokes the backend to resolve
		933	* the page fault.
1409	jermar	934	*
703	jermar	935	* Interrupts are assumed disabled.
		936	*
3425	svoboda	937	* @param page Faulting page.
		938	* @param access Access mode that caused the page fault (i.e.
		939	* read/write/exec).
		940	* @param istate Pointer to the interrupted state.
703	jermar	941	*
3425	svoboda	942	* @return AS_PF_FAULT on page fault, AS_PF_OK on success or
		943	* AS_PF_DEFER if the fault was caused by copy_to_uspace()
		944	* or copy_from_uspace().
703	jermar	945	*/
1780	jermar	946	int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703	jermar	947	{
1044	jermar	948	pte_t *pte;
977	jermar	949	as_area_t *area;
703	jermar	950
1380	jermar	951	if (!THREAD)
1409	jermar	952	return AS_PF_FAULT;
1380	jermar	953
703	jermar	954	ASSERT(AS);
1044	jermar	955
1380	jermar	956	mutex_lock(&AS->lock);
977	jermar	957	area = find_area_and_lock(AS, page);
703	jermar	958	if (!area) {
		959	/*
		960	* No area contained mapping for 'page'.
		961	* Signal page fault to low-level handler.
		962	*/
1380	jermar	963	mutex_unlock(&AS->lock);
1288	jermar	964	goto page_fault;
703	jermar	965	}
		966
1239	jermar	967	if (area->attributes & AS_AREA_ATTR_PARTIAL) {
		968	/*
		969	* The address space area is not fully initialized.
		970	* Avoid possible race by returning error.
		971	*/
1380	jermar	972	mutex_unlock(&area->lock);
		973	mutex_unlock(&AS->lock);
1288	jermar	974	goto page_fault;
1239	jermar	975	}
		976
1424	jermar	977	if (!area->backend \|\| !area->backend->page_fault) {
1409	jermar	978	/*
		979	* The address space area is not backed by any backend
		980	* or the backend cannot handle page faults.
		981	*/
		982	mutex_unlock(&area->lock);
		983	mutex_unlock(&AS->lock);
		984	goto page_fault;
		985	}
1179	jermar	986
1044	jermar	987	page_table_lock(AS, false);
		988
703	jermar	989	/*
3425	svoboda	990	* To avoid race condition between two page faults on the same address,
		991	* we need to make sure the mapping has not been already inserted.
1044	jermar	992	*/
		993	if ((pte = page_mapping_find(AS, page))) {
		994	if (PTE_PRESENT(pte)) {
1423	jermar	995	if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) \|\|
2087	jermar	996	(access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) \|\|
		997	(access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423	jermar	998	page_table_unlock(AS, false);
		999	mutex_unlock(&area->lock);
		1000	mutex_unlock(&AS->lock);
		1001	return AS_PF_OK;
		1002	}
1044	jermar	1003	}
		1004	}
1409	jermar	1005
1044	jermar	1006	/*
1409	jermar	1007	* Resort to the backend page fault handler.
703	jermar	1008	*/
1424	jermar	1009	if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409	jermar	1010	page_table_unlock(AS, false);
		1011	mutex_unlock(&area->lock);
		1012	mutex_unlock(&AS->lock);
		1013	goto page_fault;
		1014	}
703	jermar	1015
1044	jermar	1016	page_table_unlock(AS, false);
1380	jermar	1017	mutex_unlock(&area->lock);
		1018	mutex_unlock(&AS->lock);
1288	jermar	1019	return AS_PF_OK;
		1020
		1021	page_fault:
		1022	if (THREAD->in_copy_from_uspace) {
		1023	THREAD->in_copy_from_uspace = false;
2087	jermar	1024	istate_set_retaddr(istate,
		1025	(uintptr_t) &memcpy_from_uspace_failover_address);
1288	jermar	1026	} else if (THREAD->in_copy_to_uspace) {
		1027	THREAD->in_copy_to_uspace = false;
2087	jermar	1028	istate_set_retaddr(istate,
		1029	(uintptr_t) &memcpy_to_uspace_failover_address);
1288	jermar	1030	} else {
		1031	return AS_PF_FAULT;
		1032	}
		1033
		1034	return AS_PF_DEFER;
703	jermar	1035	}
		1036
823	jermar	1037	/** Switch address spaces.
703	jermar	1038	*
1380	jermar	1039	* Note that this function cannot sleep as it is essentially a part of
2170	jermar	1040	* scheduling. Sleeping here would lead to deadlock on wakeup. Another
		1041	* thing which is forbidden in this context is locking the address space.
1380	jermar	1042	*
2183	jermar	1043	* When this function is enetered, no spinlocks may be held.
		1044	*
3425	svoboda	1045	* @param old Old address space or NULL.
		1046	* @param new New address space.
703	jermar	1047	*/
2106	jermar	1048	void as_switch(as_t old_as, as_t new_as)
703	jermar	1049	{
2183	jermar	1050	DEADLOCK_PROBE_INIT(p_asidlock);
		1051	preemption_disable();
		1052	retry:
		1053	(void) interrupts_disable();
		1054	if (!spinlock_trylock(&asidlock)) {
		1055	/*
		1056	* Avoid deadlock with TLB shootdown.
