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

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(root)/branches/tracing/kernel/generic/src/mm/as.c – Rev 3645