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
2125	decky	85	#ifndef __OBJC__
1757	jermar	86	/**
		87	* Each architecture decides what functions will be used to carry out
		88	* address space operations such as creating or locking page tables.
		89	*/
756	jermar	90	as_operations_t *as_operations = NULL;
703	jermar	91
1890	jermar	92	/**
		93	* Slab for as_t objects.
		94	*/
		95	static slab_cache_t *as_slab;
2126	decky	96	#endif
1890	jermar	97
2087	jermar	98	/**
2170	jermar	99	* This lock serializes access to the ASID subsystem.
		100	* It protects:
		101	* - inactive_as_with_asid_head list
		102	* - as->asid for each as of the as_t type
		103	* - asids_allocated counter
2087	jermar	104	*/
2170	jermar	105	SPINLOCK_INITIALIZE(asidlock);
823	jermar	106
		107	/**
		108	* This list contains address spaces that are not active on any
		109	* processor and that have valid ASID.
		110	*/
		111	LIST_INITIALIZE(inactive_as_with_asid_head);
		112
757	jermar	113	/** Kernel address space. */
		114	as_t *AS_KERNEL = NULL;
		115
1235	jermar	116	static int area_flags_to_page_flags(int aflags);
1780	jermar	117	static as_area_t find_area_and_lock(as_t as, uintptr_t va);
2087	jermar	118	static bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
		119	as_area_t *avoid_area);
1409	jermar	120	static void sh_info_remove_reference(share_info_t *sh_info);
703	jermar	121
2126	decky	122	#ifndef __OBJC__
1891	jermar	123	static int as_constructor(void *obj, int flags)
		124	{
		125	as_t as = (as_t ) obj;
		126	int rc;
		127
		128	link_initialize(&as->inactive_as_with_asid_link);
		129	mutex_initialize(&as->lock);
		130
		131	rc = as_constructor_arch(as, flags);
		132
		133	return rc;
		134	}
		135
		136	static int as_destructor(void *obj)
		137	{
		138	as_t as = (as_t ) obj;
		139
		140	return as_destructor_arch(as);
		141	}
2126	decky	142	#endif
1891	jermar	143
756	jermar	144	/** Initialize address space subsystem. */
		145	void as_init(void)
		146	{
		147	as_arch_init();
2126	decky	148
		149	#ifndef __OBJC__
1891	jermar	150	as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087	jermar	151	as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
2126	decky	152	#endif
1890	jermar	153
789	palkovsky	154	AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383	decky	155	if (!AS_KERNEL)
		156	panic("can't create kernel address space\n");
		157
756	jermar	158	}
		159
757	jermar	160	/** Create address space.
		161	*
		162	* @param flags Flags that influence way in wich the address space is created.
		163	*/
756	jermar	164	as_t *as_create(int flags)
703	jermar	165	{
		166	as_t *as;
		167
2126	decky	168	#ifdef __OBJC__
		169	as = [as_t new];
		170	link_initialize(&as->inactive_as_with_asid_link);
		171	mutex_initialize(&as->lock);
		172	(void) as_constructor_arch(as, flags);
		173	#else
1890	jermar	174	as = (as_t *) slab_alloc(as_slab, 0);
2126	decky	175	#endif
1891	jermar	176	(void) as_create_arch(as, 0);
		177
1147	jermar	178	btree_create(&as->as_area_btree);
822	palkovsky	179
		180	if (flags & FLAG_AS_KERNEL)
		181	as->asid = ASID_KERNEL;
		182	else
		183	as->asid = ASID_INVALID;
		184
2183	jermar	185	atomic_set(&as->refcount, 0);
1415	jermar	186	as->cpu_refcount = 0;
2089	decky	187	#ifdef AS_PAGE_TABLE
2106	jermar	188	as->genarch.page_table = page_table_create(flags);
2089	decky	189	#else
		190	page_table_create(flags);
		191	#endif
703	jermar	192
		193	return as;
		194	}
		195
1468	jermar	196	/** Destroy adress space.
		197	*
2087	jermar	198	* When there are no tasks referencing this address space (i.e. its refcount is
		199	* zero), the address space can be destroyed.
2183	jermar	200	*
		201	* We know that we don't hold any spinlock.
1468	jermar	202	*/
		203	void as_destroy(as_t *as)
973	palkovsky	204	{
1468	jermar	205	ipl_t ipl;
1594	jermar	206	bool cond;
2183	jermar	207	DEADLOCK_PROBE_INIT(p_asidlock);
973	palkovsky	208
2183	jermar	209	ASSERT(atomic_get(&as->refcount) == 0);
1468	jermar	210
		211	/*
		212	* Since there is no reference to this area,
		213	* it is safe not to lock its mutex.
		214	*/
2170	jermar	215
2183	jermar	216	/*
		217	* We need to avoid deadlock between TLB shootdown and asidlock.
		218	* We therefore try to take asid conditionally and if we don't succeed,
		219	* we enable interrupts and try again. This is done while preemption is
		220	* disabled to prevent nested context switches. We also depend on the
		221	* fact that so far no spinlocks are held.
		222	*/
		223	preemption_disable();
		224	ipl = interrupts_read();
		225	retry:
		226	interrupts_disable();
		227	if (!spinlock_trylock(&asidlock)) {
		228	interrupts_enable();
		229	DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
		230	goto retry;
		231	}
		232	preemption_enable(); /* Interrupts disabled, enable preemption */
1587	jermar	233	if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594	jermar	234	if (as != AS && as->cpu_refcount == 0)
1587	jermar	235	list_remove(&as->inactive_as_with_asid_link);
1468	jermar	236	asid_put(as->asid);
		237	}
2170	jermar	238	spinlock_unlock(&asidlock);
1468	jermar	239
		240	/*
		241	* Destroy address space areas of the address space.
1954	jermar	242	* The B+tree must be walked carefully because it is
1594	jermar	243	* also being destroyed.
1468	jermar	244	*/
1594	jermar	245	for (cond = true; cond; ) {
1468	jermar	246	btree_node_t *node;
1594	jermar	247
		248	ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087	jermar	249	node = list_get_instance(as->as_area_btree.leaf_head.next,
		250	btree_node_t, leaf_link);
1594	jermar	251
		252	if ((cond = node->keys)) {
		253	as_area_destroy(as, node->key[0]);
		254	}
1468	jermar	255	}
1495	jermar	256
1483	jermar	257	btree_destroy(&as->as_area_btree);
2089	decky	258	#ifdef AS_PAGE_TABLE
2106	jermar	259	page_table_destroy(as->genarch.page_table);
2089	decky	260	#else
		261	page_table_destroy(NULL);
		262	#endif
1468	jermar	263
		264	interrupts_restore(ipl);
2126	decky	265
		266	#ifdef __OBJC__
		267	[as free];
		268	#else
1890	jermar	269	slab_free(as_slab, as);
2126	decky	270	#endif
973	palkovsky	271	}
		272
703	jermar	273	/** Create address space area of common attributes.
		274	*
		275	* The created address space area is added to the target address space.
		276	*
		277	* @param as Target address space.
1239	jermar	278	* @param flags Flags of the area memory.
1048	jermar	279	* @param size Size of area.
703	jermar	280	* @param base Base address of area.
1239	jermar	281	* @param attrs Attributes of the area.
1409	jermar	282	* @param backend Address space area backend. NULL if no backend is used.
		283	* @param backend_data NULL or a pointer to an array holding two void *.
703	jermar	284	*
		285	* @return Address space area on success or NULL on failure.
		286	*/
2069	jermar	287	as_area_t *
		288	as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
1424	jermar	289	mem_backend_t backend, mem_backend_data_t backend_data)
703	jermar	290	{
		291	ipl_t ipl;
		292	as_area_t *a;
		293
		294	if (base % PAGE_SIZE)
1048	jermar	295	return NULL;
		296
1233	jermar	297	if (!size)
		298	return NULL;
		299
1048	jermar	300	/* Writeable executable areas are not supported. */
		301	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
		302	return NULL;
703	jermar	303
		304	ipl = interrupts_disable();
1380	jermar	305	mutex_lock(&as->lock);
703	jermar	306
1048	jermar	307	if (!check_area_conflicts(as, base, size, NULL)) {
1380	jermar	308	mutex_unlock(&as->lock);
1048	jermar	309	interrupts_restore(ipl);
		310	return NULL;
		311	}
703	jermar	312
822	palkovsky	313	a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703	jermar	314
1380	jermar	315	mutex_initialize(&a->lock);
822	palkovsky	316
1424	jermar	317	a->as = as;
1026	jermar	318	a->flags = flags;
1239	jermar	319	a->attributes = attrs;
1048	jermar	320	a->pages = SIZE2FRAMES(size);
822	palkovsky	321	a->base = base;
1409	jermar	322	a->sh_info = NULL;
		323	a->backend = backend;
1424	jermar	324	if (backend_data)
		325	a->backend_data = *backend_data;
		326	else
3424	svoboda	327	memsetb(&a->backend_data, sizeof(a->backend_data), 0);
1424	jermar	328
1387	jermar	329	btree_create(&a->used_space);
822	palkovsky	330
1147	jermar	331	btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822	palkovsky	332
1380	jermar	333	mutex_unlock(&as->lock);
703	jermar	334	interrupts_restore(ipl);
704	jermar	335
703	jermar	336	return a;
		337	}
		338
1235	jermar	339	/** Find address space area and change it.
