WebSVN – HelenOS – Blame – /trunk/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
1235	jermar	114	static int area_flags_to_page_flags(int aflags);
1780	jermar	115	static as_area_t find_area_and_lock(as_t as, uintptr_t va);
2087	jermar	116	static bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
		117	as_area_t *avoid_area);
1409	jermar	118	static void sh_info_remove_reference(share_info_t *sh_info);
703	jermar	119
1891	jermar	120	static int as_constructor(void *obj, int flags)
		121	{
		122	as_t as = (as_t ) obj;
		123	int rc;
		124
		125	link_initialize(&as->inactive_as_with_asid_link);
3186	jermar	126	mutex_initialize(&as->lock, MUTEX_PASSIVE);
1891	jermar	127
		128	rc = as_constructor_arch(as, flags);
		129
		130	return rc;
		131	}
		132
		133	static int as_destructor(void *obj)
		134	{
		135	as_t as = (as_t ) obj;
		136
		137	return as_destructor_arch(as);
		138	}
		139
756	jermar	140	/** Initialize address space subsystem. */
		141	void as_init(void)
		142	{
		143	as_arch_init();
2126	decky	144
1891	jermar	145	as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087	jermar	146	as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
1890	jermar	147
789	palkovsky	148	AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383	decky	149	if (!AS_KERNEL)
		150	panic("can't create kernel address space\n");
		151
756	jermar	152	}
		153
757	jermar	154	/** Create address space.
		155	*
		156	* @param flags Flags that influence way in wich the address space is created.
		157	*/
756	jermar	158	as_t *as_create(int flags)
703	jermar	159	{
		160	as_t *as;
		161
1890	jermar	162	as = (as_t *) slab_alloc(as_slab, 0);
1891	jermar	163	(void) as_create_arch(as, 0);
		164
1147	jermar	165	btree_create(&as->as_area_btree);
822	palkovsky	166
		167	if (flags & FLAG_AS_KERNEL)
		168	as->asid = ASID_KERNEL;
		169	else
		170	as->asid = ASID_INVALID;
		171
2183	jermar	172	atomic_set(&as->refcount, 0);
1415	jermar	173	as->cpu_refcount = 0;
2089	decky	174	#ifdef AS_PAGE_TABLE
2106	jermar	175	as->genarch.page_table = page_table_create(flags);
2089	decky	176	#else
		177	page_table_create(flags);
		178	#endif
703	jermar	179
		180	return as;
		181	}
		182
1468	jermar	183	/** Destroy adress space.
		184	*
2087	jermar	185	* When there are no tasks referencing this address space (i.e. its refcount is
		186	* zero), the address space can be destroyed.
2183	jermar	187	*
		188	* We know that we don't hold any spinlock.
1468	jermar	189	*/
		190	void as_destroy(as_t *as)
973	palkovsky	191	{
1468	jermar	192	ipl_t ipl;
1594	jermar	193	bool cond;
2183	jermar	194	DEADLOCK_PROBE_INIT(p_asidlock);
973	palkovsky	195
2183	jermar	196	ASSERT(atomic_get(&as->refcount) == 0);
1468	jermar	197
		198	/*
		199	* Since there is no reference to this area,
		200	* it is safe not to lock its mutex.
		201	*/
2170	jermar	202
2183	jermar	203	/*
		204	* We need to avoid deadlock between TLB shootdown and asidlock.
		205	* We therefore try to take asid conditionally and if we don't succeed,
		206	* we enable interrupts and try again. This is done while preemption is
		207	* disabled to prevent nested context switches. We also depend on the
		208	* fact that so far no spinlocks are held.
		209	*/
		210	preemption_disable();
		211	ipl = interrupts_read();
		212	retry:
		213	interrupts_disable();
		214	if (!spinlock_trylock(&asidlock)) {
		215	interrupts_enable();
		216	DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
		217	goto retry;
		218	}
		219	preemption_enable(); /* Interrupts disabled, enable preemption */
1587	jermar	220	if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594	jermar	221	if (as != AS && as->cpu_refcount == 0)
1587	jermar	222	list_remove(&as->inactive_as_with_asid_link);
1468	jermar	223	asid_put(as->asid);
		224	}
2170	jermar	225	spinlock_unlock(&asidlock);
1468	jermar	226
		227	/*
		228	* Destroy address space areas of the address space.
1954	jermar	229	* The B+tree must be walked carefully because it is
1594	jermar	230	* also being destroyed.
1468	jermar	231	*/
1594	jermar	232	for (cond = true; cond; ) {
1468	jermar	233	btree_node_t *node;
1594	jermar	234
		235	ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087	jermar	236	node = list_get_instance(as->as_area_btree.leaf_head.next,
		237	btree_node_t, leaf_link);
1594	jermar	238
		239	if ((cond = node->keys)) {
		240	as_area_destroy(as, node->key[0]);
		241	}
1468	jermar	242	}
1495	jermar	243
1483	jermar	244	btree_destroy(&as->as_area_btree);
2089	decky	245	#ifdef AS_PAGE_TABLE
2106	jermar	246	page_table_destroy(as->genarch.page_table);
2089	decky	247	#else
		248	page_table_destroy(NULL);
		249	#endif
1468	jermar	250
		251	interrupts_restore(ipl);
2126	decky	252
1890	jermar	253	slab_free(as_slab, as);
973	palkovsky	254	}
		255
703	jermar	256	/** Create address space area of common attributes.
		257	*
		258	* The created address space area is added to the target address space.
		259	*
		260	* @param as Target address space.
1239	jermar	261	* @param flags Flags of the area memory.
1048	jermar	262	* @param size Size of area.
703	jermar	263	* @param base Base address of area.
1239	jermar	264	* @param attrs Attributes of the area.
1409	jermar	265	* @param backend Address space area backend. NULL if no backend is used.
		266	* @param backend_data NULL or a pointer to an array holding two void *.
703	jermar	267	*
		268	* @return Address space area on success or NULL on failure.
		269	*/
2069	jermar	270	as_area_t *
		271	as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
1424	jermar	272	mem_backend_t backend, mem_backend_data_t backend_data)
703	jermar	273	{
		274	ipl_t ipl;
		275	as_area_t *a;
		276
		277	if (base % PAGE_SIZE)
1048	jermar	278	return NULL;
		279
1233	jermar	280	if (!size)
		281	return NULL;
		282
1048	jermar	283	/* Writeable executable areas are not supported. */
		284	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
		285	return NULL;
703	jermar	286
		287	ipl = interrupts_disable();
1380	jermar	288	mutex_lock(&as->lock);
703	jermar	289
1048	jermar	290	if (!check_area_conflicts(as, base, size, NULL)) {
1380	jermar	291	mutex_unlock(&as->lock);
1048	jermar	292	interrupts_restore(ipl);
		293	return NULL;
		294	}
703	jermar	295
822	palkovsky	296	a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703	jermar	297
3186	jermar	298	mutex_initialize(&a->lock, MUTEX_PASSIVE);
822	palkovsky	299
1424	jermar	300	a->as = as;
1026	jermar	301	a->flags = flags;
1239	jermar	302	a->attributes = attrs;
1048	jermar	303	a->pages = SIZE2FRAMES(size);
822	palkovsky	304	a->base = base;
1409	jermar	305	a->sh_info = NULL;
		306	a->backend = backend;
1424	jermar	307	if (backend_data)
		308	a->backend_data = *backend_data;
		309	else
3104	svoboda	310	memsetb(&a->backend_data, sizeof(a->backend_data), 0);
1424	jermar	311
1387	jermar	312	btree_create(&a->used_space);
822	palkovsky	313
1147	jermar	314	btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822	palkovsky	315
1380	jermar	316	mutex_unlock(&as->lock);
703	jermar	317	interrupts_restore(ipl);
704	jermar	318
703	jermar	319	return a;
		320	}
		321
1235	jermar	322	/** Find address space area and change it.
		323	*
		324	* @param as Address space.
2087	jermar	325	* @param address Virtual address belonging to the area to be changed. Must be
		326	* page-aligned.
1235	jermar	327	* @param size New size of the virtual memory block starting at address.
		328	* @param flags Flags influencing the remap operation. Currently unused.
		329	*
1306	jermar	330	* @return Zero on success or a value from @ref errno.h otherwise.
1235	jermar	331	*/
1780	jermar	332	int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235	jermar	333	{
1306	jermar	334	as_area_t *area;
1235	jermar	335	ipl_t ipl;
		336	size_t pages;
		337
		338	ipl = interrupts_disable();
1380	jermar	339	mutex_lock(&as->lock);
1235	jermar	340
		341	/*
		342	* Locate the area.