		1057	* We can enable interrupts here because
		1058	* preemption is disabled. We should not be
		1059	* holding any other lock.
		1060	*/
		1061	(void) interrupts_enable();
		1062	DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
		1063	goto retry;
		1064	}
		1065	preemption_enable();
703	jermar	1066
		1067	/*
823	jermar	1068	* First, take care of the old address space.
		1069	*/
2106	jermar	1070	if (old_as) {
		1071	ASSERT(old_as->cpu_refcount);
		1072	if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823	jermar	1073	/*
		1074	* The old address space is no longer active on
		1075	* any processor. It can be appended to the
		1076	* list of inactive address spaces with assigned
		1077	* ASID.
		1078	*/
2141	jermar	1079	ASSERT(old_as->asid != ASID_INVALID);
		1080	list_append(&old_as->inactive_as_with_asid_link,
		1081	&inactive_as_with_asid_head);
823	jermar	1082	}
1890	jermar	1083
		1084	/*
		1085	* Perform architecture-specific tasks when the address space
		1086	* is being removed from the CPU.
		1087	*/
2106	jermar	1088	as_deinstall_arch(old_as);
823	jermar	1089	}
		1090
		1091	/*
		1092	* Second, prepare the new address space.
		1093	*/
2106	jermar	1094	if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170	jermar	1095	if (new_as->asid != ASID_INVALID)
2106	jermar	1096	list_remove(&new_as->inactive_as_with_asid_link);
2170	jermar	1097	else
		1098	new_as->asid = asid_get();
823	jermar	1099	}
2106	jermar	1100	#ifdef AS_PAGE_TABLE
		1101	SET_PTL0_ADDRESS(new_as->genarch.page_table);
		1102	#endif
823	jermar	1103
		1104	/*
703	jermar	1105	* Perform architecture-specific steps.
727	jermar	1106	* (e.g. write ASID to hardware register etc.)
703	jermar	1107	*/
2106	jermar	1108	as_install_arch(new_as);
2170	jermar	1109
		1110	spinlock_unlock(&asidlock);
703	jermar	1111
2106	jermar	1112	AS = new_as;
703	jermar	1113	}
754	jermar	1114
1235	jermar	1115	/** Convert address space area flags to page flags.
754	jermar	1116	*
3425	svoboda	1117	* @param aflags Flags of some address space area.
754	jermar	1118	*
3425	svoboda	1119	* @return Flags to be passed to page_mapping_insert().
754	jermar	1120	*/
1235	jermar	1121	int area_flags_to_page_flags(int aflags)
754	jermar	1122	{
		1123	int flags;
		1124
1178	jermar	1125	flags = PAGE_USER \| PAGE_PRESENT;
754	jermar	1126
1235	jermar	1127	if (aflags & AS_AREA_READ)
1026	jermar	1128	flags \|= PAGE_READ;
		1129
1235	jermar	1130	if (aflags & AS_AREA_WRITE)
1026	jermar	1131	flags \|= PAGE_WRITE;
		1132
1235	jermar	1133	if (aflags & AS_AREA_EXEC)
1026	jermar	1134	flags \|= PAGE_EXEC;
		1135
1424	jermar	1136	if (aflags & AS_AREA_CACHEABLE)
1178	jermar	1137	flags \|= PAGE_CACHEABLE;
		1138
754	jermar	1139	return flags;
		1140	}
756	jermar	1141
1235	jermar	1142	/** Compute flags for virtual address translation subsytem.
		1143	*
		1144	* The address space area must be locked.
		1145	* Interrupts must be disabled.
		1146	*
3425	svoboda	1147	* @param a Address space area.
1235	jermar	1148	*
3425	svoboda	1149	* @return Flags to be used in page_mapping_insert().
1235	jermar	1150	*/
1409	jermar	1151	int as_area_get_flags(as_area_t *a)
1235	jermar	1152	{
		1153	return area_flags_to_page_flags(a->flags);
		1154	}
		1155
756	jermar	1156	/** Create page table.
		1157	*
3425	svoboda	1158	* Depending on architecture, create either address space private or global page
		1159	* table.
756	jermar	1160	*
3425	svoboda	1161	* @param flags Flags saying whether the page table is for the kernel
		1162	* address space.
756	jermar	1163	*
3425	svoboda	1164	* @return First entry of the page table.
756	jermar	1165	*/
		1166	pte_t *page_table_create(int flags)
		1167	{
2125	decky	1168	ASSERT(as_operations);
		1169	ASSERT(as_operations->page_table_create);
		1170
		1171	return as_operations->page_table_create(flags);
756	jermar	1172	}
977	jermar	1173
1468	jermar	1174	/** Destroy page table.
		1175	*
		1176	* Destroy page table in architecture specific way.
		1177	*
3425	svoboda	1178	* @param page_table Physical address of PTL0.
1468	jermar	1179	*/
		1180	void page_table_destroy(pte_t *page_table)
		1181	{
2125	decky	1182	ASSERT(as_operations);
		1183	ASSERT(as_operations->page_table_destroy);
		1184
		1185	as_operations->page_table_destroy(page_table);
1468	jermar	1186	}
		1187
1044	jermar	1188	/** Lock page table.