		340	*
		341	* @param as Address space.
2087	jermar	342	* @param address Virtual address belonging to the area to be changed. Must be
		343	* page-aligned.
1235	jermar	344	* @param size New size of the virtual memory block starting at address.
		345	* @param flags Flags influencing the remap operation. Currently unused.
		346	*
1306	jermar	347	* @return Zero on success or a value from @ref errno.h otherwise.
1235	jermar	348	*/
1780	jermar	349	int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235	jermar	350	{
1306	jermar	351	as_area_t *area;
1235	jermar	352	ipl_t ipl;
		353	size_t pages;
		354
		355	ipl = interrupts_disable();
1380	jermar	356	mutex_lock(&as->lock);
1235	jermar	357
		358	/*
		359	* Locate the area.
		360	*/
		361	area = find_area_and_lock(as, address);
		362	if (!area) {
1380	jermar	363	mutex_unlock(&as->lock);
1235	jermar	364	interrupts_restore(ipl);
1306	jermar	365	return ENOENT;
1235	jermar	366	}
		367
1424	jermar	368	if (area->backend == &phys_backend) {
1235	jermar	369	/*
		370	* Remapping of address space areas associated
		371	* with memory mapped devices is not supported.
		372	*/
1380	jermar	373	mutex_unlock(&area->lock);
		374	mutex_unlock(&as->lock);
1235	jermar	375	interrupts_restore(ipl);
1306	jermar	376	return ENOTSUP;
1235	jermar	377	}
1409	jermar	378	if (area->sh_info) {
		379	/*
		380	* Remapping of shared address space areas
		381	* is not supported.
		382	*/
		383	mutex_unlock(&area->lock);
		384	mutex_unlock(&as->lock);
		385	interrupts_restore(ipl);
		386	return ENOTSUP;
		387	}
1235	jermar	388
		389	pages = SIZE2FRAMES((address - area->base) + size);
		390	if (!pages) {
		391	/*
		392	* Zero size address space areas are not allowed.
		393	*/
1380	jermar	394	mutex_unlock(&area->lock);
		395	mutex_unlock(&as->lock);
1235	jermar	396	interrupts_restore(ipl);
1306	jermar	397	return EPERM;
1235	jermar	398	}
		399
		400	if (pages < area->pages) {
1403	jermar	401	bool cond;
1780	jermar	402	uintptr_t start_free = area->base + pages*PAGE_SIZE;
1235	jermar	403
		404	/*
		405	* Shrinking the area.
		406	* No need to check for overlaps.
		407	*/
1403	jermar	408
		409	/*
1436	jermar	410	* Start TLB shootdown sequence.
		411	*/
2087	jermar	412	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base +
		413	pages * PAGE_SIZE, area->pages - pages);
1436	jermar	414
		415	/*
1403	jermar	416	* Remove frames belonging to used space starting from
		417	* the highest addresses downwards until an overlap with
		418	* the resized address space area is found. Note that this
		419	* is also the right way to remove part of the used_space
		420	* B+tree leaf list.
		421	*/
		422	for (cond = true; cond;) {
		423	btree_node_t *node;
		424
		425	ASSERT(!list_empty(&area->used_space.leaf_head));
2087	jermar	426	node =
		427	list_get_instance(area->used_space.leaf_head.prev,
		428	btree_node_t, leaf_link);
1403	jermar	429	if ((cond = (bool) node->keys)) {
1780	jermar	430	uintptr_t b = node->key[node->keys - 1];
2087	jermar	431	count_t c =
		432	(count_t) node->value[node->keys - 1];
2745	decky	433	unsigned int i = 0;
1235	jermar	434
2087	jermar	435	if (overlaps(b, c * PAGE_SIZE, area->base,
2133	jermar	436	pages * PAGE_SIZE)) {
1403	jermar	437
2087	jermar	438	if (b + c * PAGE_SIZE <= start_free) {
1403	jermar	439	/*
2087	jermar	440	* The whole interval fits
		441	* completely in the resized
		442	* address space area.
1403	jermar	443	*/
		444	break;
		445	}
		446
		447	/*
2087	jermar	448	* Part of the interval corresponding
		449	* to b and c overlaps with the resized
		450	* address space area.
1403	jermar	451	*/
		452
		453	cond = false; /* we are almost done */
		454	i = (start_free - b) >> PAGE_WIDTH;
3424	svoboda	455	if (!used_space_remove(area, start_free, c - i))
		456	panic("Could not remove used space.\n");
1403	jermar	457	} else {
		458	/*
2087	jermar	459	* The interval of used space can be
		460	* completely removed.
1403	jermar	461	*/
		462	if (!used_space_remove(area, b, c))
3424	svoboda	463	panic("Could not remove used space.\n");
1403	jermar	464	}
		465
		466	for (; i < c; i++) {
		467	pte_t *pte;
		468
		469	page_table_lock(as, false);
2087	jermar	470	pte = page_mapping_find(as, b +
		471	i * PAGE_SIZE);
		472	ASSERT(pte && PTE_VALID(pte) &&
		473	PTE_PRESENT(pte));
		474	if (area->backend &&
		475	area->backend->frame_free) {
1424	jermar	476	area->backend->frame_free(area,
2087	jermar	477	b + i * PAGE_SIZE,
		478	PTE_GET_FRAME(pte));
1409	jermar	479	}
2087	jermar	480	page_mapping_remove(as, b +
		481	i * PAGE_SIZE);
1403	jermar	482	page_table_unlock(as, false);
		483	}
1235	jermar	484	}
		485	}
1436	jermar	486
1235	jermar	487	/*
1436	jermar	488	* Finish TLB shootdown sequence.
1235	jermar	489	*/
2183	jermar	490
2087	jermar	491	tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
		492	area->pages - pages);
1889	jermar	493	/*
		494	* Invalidate software translation caches (e.g. TSB on sparc64).
		495	*/
2087	jermar	496	as_invalidate_translation_cache(as, area->base +
		497	pages * PAGE_SIZE, area->pages - pages);
2183	jermar	498	tlb_shootdown_finalize();
		499
1235	jermar	500	} else {
		501	/*
		502	* Growing the area.
		503	* Check for overlaps with other address space areas.
		504	*/
2087	jermar	505	if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
		506	area)) {
1380	jermar	507	mutex_unlock(&area->lock);
		508	mutex_unlock(&as->lock);
1235	jermar	509	interrupts_restore(ipl);
1306	jermar	510	return EADDRNOTAVAIL;
1235	jermar	511	}
		512	}
		513
		514	area->pages = pages;
		515
1380	jermar	516	mutex_unlock(&area->lock);
		517	mutex_unlock(&as->lock);
1235	jermar	518	interrupts_restore(ipl);
		519
1306	jermar	520	return 0;
1235	jermar	521	}
		522
1306	jermar	523	/** Destroy address space area.
		524	*
		525	* @param as Address space.
		526	* @param address Address withing the area to be deleted.
		527	*
		528	* @return Zero on success or a value from @ref errno.h on failure.
		529	*/
1780	jermar	530	int as_area_destroy(as_t *as, uintptr_t address)
1306	jermar	531	{
		532	as_area_t *area;
1780	jermar	533	uintptr_t base;
1495	jermar	534	link_t *cur;
1306	jermar	535	ipl_t ipl;
		536
		537	ipl = interrupts_disable();
1380	jermar	538	mutex_lock(&as->lock);
1306	jermar	539
		540	area = find_area_and_lock(as, address);
		541	if (!area) {
1380	jermar	542	mutex_unlock(&as->lock);
1306	jermar	543	interrupts_restore(ipl);
		544	return ENOENT;
		545	}
		546
1403	jermar	547	base = area->base;
		548
1411	jermar	549	/*
1436	jermar	550	* Start TLB shootdown sequence.
		551	*/
1889	jermar	552	tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436	jermar	553
		554	/*
1411	jermar	555	* Visit only the pages mapped by used_space B+tree.
		556	*/
2087	jermar	557	for (cur = area->used_space.leaf_head.next;
		558	cur != &area->used_space.leaf_head; cur = cur->next) {
1411	jermar	559	btree_node_t *node;
2745	decky	560	unsigned int i;
1403	jermar	561
1495	jermar	562	node = list_get_instance(cur, btree_node_t, leaf_link);
		563	for (i = 0; i < node->keys; i++) {
1780	jermar	564	uintptr_t b = node->key[i];
1495	jermar	565	count_t j;
1411	jermar	566	pte_t *pte;
1403	jermar	567
1495	jermar	568	for (j = 0; j < (count_t) node->value[i]; j++) {
1411	jermar	569	page_table_lock(as, false);
2087	jermar	570	pte = page_mapping_find(as, b + j * PAGE_SIZE);
		571	ASSERT(pte && PTE_VALID(pte) &&
		572	PTE_PRESENT(pte));
		573	if (area->backend &&
		574	area->backend->frame_free) {
		575	area->backend->frame_free(area, b +
2133	jermar	576	j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403	jermar	577	}
2087	jermar	578	page_mapping_remove(as, b + j * PAGE_SIZE);
1411	jermar	579	page_table_unlock(as, false);
1306	jermar	580	}
		581	}
		582	}
1403	jermar	583
1306	jermar	584	/*
1436	jermar	585	* Finish TLB shootdown sequence.