		343	*/
		344	area = find_area_and_lock(as, address);
		345	if (!area) {
1380	jermar	346	mutex_unlock(&as->lock);
1235	jermar	347	interrupts_restore(ipl);
1306	jermar	348	return ENOENT;
1235	jermar	349	}
		350
1424	jermar	351	if (area->backend == &phys_backend) {
1235	jermar	352	/*
		353	* Remapping of address space areas associated
		354	* with memory mapped devices is not supported.
		355	*/
1380	jermar	356	mutex_unlock(&area->lock);
		357	mutex_unlock(&as->lock);
1235	jermar	358	interrupts_restore(ipl);
1306	jermar	359	return ENOTSUP;
1235	jermar	360	}
1409	jermar	361	if (area->sh_info) {
		362	/*
		363	* Remapping of shared address space areas
		364	* is not supported.
		365	*/
		366	mutex_unlock(&area->lock);
		367	mutex_unlock(&as->lock);
		368	interrupts_restore(ipl);
		369	return ENOTSUP;
		370	}
1235	jermar	371
		372	pages = SIZE2FRAMES((address - area->base) + size);
		373	if (!pages) {
		374	/*
		375	* Zero size address space areas are not allowed.
		376	*/
1380	jermar	377	mutex_unlock(&area->lock);
		378	mutex_unlock(&as->lock);
1235	jermar	379	interrupts_restore(ipl);
1306	jermar	380	return EPERM;
1235	jermar	381	}
		382
		383	if (pages < area->pages) {
1403	jermar	384	bool cond;
1780	jermar	385	uintptr_t start_free = area->base + pages*PAGE_SIZE;
1235	jermar	386
		387	/*
		388	* Shrinking the area.
		389	* No need to check for overlaps.
		390	*/
1403	jermar	391
		392	/*
1436	jermar	393	* Start TLB shootdown sequence.
		394	*/
2087	jermar	395	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base +
		396	pages * PAGE_SIZE, area->pages - pages);
1436	jermar	397
		398	/*
1403	jermar	399	* Remove frames belonging to used space starting from
		400	* the highest addresses downwards until an overlap with
		401	* the resized address space area is found. Note that this
		402	* is also the right way to remove part of the used_space
		403	* B+tree leaf list.
		404	*/
		405	for (cond = true; cond;) {
		406	btree_node_t *node;
		407
		408	ASSERT(!list_empty(&area->used_space.leaf_head));
2087	jermar	409	node =
		410	list_get_instance(area->used_space.leaf_head.prev,
		411	btree_node_t, leaf_link);
1403	jermar	412	if ((cond = (bool) node->keys)) {
1780	jermar	413	uintptr_t b = node->key[node->keys - 1];
2087	jermar	414	count_t c =
		415	(count_t) node->value[node->keys - 1];
2745	decky	416	unsigned int i = 0;
1235	jermar	417
2087	jermar	418	if (overlaps(b, c * PAGE_SIZE, area->base,
2133	jermar	419	pages * PAGE_SIZE)) {
1403	jermar	420
2087	jermar	421	if (b + c * PAGE_SIZE <= start_free) {
1403	jermar	422	/*
2087	jermar	423	* The whole interval fits
		424	* completely in the resized
		425	* address space area.
1403	jermar	426	*/
		427	break;
		428	}
		429
		430	/*
2087	jermar	431	* Part of the interval corresponding
		432	* to b and c overlaps with the resized
		433	* address space area.
1403	jermar	434	*/
		435
		436	cond = false; /* we are almost done */
		437	i = (start_free - b) >> PAGE_WIDTH;
3057	decky	438	if (!used_space_remove(area, start_free, c - i))
		439	panic("Could not remove used space.\n");
1403	jermar	440	} else {
		441	/*
2087	jermar	442	* The interval of used space can be
		443	* completely removed.
1403	jermar	444	*/
		445	if (!used_space_remove(area, b, c))
3057	decky	446	panic("Could not remove used space.\n");
1403	jermar	447	}
		448
		449	for (; i < c; i++) {
		450	pte_t *pte;
		451
		452	page_table_lock(as, false);
2087	jermar	453	pte = page_mapping_find(as, b +
		454	i * PAGE_SIZE);
		455	ASSERT(pte && PTE_VALID(pte) &&
		456	PTE_PRESENT(pte));
		457	if (area->backend &&
		458	area->backend->frame_free) {
1424	jermar	459	area->backend->frame_free(area,
2087	jermar	460	b + i * PAGE_SIZE,
		461	PTE_GET_FRAME(pte));
1409	jermar	462	}
2087	jermar	463	page_mapping_remove(as, b +
		464	i * PAGE_SIZE);
1403	jermar	465	page_table_unlock(as, false);
		466	}
1235	jermar	467	}
		468	}
1436	jermar	469
1235	jermar	470	/*
1436	jermar	471	* Finish TLB shootdown sequence.
1235	jermar	472	*/
2183	jermar	473
2087	jermar	474	tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
		475	area->pages - pages);
1889	jermar	476	/*
		477	* Invalidate software translation caches (e.g. TSB on sparc64).
		478	*/
2087	jermar	479	as_invalidate_translation_cache(as, area->base +
		480	pages * PAGE_SIZE, area->pages - pages);
2183	jermar	481	tlb_shootdown_finalize();
		482
1235	jermar	483	} else {
		484	/*
		485	* Growing the area.
		486	* Check for overlaps with other address space areas.
		487	*/
2087	jermar	488	if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
		489	area)) {
1380	jermar	490	mutex_unlock(&area->lock);
		491	mutex_unlock(&as->lock);
1235	jermar	492	interrupts_restore(ipl);
1306	jermar	493	return EADDRNOTAVAIL;
1235	jermar	494	}
		495	}
		496
		497	area->pages = pages;
		498
1380	jermar	499	mutex_unlock(&area->lock);
		500	mutex_unlock(&as->lock);
1235	jermar	501	interrupts_restore(ipl);
		502
1306	jermar	503	return 0;
1235	jermar	504	}
		505
1306	jermar	506	/** Destroy address space area.
		507	*
		508	* @param as Address space.
		509	* @param address Address withing the area to be deleted.
		510	*
		511	* @return Zero on success or a value from @ref errno.h on failure.
		512	*/
1780	jermar	513	int as_area_destroy(as_t *as, uintptr_t address)
1306	jermar	514	{
		515	as_area_t *area;
1780	jermar	516	uintptr_t base;
1495	jermar	517	link_t *cur;
1306	jermar	518	ipl_t ipl;
		519
		520	ipl = interrupts_disable();
1380	jermar	521	mutex_lock(&as->lock);
1306	jermar	522
		523	area = find_area_and_lock(as, address);
		524	if (!area) {
1380	jermar	525	mutex_unlock(&as->lock);
1306	jermar	526	interrupts_restore(ipl);
		527	return ENOENT;
		528	}
		529
1403	jermar	530	base = area->base;
		531
1411	jermar	532	/*
1436	jermar	533	* Start TLB shootdown sequence.
		534	*/
1889	jermar	535	tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436	jermar	536
		537	/*
1411	jermar	538	* Visit only the pages mapped by used_space B+tree.
		539	*/
2087	jermar	540	for (cur = area->used_space.leaf_head.next;
		541	cur != &area->used_space.leaf_head; cur = cur->next) {
1411	jermar	542	btree_node_t *node;
2745	decky	543	unsigned int i;
1403	jermar	544
1495	jermar	545	node = list_get_instance(cur, btree_node_t, leaf_link);
		546	for (i = 0; i < node->keys; i++) {
1780	jermar	547	uintptr_t b = node->key[i];
1495	jermar	548	count_t j;
1411	jermar	549	pte_t *pte;
1403	jermar	550
1495	jermar	551	for (j = 0; j < (count_t) node->value[i]; j++) {
1411	jermar	552	page_table_lock(as, false);
2087	jermar	553	pte = page_mapping_find(as, b + j * PAGE_SIZE);
		554	ASSERT(pte && PTE_VALID(pte) &&
		555	PTE_PRESENT(pte));
		556	if (area->backend &&
		557	area->backend->frame_free) {
		558	area->backend->frame_free(area, b +
2133	jermar	559	j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403	jermar	560	}
2087	jermar	561	page_mapping_remove(as, b + j * PAGE_SIZE);
1411	jermar	562	page_table_unlock(as, false);
1306	jermar	563	}
		564	}
		565	}
1403	jermar	566
1306	jermar	567	/*
1436	jermar	568	* Finish TLB shootdown sequence.
1306	jermar	569	*/
2183	jermar	570
1889	jermar	571	tlb_invalidate_pages(as->asid, area->base, area->pages);
		572	/*
2087	jermar	573	* Invalidate potential software translation caches (e.g. TSB on
		574	* sparc64).