		1189	*
		1190	* This function should be called before any page_mapping_insert(),
		1191	* page_mapping_remove() and page_mapping_find().
		1192	*
		1193	* Locking order is such that address space areas must be locked
		1194	* prior to this call. Address space can be locked prior to this
		1195	* call in which case the lock argument is false.
		1196	*
3425	svoboda	1197	* @param as Address space.
		1198	* @param lock If false, do not attempt to lock as->lock.
1044	jermar	1199	*/
		1200	void page_table_lock(as_t *as, bool lock)
		1201	{
		1202	ASSERT(as_operations);
		1203	ASSERT(as_operations->page_table_lock);
2125	decky	1204
1044	jermar	1205	as_operations->page_table_lock(as, lock);
		1206	}
		1207
		1208	/** Unlock page table.
		1209	*
3425	svoboda	1210	* @param as Address space.
		1211	* @param unlock If false, do not attempt to unlock as->lock.
1044	jermar	1212	*/
		1213	void page_table_unlock(as_t *as, bool unlock)
		1214	{
		1215	ASSERT(as_operations);
		1216	ASSERT(as_operations->page_table_unlock);
2125	decky	1217
1044	jermar	1218	as_operations->page_table_unlock(as, unlock);
		1219	}
		1220
977	jermar	1221
		1222	/** Find address space area and lock it.
		1223	*
		1224	* The address space must be locked and interrupts must be disabled.
		1225	*
3425	svoboda	1226	* @param as Address space.
		1227	* @param va Virtual address.
977	jermar	1228	*
3425	svoboda	1229	* @return Locked address space area containing va on success or
		1230	* NULL on failure.
977	jermar	1231	*/
1780	jermar	1232	as_area_t find_area_and_lock(as_t as, uintptr_t va)
977	jermar	1233	{
		1234	as_area_t *a;
1147	jermar	1235	btree_node_t leaf, lnode;
2745	decky	1236	unsigned int i;
977	jermar	1237
1147	jermar	1238	a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
		1239	if (a) {
		1240	/* va is the base address of an address space area */
1380	jermar	1241	mutex_lock(&a->lock);
1147	jermar	1242	return a;
		1243	}
		1244
		1245	/*
1150	jermar	1246	* Search the leaf node and the righmost record of its left neighbour
1147	jermar	1247	* to find out whether this is a miss or va belongs to an address
		1248	* space area found there.
		1249	*/
		1250
		1251	/* First, search the leaf node itself. */
		1252	for (i = 0; i < leaf->keys; i++) {
		1253	a = (as_area_t *) leaf->value[i];
1380	jermar	1254	mutex_lock(&a->lock);
1147	jermar	1255	if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
		1256	return a;
		1257	}
1380	jermar	1258	mutex_unlock(&a->lock);
1147	jermar	1259	}
977	jermar	1260
1147	jermar	1261	/*
1150	jermar	1262	* Second, locate the left neighbour and test its last record.
1148	jermar	1263	* Because of its position in the B+tree, it must have base < va.
1147	jermar	1264	*/
2087	jermar	1265	lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
		1266	if (lnode) {
1147	jermar	1267	a = (as_area_t *) lnode->value[lnode->keys - 1];
1380	jermar	1268	mutex_lock(&a->lock);
1147	jermar	1269	if (va < a->base + a->pages * PAGE_SIZE) {
1048	jermar	1270	return a;
1147	jermar	1271	}
1380	jermar	1272	mutex_unlock(&a->lock);
977	jermar	1273	}
		1274
		1275	return NULL;
		1276	}
1048	jermar	1277
		1278	/** Check area conflicts with other areas.
		1279	*
		1280	* The address space must be locked and interrupts must be disabled.
		1281	*
3425	svoboda	1282	* @param as Address space.
		1283	* @param va Starting virtual address of the area being tested.
		1284	* @param size Size of the area being tested.
		1285	* @param avoid_area Do not touch this area.
1048	jermar	1286	*
3425	svoboda	1287	* @return True if there is no conflict, false otherwise.
1048	jermar	1288	*/
3425	svoboda	1289	bool
		1290	check_area_conflicts(as_t as, uintptr_t va, size_t size, as_area_t avoid_area)
1048	jermar	1291	{
		1292	as_area_t *a;
1147	jermar	1293	btree_node_t leaf, node;
2745	decky	1294	unsigned int i;
1048	jermar	1295
1070	jermar	1296	/*
		1297	* We don't want any area to have conflicts with NULL page.
		1298	*/
		1299	if (overlaps(va, size, NULL, PAGE_SIZE))
		1300	return false;
		1301
1147	jermar	1302	/*
		1303	* The leaf node is found in O(log n), where n is proportional to
		1304	* the number of address space areas belonging to as.
		1305	* The check for conflicts is then attempted on the rightmost
1150	jermar	1306	* record in the left neighbour, the leftmost record in the right
		1307	* neighbour and all records in the leaf node itself.