1306	jermar	586	*/
2183	jermar	587
1889	jermar	588	tlb_invalidate_pages(as->asid, area->base, area->pages);
		589	/*
2087	jermar	590	* Invalidate potential software translation caches (e.g. TSB on
		591	* sparc64).
1889	jermar	592	*/
		593	as_invalidate_translation_cache(as, area->base, area->pages);
2183	jermar	594	tlb_shootdown_finalize();
1889	jermar	595
1436	jermar	596	btree_destroy(&area->used_space);
1306	jermar	597
1309	jermar	598	area->attributes \|= AS_AREA_ATTR_PARTIAL;
1409	jermar	599
		600	if (area->sh_info)
		601	sh_info_remove_reference(area->sh_info);
		602
1380	jermar	603	mutex_unlock(&area->lock);
1306	jermar	604
		605	/*
		606	* Remove the empty area from address space.
		607	*/
1889	jermar	608	btree_remove(&as->as_area_btree, base, NULL);
1306	jermar	609
1309	jermar	610	free(area);
		611
1889	jermar	612	mutex_unlock(&as->lock);
1306	jermar	613	interrupts_restore(ipl);
		614	return 0;
		615	}
		616
1413	jermar	617	/** Share address space area with another or the same address space.
1235	jermar	618	*
1424	jermar	619	* Address space area mapping is shared with a new address space area.
		620	* If the source address space area has not been shared so far,
		621	* a new sh_info is created. The new address space area simply gets the
		622	* sh_info of the source area. The process of duplicating the
		623	* mapping is done through the backend share function.
1413	jermar	624	*
1417	jermar	625	* @param src_as Pointer to source address space.
1239	jermar	626	* @param src_base Base address of the source address space area.
1417	jermar	627	* @param acc_size Expected size of the source area.
1428	palkovsky	628	* @param dst_as Pointer to destination address space.
1417	jermar	629	* @param dst_base Target base address.
		630	* @param dst_flags_mask Destination address space area flags mask.
1235	jermar	631	*
2007	jermar	632	* @return Zero on success or ENOENT if there is no such task or if there is no
		633	* such address space area, EPERM if there was a problem in accepting the area
		634	* or ENOMEM if there was a problem in allocating destination address space
		635	* area. ENOTSUP is returned if the address space area backend does not support
2141	jermar	636	* sharing.
1235	jermar	637	*/
1780	jermar	638	int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647	jermar	639	as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235	jermar	640	{
		641	ipl_t ipl;
1239	jermar	642	int src_flags;
		643	size_t src_size;
		644	as_area_t src_area, dst_area;
1413	jermar	645	share_info_t *sh_info;
1424	jermar	646	mem_backend_t *src_backend;
		647	mem_backend_data_t src_backend_data;
1434	palkovsky	648
1235	jermar	649	ipl = interrupts_disable();
1380	jermar	650	mutex_lock(&src_as->lock);
1329	palkovsky	651	src_area = find_area_and_lock(src_as, src_base);
1239	jermar	652	if (!src_area) {
1238	jermar	653	/*
		654	* Could not find the source address space area.
		655	*/
1380	jermar	656	mutex_unlock(&src_as->lock);
1238	jermar	657	interrupts_restore(ipl);
		658	return ENOENT;
		659	}
2007	jermar	660
1424	jermar	661	if (!src_area->backend \|\| !src_area->backend->share) {
1413	jermar	662	/*
1851	jermar	663	* There is no backend or the backend does not
1424	jermar	664	* know how to share the area.
1413	jermar	665	*/
		666	mutex_unlock(&src_area->lock);
		667	mutex_unlock(&src_as->lock);
		668	interrupts_restore(ipl);
		669	return ENOTSUP;
		670	}
		671
1239	jermar	672	src_size = src_area->pages * PAGE_SIZE;
		673	src_flags = src_area->flags;
1424	jermar	674	src_backend = src_area->backend;
		675	src_backend_data = src_area->backend_data;
1544	palkovsky	676
		677	/* Share the cacheable flag from the original mapping */
		678	if (src_flags & AS_AREA_CACHEABLE)
		679	dst_flags_mask \|= AS_AREA_CACHEABLE;
		680
2087	jermar	681	if (src_size != acc_size \|\|
		682	(src_flags & dst_flags_mask) != dst_flags_mask) {
1413	jermar	683	mutex_unlock(&src_area->lock);
		684	mutex_unlock(&src_as->lock);
1235	jermar	685	interrupts_restore(ipl);
		686	return EPERM;
		687	}
1413	jermar	688
1235	jermar	689	/*
1413	jermar	690	* Now we are committed to sharing the area.
1954	jermar	691	* First, prepare the area for sharing.
1413	jermar	692	* Then it will be safe to unlock it.
		693	*/
		694	sh_info = src_area->sh_info;
		695	if (!sh_info) {
		696	sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
		697	mutex_initialize(&sh_info->lock);
		698	sh_info->refcount = 2;
		699	btree_create(&sh_info->pagemap);
		700	src_area->sh_info = sh_info;
2647	jermar	701	/*
		702	* Call the backend to setup sharing.
		703	*/
		704	src_area->backend->share(src_area);
1413	jermar	705	} else {
		706	mutex_lock(&sh_info->lock);
		707	sh_info->refcount++;
		708	mutex_unlock(&sh_info->lock);
		709	}
		710
		711	mutex_unlock(&src_area->lock);
		712	mutex_unlock(&src_as->lock);
		713
		714	/*
1239	jermar	715	* Create copy of the source address space area.
		716	* The destination area is created with AS_AREA_ATTR_PARTIAL
		717	* attribute set which prevents race condition with
		718	* preliminary as_page_fault() calls.
1417	jermar	719	* The flags of the source area are masked against dst_flags_mask
		720	* to support sharing in less privileged mode.
1235	jermar	721	*/
1461	palkovsky	722	dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087	jermar	723	AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239	jermar	724	if (!dst_area) {
1235	jermar	725	/*
		726	* Destination address space area could not be created.
		727	*/
1413	jermar	728	sh_info_remove_reference(sh_info);
		729
1235	jermar	730	interrupts_restore(ipl);
		731	return ENOMEM;
		732	}
2009	jermar	733
1235	jermar	734	/*
1239	jermar	735	* Now the destination address space area has been
		736	* fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413	jermar	737	* attribute and set the sh_info.
1239	jermar	738	*/
2009	jermar	739	mutex_lock(&dst_as->lock);
1380	jermar	740	mutex_lock(&dst_area->lock);
1239	jermar	741	dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413	jermar	742	dst_area->sh_info = sh_info;
1380	jermar	743	mutex_unlock(&dst_area->lock);
2009	jermar	744	mutex_unlock(&dst_as->lock);
		745
1235	jermar	746	interrupts_restore(ipl);
		747
		748	return 0;
		749	}
		750
1423	jermar	751	/** Check access mode for address space area.
		752	*
		753	* The address space area must be locked prior to this call.
		754	*
		755	* @param area Address space area.
		756	* @param access Access mode.
		757	*
		758	* @return False if access violates area's permissions, true otherwise.
		759	*/
		760	bool as_area_check_access(as_area_t *area, pf_access_t access)
		761	{
		762	int flagmap[] = {
		763	[PF_ACCESS_READ] = AS_AREA_READ,
		764	[PF_ACCESS_WRITE] = AS_AREA_WRITE,
		765	[PF_ACCESS_EXEC] = AS_AREA_EXEC
		766	};
		767
		768	if (!(area->flags & flagmap[access]))
		769	return false;
		770
		771	return true;
		772	}
		773
703	jermar	774	/** Handle page fault within the current address space.
		775	*
1409	jermar	776	* This is the high-level page fault handler. It decides
		777	* whether the page fault can be resolved by any backend
		778	* and if so, it invokes the backend to resolve the page
		779	* fault.
		780	*
703	jermar	781	* Interrupts are assumed disabled.
		782	*
		783	* @param page Faulting page.
1411	jermar	784	* @param access Access mode that caused the fault (i.e. read/write/exec).
1288	jermar	785	* @param istate Pointer to interrupted state.
703	jermar	786	*
1409	jermar	787	* @return AS_PF_FAULT on page fault, AS_PF_OK on success or AS_PF_DEFER if the
		788	* fault was caused by copy_to_uspace() or copy_from_uspace().
703	jermar	789	*/
1780	jermar	790	int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703	jermar	791	{
1044	jermar	792	pte_t *pte;
977	jermar	793	as_area_t *area;
703	jermar	794
1380	jermar	795	if (!THREAD)
1409	jermar	796	return AS_PF_FAULT;
1380	jermar	797
703	jermar	798	ASSERT(AS);
1044	jermar	799
1380	jermar	800	mutex_lock(&AS->lock);
977	jermar	801	area = find_area_and_lock(AS, page);
703	jermar	802	if (!area) {
		803	/*
		804	* No area contained mapping for 'page'.
		805	* Signal page fault to low-level handler.