1889	jermar	575	*/
		576	as_invalidate_translation_cache(as, area->base, area->pages);
2183	jermar	577	tlb_shootdown_finalize();
1889	jermar	578
1436	jermar	579	btree_destroy(&area->used_space);
1306	jermar	580
1309	jermar	581	area->attributes \|= AS_AREA_ATTR_PARTIAL;
1409	jermar	582
		583	if (area->sh_info)
		584	sh_info_remove_reference(area->sh_info);
		585
1380	jermar	586	mutex_unlock(&area->lock);
1306	jermar	587
		588	/*
		589	* Remove the empty area from address space.
		590	*/
1889	jermar	591	btree_remove(&as->as_area_btree, base, NULL);
1306	jermar	592
1309	jermar	593	free(area);
		594
1889	jermar	595	mutex_unlock(&as->lock);
1306	jermar	596	interrupts_restore(ipl);
		597	return 0;
		598	}
		599
1413	jermar	600	/** Share address space area with another or the same address space.
1235	jermar	601	*
1424	jermar	602	* Address space area mapping is shared with a new address space area.
		603	* If the source address space area has not been shared so far,
		604	* a new sh_info is created. The new address space area simply gets the
		605	* sh_info of the source area. The process of duplicating the
		606	* mapping is done through the backend share function.
1413	jermar	607	*
1417	jermar	608	* @param src_as Pointer to source address space.
1239	jermar	609	* @param src_base Base address of the source address space area.
1417	jermar	610	* @param acc_size Expected size of the source area.
1428	palkovsky	611	* @param dst_as Pointer to destination address space.
1417	jermar	612	* @param dst_base Target base address.
		613	* @param dst_flags_mask Destination address space area flags mask.
1235	jermar	614	*
2007	jermar	615	* @return Zero on success or ENOENT if there is no such task or if there is no
		616	* such address space area, EPERM if there was a problem in accepting the area
		617	* or ENOMEM if there was a problem in allocating destination address space
		618	* area. ENOTSUP is returned if the address space area backend does not support
2141	jermar	619	* sharing.
1235	jermar	620	*/
1780	jermar	621	int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647	jermar	622	as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235	jermar	623	{
		624	ipl_t ipl;
1239	jermar	625	int src_flags;
		626	size_t src_size;
		627	as_area_t src_area, dst_area;
1413	jermar	628	share_info_t *sh_info;
1424	jermar	629	mem_backend_t *src_backend;
		630	mem_backend_data_t src_backend_data;
1434	palkovsky	631
1235	jermar	632	ipl = interrupts_disable();
1380	jermar	633	mutex_lock(&src_as->lock);
1329	palkovsky	634	src_area = find_area_and_lock(src_as, src_base);
1239	jermar	635	if (!src_area) {
1238	jermar	636	/*
		637	* Could not find the source address space area.
		638	*/
1380	jermar	639	mutex_unlock(&src_as->lock);
1238	jermar	640	interrupts_restore(ipl);
		641	return ENOENT;
		642	}
2007	jermar	643
1424	jermar	644	if (!src_area->backend \|\| !src_area->backend->share) {
1413	jermar	645	/*
1851	jermar	646	* There is no backend or the backend does not
1424	jermar	647	* know how to share the area.
1413	jermar	648	*/
		649	mutex_unlock(&src_area->lock);
		650	mutex_unlock(&src_as->lock);
		651	interrupts_restore(ipl);
		652	return ENOTSUP;
		653	}
		654
1239	jermar	655	src_size = src_area->pages * PAGE_SIZE;
		656	src_flags = src_area->flags;
1424	jermar	657	src_backend = src_area->backend;
		658	src_backend_data = src_area->backend_data;
1544	palkovsky	659
		660	/* Share the cacheable flag from the original mapping */
		661	if (src_flags & AS_AREA_CACHEABLE)
		662	dst_flags_mask \|= AS_AREA_CACHEABLE;
		663
2087	jermar	664	if (src_size != acc_size \|\|
		665	(src_flags & dst_flags_mask) != dst_flags_mask) {
1413	jermar	666	mutex_unlock(&src_area->lock);
		667	mutex_unlock(&src_as->lock);
1235	jermar	668	interrupts_restore(ipl);
		669	return EPERM;
		670	}
1413	jermar	671
1235	jermar	672	/*
1413	jermar	673	* Now we are committed to sharing the area.
1954	jermar	674	* First, prepare the area for sharing.
1413	jermar	675	* Then it will be safe to unlock it.
		676	*/
		677	sh_info = src_area->sh_info;
		678	if (!sh_info) {
		679	sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
3186	jermar	680	mutex_initialize(&sh_info->lock, MUTEX_PASSIVE);
1413	jermar	681	sh_info->refcount = 2;
		682	btree_create(&sh_info->pagemap);
		683	src_area->sh_info = sh_info;
2647	jermar	684	/*
		685	* Call the backend to setup sharing.
		686	*/
		687	src_area->backend->share(src_area);
1413	jermar	688	} else {
		689	mutex_lock(&sh_info->lock);
		690	sh_info->refcount++;
		691	mutex_unlock(&sh_info->lock);
		692	}
		693
		694	mutex_unlock(&src_area->lock);
		695	mutex_unlock(&src_as->lock);
		696
		697	/*
1239	jermar	698	* Create copy of the source address space area.
		699	* The destination area is created with AS_AREA_ATTR_PARTIAL
		700	* attribute set which prevents race condition with
		701	* preliminary as_page_fault() calls.
1417	jermar	702	* The flags of the source area are masked against dst_flags_mask
		703	* to support sharing in less privileged mode.
1235	jermar	704	*/
1461	palkovsky	705	dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087	jermar	706	AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239	jermar	707	if (!dst_area) {
1235	jermar	708	/*
		709	* Destination address space area could not be created.
		710	*/
1413	jermar	711	sh_info_remove_reference(sh_info);
		712
1235	jermar	713	interrupts_restore(ipl);
		714	return ENOMEM;
		715	}
2009	jermar	716
1235	jermar	717	/*
1239	jermar	718	* Now the destination address space area has been
		719	* fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413	jermar	720	* attribute and set the sh_info.
1239	jermar	721	*/
2009	jermar	722	mutex_lock(&dst_as->lock);
1380	jermar	723	mutex_lock(&dst_area->lock);
1239	jermar	724	dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413	jermar	725	dst_area->sh_info = sh_info;
1380	jermar	726	mutex_unlock(&dst_area->lock);
2009	jermar	727	mutex_unlock(&dst_as->lock);
		728
1235	jermar	729	interrupts_restore(ipl);
		730
		731	return 0;
		732	}
		733
1423	jermar	734	/** Check access mode for address space area.
		735	*
		736	* The address space area must be locked prior to this call.
		737	*
		738	* @param area Address space area.
		739	* @param access Access mode.
		740	*
		741	* @return False if access violates area's permissions, true otherwise.
		742	*/
		743	bool as_area_check_access(as_area_t *area, pf_access_t access)
		744	{
		745	int flagmap[] = {
		746	[PF_ACCESS_READ] = AS_AREA_READ,
		747	[PF_ACCESS_WRITE] = AS_AREA_WRITE,
		748	[PF_ACCESS_EXEC] = AS_AREA_EXEC
		749	};
		750
		751	if (!(area->flags & flagmap[access]))
		752	return false;
		753
		754	return true;
		755	}
		756
3222	svoboda	757	/** Change adress area flags.
		758	*
		759	* The idea is to have the same data, but with a different access mode.
		760	* This is needed e.g. for writing code into memory and then executing it.
		761	* In order for this to work properly, this may copy the data
		762	* into private anonymous memory (unless it's already there).
		763	*
		764	* @param as Address space.
		765	* @param flags Flags of the area memory.
		766	* @param address Address withing the area to be changed.
		767	*
		768	* @return Zero on success or a value from @ref errno.h on failure.
		769	*/
		770	int as_area_change_flags(as_t *as, int flags, uintptr_t address)
		771	{
		772	as_area_t *area;
		773	uintptr_t base;
		774	link_t *cur;
		775	ipl_t ipl;
		776	int page_flags;
		777	uintptr_t *old_frame;
		778	index_t frame_idx;
		779	count_t used_pages;
		780
		781	/* Flags for the new memory mapping */
		782	page_flags = area_flags_to_page_flags(flags);
		783
		784	ipl = interrupts_disable();
		785	mutex_lock(&as->lock);
		786
		787	area = find_area_and_lock(as, address);
		788	if (!area) {
		789	mutex_unlock(&as->lock);
		790	interrupts_restore(ipl);
		791	return ENOENT;
		792	}
		793
		794	if (area->sh_info \|\| area->backend != &anon_backend) {
		795	/* Copying shared areas not supported yet */
		796	/* Copying non-anonymous memory not supported yet */
		797	mutex_unlock(&area->lock);
		798	mutex_unlock(&as->lock);
		799	interrupts_restore(ipl);
		800	return ENOTSUP;
		801	}
		802
		803	base = area->base;
		804
		805	/*
		806	* Compute total number of used pages in the used_space B+tree
		807	*/
		808	used_pages = 0;
		809
		810	for (cur = area->used_space.leaf_head.next;
		811	cur != &area->used_space.leaf_head; cur = cur->next) {
		812	btree_node_t *node;
		813	unsigned int i;
		814
		815	node = list_get_instance(cur, btree_node_t, leaf_link);
		816	for (i = 0; i < node->keys; i++) {
		817	used_pages += (count_t) node->value[i];
		818	}
		819	}
		820
		821	/* An array for storing frame numbers */
		822	old_frame = malloc(used_pages * sizeof(uintptr_t), 0);
		823
		824	/*
		825	* Start TLB shootdown sequence.