1147	jermar	1308	*/
1048	jermar	1309
1147	jermar	1310	if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
		1311	if (a != avoid_area)
		1312	return false;
		1313	}
		1314
		1315	/* First, check the two border cases. */
1150	jermar	1316	if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147	jermar	1317	a = (as_area_t *) node->value[node->keys - 1];
1380	jermar	1318	mutex_lock(&a->lock);
1147	jermar	1319	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1320	mutex_unlock(&a->lock);
1147	jermar	1321	return false;
		1322	}
1380	jermar	1323	mutex_unlock(&a->lock);
1147	jermar	1324	}
2087	jermar	1325	node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
		1326	if (node) {
1147	jermar	1327	a = (as_area_t *) node->value[0];
1380	jermar	1328	mutex_lock(&a->lock);
1147	jermar	1329	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1330	mutex_unlock(&a->lock);
1147	jermar	1331	return false;
		1332	}
1380	jermar	1333	mutex_unlock(&a->lock);
1147	jermar	1334	}
		1335
		1336	/* Second, check the leaf node. */
		1337	for (i = 0; i < leaf->keys; i++) {
		1338	a = (as_area_t *) leaf->value[i];
		1339
1048	jermar	1340	if (a == avoid_area)
		1341	continue;
1147	jermar	1342
1380	jermar	1343	mutex_lock(&a->lock);
1147	jermar	1344	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1345	mutex_unlock(&a->lock);
1147	jermar	1346	return false;
		1347	}
1380	jermar	1348	mutex_unlock(&a->lock);
1048	jermar	1349	}
		1350
1070	jermar	1351	/*
		1352	* So far, the area does not conflict with other areas.
		1353	* Check if it doesn't conflict with kernel address space.
		1354	*/
		1355	if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
		1356	return !overlaps(va, size,
2087	jermar	1357	KERNEL_ADDRESS_SPACE_START,
		1358	KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070	jermar	1359	}
		1360
1048	jermar	1361	return true;
		1362	}
1235	jermar	1363
2556	jermar	1364	/** Return size of the address space area with given base.
		1365	*
		1366	* @param base Arbitrary address insede the address space area.
		1367	*
		1368	* @return Size of the address space area in bytes or zero if it
		1369	* does not exist.
		1370	*/
		1371	size_t as_area_get_size(uintptr_t base)
1329	palkovsky	1372	{
		1373	ipl_t ipl;
		1374	as_area_t *src_area;
		1375	size_t size;
		1376
		1377	ipl = interrupts_disable();
		1378	src_area = find_area_and_lock(AS, base);
3425	svoboda	1379	if (src_area) {
1329	palkovsky	1380	size = src_area->pages * PAGE_SIZE;
1380	jermar	1381	mutex_unlock(&src_area->lock);
1329	palkovsky	1382	} else {
		1383	size = 0;
		1384	}
		1385	interrupts_restore(ipl);
		1386	return size;
		1387	}
		1388
1387	jermar	1389	/** Mark portion of address space area as used.
		1390	*
		1391	* The address space area must be already locked.
		1392	*
3425	svoboda	1393	* @param a Address space area.
		1394	* @param page First page to be marked.
		1395	* @param count Number of page to be marked.
1387	jermar	1396	*
3425	svoboda	1397	* @return Zero on failure and non-zero on success.
1387	jermar	1398	*/
1780	jermar	1399	int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387	jermar	1400	{
		1401	btree_node_t leaf, node;
		1402	count_t pages;
2745	decky	1403	unsigned int i;
1387	jermar	1404
		1405	ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
		1406	ASSERT(count);
		1407
		1408	pages = (count_t) btree_search(&a->used_space, page, &leaf);
		1409	if (pages) {
		1410	/*
		1411	* We hit the beginning of some used space.
		1412	*/
		1413	return 0;
		1414	}
		1415
1437	jermar	1416	if (!leaf->keys) {
		1417	btree_insert(&a->used_space, page, (void *) count, leaf);
		1418	return 1;
		1419	}
		1420
1387	jermar	1421	node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
		1422	if (node) {
2087	jermar	1423	uintptr_t left_pg = node->key[node->keys - 1];
		1424	uintptr_t right_pg = leaf->key[0];
		1425	count_t left_cnt = (count_t) node->value[node->keys - 1];
		1426	count_t right_cnt = (count_t) leaf->value[0];
1387	jermar	1427
		1428	/*
		1429	* Examine the possibility that the interval fits
		1430	* somewhere between the rightmost interval of
		1431	* the left neigbour and the first interval of the leaf.
		1432	*/
		1433
		1434	if (page >= right_pg) {
		1435	/* Do nothing. */
2087	jermar	1436	} else if (overlaps(page, count * PAGE_SIZE, left_pg,
		1437	left_cnt * PAGE_SIZE)) {
1387	jermar	1438	/* The interval intersects with the left interval. */
		1439	return 0;
2087	jermar	1440	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1441	right_cnt * PAGE_SIZE)) {
1387	jermar	1442	/* The interval intersects with the right interval. */
		1443	return 0;
2087	jermar	1444	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1445	(page + count * PAGE_SIZE == right_pg)) {
		1446	/*
		1447	* The interval can be added by merging the two already
		1448	* present intervals.