		806	*/
1380	jermar	807	mutex_unlock(&AS->lock);
1288	jermar	808	goto page_fault;
703	jermar	809	}
		810
1239	jermar	811	if (area->attributes & AS_AREA_ATTR_PARTIAL) {
		812	/*
		813	* The address space area is not fully initialized.
		814	* Avoid possible race by returning error.
		815	*/
1380	jermar	816	mutex_unlock(&area->lock);
		817	mutex_unlock(&AS->lock);
1288	jermar	818	goto page_fault;
1239	jermar	819	}
		820
1424	jermar	821	if (!area->backend \|\| !area->backend->page_fault) {
1409	jermar	822	/*
		823	* The address space area is not backed by any backend
		824	* or the backend cannot handle page faults.
		825	*/
		826	mutex_unlock(&area->lock);
		827	mutex_unlock(&AS->lock);
		828	goto page_fault;
		829	}
1179	jermar	830
1044	jermar	831	page_table_lock(AS, false);
		832
703	jermar	833	/*
1044	jermar	834	* To avoid race condition between two page faults
		835	* on the same address, we need to make sure
		836	* the mapping has not been already inserted.
		837	*/
		838	if ((pte = page_mapping_find(AS, page))) {
		839	if (PTE_PRESENT(pte)) {
1423	jermar	840	if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) \|\|
2087	jermar	841	(access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) \|\|
		842	(access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423	jermar	843	page_table_unlock(AS, false);
		844	mutex_unlock(&area->lock);
		845	mutex_unlock(&AS->lock);
		846	return AS_PF_OK;
		847	}
1044	jermar	848	}
		849	}
1409	jermar	850
1044	jermar	851	/*
1409	jermar	852	* Resort to the backend page fault handler.
703	jermar	853	*/
1424	jermar	854	if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409	jermar	855	page_table_unlock(AS, false);
		856	mutex_unlock(&area->lock);
		857	mutex_unlock(&AS->lock);
		858	goto page_fault;
		859	}
703	jermar	860
1044	jermar	861	page_table_unlock(AS, false);
1380	jermar	862	mutex_unlock(&area->lock);
		863	mutex_unlock(&AS->lock);
1288	jermar	864	return AS_PF_OK;
		865
		866	page_fault:
		867	if (THREAD->in_copy_from_uspace) {
		868	THREAD->in_copy_from_uspace = false;
2087	jermar	869	istate_set_retaddr(istate,
		870	(uintptr_t) &memcpy_from_uspace_failover_address);
1288	jermar	871	} else if (THREAD->in_copy_to_uspace) {
		872	THREAD->in_copy_to_uspace = false;
2087	jermar	873	istate_set_retaddr(istate,
		874	(uintptr_t) &memcpy_to_uspace_failover_address);
1288	jermar	875	} else {
		876	return AS_PF_FAULT;
		877	}
		878
		879	return AS_PF_DEFER;
703	jermar	880	}
		881
823	jermar	882	/** Switch address spaces.
703	jermar	883	*
1380	jermar	884	* Note that this function cannot sleep as it is essentially a part of
2170	jermar	885	* scheduling. Sleeping here would lead to deadlock on wakeup. Another
		886	* thing which is forbidden in this context is locking the address space.
1380	jermar	887	*
2183	jermar	888	* When this function is enetered, no spinlocks may be held.
		889	*
823	jermar	890	* @param old Old address space or NULL.
		891	* @param new New address space.
703	jermar	892	*/
2106	jermar	893	void as_switch(as_t old_as, as_t new_as)
703	jermar	894	{
2183	jermar	895	DEADLOCK_PROBE_INIT(p_asidlock);
		896	preemption_disable();
		897	retry:
		898	(void) interrupts_disable();
		899	if (!spinlock_trylock(&asidlock)) {
		900	/*
		901	* Avoid deadlock with TLB shootdown.
		902	* We can enable interrupts here because
		903	* preemption is disabled. We should not be
		904	* holding any other lock.
		905	*/
		906	(void) interrupts_enable();
		907	DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
		908	goto retry;
		909	}
		910	preemption_enable();
703	jermar	911
		912	/*
823	jermar	913	* First, take care of the old address space.
		914	*/
2106	jermar	915	if (old_as) {
		916	ASSERT(old_as->cpu_refcount);
		917	if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823	jermar	918	/*
		919	* The old address space is no longer active on
		920	* any processor. It can be appended to the
		921	* list of inactive address spaces with assigned
		922	* ASID.
		923	*/
2141	jermar	924	ASSERT(old_as->asid != ASID_INVALID);
		925	list_append(&old_as->inactive_as_with_asid_link,
		926	&inactive_as_with_asid_head);
823	jermar	927	}
1890	jermar	928
		929	/*
		930	* Perform architecture-specific tasks when the address space
		931	* is being removed from the CPU.
		932	*/
2106	jermar	933	as_deinstall_arch(old_as);
823	jermar	934	}
		935
		936	/*
		937	* Second, prepare the new address space.
		938	*/
2106	jermar	939	if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170	jermar	940	if (new_as->asid != ASID_INVALID)
2106	jermar	941	list_remove(&new_as->inactive_as_with_asid_link);
2170	jermar	942	else
		943	new_as->asid = asid_get();
823	jermar	944	}
2106	jermar	945	#ifdef AS_PAGE_TABLE
		946	SET_PTL0_ADDRESS(new_as->genarch.page_table);
		947	#endif
823	jermar	948
		949	/*
703	jermar	950	* Perform architecture-specific steps.
727	jermar	951	* (e.g. write ASID to hardware register etc.)
703	jermar	952	*/
2106	jermar	953	as_install_arch(new_as);
2170	jermar	954
		955	spinlock_unlock(&asidlock);
703	jermar	956
2106	jermar	957	AS = new_as;
703	jermar	958	}
754	jermar	959
3013	svoboda	960	/** Write directly into a page, bypassing area flags.
		961	*
		962	* This allows a debugger to write into a page that is mapped read-only
		963	* (such as the text segment). Naturally, this is only possible if the
		964	* correspoinding area is not shared and anonymous.
		965	*
		966	* FIXME: doesn't take into account that it isn't a good idea to write
		967	* into the frame if the area is shared or isn't anonymous
		968	*/
		969	static int debug_write_inside_page(uintptr_t va, void *data, size_t n)
		970	{
		971	uintptr_t page;
		972	pte_t *pte;
		973	as_area_t *area;
		974	uintptr_t frame;
		975	ipl_t ipl;
		976	int rc;
		977
		978	page = ALIGN_DOWN(va, PAGE_SIZE);
		979	ASSERT(ALIGN_DOWN(va + n - 1, PAGE_SIZE) == page);
		980
		981	restart:
		982	mutex_lock(&AS->lock);
		983	ipl = interrupts_disable();
		984	area = find_area_and_lock(AS, page);
3036	svoboda	985	if (area->backend != &anon_backend \|\| area->sh_info != NULL) {
		986	mutex_unlock(&area->lock);
		987	mutex_unlock(&AS->lock);
		988	interrupts_restore(ipl);
3013	svoboda	989
3036	svoboda	990	rc = as_area_make_writeable(area->base);
		991	if (rc != 0) return rc;
		992
		993	goto restart;
		994	}
		995
3013	svoboda	996	pte = page_mapping_find(AS, page);
		997	if (! (pte && PTE_VALID(pte) && PTE_PRESENT(pte)) ) {
		998	mutex_unlock(&area->lock);
		999	mutex_unlock(&AS->lock);
		1000	interrupts_restore(ipl);
		1001
		1002	rc = as_page_fault(page, PF_ACCESS_WRITE, NULL);
		1003	if (rc == AS_PF_FAULT) return EINVAL;
		1004
		1005	goto restart;
		1006	}
		1007
		1008	frame = PTE_GET_FRAME(pte);
		1009	memcpy((void *)(PA2KA(frame) + (va - page)), data, n);
		1010
		1011	mutex_unlock(&area->lock);
		1012	mutex_unlock(&AS->lock);
		1013	interrupts_restore(ipl);
		1014
		1015	return EOK;
		1016	}
		1017
		1018	/** Write data bypassing area flags.
		1019	*
		1020	* See debug_write_inside_page().
		1021	*/
		1022	int as_debug_write(uintptr_t va, void *data, size_t n)
		1023	{
		1024	size_t now;
		1025	int rc;
		1026
		1027	while (n > 0) {
3127	svoboda	1028	/* Number of bytes until the end of page */
		1029	now = ALIGN_DOWN(va, PAGE_SIZE) + PAGE_SIZE - va;
3013	svoboda	1030	if (now > n) now = n;
		1031
		1032	rc = debug_write_inside_page(va, data, now);
		1033	if (rc != EOK) return rc;
		1034
		1035	va += now;
		1036	data += now;
		1037	n -= now;
		1038	}
		1039
		1040	return EOK;
		1041	}
		1042
3036	svoboda	1043	/** Make sure area is private and anonymous.
		1044	*
		1045	* Not atomic atm.
		1046	* @param address Virtual address in AS.
		1047	*/
		1048	int as_area_make_writeable(uintptr_t address)
		1049	{
		1050	ipl_t ipl;
		1051	as_area_t *area;
		1052	uintptr_t base, page;
		1053	uintptr_t old_frame, frame;
		1054	size_t size;
		1055	int flags;
		1056	int page_flags;
		1057	pte_t *pte;
		1058	int rc;
		1059	uintptr_t *pagemap;
		1060
		1061	ipl = interrupts_disable();
		1062	mutex_lock(&AS->lock);
		1063	area = find_area_and_lock(AS, address);
		1064	if (!area) {
		1065	/*
		1066	* Could not find the address space area.