		826	*/
		827	tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
		828
		829	/*
		830	* Remove used pages from page tables and remember their frame
		831	* numbers.
		832	*/
		833	frame_idx = 0;
		834
		835	for (cur = area->used_space.leaf_head.next;
		836	cur != &area->used_space.leaf_head; cur = cur->next) {
		837	btree_node_t *node;
		838	unsigned int i;
		839
		840	node = list_get_instance(cur, btree_node_t, leaf_link);
		841	for (i = 0; i < node->keys; i++) {
		842	uintptr_t b = node->key[i];
		843	count_t j;
		844	pte_t *pte;
		845
		846	for (j = 0; j < (count_t) node->value[i]; j++) {
		847	page_table_lock(as, false);
		848	pte = page_mapping_find(as, b + j * PAGE_SIZE);
		849	ASSERT(pte && PTE_VALID(pte) &&
		850	PTE_PRESENT(pte));
		851	old_frame[frame_idx++] = PTE_GET_FRAME(pte);
		852
		853	/* Remove old mapping */
		854	page_mapping_remove(as, b + j * PAGE_SIZE);
		855	page_table_unlock(as, false);
		856	}
		857	}
		858	}
		859
		860	/*
		861	* Finish TLB shootdown sequence.
		862	*/
		863
		864	tlb_invalidate_pages(as->asid, area->base, area->pages);
		865	/*
		866	* Invalidate potential software translation caches (e.g. TSB on
		867	* sparc64).
		868	*/
		869	as_invalidate_translation_cache(as, area->base, area->pages);
		870	tlb_shootdown_finalize();
		871
		872	/*
3383	svoboda	873	* Set the new flags.
		874	*/
		875	area->flags = flags;
		876
		877	/*
3222	svoboda	878	* Map pages back in with new flags. This step is kept separate
		879	* so that there's no instant when the memory area could be
		880	* accesed with both the old and the new flags at once.
		881	*/
		882	frame_idx = 0;
		883
		884	for (cur = area->used_space.leaf_head.next;
		885	cur != &area->used_space.leaf_head; cur = cur->next) {
		886	btree_node_t *node;
		887	unsigned int i;
		888
		889	node = list_get_instance(cur, btree_node_t, leaf_link);
		890	for (i = 0; i < node->keys; i++) {
		891	uintptr_t b = node->key[i];
		892	count_t j;
		893
		894	for (j = 0; j < (count_t) node->value[i]; j++) {
		895	page_table_lock(as, false);
		896
		897	/* Insert the new mapping */
		898	page_mapping_insert(as, b + j * PAGE_SIZE,
		899	old_frame[frame_idx++], page_flags);
		900
		901	page_table_unlock(as, false);
		902	}
		903	}
		904	}
		905
		906	free(old_frame);
		907
		908	mutex_unlock(&area->lock);
		909	mutex_unlock(&as->lock);
		910	interrupts_restore(ipl);
		911
		912	return 0;
		913	}
		914
		915
703	jermar	916	/** Handle page fault within the current address space.
		917	*
1409	jermar	918	* This is the high-level page fault handler. It decides
		919	* whether the page fault can be resolved by any backend
		920	* and if so, it invokes the backend to resolve the page
		921	* fault.
		922	*
703	jermar	923	* Interrupts are assumed disabled.
		924	*
		925	* @param page Faulting page.
1411	jermar	926	* @param access Access mode that caused the fault (i.e. read/write/exec).
1288	jermar	927	* @param istate Pointer to interrupted state.
703	jermar	928	*
1409	jermar	929	* @return AS_PF_FAULT on page fault, AS_PF_OK on success or AS_PF_DEFER if the
		930	* fault was caused by copy_to_uspace() or copy_from_uspace().
703	jermar	931	*/
1780	jermar	932	int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703	jermar	933	{
1044	jermar	934	pte_t *pte;
977	jermar	935	as_area_t *area;
703	jermar	936
1380	jermar	937	if (!THREAD)
1409	jermar	938	return AS_PF_FAULT;
1380	jermar	939
703	jermar	940	ASSERT(AS);
1044	jermar	941
1380	jermar	942	mutex_lock(&AS->lock);
977	jermar	943	area = find_area_and_lock(AS, page);
703	jermar	944	if (!area) {
		945	/*
		946	* No area contained mapping for 'page'.
		947	* Signal page fault to low-level handler.
		948	*/
1380	jermar	949	mutex_unlock(&AS->lock);
1288	jermar	950	goto page_fault;
703	jermar	951	}
		952
1239	jermar	953	if (area->attributes & AS_AREA_ATTR_PARTIAL) {
		954	/*
		955	* The address space area is not fully initialized.
		956	* Avoid possible race by returning error.
		957	*/
1380	jermar	958	mutex_unlock(&area->lock);
		959	mutex_unlock(&AS->lock);
1288	jermar	960	goto page_fault;
1239	jermar	961	}
		962
1424	jermar	963	if (!area->backend \|\| !area->backend->page_fault) {
1409	jermar	964	/*
		965	* The address space area is not backed by any backend
		966	* or the backend cannot handle page faults.
		967	*/
		968	mutex_unlock(&area->lock);
		969	mutex_unlock(&AS->lock);
		970	goto page_fault;
		971	}
1179	jermar	972
1044	jermar	973	page_table_lock(AS, false);
		974
703	jermar	975	/*
1044	jermar	976	* To avoid race condition between two page faults
		977	* on the same address, we need to make sure
		978	* the mapping has not been already inserted.
		979	*/
		980	if ((pte = page_mapping_find(AS, page))) {
		981	if (PTE_PRESENT(pte)) {
1423	jermar	982	if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) \|\|
2087	jermar	983	(access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) \|\|
		984	(access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423	jermar	985	page_table_unlock(AS, false);
		986	mutex_unlock(&area->lock);
		987	mutex_unlock(&AS->lock);
		988	return AS_PF_OK;
		989	}
1044	jermar	990	}
		991	}
1409	jermar	992
1044	jermar	993	/*
1409	jermar	994	* Resort to the backend page fault handler.
703	jermar	995	*/
1424	jermar	996	if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409	jermar	997	page_table_unlock(AS, false);
		998	mutex_unlock(&area->lock);
		999	mutex_unlock(&AS->lock);
		1000	goto page_fault;
		1001	}
703	jermar	1002
1044	jermar	1003	page_table_unlock(AS, false);
1380	jermar	1004	mutex_unlock(&area->lock);
		1005	mutex_unlock(&AS->lock);
1288	jermar	1006	return AS_PF_OK;
		1007
		1008	page_fault:
		1009	if (THREAD->in_copy_from_uspace) {
		1010	THREAD->in_copy_from_uspace = false;
2087	jermar	1011	istate_set_retaddr(istate,
		1012	(uintptr_t) &memcpy_from_uspace_failover_address);
1288	jermar	1013	} else if (THREAD->in_copy_to_uspace) {
		1014	THREAD->in_copy_to_uspace = false;
2087	jermar	1015	istate_set_retaddr(istate,
		1016	(uintptr_t) &memcpy_to_uspace_failover_address);
1288	jermar	1017	} else {
		1018	return AS_PF_FAULT;
		1019	}
		1020
		1021	return AS_PF_DEFER;
703	jermar	1022	}
		1023
823	jermar	1024	/** Switch address spaces.
703	jermar	1025	*
1380	jermar	1026	* Note that this function cannot sleep as it is essentially a part of
2170	jermar	1027	* scheduling. Sleeping here would lead to deadlock on wakeup. Another
		1028	* thing which is forbidden in this context is locking the address space.
1380	jermar	1029	*
2183	jermar	1030	* When this function is enetered, no spinlocks may be held.
		1031	*
823	jermar	1032	* @param old Old address space or NULL.
		1033	* @param new New address space.