		1449	*/
1403	jermar	1450	node->value[node->keys - 1] += count + right_cnt;
1387	jermar	1451	btree_remove(&a->used_space, right_pg, leaf);
		1452	return 1;
2087	jermar	1453	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1454	/*
		1455	* The interval can be added by simply growing the left
		1456	* interval.
		1457	*/
1403	jermar	1458	node->value[node->keys - 1] += count;
1387	jermar	1459	return 1;
2087	jermar	1460	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1461	/*
2087	jermar	1462	* The interval can be addded by simply moving base of
		1463	* the right interval down and increasing its size
		1464	* accordingly.
1387	jermar	1465	*/
1403	jermar	1466	leaf->value[0] += count;
1387	jermar	1467	leaf->key[0] = page;
		1468	return 1;
		1469	} else {
		1470	/*
		1471	* The interval is between both neigbouring intervals,
		1472	* but cannot be merged with any of them.
		1473	*/
2087	jermar	1474	btree_insert(&a->used_space, page, (void *) count,
		1475	leaf);
1387	jermar	1476	return 1;
		1477	}
		1478	} else if (page < leaf->key[0]) {
1780	jermar	1479	uintptr_t right_pg = leaf->key[0];
1387	jermar	1480	count_t right_cnt = (count_t) leaf->value[0];
		1481
		1482	/*
2087	jermar	1483	* Investigate the border case in which the left neighbour does
		1484	* not exist but the interval fits from the left.
1387	jermar	1485	*/
		1486
2087	jermar	1487	if (overlaps(page, count * PAGE_SIZE, right_pg,
		1488	right_cnt * PAGE_SIZE)) {
1387	jermar	1489	/* The interval intersects with the right interval. */
		1490	return 0;
2087	jermar	1491	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1492	/*
2087	jermar	1493	* The interval can be added by moving the base of the
		1494	* right interval down and increasing its size
		1495	* accordingly.
1387	jermar	1496	*/
		1497	leaf->key[0] = page;
1403	jermar	1498	leaf->value[0] += count;
1387	jermar	1499	return 1;
		1500	} else {
		1501	/*
		1502	* The interval doesn't adjoin with the right interval.
		1503	* It must be added individually.
		1504	*/
2087	jermar	1505	btree_insert(&a->used_space, page, (void *) count,
		1506	leaf);
1387	jermar	1507	return 1;
		1508	}
		1509	}
		1510
		1511	node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
		1512	if (node) {
2087	jermar	1513	uintptr_t left_pg = leaf->key[leaf->keys - 1];
		1514	uintptr_t right_pg = node->key[0];
		1515	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1516	count_t right_cnt = (count_t) node->value[0];
1387	jermar	1517
		1518	/*
		1519	* Examine the possibility that the interval fits
		1520	* somewhere between the leftmost interval of
		1521	* the right neigbour and the last interval of the leaf.
		1522	*/
		1523
		1524	if (page < left_pg) {
		1525	/* Do nothing. */
2087	jermar	1526	} else if (overlaps(page, count * PAGE_SIZE, left_pg,
		1527	left_cnt * PAGE_SIZE)) {
1387	jermar	1528	/* The interval intersects with the left interval. */
		1529	return 0;
2087	jermar	1530	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1531	right_cnt * PAGE_SIZE)) {
1387	jermar	1532	/* The interval intersects with the right interval. */
		1533	return 0;
2087	jermar	1534	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1535	(page + count * PAGE_SIZE == right_pg)) {
		1536	/*
		1537	* The interval can be added by merging the two already
		1538	* present intervals.
		1539	* */
1403	jermar	1540	leaf->value[leaf->keys - 1] += count + right_cnt;
1387	jermar	1541	btree_remove(&a->used_space, right_pg, node);
		1542	return 1;
2087	jermar	1543	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1544	/*
		1545	* The interval can be added by simply growing the left
		1546	* interval.
		1547	* */
1403	jermar	1548	leaf->value[leaf->keys - 1] += count;
1387	jermar	1549	return 1;
2087	jermar	1550	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1551	/*
2087	jermar	1552	* The interval can be addded by simply moving base of
		1553	* the right interval down and increasing its size
		1554	* accordingly.
1387	jermar	1555	*/
1403	jermar	1556	node->value[0] += count;
1387	jermar	1557	node->key[0] = page;
		1558	return 1;
		1559	} else {
		1560	/*
		1561	* The interval is between both neigbouring intervals,
		1562	* but cannot be merged with any of them.
		1563	*/
2087	jermar	1564	btree_insert(&a->used_space, page, (void *) count,
		1565	leaf);
1387	jermar	1566	return 1;
		1567	}
		1568	} else if (page >= leaf->key[leaf->keys - 1]) {
1780	jermar	1569	uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387	jermar	1570	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1571
		1572	/*
2087	jermar	1573	* Investigate the border case in which the right neighbour
		1574	* does not exist but the interval fits from the right.
