SysFS.cpp 4.7 KB

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  1. /*
  2. * Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
  3. *
  4. * SPDX-License-Identifier: BSD-2-Clause
  5. */
  6. #include <AK/StringView.h>
  7. #include <Kernel/FileSystem/SysFS.h>
  8. #include <Kernel/FileSystem/SysFS/Registry.h>
  9. #include <Kernel/Sections.h>
  10. namespace Kernel {
  11. ErrorOr<NonnullRefPtr<FileSystem>> SysFS::try_create()
  12. {
  13. return TRY(adopt_nonnull_ref_or_enomem(new (nothrow) SysFS));
  14. }
  15. SysFS::SysFS() = default;
  16. SysFS::~SysFS() = default;
  17. ErrorOr<void> SysFS::initialize()
  18. {
  19. m_root_inode = TRY(SysFSComponentRegistry::the().root_directory().to_inode(*this));
  20. return {};
  21. }
  22. Inode& SysFS::root_inode()
  23. {
  24. return *m_root_inode;
  25. }
  26. ErrorOr<NonnullRefPtr<SysFSInode>> SysFSInode::try_create(SysFS const& fs, SysFSComponent const& component)
  27. {
  28. return adopt_nonnull_ref_or_enomem(new (nothrow) SysFSInode(fs, component));
  29. }
  30. SysFSInode::SysFSInode(SysFS const& fs, SysFSComponent const& component)
  31. : Inode(const_cast<SysFS&>(fs), component.component_index())
  32. , m_associated_component(component)
  33. {
  34. }
  35. void SysFSInode::did_seek(OpenFileDescription& description, off_t new_offset)
  36. {
  37. if (new_offset != 0)
  38. return;
  39. auto result = m_associated_component->refresh_data(description);
  40. if (result.is_error()) {
  41. // Subsequent calls to read will return EIO!
  42. dbgln("SysFS: Could not refresh contents: {}", result.error());
  43. }
  44. }
  45. ErrorOr<void> SysFSInode::attach(OpenFileDescription& description)
  46. {
  47. return m_associated_component->refresh_data(description);
  48. }
  49. ErrorOr<size_t> SysFSInode::read_bytes(off_t offset, size_t count, UserOrKernelBuffer& buffer, OpenFileDescription* fd) const
  50. {
  51. return m_associated_component->read_bytes(offset, count, buffer, fd);
  52. }
  53. ErrorOr<void> SysFSInode::traverse_as_directory(Function<ErrorOr<void>(FileSystem::DirectoryEntryView const&)>) const
  54. {
  55. VERIFY_NOT_REACHED();
  56. }
  57. ErrorOr<NonnullRefPtr<Inode>> SysFSInode::lookup(StringView)
  58. {
  59. VERIFY_NOT_REACHED();
  60. }
  61. InodeMetadata SysFSInode::metadata() const
  62. {
  63. // NOTE: No locking required as m_associated_component or its component index will never change during our lifetime.
  64. InodeMetadata metadata;
  65. metadata.inode = { fsid(), m_associated_component->component_index() };
  66. metadata.mode = S_IFREG | m_associated_component->permissions();
  67. metadata.uid = 0;
  68. metadata.gid = 0;
  69. metadata.size = m_associated_component->size();
  70. metadata.mtime = TimeManagement::boot_time();
  71. return metadata;
  72. }
  73. ErrorOr<void> SysFSInode::flush_metadata()
  74. {
  75. return {};
  76. }
  77. ErrorOr<size_t> SysFSInode::write_bytes(off_t offset, size_t count, UserOrKernelBuffer const& buffer, OpenFileDescription* fd)
  78. {
  79. return m_associated_component->write_bytes(offset, count, buffer, fd);
  80. }
  81. ErrorOr<NonnullRefPtr<Inode>> SysFSInode::create_child(StringView, mode_t, dev_t, UserID, GroupID)
  82. {
  83. return EROFS;
  84. }
  85. ErrorOr<void> SysFSInode::add_child(Inode&, StringView, mode_t)
  86. {
  87. return EROFS;
  88. }
  89. ErrorOr<void> SysFSInode::remove_child(StringView)
  90. {
  91. return EROFS;
  92. }
  93. ErrorOr<void> SysFSInode::chmod(mode_t)
  94. {
  95. return EPERM;
  96. }
  97. ErrorOr<void> SysFSInode::chown(UserID, GroupID)
  98. {
  99. return EPERM;
  100. }
  101. ErrorOr<void> SysFSInode::set_mtime(time_t time)
  102. {
  103. return m_associated_component->set_mtime(time);
  104. }
  105. ErrorOr<void> SysFSInode::truncate(u64 size)
  106. {
  107. return m_associated_component->truncate(size);
  108. }
  109. ErrorOr<NonnullRefPtr<SysFSDirectoryInode>> SysFSDirectoryInode::try_create(SysFS const& sysfs, SysFSComponent const& component)
  110. {
  111. return adopt_nonnull_ref_or_enomem(new (nothrow) SysFSDirectoryInode(sysfs, component));
  112. }
  113. SysFSDirectoryInode::SysFSDirectoryInode(SysFS const& fs, SysFSComponent const& component)
  114. : SysFSInode(fs, component)
  115. {
  116. }
  117. SysFSDirectoryInode::~SysFSDirectoryInode() = default;
  118. InodeMetadata SysFSDirectoryInode::metadata() const
  119. {
  120. // NOTE: No locking required as m_associated_component or its component index will never change during our lifetime.
  121. InodeMetadata metadata;
  122. metadata.inode = { fsid(), m_associated_component->component_index() };
  123. metadata.mode = S_IFDIR | S_IRUSR | S_IRGRP | S_IROTH | S_IXOTH;
  124. metadata.uid = 0;
  125. metadata.gid = 0;
  126. metadata.size = 0;
  127. metadata.mtime = TimeManagement::boot_time();
  128. return metadata;
  129. }
  130. ErrorOr<void> SysFSDirectoryInode::traverse_as_directory(Function<ErrorOr<void>(FileSystem::DirectoryEntryView const&)> callback) const
  131. {
  132. MutexLocker locker(fs().m_lock);
  133. return m_associated_component->traverse_as_directory(fs().fsid(), move(callback));
  134. }
  135. ErrorOr<NonnullRefPtr<Inode>> SysFSDirectoryInode::lookup(StringView name)
  136. {
  137. MutexLocker locker(fs().m_lock);
  138. auto component = m_associated_component->lookup(name);
  139. if (!component)
  140. return ENOENT;
  141. return TRY(component->to_inode(fs()));
  142. }
  143. }