		1067	*/
		1068	mutex_unlock(&AS->lock);
		1069	interrupts_restore(ipl);
		1070	return ENOENT;
		1071	}
		1072
		1073	if (area->backend == &anon_backend && !area->sh_info) {
		1074	/* Nothing to do */
		1075	mutex_unlock(&area->lock);
		1076	mutex_unlock(&AS->lock);
		1077	interrupts_restore(ipl);
		1078	return EOK;
		1079	}
		1080
		1081	base = area->base;
		1082	size = area->pages * PAGE_SIZE;
		1083	flags = area->flags;
		1084	page_flags = as_area_get_flags(area);
		1085
		1086	pagemap = malloc(area->pages * sizeof(uintptr_t), 0);
		1087	page_table_lock(AS, false);
		1088
		1089	for (page = base; page < base + size; page += PAGE_SIZE) {
		1090	pte = page_mapping_find(AS, page);
		1091	if (!pte \|\| !PTE_PRESENT(pte) \|\| !PTE_READABLE(pte)) {
		1092	/* Fetch the missing page */
		1093	if (!area->backend \|\| !area->backend->page_fault) {
		1094	page_table_unlock(AS, false);
		1095	mutex_unlock(&area->lock);
		1096	mutex_unlock(&AS->lock);
		1097	interrupts_restore(ipl);
		1098	return EINVAL;
		1099	}
		1100	if (area->backend->page_fault(area, page, PF_ACCESS_READ) != AS_PF_OK) {
		1101	page_table_unlock(AS, false);
		1102	mutex_unlock(&area->lock);
		1103	mutex_unlock(&AS->lock);
		1104	interrupts_restore(ipl);
		1105	return EINVAL;
		1106	}
		1107	}
		1108	ASSERT(PTE_VALID(pte));
		1109
		1110	old_frame = PTE_GET_FRAME(pte);
		1111
		1112	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
		1113	memcpy((void ) PA2KA(frame), (void )PA2KA(old_frame),
		1114	FRAME_SIZE);
		1115
		1116	pagemap[(page - base) / PAGE_SIZE] = frame;
		1117	}
		1118
		1119	page_table_unlock(AS, false);
		1120	mutex_unlock(&area->lock);
		1121	mutex_unlock(&AS->lock);
		1122	interrupts_restore(ipl);
		1123
		1124	rc = as_area_destroy(AS, address);
		1125	if (rc < 0) {
		1126	free(pagemap);
		1127	return rc;
		1128	}
		1129
		1130	area = as_area_create(AS, flags, size, base, AS_AREA_ATTR_PARTIAL,
		1131	&anon_backend, NULL);
		1132	if (area == NULL) {
		1133	free(pagemap);
		1134	return rc;
		1135	}
		1136
		1137	mutex_lock(&AS->lock);
		1138	mutex_lock(&area->lock);
		1139	page_table_lock(AS, false);
		1140	for (page = base; page < base + size; page += PAGE_SIZE) {
		1141	frame = pagemap[(page - base) / PAGE_SIZE];
		1142
		1143	page_mapping_insert(AS, page, frame, page_flags);
		1144	if (!used_space_insert(area, page, 1))
		1145	panic("Could not insert used space.\n");
		1146	}
		1147
		1148	page_table_unlock(AS, false);
		1149
		1150	area->attributes &= ~AS_AREA_ATTR_PARTIAL;
		1151
		1152	mutex_unlock(&area->lock);
		1153	mutex_unlock(&AS->lock);
		1154
		1155	free(pagemap);
		1156
		1157	return EOK;
		1158	}
		1159
1235	jermar	1160	/** Convert address space area flags to page flags.
754	jermar	1161	*
1235	jermar	1162	* @param aflags Flags of some address space area.
754	jermar	1163	*
1235	jermar	1164	* @return Flags to be passed to page_mapping_insert().
754	jermar	1165	*/
1235	jermar	1166	int area_flags_to_page_flags(int aflags)
754	jermar	1167	{
		1168	int flags;
		1169
1178	jermar	1170	flags = PAGE_USER \| PAGE_PRESENT;
754	jermar	1171
1235	jermar	1172	if (aflags & AS_AREA_READ)
1026	jermar	1173	flags \|= PAGE_READ;
		1174
1235	jermar	1175	if (aflags & AS_AREA_WRITE)
1026	jermar	1176	flags \|= PAGE_WRITE;
		1177
1235	jermar	1178	if (aflags & AS_AREA_EXEC)
1026	jermar	1179	flags \|= PAGE_EXEC;
		1180
1424	jermar	1181	if (aflags & AS_AREA_CACHEABLE)
1178	jermar	1182	flags \|= PAGE_CACHEABLE;
		1183
754	jermar	1184	return flags;
		1185	}
756	jermar	1186
1235	jermar	1187	/** Compute flags for virtual address translation subsytem.
		1188	*
		1189	* The address space area must be locked.
		1190	* Interrupts must be disabled.
		1191	*
		1192	* @param a Address space area.
		1193	*
		1194	* @return Flags to be used in page_mapping_insert().
		1195	*/
1409	jermar	1196	int as_area_get_flags(as_area_t *a)
1235	jermar	1197	{
		1198	return area_flags_to_page_flags(a->flags);
		1199	}
		1200
756	jermar	1201	/** Create page table.
		1202	*
		1203	* Depending on architecture, create either address space
		1204	* private or global page table.
		1205	*
		1206	* @param flags Flags saying whether the page table is for kernel address space.
		1207	*
		1208	* @return First entry of the page table.
		1209	*/
		1210	pte_t *page_table_create(int flags)
		1211	{
2125	decky	1212	#ifdef __OBJC__
		1213	return [as_t page_table_create: flags];
		1214	#else
		1215	ASSERT(as_operations);
		1216	ASSERT(as_operations->page_table_create);
		1217
		1218	return as_operations->page_table_create(flags);
		1219	#endif
756	jermar	1220	}
977	jermar	1221
1468	jermar	1222	/** Destroy page table.
		1223	*
		1224	* Destroy page table in architecture specific way.
		1225	*
		1226	* @param page_table Physical address of PTL0.
		1227	*/
		1228	void page_table_destroy(pte_t *page_table)
		1229	{
2125	decky	1230	#ifdef __OBJC__
		1231	return [as_t page_table_destroy: page_table];
		1232	#else
		1233	ASSERT(as_operations);
		1234	ASSERT(as_operations->page_table_destroy);
		1235
		1236	as_operations->page_table_destroy(page_table);
		1237	#endif
1468	jermar	1238	}
		1239
1044	jermar	1240	/** Lock page table.
		1241	*
		1242	* This function should be called before any page_mapping_insert(),
		1243	* page_mapping_remove() and page_mapping_find().
		1244	*
		1245	* Locking order is such that address space areas must be locked
		1246	* prior to this call. Address space can be locked prior to this
		1247	* call in which case the lock argument is false.
		1248	*
		1249	* @param as Address space.
1248	jermar	1250	* @param lock If false, do not attempt to lock as->lock.
1044	jermar	1251	*/
		1252	void page_table_lock(as_t *as, bool lock)
		1253	{
2125	decky	1254	#ifdef __OBJC__
		1255	[as page_table_lock: lock];
		1256	#else
1044	jermar	1257	ASSERT(as_operations);
		1258	ASSERT(as_operations->page_table_lock);
2125	decky	1259
1044	jermar	1260	as_operations->page_table_lock(as, lock);
2125	decky	1261	#endif
1044	jermar	1262	}
		1263
		1264	/** Unlock page table.
		1265	*
		1266	* @param as Address space.
1248	jermar	1267	* @param unlock If false, do not attempt to unlock as->lock.
1044	jermar	1268	*/
		1269	void page_table_unlock(as_t *as, bool unlock)
		1270	{
2125	decky	1271	#ifdef __OBJC__
		1272	[as page_table_unlock: unlock];
		1273	#else
1044	jermar	1274	ASSERT(as_operations);
		1275	ASSERT(as_operations->page_table_unlock);
2125	decky	1276
1044	jermar	1277	as_operations->page_table_unlock(as, unlock);
2125	decky	1278	#endif
1044	jermar	1279	}
		1280
977	jermar	1281
		1282	/** Find address space area and lock it.
		1283	*
		1284	* The address space must be locked and interrupts must be disabled.
		1285	*
		1286	* @param as Address space.
		1287	* @param va Virtual address.
		1288	*
2087	jermar	1289	* @return Locked address space area containing va on success or NULL on
		1290	* failure.
977	jermar	1291	*/
1780	jermar	1292	as_area_t find_area_and_lock(as_t as, uintptr_t va)
977	jermar	1293	{
		1294	as_area_t *a;
1147	jermar	1295	btree_node_t leaf, lnode;
2745	decky	1296	unsigned int i;
977	jermar	1297
1147	jermar	1298	a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
		1299	if (a) {
		1300	/* va is the base address of an address space area */
1380	jermar	1301	mutex_lock(&a->lock);
1147	jermar	1302	return a;
		1303	}
		1304
		1305	/*
1150	jermar	1306	* Search the leaf node and the righmost record of its left neighbour
1147	jermar	1307	* to find out whether this is a miss or va belongs to an address
		1308	* space area found there.