1387	jermar	1575	*/
		1576
2087	jermar	1577	if (overlaps(page, count * PAGE_SIZE, left_pg,
		1578	left_cnt * PAGE_SIZE)) {
1403	jermar	1579	/* The interval intersects with the left interval. */
1387	jermar	1580	return 0;
2087	jermar	1581	} else if (left_pg + left_cnt * PAGE_SIZE == page) {
		1582	/*
		1583	* The interval can be added by growing the left
		1584	* interval.
		1585	*/
1403	jermar	1586	leaf->value[leaf->keys - 1] += count;
1387	jermar	1587	return 1;
		1588	} else {
		1589	/*
		1590	* The interval doesn't adjoin with the left interval.
		1591	* It must be added individually.
		1592	*/
2087	jermar	1593	btree_insert(&a->used_space, page, (void *) count,
		1594	leaf);
1387	jermar	1595	return 1;
		1596	}
		1597	}
		1598
		1599	/*
2087	jermar	1600	* Note that if the algorithm made it thus far, the interval can fit
		1601	* only between two other intervals of the leaf. The two border cases
		1602	* were already resolved.
1387	jermar	1603	*/
		1604	for (i = 1; i < leaf->keys; i++) {
		1605	if (page < leaf->key[i]) {
2087	jermar	1606	uintptr_t left_pg = leaf->key[i - 1];
		1607	uintptr_t right_pg = leaf->key[i];
		1608	count_t left_cnt = (count_t) leaf->value[i - 1];
		1609	count_t right_cnt = (count_t) leaf->value[i];
1387	jermar	1610
		1611	/*
		1612	* The interval fits between left_pg and right_pg.
		1613	*/
		1614
2087	jermar	1615	if (overlaps(page, count * PAGE_SIZE, left_pg,
		1616	left_cnt * PAGE_SIZE)) {
		1617	/*
		1618	* The interval intersects with the left
		1619	* interval.
		1620	*/
1387	jermar	1621	return 0;
2087	jermar	1622	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1623	right_cnt * PAGE_SIZE)) {
		1624	/*
		1625	* The interval intersects with the right
		1626	* interval.
		1627	*/
1387	jermar	1628	return 0;
2087	jermar	1629	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1630	(page + count * PAGE_SIZE == right_pg)) {
		1631	/*
		1632	* The interval can be added by merging the two
		1633	* already present intervals.
		1634	*/
1403	jermar	1635	leaf->value[i - 1] += count + right_cnt;
1387	jermar	1636	btree_remove(&a->used_space, right_pg, leaf);
		1637	return 1;
2087	jermar	1638	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1639	/*
		1640	* The interval can be added by simply growing
		1641	* the left interval.
		1642	*/
1403	jermar	1643	leaf->value[i - 1] += count;
1387	jermar	1644	return 1;
2087	jermar	1645	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1646	/*
2087	jermar	1647	* The interval can be addded by simply moving
		1648	* base of the right interval down and
		1649	* increasing its size accordingly.
1387	jermar	1650	*/
1403	jermar	1651	leaf->value[i] += count;
1387	jermar	1652	leaf->key[i] = page;
		1653	return 1;
		1654	} else {
		1655	/*
2087	jermar	1656	* The interval is between both neigbouring
		1657	* intervals, but cannot be merged with any of
		1658	* them.
1387	jermar	1659	*/
2087	jermar	1660	btree_insert(&a->used_space, page,
		1661	(void *) count, leaf);
1387	jermar	1662	return 1;
		1663	}
		1664	}
		1665	}
		1666
3425	svoboda	1667	panic("Inconsistency detected while adding %" PRIc " pages of used "
4377	svoboda	1668	"space at %p.", count, page);
1387	jermar	1669	}
		1670
		1671	/** Mark portion of address space area as unused.
		1672	*
		1673	* The address space area must be already locked.
		1674	*
3425	svoboda	1675	* @param a Address space area.
		1676	* @param page First page to be marked.
		1677	* @param count Number of page to be marked.
1387	jermar	1678	*
3425	svoboda	1679	* @return Zero on failure and non-zero on success.
1387	jermar	1680	*/
1780	jermar	1681	int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387	jermar	1682	{
		1683	btree_node_t leaf, node;
		1684	count_t pages;
2745	decky	1685	unsigned int i;
1387	jermar	1686
		1687	ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
		1688	ASSERT(count);
		1689
		1690	pages = (count_t) btree_search(&a->used_space, page, &leaf);
		1691	if (pages) {
		1692	/*
		1693	* We are lucky, page is the beginning of some interval.
		1694	*/
		1695	if (count > pages) {
		1696	return 0;
		1697	} else if (count == pages) {
		1698	btree_remove(&a->used_space, page, leaf);
1403	jermar	1699	return 1;
1387	jermar	1700	} else {
		1701	/*
		1702	* Find the respective interval.
		1703	* Decrease its size and relocate its start address.