703	jermar	1034	*/
2106	jermar	1035	void as_switch(as_t old_as, as_t new_as)
703	jermar	1036	{
2183	jermar	1037	DEADLOCK_PROBE_INIT(p_asidlock);
		1038	preemption_disable();
		1039	retry:
		1040	(void) interrupts_disable();
		1041	if (!spinlock_trylock(&asidlock)) {
		1042	/*
		1043	* Avoid deadlock with TLB shootdown.
		1044	* We can enable interrupts here because
		1045	* preemption is disabled. We should not be
		1046	* holding any other lock.
		1047	*/
		1048	(void) interrupts_enable();
		1049	DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
		1050	goto retry;
		1051	}
		1052	preemption_enable();
703	jermar	1053
		1054	/*
823	jermar	1055	* First, take care of the old address space.
		1056	*/
2106	jermar	1057	if (old_as) {
		1058	ASSERT(old_as->cpu_refcount);
		1059	if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823	jermar	1060	/*
		1061	* The old address space is no longer active on
		1062	* any processor. It can be appended to the
		1063	* list of inactive address spaces with assigned
		1064	* ASID.
		1065	*/
2141	jermar	1066	ASSERT(old_as->asid != ASID_INVALID);
		1067	list_append(&old_as->inactive_as_with_asid_link,
		1068	&inactive_as_with_asid_head);
823	jermar	1069	}
1890	jermar	1070
		1071	/*
		1072	* Perform architecture-specific tasks when the address space
		1073	* is being removed from the CPU.
		1074	*/
2106	jermar	1075	as_deinstall_arch(old_as);
823	jermar	1076	}
		1077
		1078	/*
		1079	* Second, prepare the new address space.
		1080	*/
2106	jermar	1081	if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170	jermar	1082	if (new_as->asid != ASID_INVALID)
2106	jermar	1083	list_remove(&new_as->inactive_as_with_asid_link);
2170	jermar	1084	else
		1085	new_as->asid = asid_get();
823	jermar	1086	}
2106	jermar	1087	#ifdef AS_PAGE_TABLE
		1088	SET_PTL0_ADDRESS(new_as->genarch.page_table);
		1089	#endif
823	jermar	1090
		1091	/*
703	jermar	1092	* Perform architecture-specific steps.
727	jermar	1093	* (e.g. write ASID to hardware register etc.)
703	jermar	1094	*/
2106	jermar	1095	as_install_arch(new_as);
2170	jermar	1096
		1097	spinlock_unlock(&asidlock);
703	jermar	1098
2106	jermar	1099	AS = new_as;
703	jermar	1100	}
754	jermar	1101
1235	jermar	1102	/** Convert address space area flags to page flags.
754	jermar	1103	*
1235	jermar	1104	* @param aflags Flags of some address space area.
754	jermar	1105	*
1235	jermar	1106	* @return Flags to be passed to page_mapping_insert().
754	jermar	1107	*/
1235	jermar	1108	int area_flags_to_page_flags(int aflags)
754	jermar	1109	{
		1110	int flags;
		1111
1178	jermar	1112	flags = PAGE_USER \| PAGE_PRESENT;
754	jermar	1113
1235	jermar	1114	if (aflags & AS_AREA_READ)
1026	jermar	1115	flags \|= PAGE_READ;
		1116
1235	jermar	1117	if (aflags & AS_AREA_WRITE)
1026	jermar	1118	flags \|= PAGE_WRITE;
		1119
1235	jermar	1120	if (aflags & AS_AREA_EXEC)
1026	jermar	1121	flags \|= PAGE_EXEC;
		1122
1424	jermar	1123	if (aflags & AS_AREA_CACHEABLE)
1178	jermar	1124	flags \|= PAGE_CACHEABLE;
		1125
754	jermar	1126	return flags;
		1127	}
756	jermar	1128
1235	jermar	1129	/** Compute flags for virtual address translation subsytem.
		1130	*
		1131	* The address space area must be locked.
		1132	* Interrupts must be disabled.
		1133	*
		1134	* @param a Address space area.
		1135	*
		1136	* @return Flags to be used in page_mapping_insert().
		1137	*/
1409	jermar	1138	int as_area_get_flags(as_area_t *a)
1235	jermar	1139	{
		1140	return area_flags_to_page_flags(a->flags);
		1141	}
		1142
756	jermar	1143	/** Create page table.
		1144	*
		1145	* Depending on architecture, create either address space
		1146	* private or global page table.
		1147	*
		1148	* @param flags Flags saying whether the page table is for kernel address space.
		1149	*
		1150	* @return First entry of the page table.
		1151	*/
		1152	pte_t *page_table_create(int flags)
		1153	{
2125	decky	1154	ASSERT(as_operations);
		1155	ASSERT(as_operations->page_table_create);
		1156
		1157	return as_operations->page_table_create(flags);
756	jermar	1158	}
977	jermar	1159
1468	jermar	1160	/** Destroy page table.
		1161	*
		1162	* Destroy page table in architecture specific way.
		1163	*
		1164	* @param page_table Physical address of PTL0.
		1165	*/
		1166	void page_table_destroy(pte_t *page_table)
		1167	{
2125	decky	1168	ASSERT(as_operations);
		1169	ASSERT(as_operations->page_table_destroy);
		1170
		1171	as_operations->page_table_destroy(page_table);
1468	jermar	1172	}
		1173
1044	jermar	1174	/** Lock page table.
		1175	*
		1176	* This function should be called before any page_mapping_insert(),
		1177	* page_mapping_remove() and page_mapping_find().
		1178	*
		1179	* Locking order is such that address space areas must be locked
		1180	* prior to this call. Address space can be locked prior to this
		1181	* call in which case the lock argument is false.
		1182	*
		1183	* @param as Address space.
1248	jermar	1184	* @param lock If false, do not attempt to lock as->lock.
1044	jermar	1185	*/
		1186	void page_table_lock(as_t *as, bool lock)
		1187	{
		1188	ASSERT(as_operations);
		1189	ASSERT(as_operations->page_table_lock);
2125	decky	1190
1044	jermar	1191	as_operations->page_table_lock(as, lock);
		1192	}
		1193
		1194	/** Unlock page table.
		1195	*
		1196	* @param as Address space.
1248	jermar	1197	* @param unlock If false, do not attempt to unlock as->lock.
1044	jermar	1198	*/
		1199	void page_table_unlock(as_t *as, bool unlock)
		1200	{
		1201	ASSERT(as_operations);
		1202	ASSERT(as_operations->page_table_unlock);
2125	decky	1203
1044	jermar	1204	as_operations->page_table_unlock(as, unlock);
		1205	}
		1206
977	jermar	1207
		1208	/** Find address space area and lock it.
		1209	*
		1210	* The address space must be locked and interrupts must be disabled.
		1211	*
		1212	* @param as Address space.
		1213	* @param va Virtual address.
		1214	*
2087	jermar	1215	* @return Locked address space area containing va on success or NULL on
		1216	* failure.
977	jermar	1217	*/
1780	jermar	1218	as_area_t find_area_and_lock(as_t as, uintptr_t va)
977	jermar	1219	{
		1220	as_area_t *a;
1147	jermar	1221	btree_node_t leaf, lnode;
2745	decky	1222	unsigned int i;
977	jermar	1223
1147	jermar	1224	a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
		1225	if (a) {
		1226	/* va is the base address of an address space area */
1380	jermar	1227	mutex_lock(&a->lock);
1147	jermar	1228	return a;
		1229	}
		1230
		1231	/*
1150	jermar	1232	* Search the leaf node and the righmost record of its left neighbour
1147	jermar	1233	* to find out whether this is a miss or va belongs to an address
		1234	* space area found there.
		1235	*/
		1236
		1237	/* First, search the leaf node itself. */
		1238	for (i = 0; i < leaf->keys; i++) {
		1239	a = (as_area_t *) leaf->value[i];
1380	jermar	1240	mutex_lock(&a->lock);
1147	jermar	1241	if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
		1242	return a;
		1243	}
1380	jermar	1244	mutex_unlock(&a->lock);
1147	jermar	1245	}
977	jermar	1246
1147	jermar	1247	/*
1150	jermar	1248	* Second, locate the left neighbour and test its last record.
1148	jermar	1249	* Because of its position in the B+tree, it must have base < va.
1147	jermar	1250	*/
2087	jermar	1251	lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
		1252	if (lnode) {
1147	jermar	1253	a = (as_area_t *) lnode->value[lnode->keys - 1];
1380	jermar	1254	mutex_lock(&a->lock);
1147	jermar	1255	if (va < a->base + a->pages * PAGE_SIZE) {
1048	jermar	1256	return a;
1147	jermar	1257	}
1380	jermar	1258	mutex_unlock(&a->lock);
977	jermar	1259	}
		1260
		1261	return NULL;
		1262	}
1048	jermar	1263
		1264	/** Check area conflicts with other areas.