		1309	*/
		1310
		1311	/* First, search the leaf node itself. */
		1312	for (i = 0; i < leaf->keys; i++) {
		1313	a = (as_area_t *) leaf->value[i];
1380	jermar	1314	mutex_lock(&a->lock);
1147	jermar	1315	if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
		1316	return a;
		1317	}
1380	jermar	1318	mutex_unlock(&a->lock);
1147	jermar	1319	}
977	jermar	1320
1147	jermar	1321	/*
1150	jermar	1322	* Second, locate the left neighbour and test its last record.
1148	jermar	1323	* Because of its position in the B+tree, it must have base < va.
1147	jermar	1324	*/
2087	jermar	1325	lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
		1326	if (lnode) {
1147	jermar	1327	a = (as_area_t *) lnode->value[lnode->keys - 1];
1380	jermar	1328	mutex_lock(&a->lock);
1147	jermar	1329	if (va < a->base + a->pages * PAGE_SIZE) {
1048	jermar	1330	return a;
1147	jermar	1331	}
1380	jermar	1332	mutex_unlock(&a->lock);
977	jermar	1333	}
		1334
		1335	return NULL;
		1336	}
1048	jermar	1337
		1338	/** Check area conflicts with other areas.
		1339	*
		1340	* The address space must be locked and interrupts must be disabled.
		1341	*
		1342	* @param as Address space.
		1343	* @param va Starting virtual address of the area being tested.
		1344	* @param size Size of the area being tested.
		1345	* @param avoid_area Do not touch this area.
		1346	*
		1347	* @return True if there is no conflict, false otherwise.
		1348	*/
2087	jermar	1349	bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
		1350	as_area_t *avoid_area)
1048	jermar	1351	{
		1352	as_area_t *a;
1147	jermar	1353	btree_node_t leaf, node;
2745	decky	1354	unsigned int i;
1048	jermar	1355
1070	jermar	1356	/*
		1357	* We don't want any area to have conflicts with NULL page.
		1358	*/
		1359	if (overlaps(va, size, NULL, PAGE_SIZE))
		1360	return false;
		1361
1147	jermar	1362	/*
		1363	* The leaf node is found in O(log n), where n is proportional to
		1364	* the number of address space areas belonging to as.
		1365	* The check for conflicts is then attempted on the rightmost
1150	jermar	1366	* record in the left neighbour, the leftmost record in the right
		1367	* neighbour and all records in the leaf node itself.
1147	jermar	1368	*/
1048	jermar	1369
1147	jermar	1370	if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
		1371	if (a != avoid_area)
		1372	return false;
		1373	}
		1374
		1375	/* First, check the two border cases. */
1150	jermar	1376	if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147	jermar	1377	a = (as_area_t *) node->value[node->keys - 1];
1380	jermar	1378	mutex_lock(&a->lock);
1147	jermar	1379	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1380	mutex_unlock(&a->lock);
1147	jermar	1381	return false;
		1382	}
1380	jermar	1383	mutex_unlock(&a->lock);
1147	jermar	1384	}
2087	jermar	1385	node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
		1386	if (node) {
1147	jermar	1387	a = (as_area_t *) node->value[0];
1380	jermar	1388	mutex_lock(&a->lock);
1147	jermar	1389	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1390	mutex_unlock(&a->lock);
1147	jermar	1391	return false;
		1392	}
1380	jermar	1393	mutex_unlock(&a->lock);
1147	jermar	1394	}
		1395
		1396	/* Second, check the leaf node. */
		1397	for (i = 0; i < leaf->keys; i++) {
		1398	a = (as_area_t *) leaf->value[i];
		1399
1048	jermar	1400	if (a == avoid_area)
		1401	continue;
1147	jermar	1402
1380	jermar	1403	mutex_lock(&a->lock);
1147	jermar	1404	if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380	jermar	1405	mutex_unlock(&a->lock);
1147	jermar	1406	return false;
		1407	}
1380	jermar	1408	mutex_unlock(&a->lock);
1048	jermar	1409	}
		1410
1070	jermar	1411	/*
		1412	* So far, the area does not conflict with other areas.
		1413	* Check if it doesn't conflict with kernel address space.
		1414	*/
		1415	if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
		1416	return !overlaps(va, size,
2087	jermar	1417	KERNEL_ADDRESS_SPACE_START,
		1418	KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070	jermar	1419	}
		1420
1048	jermar	1421	return true;
		1422	}
1235	jermar	1423
2556	jermar	1424	/** Return size of the address space area with given base.
		1425	*
		1426	* @param base Arbitrary address insede the address space area.
		1427	*
		1428	* @return Size of the address space area in bytes or zero if it
		1429	* does not exist.
		1430	*/
		1431	size_t as_area_get_size(uintptr_t base)
1329	palkovsky	1432	{
		1433	ipl_t ipl;
		1434	as_area_t *src_area;
		1435	size_t size;
		1436
		1437	ipl = interrupts_disable();
		1438	src_area = find_area_and_lock(AS, base);
		1439	if (src_area){
		1440	size = src_area->pages * PAGE_SIZE;
1380	jermar	1441	mutex_unlock(&src_area->lock);
1329	palkovsky	1442	} else {
		1443	size = 0;
		1444	}
		1445	interrupts_restore(ipl);
		1446	return size;
		1447	}
		1448
1387	jermar	1449	/** Mark portion of address space area as used.
		1450	*
		1451	* The address space area must be already locked.
		1452	*
		1453	* @param a Address space area.
		1454	* @param page First page to be marked.
		1455	* @param count Number of page to be marked.
		1456	*
		1457	* @return 0 on failure and 1 on success.
		1458	*/
1780	jermar	1459	int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387	jermar	1460	{
		1461	btree_node_t leaf, node;
		1462	count_t pages;
2745	decky	1463	unsigned int i;
1387	jermar	1464
		1465	ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
		1466	ASSERT(count);
		1467
		1468	pages = (count_t) btree_search(&a->used_space, page, &leaf);
		1469	if (pages) {
		1470	/*
		1471	* We hit the beginning of some used space.
		1472	*/
		1473	return 0;
		1474	}
		1475
1437	jermar	1476	if (!leaf->keys) {
		1477	btree_insert(&a->used_space, page, (void *) count, leaf);
		1478	return 1;
		1479	}
		1480
1387	jermar	1481	node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
		1482	if (node) {
2087	jermar	1483	uintptr_t left_pg = node->key[node->keys - 1];
		1484	uintptr_t right_pg = leaf->key[0];
		1485	count_t left_cnt = (count_t) node->value[node->keys - 1];
		1486	count_t right_cnt = (count_t) leaf->value[0];
1387	jermar	1487
		1488	/*
		1489	* Examine the possibility that the interval fits
		1490	* somewhere between the rightmost interval of
		1491	* the left neigbour and the first interval of the leaf.
		1492	*/
		1493
		1494	if (page >= right_pg) {
		1495	/* Do nothing. */
2087	jermar	1496	} else if (overlaps(page, count * PAGE_SIZE, left_pg,
		1497	left_cnt * PAGE_SIZE)) {
1387	jermar	1498	/* The interval intersects with the left interval. */
		1499	return 0;
2087	jermar	1500	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1501	right_cnt * PAGE_SIZE)) {
1387	jermar	1502	/* The interval intersects with the right interval. */
		1503	return 0;
2087	jermar	1504	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1505	(page + count * PAGE_SIZE == right_pg)) {
		1506	/*
		1507	* The interval can be added by merging the two already
		1508	* present intervals.
		1509	*/
1403	jermar	1510	node->value[node->keys - 1] += count + right_cnt;
1387	jermar	1511	btree_remove(&a->used_space, right_pg, leaf);
		1512	return 1;
2087	jermar	1513	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1514	/*
		1515	* The interval can be added by simply growing the left
		1516	* interval.
		1517	*/
1403	jermar	1518	node->value[node->keys - 1] += count;
1387	jermar	1519	return 1;
2087	jermar	1520	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1521	/*
2087	jermar	1522	* The interval can be addded by simply moving base of
		1523	* the right interval down and increasing its size
		1524	* accordingly.
1387	jermar	1525	*/
1403	jermar	1526	leaf->value[0] += count;
1387	jermar	1527	leaf->key[0] = page;
		1528	return 1;
		1529	} else {
		1530	/*
		1531	* The interval is between both neigbouring intervals,
		1532	* but cannot be merged with any of them.
		1533	*/
2087	jermar	1534	btree_insert(&a->used_space, page, (void *) count,
		1535	leaf);
1387	jermar	1536	return 1;
		1537	}
		1538	} else if (page < leaf->key[0]) {
1780	jermar	1539	uintptr_t right_pg = leaf->key[0];
1387	jermar	1540	count_t right_cnt = (count_t) leaf->value[0];
		1541
		1542	/*
2087	jermar	1543	* Investigate the border case in which the left neighbour does
		1544	* not exist but the interval fits from the left.