		1704	*/
		1705	for (i = 0; i < leaf->keys; i++) {
		1706	if (leaf->key[i] == page) {
2087	jermar	1707	leaf->key[i] += count * PAGE_SIZE;
1403	jermar	1708	leaf->value[i] -= count;
1387	jermar	1709	return 1;
		1710	}
		1711	}
		1712	goto error;
		1713	}
		1714	}
		1715
		1716	node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
		1717	if (node && page < leaf->key[0]) {
1780	jermar	1718	uintptr_t left_pg = node->key[node->keys - 1];
1387	jermar	1719	count_t left_cnt = (count_t) node->value[node->keys - 1];
		1720
2087	jermar	1721	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1722	count * PAGE_SIZE)) {
		1723	if (page + count * PAGE_SIZE ==
		1724	left_pg + left_cnt * PAGE_SIZE) {
1387	jermar	1725	/*
2087	jermar	1726	* The interval is contained in the rightmost
		1727	* interval of the left neighbour and can be
		1728	* removed by updating the size of the bigger
		1729	* interval.
1387	jermar	1730	*/
1403	jermar	1731	node->value[node->keys - 1] -= count;
1387	jermar	1732	return 1;
2087	jermar	1733	} else if (page + count * PAGE_SIZE <
		1734	left_pg + left_cnt*PAGE_SIZE) {
1403	jermar	1735	count_t new_cnt;
1387	jermar	1736
		1737	/*
2087	jermar	1738	* The interval is contained in the rightmost
		1739	* interval of the left neighbour but its
		1740	* removal requires both updating the size of
		1741	* the original interval and also inserting a
		1742	* new interval.
1387	jermar	1743	*/
2087	jermar	1744	new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
		1745	(page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403	jermar	1746	node->value[node->keys - 1] -= count + new_cnt;
2087	jermar	1747	btree_insert(&a->used_space, page +
		1748	count * PAGE_SIZE, (void *) new_cnt, leaf);
1387	jermar	1749	return 1;
		1750	}
		1751	}
		1752	return 0;
		1753	} else if (page < leaf->key[0]) {
		1754	return 0;
		1755	}
		1756
		1757	if (page > leaf->key[leaf->keys - 1]) {
1780	jermar	1758	uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387	jermar	1759	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1760
2087	jermar	1761	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1762	count * PAGE_SIZE)) {
		1763	if (page + count * PAGE_SIZE ==
		1764	left_pg + left_cnt * PAGE_SIZE) {
1387	jermar	1765	/*
2087	jermar	1766	* The interval is contained in the rightmost
		1767	* interval of the leaf and can be removed by
		1768	* updating the size of the bigger interval.
1387	jermar	1769	*/
1403	jermar	1770	leaf->value[leaf->keys - 1] -= count;
1387	jermar	1771	return 1;
2087	jermar	1772	} else if (page + count * PAGE_SIZE < left_pg +
		1773	left_cnt * PAGE_SIZE) {
1403	jermar	1774	count_t new_cnt;
1387	jermar	1775
		1776	/*
2087	jermar	1777	* The interval is contained in the rightmost
		1778	* interval of the leaf but its removal
		1779	* requires both updating the size of the
		1780	* original interval and also inserting a new
		1781	* interval.
1387	jermar	1782	*/
2087	jermar	1783	new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
		1784	(page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403	jermar	1785	leaf->value[leaf->keys - 1] -= count + new_cnt;
2087	jermar	1786	btree_insert(&a->used_space, page +
		1787	count * PAGE_SIZE, (void *) new_cnt, leaf);
1387	jermar	1788	return 1;
		1789	}
		1790	}
		1791	return 0;
		1792	}
		1793
		1794	/*
		1795	* The border cases have been already resolved.
		1796	* Now the interval can be only between intervals of the leaf.
		1797	*/
		1798	for (i = 1; i < leaf->keys - 1; i++) {
		1799	if (page < leaf->key[i]) {
1780	jermar	1800	uintptr_t left_pg = leaf->key[i - 1];
1387	jermar	1801	count_t left_cnt = (count_t) leaf->value[i - 1];
		1802
		1803	/*
2087	jermar	1804	* Now the interval is between intervals corresponding
		1805	* to (i - 1) and i.
1387	jermar	1806	*/
2087	jermar	1807	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1808	count * PAGE_SIZE)) {
		1809	if (page + count * PAGE_SIZE ==
		1810	left_pg + left_cnt*PAGE_SIZE) {
1387	jermar	1811	/*
2087	jermar	1812	* The interval is contained in the
		1813	* interval (i - 1) of the leaf and can
		1814	* be removed by updating the size of
		1815	* the bigger interval.
1387	jermar	1816	*/
1403	jermar	1817	leaf->value[i - 1] -= count;
1387	jermar	1818	return 1;
2087	jermar	1819	} else if (page + count * PAGE_SIZE <
		1820	left_pg + left_cnt * PAGE_SIZE) {
1403	jermar	1821	count_t new_cnt;
1387	jermar	1822
		1823	/*
2087	jermar	1824	* The interval is contained in the
		1825	* interval (i - 1) of the leaf but its
		1826	* removal requires both updating the
		1827	* size of the original interval and
1387	jermar	1828	* also inserting a new interval.
