1 /* 2 * Copyright 2008-2010, Ingo Weinhold, ingo_weinhold@gmx.de. 3 * Copyright 2002-2007, Axel Dörfler, axeld@pinc-software.de. All rights reserved. 4 * Distributed under the terms of the MIT License. 5 * 6 * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved. 7 * Distributed under the terms of the NewOS License. 8 */ 9 10 11 #include "paging/32bit/X86PagingStructures32Bit.h" 12 13 #include <stdlib.h> 14 15 #include <heap.h> 16 #include <util/AutoLock.h> 17 18 19 // Accessor class to reuse the SinglyLinkedListLink of DeferredDeletable for 20 // X86PagingStructures32Bit. 21 struct PagingStructuresGetLink { 22 private: 23 typedef SinglyLinkedListLink<X86PagingStructures32Bit> Link; 24 25 public: 26 inline Link* operator()(X86PagingStructures32Bit* element) const 27 { 28 return (Link*)element->GetSinglyLinkedListLink(); 29 } 30 31 inline const Link* operator()( 32 const X86PagingStructures32Bit* element) const 33 { 34 return (const Link*)element->GetSinglyLinkedListLink(); 35 } 36 }; 37 38 39 typedef SinglyLinkedList<X86PagingStructures32Bit, PagingStructuresGetLink> 40 PagingStructuresList; 41 42 43 static PagingStructuresList sPagingStructuresList; 44 static spinlock sPagingStructuresListLock; 45 46 47 X86PagingStructures32Bit::X86PagingStructures32Bit() 48 : 49 pgdir_virt(NULL) 50 { 51 } 52 53 54 X86PagingStructures32Bit::~X86PagingStructures32Bit() 55 { 56 // free the page dir 57 free(pgdir_virt); 58 } 59 60 61 void 62 X86PagingStructures32Bit::Init(page_directory_entry* virtualPageDir, 63 phys_addr_t physicalPageDir, page_directory_entry* kernelPageDir) 64 { 65 pgdir_virt = virtualPageDir; 66 pgdir_phys = physicalPageDir; 67 68 // zero out the bottom portion of the new pgdir 69 memset(pgdir_virt + FIRST_USER_PGDIR_ENT, 0, 70 NUM_USER_PGDIR_ENTS * sizeof(page_directory_entry)); 71 72 // insert this new map into the map list 73 { 74 int state = disable_interrupts(); 75 acquire_spinlock(&sPagingStructuresListLock); 76 77 // copy the top portion of the page dir from the kernel page dir 78 if (kernelPageDir != NULL) { 79 memcpy(pgdir_virt + FIRST_KERNEL_PGDIR_ENT, 80 kernelPageDir + FIRST_KERNEL_PGDIR_ENT, 81 NUM_KERNEL_PGDIR_ENTS * sizeof(page_directory_entry)); 82 } 83 84 sPagingStructuresList.Add(this); 85 86 release_spinlock(&sPagingStructuresListLock); 87 restore_interrupts(state); 88 } 89 } 90 91 92 void 93 X86PagingStructures32Bit::Delete() 94 { 95 // remove from global list 96 InterruptsSpinLocker locker(sPagingStructuresListLock); 97 sPagingStructuresList.Remove(this); 98 locker.Unlock(); 99 100 #if 0 101 // this sanity check can be enabled when corruption due to 102 // overwriting an active page directory is suspected 103 uint32 activePageDirectory = x86_read_cr3(); 104 if (activePageDirectory == pgdir_phys) 105 panic("deleting a still active page directory\n"); 106 #endif 107 108 if (are_interrupts_enabled()) 109 delete this; 110 else 111 deferred_delete(this); 112 } 113 114 115 /*static*/ void 116 X86PagingStructures32Bit::StaticInit() 117 { 118 B_INITIALIZE_SPINLOCK(&sPagingStructuresListLock); 119 new (&sPagingStructuresList) PagingStructuresList; 120 } 121 122 123 /*static*/ void 124 X86PagingStructures32Bit::UpdateAllPageDirs(int index, 125 page_directory_entry entry) 126 { 127 InterruptsSpinLocker locker(sPagingStructuresListLock); 128 129 PagingStructuresList::ConstIterator it = sPagingStructuresList.GetIterator(); 130 while (X86PagingStructures32Bit* info = it.Next()) 131 info->pgdir_virt[index] = entry; 132 } 133