1387	jermar	1545	*/
		1546
2087	jermar	1547	if (overlaps(page, count * PAGE_SIZE, right_pg,
		1548	right_cnt * PAGE_SIZE)) {
1387	jermar	1549	/* The interval intersects with the right interval. */
		1550	return 0;
2087	jermar	1551	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1552	/*
2087	jermar	1553	* The interval can be added by moving the base of the
		1554	* right interval down and increasing its size
		1555	* accordingly.
1387	jermar	1556	*/
		1557	leaf->key[0] = page;
1403	jermar	1558	leaf->value[0] += count;
1387	jermar	1559	return 1;
		1560	} else {
		1561	/*
		1562	* The interval doesn't adjoin with the right interval.
		1563	* It must be added individually.
		1564	*/
2087	jermar	1565	btree_insert(&a->used_space, page, (void *) count,
		1566	leaf);
1387	jermar	1567	return 1;
		1568	}
		1569	}
		1570
		1571	node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
		1572	if (node) {
2087	jermar	1573	uintptr_t left_pg = leaf->key[leaf->keys - 1];
		1574	uintptr_t right_pg = node->key[0];
		1575	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1576	count_t right_cnt = (count_t) node->value[0];
1387	jermar	1577
		1578	/*
		1579	* Examine the possibility that the interval fits
		1580	* somewhere between the leftmost interval of
		1581	* the right neigbour and the last interval of the leaf.
		1582	*/
		1583
		1584	if (page < left_pg) {
		1585	/* Do nothing. */
2087	jermar	1586	} else if (overlaps(page, count * PAGE_SIZE, left_pg,
		1587	left_cnt * PAGE_SIZE)) {
1387	jermar	1588	/* The interval intersects with the left interval. */
		1589	return 0;
2087	jermar	1590	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1591	right_cnt * PAGE_SIZE)) {
1387	jermar	1592	/* The interval intersects with the right interval. */
		1593	return 0;
2087	jermar	1594	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1595	(page + count * PAGE_SIZE == right_pg)) {
		1596	/*
		1597	* The interval can be added by merging the two already
		1598	* present intervals.
		1599	* */
1403	jermar	1600	leaf->value[leaf->keys - 1] += count + right_cnt;
1387	jermar	1601	btree_remove(&a->used_space, right_pg, node);
		1602	return 1;
2087	jermar	1603	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1604	/*
		1605	* The interval can be added by simply growing the left
		1606	* interval.
		1607	* */
1403	jermar	1608	leaf->value[leaf->keys - 1] += count;
1387	jermar	1609	return 1;
2087	jermar	1610	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1611	/*
2087	jermar	1612	* The interval can be addded by simply moving base of
		1613	* the right interval down and increasing its size
		1614	* accordingly.
1387	jermar	1615	*/
1403	jermar	1616	node->value[0] += count;
1387	jermar	1617	node->key[0] = page;
		1618	return 1;
		1619	} else {
		1620	/*
		1621	* The interval is between both neigbouring intervals,
		1622	* but cannot be merged with any of them.
		1623	*/
2087	jermar	1624	btree_insert(&a->used_space, page, (void *) count,
		1625	leaf);
1387	jermar	1626	return 1;
		1627	}
		1628	} else if (page >= leaf->key[leaf->keys - 1]) {
1780	jermar	1629	uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387	jermar	1630	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1631
		1632	/*
2087	jermar	1633	* Investigate the border case in which the right neighbour
		1634	* does not exist but the interval fits from the right.
1387	jermar	1635	*/
		1636
2087	jermar	1637	if (overlaps(page, count * PAGE_SIZE, left_pg,
		1638	left_cnt * PAGE_SIZE)) {
1403	jermar	1639	/* The interval intersects with the left interval. */
1387	jermar	1640	return 0;
2087	jermar	1641	} else if (left_pg + left_cnt * PAGE_SIZE == page) {
		1642	/*
		1643	* The interval can be added by growing the left
		1644	* interval.
		1645	*/
1403	jermar	1646	leaf->value[leaf->keys - 1] += count;
1387	jermar	1647	return 1;
		1648	} else {
		1649	/*
		1650	* The interval doesn't adjoin with the left interval.
		1651	* It must be added individually.
		1652	*/
2087	jermar	1653	btree_insert(&a->used_space, page, (void *) count,
		1654	leaf);
1387	jermar	1655	return 1;
		1656	}
		1657	}
		1658
		1659	/*
2087	jermar	1660	* Note that if the algorithm made it thus far, the interval can fit
		1661	* only between two other intervals of the leaf. The two border cases
		1662	* were already resolved.
1387	jermar	1663	*/
		1664	for (i = 1; i < leaf->keys; i++) {
		1665	if (page < leaf->key[i]) {
2087	jermar	1666	uintptr_t left_pg = leaf->key[i - 1];
		1667	uintptr_t right_pg = leaf->key[i];
		1668	count_t left_cnt = (count_t) leaf->value[i - 1];
		1669	count_t right_cnt = (count_t) leaf->value[i];
1387	jermar	1670
		1671	/*
		1672	* The interval fits between left_pg and right_pg.
		1673	*/
		1674
2087	jermar	1675	if (overlaps(page, count * PAGE_SIZE, left_pg,
		1676	left_cnt * PAGE_SIZE)) {
		1677	/*
		1678	* The interval intersects with the left
		1679	* interval.
		1680	*/
1387	jermar	1681	return 0;
2087	jermar	1682	} else if (overlaps(page, count * PAGE_SIZE, right_pg,
		1683	right_cnt * PAGE_SIZE)) {
		1684	/*
		1685	* The interval intersects with the right
		1686	* interval.
		1687	*/
1387	jermar	1688	return 0;
2087	jermar	1689	} else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
		1690	(page + count * PAGE_SIZE == right_pg)) {
		1691	/*
		1692	* The interval can be added by merging the two
		1693	* already present intervals.
		1694	*/
1403	jermar	1695	leaf->value[i - 1] += count + right_cnt;
1387	jermar	1696	btree_remove(&a->used_space, right_pg, leaf);
		1697	return 1;
2087	jermar	1698	} else if (page == left_pg + left_cnt * PAGE_SIZE) {
		1699	/*
		1700	* The interval can be added by simply growing
		1701	* the left interval.
		1702	*/
1403	jermar	1703	leaf->value[i - 1] += count;
1387	jermar	1704	return 1;
2087	jermar	1705	} else if (page + count * PAGE_SIZE == right_pg) {
1387	jermar	1706	/*
2087	jermar	1707	* The interval can be addded by simply moving
		1708	* base of the right interval down and
		1709	* increasing its size accordingly.
1387	jermar	1710	*/
1403	jermar	1711	leaf->value[i] += count;
1387	jermar	1712	leaf->key[i] = page;
		1713	return 1;
		1714	} else {
		1715	/*
2087	jermar	1716	* The interval is between both neigbouring
		1717	* intervals, but cannot be merged with any of
		1718	* them.
1387	jermar	1719	*/
2087	jermar	1720	btree_insert(&a->used_space, page,
		1721	(void *) count, leaf);
1387	jermar	1722	return 1;
		1723	}
		1724	}
		1725	}
		1726
3424	svoboda	1727	panic("Inconsistency detected while adding %" PRIc " pages of used space at "
2087	jermar	1728	"%p.\n", count, page);
1387	jermar	1729	}
		1730
		1731	/** Mark portion of address space area as unused.
		1732	*
		1733	* The address space area must be already locked.
		1734	*
		1735	* @param a Address space area.
		1736	* @param page First page to be marked.
		1737	* @param count Number of page to be marked.
		1738	*
		1739	* @return 0 on failure and 1 on success.
		1740	*/
1780	jermar	1741	int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387	jermar	1742	{
		1743	btree_node_t leaf, node;
		1744	count_t pages;
2745	decky	1745	unsigned int i;
1387	jermar	1746
		1747	ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
		1748	ASSERT(count);
		1749
		1750	pages = (count_t) btree_search(&a->used_space, page, &leaf);
		1751	if (pages) {
		1752	/*
		1753	* We are lucky, page is the beginning of some interval.
		1754	*/
		1755	if (count > pages) {
		1756	return 0;
		1757	} else if (count == pages) {
		1758	btree_remove(&a->used_space, page, leaf);
1403	jermar	1759	return 1;
1387	jermar	1760	} else {
		1761	/*
		1762	* Find the respective interval.
		1763	* Decrease its size and relocate its start address.
		1764	*/
		1765	for (i = 0; i < leaf->keys; i++) {
		1766	if (leaf->key[i] == page) {
2087	jermar	1767	leaf->key[i] += count * PAGE_SIZE;
1403	jermar	1768	leaf->value[i] -= count;
1387	jermar	1769	return 1;
		1770	}
		1771	}
		1772	goto error;
		1773	}
		1774	}
		1775
		1776	node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
		1777	if (node && page < leaf->key[0]) {
1780	jermar	1778	uintptr_t left_pg = node->key[node->keys - 1];
1387	jermar	1779	count_t left_cnt = (count_t) node->value[node->keys - 1];
		1780
2087	jermar	1781	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1782	count * PAGE_SIZE)) {
		1783	if (page + count * PAGE_SIZE ==
		1784	left_pg + left_cnt * PAGE_SIZE) {
1387	jermar	1785	/*
2087	jermar	1786	* The interval is contained in the rightmost
		1787	* interval of the left neighbour and can be
		1788	* removed by updating the size of the bigger
		1789	* interval.