		1265	*
		1266	* The address space must be locked and interrupts must be disabled.
		1267	*
		1268	* @param as Address space.
		1269	* @param va Starting virtual address of the area being tested.
		1270	* @param size Size of the area being tested.
		1271	* @param avoid_area Do not touch this area.
		1272	*
		1273	* @return True if there is no conflict, false otherwise.
		1274	*/
2087	jermar	1275	bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
		1276	as_area_t *avoid_area)
1048	jermar	1277	{
		1278	as_area_t *a;
1147	jermar	1279	btree_node_t leaf, node;
2745	decky	1280	unsigned int i;
1048	jermar	1281
1070	jermar	1282	/*
		1283	* We don't want any area to have conflicts with NULL page.
		1284	*/
		1285	if (overlaps(va, size, NULL, PAGE_SIZE))
		1286	return false;
		1287
1147	jermar	1288	/*
		1289	* The leaf node is found in O(log n), where n is proportional to
		1290	* the number of address space areas belonging to as.
		1291	* The check for conflicts is then attempted on the rightmost
1150	jermar	1292	* record in the left neighbour, the leftmost record in the right
		1293	* neighbour and all records in the leaf node itself.
1147	jermar	1294	*/
1048	jermar	1295
1147	jermar	1296	if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
		1297	if (a != avoid_area)
		1298	return false;
		1299	}
		1300
		1301	/* First, check the two border cases. */
1150	jermar	1302	if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147	jermar	1303	a = (as_area_t *) node->value[node->keys - 1];
1380	jermar	1304	mutex_lock(&a->lock);
1147	jermar	1305	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1306	mutex_unlock(&a->lock);
1147	jermar	1307	return false;
		1308	}
1380	jermar	1309	mutex_unlock(&a->lock);
1147	jermar	1310	}
2087	jermar	1311	node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
		1312	if (node) {
1147	jermar	1313	a = (as_area_t *) node->value[0];
1380	jermar	1314	mutex_lock(&a->lock);
1147	jermar	1315	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1316	mutex_unlock(&a->lock);
1147	jermar	1317	return false;
		1318	}
1380	jermar	1319	mutex_unlock(&a->lock);
1147	jermar	1320	}
		1321
		1322	/* Second, check the leaf node. */
		1323	for (i = 0; i < leaf->keys; i++) {
		1324	a = (as_area_t *) leaf->value[i];
		1325
1048	jermar	1326	if (a == avoid_area)
		1327	continue;
1147	jermar	1328
1380	jermar	1329	mutex_lock(&a->lock);
1147	jermar	1330	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1331	mutex_unlock(&a->lock);
1147	jermar	1332	return false;
		1333	}
1380	jermar	1334	mutex_unlock(&a->lock);
1048	jermar	1335	}
		1336
1070	jermar	1337	/*
		1338	* So far, the area does not conflict with other areas.
		1339	* Check if it doesn't conflict with kernel address space.
		1340	*/
		1341	if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
		1342	return !overlaps(va, size,
2087	jermar	1343	KERNEL_ADDRESS_SPACE_START,
		1344	KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070	jermar	1345	}
		1346
1048	jermar	1347	return true;
		1348	}
1235	jermar	1349
2556	jermar	1350	/** Return size of the address space area with given base.
		1351	*
		1352	* @param base Arbitrary address insede the address space area.
		1353	*
		1354	* @return Size of the address space area in bytes or zero if it
		1355	* does not exist.
		1356	*/
		1357	size_t as_area_get_size(uintptr_t base)
1329	palkovsky	1358	{
		1359	ipl_t ipl;
		1360	as_area_t *src_area;
		1361	size_t size;
		1362
		1363	ipl = interrupts_disable();
		1364	src_area = find_area_and_lock(AS, base);
		1365	if (src_area){
		1366	size = src_area->pages * PAGE_SIZE;
1380	jermar	1367	mutex_unlock(&src_area->lock);
1329	palkovsky	1368	} else {
		1369	size = 0;
		1370	}
		1371	interrupts_restore(ipl);
		1372	return size;
		1373	}
		1374
1387	jermar	1375	/** Mark portion of address space area as used.
		1376	*
		1377	* The address space area must be already locked.
		1378	*
		1379	* @param a Address space area.
		1380	* @param page First page to be marked.
		1381	* @param count Number of page to be marked.
		1382	*
		1383	* @return 0 on failure and 1 on success.
		1384	*/
1780	jermar	1385	int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387	jermar	1386	{
		1387	btree_node_t leaf, node;
		1388	count_t pages;
2745	decky	1389	unsigned int i;
1387	jermar	1390
		1391	ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
		1392	ASSERT(count);
		1393
		1394	pages = (count_t) btree_search(&a->used_space, page, &leaf);
		1395	if (pages) {
		1396	/*
		1397	* We hit the beginning of some used space.
		1398	*/
		1399	return 0;
		1400	}
		1401
1437	jermar	1402	if (!leaf->keys) {
		1403	btree_insert(&a->used_space, page, (void *) count, leaf);
		1404	return 1;
		1405	}
		1406
1387	jermar	1407	node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
		1408	if (node) {
2087	jermar	1409	uintptr_t left_pg = node->key[node->keys - 1];
		1410	uintptr_t right_pg = leaf->key[0];
		1411	count_t left_cnt = (count_t) node->value[node->keys - 1];
		1412	count_t right_cnt = (count_t) leaf->value[0];
1387	jermar	1413
		1414	/*
		1415	* Examine the possibility that the interval fits
		1416	* somewhere between the rightmost interval of
		1417	* the left neigbour and the first interval of the leaf.
		1418	*/
		1419
		1420	if (page >= right_pg) {
		1421	/* Do nothing. */
2087	jermar	1422	} else if (overlaps(page, count * PAGE_SIZE, left_pg,
		1423	left_cnt * PAGE_SIZE)) {
1387	jermar	1424	/* The interval intersects with the left interval. */
		1425	return 0;
2087	jermar	1426	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1427	right_cnt * PAGE_SIZE)) {
1387	jermar	1428	/* The interval intersects with the right interval. */
		1429	return 0;
2087	jermar	1430	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1431	(page + count * PAGE_SIZE == right_pg)) {
		1432	/*
		1433	* The interval can be added by merging the two already
		1434	* present intervals.
		1435	*/
1403	jermar	1436	node->value[node->keys - 1] += count + right_cnt;
1387	jermar	1437	btree_remove(&a->used_space, right_pg, leaf);
		1438	return 1;
2087	jermar	1439	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1440	/*
		1441	* The interval can be added by simply growing the left
		1442	* interval.
		1443	*/
1403	jermar	1444	node->value[node->keys - 1] += count;
1387	jermar	1445	return 1;
2087	jermar	1446	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1447	/*
2087	jermar	1448	* The interval can be addded by simply moving base of
		1449	* the right interval down and increasing its size
		1450	* accordingly.
1387	jermar	1451	*/
1403	jermar	1452	leaf->value[0] += count;
1387	jermar	1453	leaf->key[0] = page;
		1454	return 1;
		1455	} else {
		1456	/*
		1457	* The interval is between both neigbouring intervals,
		1458	* but cannot be merged with any of them.
		1459	*/
2087	jermar	1460	btree_insert(&a->used_space, page, (void *) count,
		1461	leaf);
1387	jermar	1462	return 1;
		1463	}
		1464	} else if (page < leaf->key[0]) {
1780	jermar	1465	uintptr_t right_pg = leaf->key[0];
1387	jermar	1466	count_t right_cnt = (count_t) leaf->value[0];
		1467
		1468	/*
2087	jermar	1469	* Investigate the border case in which the left neighbour does
		1470	* not exist but the interval fits from the left.
1387	jermar	1471	*/
		1472
2087	jermar	1473	if (overlaps(page, count * PAGE_SIZE, right_pg,
		1474	right_cnt * PAGE_SIZE)) {
1387	jermar	1475	/* The interval intersects with the right interval. */
		1476	return 0;
2087	jermar	1477	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1478	/*
2087	jermar	1479	* The interval can be added by moving the base of the
		1480	* right interval down and increasing its size
		1481	* accordingly.
1387	jermar	1482	*/
		1483	leaf->key[0] = page;
1403	jermar	1484	leaf->value[0] += count;
1387	jermar	1485	return 1;
		1486	} else {
		1487	/*
		1488	* The interval doesn't adjoin with the right interval.
		1489	* It must be added individually.
		1490	*/
2087	jermar	1491	btree_insert(&a->used_space, page, (void *) count,
		1492	leaf);
1387	jermar	1493	return 1;
		1494	}
		1495	}
		1496
		1497	node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
		1498	if (node) {
2087	jermar	1499	uintptr_t left_pg = leaf->key[leaf->keys - 1];
		1500	uintptr_t right_pg = node->key[0];
		1501	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1502	count_t right_cnt = (count_t) node->value[0];
1387	jermar	1503
		1504	/*
		1505	* Examine the possibility that the interval fits
		1506	* somewhere between the leftmost interval of
		1507	* the right neigbour and the last interval of the leaf.
