Ext2FileSystem.h 6.0 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166
  1. #pragma once
  2. #include <AK/Bitmap.h>
  3. #include <Kernel/KBuffer.h>
  4. #include <Kernel/FileSystem/DiskBackedFileSystem.h>
  5. #include <Kernel/FileSystem/Inode.h>
  6. #include <Kernel/FileSystem/ext2_fs.h>
  7. #include <Kernel/UnixTypes.h>
  8. struct ext2_group_desc;
  9. struct ext2_inode;
  10. struct ext2_super_block;
  11. class Ext2FS;
  12. class Ext2FSInode final : public Inode {
  13. friend class Ext2FS;
  14. public:
  15. virtual ~Ext2FSInode() override;
  16. size_t size() const { return m_raw_inode.i_size; }
  17. bool is_symlink() const { return ::is_symlink(m_raw_inode.i_mode); }
  18. bool is_directory() const { return ::is_directory(m_raw_inode.i_mode); }
  19. // ^Inode (RefCounted magic)
  20. virtual void one_ref_left() override;
  21. private:
  22. // ^Inode
  23. virtual ssize_t read_bytes(off_t, ssize_t, u8* buffer, FileDescription*) const override;
  24. virtual InodeMetadata metadata() const override;
  25. virtual bool traverse_as_directory(Function<bool(const FS::DirectoryEntry&)>) const override;
  26. virtual InodeIdentifier lookup(StringView name) override;
  27. virtual void flush_metadata() override;
  28. virtual ssize_t write_bytes(off_t, ssize_t, const u8* data, FileDescription*) override;
  29. virtual KResult add_child(InodeIdentifier child_id, const StringView& name, mode_t) override;
  30. virtual KResult remove_child(const StringView& name) override;
  31. virtual int set_atime(time_t) override;
  32. virtual int set_ctime(time_t) override;
  33. virtual int set_mtime(time_t) override;
  34. virtual int increment_link_count() override;
  35. virtual int decrement_link_count() override;
  36. virtual size_t directory_entry_count() const override;
  37. virtual KResult chmod(mode_t) override;
  38. virtual KResult chown(uid_t, gid_t) override;
  39. virtual KResult truncate(off_t) override;
  40. bool write_directory(const Vector<FS::DirectoryEntry>&);
  41. void populate_lookup_cache() const;
  42. KResult resize(u64);
  43. Ext2FS& fs();
  44. const Ext2FS& fs() const;
  45. Ext2FSInode(Ext2FS&, unsigned index);
  46. mutable Vector<unsigned> m_block_list;
  47. mutable HashMap<String, unsigned> m_lookup_cache;
  48. ext2_inode m_raw_inode;
  49. };
  50. class Ext2FS final : public DiskBackedFS {
  51. friend class Ext2FSInode;
  52. public:
  53. static NonnullRefPtr<Ext2FS> create(NonnullRefPtr<DiskDevice>);
  54. virtual ~Ext2FS() override;
  55. virtual bool initialize() override;
  56. virtual unsigned total_block_count() const override;
  57. virtual unsigned free_block_count() const override;
  58. virtual unsigned total_inode_count() const override;
  59. virtual unsigned free_inode_count() const override;
  60. virtual KResult prepare_to_unmount() const override;
  61. private:
  62. typedef unsigned BlockIndex;
  63. typedef unsigned GroupIndex;
  64. typedef unsigned InodeIndex;
  65. explicit Ext2FS(NonnullRefPtr<DiskDevice>&&);
  66. const ext2_super_block& super_block() const { return m_super_block; }
  67. const ext2_group_desc& group_descriptor(GroupIndex) const;
  68. ext2_group_desc* block_group_descriptors() { return (ext2_group_desc*)m_cached_group_descriptor_table.value().data(); }
  69. const ext2_group_desc* block_group_descriptors() const { return (const ext2_group_desc*)m_cached_group_descriptor_table.value().data(); }
  70. void flush_block_group_descriptor_table();
  71. unsigned inodes_per_block() const;
  72. unsigned inodes_per_group() const;
  73. unsigned blocks_per_group() const;
  74. unsigned inode_size() const;
  75. bool write_ext2_inode(InodeIndex, const ext2_inode&);
  76. bool read_block_containing_inode(InodeIndex inode, BlockIndex& block_index, unsigned& offset, u8* buffer) const;
  77. bool flush_super_block();
  78. virtual const char* class_name() const override;
  79. virtual InodeIdentifier root_inode() const override;
  80. virtual RefPtr<Inode> create_inode(InodeIdentifier parentInode, const String& name, mode_t, off_t size, dev_t, int& error) override;
  81. virtual RefPtr<Inode> create_directory(InodeIdentifier parentInode, const String& name, mode_t, int& error) override;
  82. virtual RefPtr<Inode> get_inode(InodeIdentifier) const override;
  83. virtual void flush_writes() override;
  84. BlockIndex first_block_index() const;
  85. InodeIndex find_a_free_inode(GroupIndex preferred_group, off_t expected_size);
  86. Vector<BlockIndex> allocate_blocks(GroupIndex preferred_group_index, int count);
  87. BlockIndex allocate_block(GroupIndex preferred_group_index);
  88. GroupIndex group_index_from_inode(InodeIndex) const;
  89. GroupIndex group_index_from_block_index(BlockIndex) const;
  90. Vector<BlockIndex> block_list_for_inode(const ext2_inode&, bool include_block_list_blocks = false) const;
  91. bool write_block_list_for_inode(InodeIndex, ext2_inode&, const Vector<BlockIndex>&);
  92. bool get_inode_allocation_state(InodeIndex) const;
  93. bool set_inode_allocation_state(InodeIndex, bool);
  94. bool set_block_allocation_state(BlockIndex, bool);
  95. void uncache_inode(InodeIndex);
  96. void free_inode(Ext2FSInode&);
  97. struct BlockListShape {
  98. unsigned direct_blocks { 0 };
  99. unsigned indirect_blocks { 0 };
  100. unsigned doubly_indirect_blocks { 0 };
  101. unsigned triply_indirect_blocks { 0 };
  102. unsigned meta_blocks { 0 };
  103. };
  104. BlockListShape compute_block_list_shape(unsigned blocks);
  105. unsigned m_block_group_count { 0 };
  106. mutable ext2_super_block m_super_block;
  107. mutable Optional<KBuffer> m_cached_group_descriptor_table;
  108. mutable HashMap<InodeIndex, RefPtr<Ext2FSInode>> m_inode_cache;
  109. bool m_super_block_dirty { false };
  110. bool m_block_group_descriptors_dirty { false };
  111. struct CachedBitmap {
  112. CachedBitmap(BlockIndex bi, KBuffer&& buf)
  113. : bitmap_block_index(bi)
  114. , buffer(move(buf))
  115. {}
  116. BlockIndex bitmap_block_index { 0 };
  117. bool dirty { false };
  118. KBuffer buffer;
  119. Bitmap bitmap(u32 blocks_per_group) { return Bitmap::wrap(buffer.data(), blocks_per_group); }
  120. };
  121. CachedBitmap& get_bitmap_block(BlockIndex);
  122. Vector<OwnPtr<CachedBitmap>> m_cached_bitmaps;
  123. };
  124. inline Ext2FS& Ext2FSInode::fs()
  125. {
  126. return static_cast<Ext2FS&>(Inode::fs());
  127. }
  128. inline const Ext2FS& Ext2FSInode::fs() const
  129. {
  130. return static_cast<const Ext2FS&>(Inode::fs());
  131. }