1387	jermar	1790	*/
1403	jermar	1791	node->value[node->keys - 1] -= count;
1387	jermar	1792	return 1;
2087	jermar	1793	} else if (page + count * PAGE_SIZE <
		1794	left_pg + left_cnt*PAGE_SIZE) {
1403	jermar	1795	count_t new_cnt;
1387	jermar	1796
		1797	/*
2087	jermar	1798	* The interval is contained in the rightmost
		1799	* interval of the left neighbour but its
		1800	* removal requires both updating the size of
		1801	* the original interval and also inserting a
		1802	* new interval.
1387	jermar	1803	*/
2087	jermar	1804	new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
		1805	(page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403	jermar	1806	node->value[node->keys - 1] -= count + new_cnt;
2087	jermar	1807	btree_insert(&a->used_space, page +
		1808	count * PAGE_SIZE, (void *) new_cnt, leaf);
1387	jermar	1809	return 1;
		1810	}
		1811	}
		1812	return 0;
		1813	} else if (page < leaf->key[0]) {
		1814	return 0;
		1815	}
		1816
		1817	if (page > leaf->key[leaf->keys - 1]) {
1780	jermar	1818	uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387	jermar	1819	count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
		1820
2087	jermar	1821	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1822	count * PAGE_SIZE)) {
		1823	if (page + count * PAGE_SIZE ==
		1824	left_pg + left_cnt * PAGE_SIZE) {
1387	jermar	1825	/*
2087	jermar	1826	* The interval is contained in the rightmost
		1827	* interval of the leaf and can be removed by
		1828	* updating the size of the bigger interval.
1387	jermar	1829	*/
1403	jermar	1830	leaf->value[leaf->keys - 1] -= count;
1387	jermar	1831	return 1;
2087	jermar	1832	} else if (page + count * PAGE_SIZE < left_pg +
		1833	left_cnt * PAGE_SIZE) {
1403	jermar	1834	count_t new_cnt;
1387	jermar	1835
		1836	/*
2087	jermar	1837	* The interval is contained in the rightmost
		1838	* interval of the leaf but its removal
		1839	* requires both updating the size of the
		1840	* original interval and also inserting a new
		1841	* interval.
1387	jermar	1842	*/
2087	jermar	1843	new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
		1844	(page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403	jermar	1845	leaf->value[leaf->keys - 1] -= count + new_cnt;
2087	jermar	1846	btree_insert(&a->used_space, page +
		1847	count * PAGE_SIZE, (void *) new_cnt, leaf);
1387	jermar	1848	return 1;
		1849	}
		1850	}
		1851	return 0;
		1852	}
		1853
		1854	/*
		1855	* The border cases have been already resolved.
		1856	* Now the interval can be only between intervals of the leaf.
		1857	*/
		1858	for (i = 1; i < leaf->keys - 1; i++) {
		1859	if (page < leaf->key[i]) {
1780	jermar	1860	uintptr_t left_pg = leaf->key[i - 1];
1387	jermar	1861	count_t left_cnt = (count_t) leaf->value[i - 1];
		1862
		1863	/*
2087	jermar	1864	* Now the interval is between intervals corresponding
		1865	* to (i - 1) and i.
1387	jermar	1866	*/
2087	jermar	1867	if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
		1868	count * PAGE_SIZE)) {
		1869	if (page + count * PAGE_SIZE ==
		1870	left_pg + left_cnt*PAGE_SIZE) {
1387	jermar	1871	/*
2087	jermar	1872	* The interval is contained in the
		1873	* interval (i - 1) of the leaf and can
		1874	* be removed by updating the size of
		1875	* the bigger interval.
1387	jermar	1876	*/
1403	jermar	1877	leaf->value[i - 1] -= count;
1387	jermar	1878	return 1;
2087	jermar	1879	} else if (page + count * PAGE_SIZE <
		1880	left_pg + left_cnt * PAGE_SIZE) {
1403	jermar	1881	count_t new_cnt;
1387	jermar	1882
		1883	/*
2087	jermar	1884	* The interval is contained in the
		1885	* interval (i - 1) of the leaf but its
		1886	* removal requires both updating the
		1887	* size of the original interval and
1387	jermar	1888	* also inserting a new interval.
		1889	*/
2087	jermar	1890	new_cnt = ((left_pg +
		1891	left_cnt * PAGE_SIZE) -
		1892	(page + count * PAGE_SIZE)) >>
		1893	PAGE_WIDTH;
1403	jermar	1894	leaf->value[i - 1] -= count + new_cnt;
2087	jermar	1895	btree_insert(&a->used_space, page +
		1896	count * PAGE_SIZE, (void *) new_cnt,
		1897	leaf);
1387	jermar	1898	return 1;
		1899	}
		1900	}
		1901	return 0;
		1902	}
		1903	}
		1904
		1905	error:
3424	svoboda	1906	panic("Inconsistency detected while removing %" PRIc " pages of used space "
2087	jermar	1907	"from %p.\n", count, page);
1387	jermar	1908	}
		1909
1409	jermar	1910	/** Remove reference to address space area share info.
		1911	*
		1912	* If the reference count drops to 0, the sh_info is deallocated.
		1913	*
		1914	* @param sh_info Pointer to address space area share info.
		1915	*/
		1916	void sh_info_remove_reference(share_info_t *sh_info)
		1917	{
		1918	bool dealloc = false;
		1919
		1920	mutex_lock(&sh_info->lock);
		1921	ASSERT(sh_info->refcount);
		1922	if (--sh_info->refcount == 0) {
		1923	dealloc = true;
1495	jermar	1924	link_t *cur;
1409	jermar	1925
		1926	/*
		1927	* Now walk carefully the pagemap B+tree and free/remove
		1928	* reference from all frames found there.
		1929	*/
2087	jermar	1930	for (cur = sh_info->pagemap.leaf_head.next;
		1931	cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409	jermar	1932	btree_node_t *node;
2745	decky	1933	unsigned int i;
1409	jermar	1934
1495	jermar	1935	node = list_get_instance(cur, btree_node_t, leaf_link);
		1936	for (i = 0; i < node->keys; i++)
1780	jermar	1937	frame_free((uintptr_t) node->value[i]);
1409	jermar	1938	}
		1939
		1940	}
		1941	mutex_unlock(&sh_info->lock);
		1942
		1943	if (dealloc) {
		1944	btree_destroy(&sh_info->pagemap);
		1945	free(sh_info);
		1946	}
		1947	}
		1948
1235	jermar	1949	/*
		1950	* Address space related syscalls.
		1951	*/
		1952
		1953	/** Wrapper for as_area_create(). */
1780	jermar	1954	unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235	jermar	1955	{
2087	jermar	1956	if (as_area_create(AS, flags \| AS_AREA_CACHEABLE, size, address,
		1957	AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780	jermar	1958	return (unative_t) address;
1235	jermar	1959	else
1780	jermar	1960	return (unative_t) -1;
1235	jermar	1961	}
		1962
1793	jermar	1963	/** Wrapper for as_area_resize(). */
1780	jermar	1964	unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235	jermar	1965	{
1780	jermar	1966	return (unative_t) as_area_resize(AS, address, size, 0);
1235	jermar	1967	}
		1968
1793	jermar	1969	/** Wrapper for as_area_destroy(). */
1780	jermar	1970	unative_t sys_as_area_destroy(uintptr_t address)
1306	jermar	1971	{
1780	jermar	1972	return (unative_t) as_area_destroy(AS, address);
1306	jermar	1973	}
1702	cejka	1974
1914	jermar	1975	/** Print out information about address space.
		1976	*
		1977	* @param as Address space.
		1978	*/
		1979	void as_print(as_t *as)
		1980	{
		1981	ipl_t ipl;
		1982
		1983	ipl = interrupts_disable();
		1984	mutex_lock(&as->lock);
		1985
		1986	/* print out info about address space areas */
		1987	link_t *cur;
2087	jermar	1988	for (cur = as->as_area_btree.leaf_head.next;
		1989	cur != &as->as_area_btree.leaf_head; cur = cur->next) {
		1990	btree_node_t *node;
1914	jermar	1991
2087	jermar	1992	node = list_get_instance(cur, btree_node_t, leaf_link);
		1993
2745	decky	1994	unsigned int i;
1914	jermar	1995	for (i = 0; i < node->keys; i++) {
1915	jermar	1996	as_area_t *area = node->value[i];
1914	jermar	1997
		1998	mutex_lock(&area->lock);
3424	svoboda	1999	printf("as_area: %p, base=%p, pages=%" PRIc " (%p - %p)\n",
2087	jermar	2000	area, area->base, area->pages, area->base,
3424	svoboda	2001	area->base + FRAMES2SIZE(area->pages));
1914	jermar	2002	mutex_unlock(&area->lock);
		2003	}
		2004	}
		2005
		2006	mutex_unlock(&as->lock);
		2007	interrupts_restore(ipl);
		2008	}
		2009
1757	jermar	2010	/** @}
1702	cejka	2011	*/

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(root)/branches/tracing/kernel/generic/src/mm/as.c @ 4692 – Rev 3424