		1508	*/
		1509
		1510	if (page < left_pg) {
		1511	/* Do nothing. */
2087	jermar	1512	} else if (overlaps(page, count * PAGE_SIZE, left_pg,
		1513	left_cnt * PAGE_SIZE)) {
1387	jermar	1514	/* The interval intersects with the left interval. */
		1515	return 0;
2087	jermar	1516	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1517	right_cnt * PAGE_SIZE)) {
1387	jermar	1518	/* The interval intersects with the right interval. */
		1519	return 0;
2087	jermar	1520	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1521	(page + count * PAGE_SIZE == right_pg)) {
		1522	/*
		1523	* The interval can be added by merging the two already
		1524	* present intervals.
		1525	* */
1403	jermar	1526	leaf->value[leaf->keys - 1] += count + right_cnt;
1387	jermar	1527	btree_remove(&a->used_space, right_pg, node);
		1528	return 1;
2087	jermar	1529	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1530	/*
		1531	* The interval can be added by simply growing the left
		1532	* interval.
		1533	* */
1403	jermar	1534	leaf->value[leaf->keys - 1] += count;
1387	jermar	1535	return 1;
2087	jermar	1536	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1537	/*
2087	jermar	1538	* The interval can be addded by simply moving base of
		1539	* the right interval down and increasing its size
		1540	* accordingly.
1387	jermar	1541	*/
1403	jermar	1542	node->value[0] += count;
1387	jermar	1543	node->key[0] = page;
		1544	return 1;
		1545	} else {
		1546	/*
		1547	* The interval is between both neigbouring intervals,
		1548	* but cannot be merged with any of them.
		1549	*/
2087	jermar	1550	btree_insert(&a->used_space, page, (void *) count,
		1551	leaf);
1387	jermar	1552	return 1;
		1553	}
		1554	} else if (page >= leaf->key[leaf->keys - 1]) {
1780	jermar	1555	uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387	jermar	1556	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1557
		1558	/*
2087	jermar	1559	* Investigate the border case in which the right neighbour
		1560	* does not exist but the interval fits from the right.
1387	jermar	1561	*/
		1562
2087	jermar	1563	if (overlaps(page, count * PAGE_SIZE, left_pg,
		1564	left_cnt * PAGE_SIZE)) {
1403	jermar	1565	/* The interval intersects with the left interval. */
1387	jermar	1566	return 0;
2087	jermar	1567	} else if (left_pg + left_cnt * PAGE_SIZE == page) {
		1568	/*
		1569	* The interval can be added by growing the left
		1570	* interval.
		1571	*/
1403	jermar	1572	leaf->value[leaf->keys - 1] += count;
1387	jermar	1573	return 1;
		1574	} else {
		1575	/*
		1576	* The interval doesn't adjoin with the left interval.
		1577	* It must be added individually.
		1578	*/
2087	jermar	1579	btree_insert(&a->used_space, page, (void *) count,
		1580	leaf);
1387	jermar	1581	return 1;
		1582	}
		1583	}
		1584
		1585	/*
2087	jermar	1586	* Note that if the algorithm made it thus far, the interval can fit
		1587	* only between two other intervals of the leaf. The two border cases
		1588	* were already resolved.
1387	jermar	1589	*/
		1590	for (i = 1; i < leaf->keys; i++) {
		1591	if (page < leaf->key[i]) {
2087	jermar	1592	uintptr_t left_pg = leaf->key[i - 1];
		1593	uintptr_t right_pg = leaf->key[i];
		1594	count_t left_cnt = (count_t) leaf->value[i - 1];
		1595	count_t right_cnt = (count_t) leaf->value[i];
1387	jermar	1596
		1597	/*
		1598	* The interval fits between left_pg and right_pg.
		1599	*/
		1600
2087	jermar	1601	if (overlaps(page, count * PAGE_SIZE, left_pg,
		1602	left_cnt * PAGE_SIZE)) {
		1603	/*
		1604	* The interval intersects with the left
		1605	* interval.
		1606	*/
1387	jermar	1607	return 0;
2087	jermar	1608	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1609	right_cnt * PAGE_SIZE)) {
		1610	/*
		1611	* The interval intersects with the right
		1612	* interval.
		1613	*/
1387	jermar	1614	return 0;
2087	jermar	1615	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1616	(page + count * PAGE_SIZE == right_pg)) {
		1617	/*
		1618	* The interval can be added by merging the two
		1619	* already present intervals.
		1620	*/
1403	jermar	1621	leaf->value[i - 1] += count + right_cnt;
1387	jermar	1622	btree_remove(&a->used_space, right_pg, leaf);
		1623	return 1;
2087	jermar	1624	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1625	/*
		1626	* The interval can be added by simply growing
		1627	* the left interval.
		1628	*/
1403	jermar	1629	leaf->value[i - 1] += count;
1387	jermar	1630	return 1;
2087	jermar	1631	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1632	/*
2087	jermar	1633	* The interval can be addded by simply moving
		1634	* base of the right interval down and
		1635	* increasing its size accordingly.
1387	jermar	1636	*/
1403	jermar	1637	leaf->value[i] += count;
1387	jermar	1638	leaf->key[i] = page;
		1639	return 1;
		1640	} else {
		1641	/*
2087	jermar	1642	* The interval is between both neigbouring
		1643	* intervals, but cannot be merged with any of
		1644	* them.
1387	jermar	1645	*/
2087	jermar	1646	btree_insert(&a->used_space, page,
		1647	(void *) count, leaf);
1387	jermar	1648	return 1;
		1649	}
		1650	}
		1651	}
		1652
3057	decky	1653	panic("Inconsistency detected while adding %" PRIc " pages of used space at "
2087	jermar	1654	"%p.\n", count, page);
1387	jermar	1655	}
		1656
		1657	/** Mark portion of address space area as unused.
		1658	*
		1659	* The address space area must be already locked.
		1660	*
		1661	* @param a Address space area.
		1662	* @param page First page to be marked.
		1663	* @param count Number of page to be marked.
		1664	*
		1665	* @return 0 on failure and 1 on success.
		1666	*/
1780	jermar	1667	int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387	jermar	1668	{
		1669	btree_node_t leaf, node;
		1670	count_t pages;
2745	decky	1671	unsigned int i;
1387	jermar	1672
		1673	ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
		1674	ASSERT(count);
		1675
		1676	pages = (count_t) btree_search(&a->used_space, page, &leaf);
		1677	if (pages) {
		1678	/*
		1679	* We are lucky, page is the beginning of some interval.
		1680	*/
		1681	if (count > pages) {
		1682	return 0;
		1683	} else if (count == pages) {
		1684	btree_remove(&a->used_space, page, leaf);
1403	jermar	1685	return 1;
1387	jermar	1686	} else {
		1687	/*
		1688	* Find the respective interval.
		1689	* Decrease its size and relocate its start address.
		1690	*/
		1691	for (i = 0; i < leaf->keys; i++) {
		1692	if (leaf->key[i] == page) {
2087	jermar	1693	leaf->key[i] += count * PAGE_SIZE;
1403	jermar	1694	leaf->value[i] -= count;
1387	jermar	1695	return 1;
		1696	}
		1697	}
		1698	goto error;
		1699	}
		1700	}
		1701
		1702	node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
		1703	if (node && page < leaf->key[0]) {
1780	jermar	1704	uintptr_t left_pg = node->key[node->keys - 1];
1387	jermar	1705	count_t left_cnt = (count_t) node->value[node->keys - 1];
		1706
2087	jermar	1707	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1708	count * PAGE_SIZE)) {
		1709	if (page + count * PAGE_SIZE ==
		1710	left_pg + left_cnt * PAGE_SIZE) {
1387	jermar	1711	/*
2087	jermar	1712	* The interval is contained in the rightmost
		1713	* interval of the left neighbour and can be
		1714	* removed by updating the size of the bigger
		1715	* interval.
1387	jermar	1716	*/
1403	jermar	1717	node->value[node->keys - 1] -= count;
1387	jermar	1718	return 1;
2087	jermar	1719	} else if (page + count * PAGE_SIZE <
		1720	left_pg + left_cnt*PAGE_SIZE) {
1403	jermar	1721	count_t new_cnt;
1387	jermar	1722
		1723	/*
2087	jermar	1724	* The interval is contained in the rightmost
		1725	* interval of the left neighbour but its
		1726	* removal requires both updating the size of
		1727	* the original interval and also inserting a
		1728	* new interval.