		1829	*/
2087	jermar	1830	new_cnt = ((left_pg +
		1831	left_cnt * PAGE_SIZE) -
		1832	(page + count * PAGE_SIZE)) >>
		1833	PAGE_WIDTH;
1403	jermar	1834	leaf->value[i - 1] -= count + new_cnt;
2087	jermar	1835	btree_insert(&a->used_space, page +
		1836	count * PAGE_SIZE, (void *) new_cnt,
		1837	leaf);
1387	jermar	1838	return 1;
		1839	}
		1840	}
		1841	return 0;
		1842	}
		1843	}
		1844
		1845	error:
3425	svoboda	1846	panic("Inconsistency detected while removing %" PRIc " pages of used "
4377	svoboda	1847	"space from %p.", count, page);
1387	jermar	1848	}
		1849
1409	jermar	1850	/** Remove reference to address space area share info.
		1851	*
		1852	* If the reference count drops to 0, the sh_info is deallocated.
		1853	*
3425	svoboda	1854	* @param sh_info Pointer to address space area share info.
1409	jermar	1855	*/
		1856	void sh_info_remove_reference(share_info_t *sh_info)
		1857	{
		1858	bool dealloc = false;
		1859
		1860	mutex_lock(&sh_info->lock);
		1861	ASSERT(sh_info->refcount);
		1862	if (--sh_info->refcount == 0) {
		1863	dealloc = true;
1495	jermar	1864	link_t *cur;
1409	jermar	1865
		1866	/*
		1867	* Now walk carefully the pagemap B+tree and free/remove
		1868	* reference from all frames found there.
		1869	*/
2087	jermar	1870	for (cur = sh_info->pagemap.leaf_head.next;
		1871	cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409	jermar	1872	btree_node_t *node;
2745	decky	1873	unsigned int i;
1409	jermar	1874
1495	jermar	1875	node = list_get_instance(cur, btree_node_t, leaf_link);
		1876	for (i = 0; i < node->keys; i++)
1780	jermar	1877	frame_free((uintptr_t) node->value[i]);
1409	jermar	1878	}
		1879
		1880	}
		1881	mutex_unlock(&sh_info->lock);
		1882
		1883	if (dealloc) {
		1884	btree_destroy(&sh_info->pagemap);
		1885	free(sh_info);
		1886	}
		1887	}
		1888
1235	jermar	1889	/*
		1890	* Address space related syscalls.
		1891	*/
		1892
		1893	/** Wrapper for as_area_create(). */
1780	jermar	1894	unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235	jermar	1895	{
2087	jermar	1896	if (as_area_create(AS, flags \| AS_AREA_CACHEABLE, size, address,
		1897	AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780	jermar	1898	return (unative_t) address;
1235	jermar	1899	else
1780	jermar	1900	return (unative_t) -1;
1235	jermar	1901	}
		1902
1793	jermar	1903	/** Wrapper for as_area_resize(). */
1780	jermar	1904	unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235	jermar	1905	{
1780	jermar	1906	return (unative_t) as_area_resize(AS, address, size, 0);
1235	jermar	1907	}
		1908
3425	svoboda	1909	/** Wrapper for as_area_change_flags(). */
		1910	unative_t sys_as_area_change_flags(uintptr_t address, int flags)
		1911	{
		1912	return (unative_t) as_area_change_flags(AS, flags, address);
		1913	}
		1914
1793	jermar	1915	/** Wrapper for as_area_destroy(). */
1780	jermar	1916	unative_t sys_as_area_destroy(uintptr_t address)
1306	jermar	1917	{
1780	jermar	1918	return (unative_t) as_area_destroy(AS, address);
1306	jermar	1919	}
1702	cejka	1920
1914	jermar	1921	/** Print out information about address space.
		1922	*
3425	svoboda	1923	* @param as Address space.
1914	jermar	1924	*/
		1925	void as_print(as_t *as)
		1926	{
		1927	ipl_t ipl;
		1928
		1929	ipl = interrupts_disable();
		1930	mutex_lock(&as->lock);
		1931
		1932	/* print out info about address space areas */
		1933	link_t *cur;
2087	jermar	1934	for (cur = as->as_area_btree.leaf_head.next;
		1935	cur != &as->as_area_btree.leaf_head; cur = cur->next) {
		1936	btree_node_t *node;
1914	jermar	1937
2087	jermar	1938	node = list_get_instance(cur, btree_node_t, leaf_link);
		1939
2745	decky	1940	unsigned int i;
1914	jermar	1941	for (i = 0; i < node->keys; i++) {
1915	jermar	1942	as_area_t *area = node->value[i];
1914	jermar	1943
		1944	mutex_lock(&area->lock);
3425	svoboda	1945	printf("as_area: %p, base=%p, pages=%" PRIc
		1946	" (%p - %p)\n", area, area->base, area->pages,
		1947	area->base, area->base + FRAMES2SIZE(area->pages));
1914	jermar	1948	mutex_unlock(&area->lock);
		1949	}
		1950	}
		1951
		1952	mutex_unlock(&as->lock);
		1953	interrupts_restore(ipl);
		1954	}
		1955
1757	jermar	1956	/** @}
1702	cejka	1957	*/

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(root)//branches/tracing/kernel/generic/src/mm/as.c – Rev 4377