SysFS.cpp 5.6 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. #include <Kernel/Time/TimeManagement.h>
  11. namespace Kernel {
  12. ErrorOr<NonnullLockRefPtr<FileSystem>> SysFS::try_create()
  13. {
  14. return TRY(adopt_nonnull_lock_ref_or_enomem(new (nothrow) SysFS));
  15. }
  16. SysFS::SysFS() = default;
  17. SysFS::~SysFS() = default;
  18. ErrorOr<void> SysFS::initialize()
  19. {
  20. m_root_inode = TRY(SysFSComponentRegistry::the().root_directory().to_inode(*this));
  21. return {};
  22. }
  23. Inode& SysFS::root_inode()
  24. {
  25. return *m_root_inode;
  26. }
  27. ErrorOr<NonnullLockRefPtr<SysFSInode>> SysFSInode::try_create(SysFS const& fs, SysFSComponent const& component)
  28. {
  29. return adopt_nonnull_lock_ref_or_enomem(new (nothrow) SysFSInode(fs, component));
  30. }
  31. SysFSInode::SysFSInode(SysFS const& fs, SysFSComponent const& component)
  32. : Inode(const_cast<SysFS&>(fs), component.component_index())
  33. , m_associated_component(component)
  34. {
  35. }
  36. void SysFSInode::did_seek(OpenFileDescription& description, off_t new_offset)
  37. {
  38. if (new_offset != 0)
  39. return;
  40. auto result = m_associated_component->refresh_data(description);
  41. if (result.is_error()) {
  42. // Subsequent calls to read will return EIO!
  43. dbgln("SysFS: Could not refresh contents: {}", result.error());
  44. }
  45. }
  46. ErrorOr<void> SysFSInode::attach(OpenFileDescription& description)
  47. {
  48. return m_associated_component->refresh_data(description);
  49. }
  50. ErrorOr<size_t> SysFSInode::read_bytes_locked(off_t offset, size_t count, UserOrKernelBuffer& buffer, OpenFileDescription* fd) const
  51. {
  52. return m_associated_component->read_bytes(offset, count, buffer, fd);
  53. }
  54. ErrorOr<void> SysFSInode::traverse_as_directory(Function<ErrorOr<void>(FileSystem::DirectoryEntryView const&)>) const
  55. {
  56. VERIFY_NOT_REACHED();
  57. }
  58. ErrorOr<NonnullLockRefPtr<Inode>> SysFSInode::lookup(StringView)
  59. {
  60. VERIFY_NOT_REACHED();
  61. }
  62. InodeMetadata SysFSInode::metadata() const
  63. {
  64. // NOTE: No locking required as m_associated_component or its component index will never change during our lifetime.
  65. InodeMetadata metadata;
  66. metadata.inode = { fsid(), m_associated_component->component_index() };
  67. metadata.mode = S_IFREG | m_associated_component->permissions();
  68. metadata.uid = 0;
  69. metadata.gid = 0;
  70. metadata.size = m_associated_component->size();
  71. metadata.mtime = TimeManagement::boot_time();
  72. return metadata;
  73. }
  74. ErrorOr<void> SysFSInode::flush_metadata()
  75. {
  76. return {};
  77. }
  78. ErrorOr<size_t> SysFSInode::write_bytes_locked(off_t offset, size_t count, UserOrKernelBuffer const& buffer, OpenFileDescription* fd)
  79. {
  80. return m_associated_component->write_bytes(offset, count, buffer, fd);
  81. }
  82. ErrorOr<NonnullLockRefPtr<Inode>> SysFSInode::create_child(StringView, mode_t, dev_t, UserID, GroupID)
  83. {
  84. return EROFS;
  85. }
  86. ErrorOr<void> SysFSInode::add_child(Inode&, StringView, mode_t)
  87. {
  88. return EROFS;
  89. }
  90. ErrorOr<void> SysFSInode::remove_child(StringView)
  91. {
  92. return EROFS;
  93. }
  94. ErrorOr<void> SysFSInode::chmod(mode_t)
  95. {
  96. return EPERM;
  97. }
  98. ErrorOr<void> SysFSInode::chown(UserID, GroupID)
  99. {
  100. return EPERM;
  101. }
  102. ErrorOr<void> SysFSInode::truncate(u64 size)
  103. {
  104. return m_associated_component->truncate(size);
  105. }
  106. ErrorOr<void> SysFSInode::update_timestamps(Optional<time_t>, Optional<time_t>, Optional<time_t>)
  107. {
  108. return {};
  109. }
  110. ErrorOr<NonnullLockRefPtr<SysFSLinkInode>> SysFSLinkInode::try_create(SysFS const& sysfs, SysFSComponent const& component)
  111. {
  112. return adopt_nonnull_lock_ref_or_enomem(new (nothrow) SysFSLinkInode(sysfs, component));
  113. }
  114. SysFSLinkInode::SysFSLinkInode(SysFS const& fs, SysFSComponent const& component)
  115. : SysFSInode(fs, component)
  116. {
  117. }
  118. SysFSLinkInode::~SysFSLinkInode() = default;
  119. InodeMetadata SysFSLinkInode::metadata() const
  120. {
  121. // NOTE: No locking required as m_associated_component or its component index will never change during our lifetime.
  122. InodeMetadata metadata;
  123. metadata.inode = { fsid(), m_associated_component->component_index() };
  124. metadata.mode = S_IFLNK | S_IRUSR | S_IRGRP | S_IROTH | S_IXOTH;
  125. metadata.uid = 0;
  126. metadata.gid = 0;
  127. metadata.size = 0;
  128. metadata.mtime = TimeManagement::boot_time();
  129. return metadata;
  130. }
  131. ErrorOr<NonnullLockRefPtr<SysFSDirectoryInode>> SysFSDirectoryInode::try_create(SysFS const& sysfs, SysFSComponent const& component)
  132. {
  133. return adopt_nonnull_lock_ref_or_enomem(new (nothrow) SysFSDirectoryInode(sysfs, component));
  134. }
  135. SysFSDirectoryInode::SysFSDirectoryInode(SysFS const& fs, SysFSComponent const& component)
  136. : SysFSInode(fs, component)
  137. {
  138. }
  139. SysFSDirectoryInode::~SysFSDirectoryInode() = default;
  140. InodeMetadata SysFSDirectoryInode::metadata() const
  141. {
  142. // NOTE: No locking required as m_associated_component or its component index will never change during our lifetime.
  143. InodeMetadata metadata;
  144. metadata.inode = { fsid(), m_associated_component->component_index() };
  145. metadata.mode = S_IFDIR | S_IRUSR | S_IRGRP | S_IROTH | S_IXOTH;
  146. metadata.uid = 0;
  147. metadata.gid = 0;
  148. metadata.size = 0;
  149. metadata.mtime = TimeManagement::boot_time();
  150. return metadata;
  151. }
  152. ErrorOr<void> SysFSDirectoryInode::traverse_as_directory(Function<ErrorOr<void>(FileSystem::DirectoryEntryView const&)> callback) const
  153. {
  154. MutexLocker locker(fs().m_lock);
  155. return m_associated_component->traverse_as_directory(fs().fsid(), move(callback));
  156. }
  157. ErrorOr<NonnullLockRefPtr<Inode>> SysFSDirectoryInode::lookup(StringView name)
  158. {
  159. MutexLocker locker(fs().m_lock);
  160. auto component = m_associated_component->lookup(name);
  161. if (!component)
  162. return ENOENT;
  163. return TRY(component->to_inode(fs()));
  164. }
  165. }