1387	jermar	1729	*/
2087	jermar	1730	new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
		1731	(page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403	jermar	1732	node->value[node->keys - 1] -= count + new_cnt;
2087	jermar	1733	btree_insert(&a->used_space, page +
		1734	count * PAGE_SIZE, (void *) new_cnt, leaf);
1387	jermar	1735	return 1;
		1736	}
		1737	}
		1738	return 0;
		1739	} else if (page < leaf->key[0]) {
		1740	return 0;
		1741	}
		1742
		1743	if (page > leaf->key[leaf->keys - 1]) {
1780	jermar	1744	uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387	jermar	1745	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1746
2087	jermar	1747	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1748	count * PAGE_SIZE)) {
		1749	if (page + count * PAGE_SIZE ==
		1750	left_pg + left_cnt * PAGE_SIZE) {
1387	jermar	1751	/*
2087	jermar	1752	* The interval is contained in the rightmost
		1753	* interval of the leaf and can be removed by
		1754	* updating the size of the bigger interval.
1387	jermar	1755	*/
1403	jermar	1756	leaf->value[leaf->keys - 1] -= count;
1387	jermar	1757	return 1;
2087	jermar	1758	} else if (page + count * PAGE_SIZE < left_pg +
		1759	left_cnt * PAGE_SIZE) {
1403	jermar	1760	count_t new_cnt;
1387	jermar	1761
		1762	/*
2087	jermar	1763	* The interval is contained in the rightmost
		1764	* interval of the leaf but its removal
		1765	* requires both updating the size of the
		1766	* original interval and also inserting a new
		1767	* interval.
1387	jermar	1768	*/
2087	jermar	1769	new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
		1770	(page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403	jermar	1771	leaf->value[leaf->keys - 1] -= count + new_cnt;
2087	jermar	1772	btree_insert(&a->used_space, page +
		1773	count * PAGE_SIZE, (void *) new_cnt, leaf);
1387	jermar	1774	return 1;
		1775	}
		1776	}
		1777	return 0;
		1778	}
		1779
		1780	/*
		1781	* The border cases have been already resolved.
		1782	* Now the interval can be only between intervals of the leaf.
		1783	*/
		1784	for (i = 1; i < leaf->keys - 1; i++) {
		1785	if (page < leaf->key[i]) {
1780	jermar	1786	uintptr_t left_pg = leaf->key[i - 1];
1387	jermar	1787	count_t left_cnt = (count_t) leaf->value[i - 1];
		1788
		1789	/*
2087	jermar	1790	* Now the interval is between intervals corresponding
		1791	* to (i - 1) and i.
1387	jermar	1792	*/
2087	jermar	1793	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1794	count * PAGE_SIZE)) {
		1795	if (page + count * PAGE_SIZE ==
		1796	left_pg + left_cnt*PAGE_SIZE) {
1387	jermar	1797	/*
2087	jermar	1798	* The interval is contained in the
		1799	* interval (i - 1) of the leaf and can
		1800	* be removed by updating the size of
		1801	* the bigger interval.
1387	jermar	1802	*/
1403	jermar	1803	leaf->value[i - 1] -= count;
1387	jermar	1804	return 1;
2087	jermar	1805	} else if (page + count * PAGE_SIZE <
		1806	left_pg + left_cnt * PAGE_SIZE) {
1403	jermar	1807	count_t new_cnt;
1387	jermar	1808
		1809	/*
2087	jermar	1810	* The interval is contained in the
		1811	* interval (i - 1) of the leaf but its
		1812	* removal requires both updating the
		1813	* size of the original interval and
1387	jermar	1814	* also inserting a new interval.
		1815	*/
2087	jermar	1816	new_cnt = ((left_pg +
		1817	left_cnt * PAGE_SIZE) -
		1818	(page + count * PAGE_SIZE)) >>
		1819	PAGE_WIDTH;
1403	jermar	1820	leaf->value[i - 1] -= count + new_cnt;
2087	jermar	1821	btree_insert(&a->used_space, page +
		1822	count * PAGE_SIZE, (void *) new_cnt,
		1823	leaf);
1387	jermar	1824	return 1;
		1825	}
		1826	}
		1827	return 0;
		1828	}
		1829	}
		1830
		1831	error:
3057	decky	1832	panic("Inconsistency detected while removing %" PRIc " pages of used space "
2087	jermar	1833	"from %p.\n", count, page);
1387	jermar	1834	}
		1835
1409	jermar	1836	/** Remove reference to address space area share info.
		1837	*
		1838	* If the reference count drops to 0, the sh_info is deallocated.
		1839	*
		1840	* @param sh_info Pointer to address space area share info.
		1841	*/
		1842	void sh_info_remove_reference(share_info_t *sh_info)
		1843	{
		1844	bool dealloc = false;
		1845
		1846	mutex_lock(&sh_info->lock);
		1847	ASSERT(sh_info->refcount);
		1848	if (--sh_info->refcount == 0) {
		1849	dealloc = true;
1495	jermar	1850	link_t *cur;
1409	jermar	1851
		1852	/*
		1853	* Now walk carefully the pagemap B+tree and free/remove
		1854	* reference from all frames found there.
		1855	*/
2087	jermar	1856	for (cur = sh_info->pagemap.leaf_head.next;
		1857	cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409	jermar	1858	btree_node_t *node;
2745	decky	1859	unsigned int i;
1409	jermar	1860
1495	jermar	1861	node = list_get_instance(cur, btree_node_t, leaf_link);
		1862	for (i = 0; i < node->keys; i++)
1780	jermar	1863	frame_free((uintptr_t) node->value[i]);
1409	jermar	1864	}
		1865
		1866	}
		1867	mutex_unlock(&sh_info->lock);
		1868
		1869	if (dealloc) {
		1870	btree_destroy(&sh_info->pagemap);
		1871	free(sh_info);
		1872	}
		1873	}
		1874
1235	jermar	1875	/*
		1876	* Address space related syscalls.
		1877	*/
		1878
		1879	/** Wrapper for as_area_create(). */
1780	jermar	1880	unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235	jermar	1881	{
2087	jermar	1882	if (as_area_create(AS, flags \| AS_AREA_CACHEABLE, size, address,
		1883	AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780	jermar	1884	return (unative_t) address;
1235	jermar	1885	else
1780	jermar	1886	return (unative_t) -1;
1235	jermar	1887	}
		1888
1793	jermar	1889	/** Wrapper for as_area_resize(). */
1780	jermar	1890	unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235	jermar	1891	{
1780	jermar	1892	return (unative_t) as_area_resize(AS, address, size, 0);
1235	jermar	1893	}
		1894
3222	svoboda	1895	/** Wrapper for as_area_change_flags(). */
		1896	unative_t sys_as_area_change_flags(uintptr_t address, int flags)
		1897	{
		1898	return (unative_t) as_area_change_flags(AS, flags, address);
		1899	}
		1900
1793	jermar	1901	/** Wrapper for as_area_destroy(). */
1780	jermar	1902	unative_t sys_as_area_destroy(uintptr_t address)
1306	jermar	1903	{
1780	jermar	1904	return (unative_t) as_area_destroy(AS, address);
1306	jermar	1905	}
1702	cejka	1906
1914	jermar	1907	/** Print out information about address space.
		1908	*
		1909	* @param as Address space.
		1910	*/
		1911	void as_print(as_t *as)
		1912	{
		1913	ipl_t ipl;
		1914
		1915	ipl = interrupts_disable();
		1916	mutex_lock(&as->lock);
		1917
		1918	/* print out info about address space areas */
		1919	link_t *cur;
2087	jermar	1920	for (cur = as->as_area_btree.leaf_head.next;
		1921	cur != &as->as_area_btree.leaf_head; cur = cur->next) {
		1922	btree_node_t *node;
1914	jermar	1923
2087	jermar	1924	node = list_get_instance(cur, btree_node_t, leaf_link);
		1925
2745	decky	1926	unsigned int i;
1914	jermar	1927	for (i = 0; i < node->keys; i++) {
1915	jermar	1928	as_area_t *area = node->value[i];
1914	jermar	1929
		1930	mutex_lock(&area->lock);
3057	decky	1931	printf("as_area: %p, base=%p, pages=%" PRIc " (%p - %p)\n",
2087	jermar	1932	area, area->base, area->pages, area->base,
3057	decky	1933	area->base + FRAMES2SIZE(area->pages));
1914	jermar	1934	mutex_unlock(&area->lock);
		1935	}
		1936	}
		1937
		1938	mutex_unlock(&as->lock);
		1939	interrupts_restore(ipl);
		1940	}
		1941
1757	jermar	1942	/** @}
1702	cejka	1943	*/

Subversion Repositories HelenOS

(root)/trunk/kernel/generic/src/mm/as.c – Rev 3383