InodeFile.cpp 3.9 KB

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  1. /*
  2. * Copyright (c) 2018-2022, Andreas Kling <kling@serenityos.org>
  3. *
  4. * SPDX-License-Identifier: BSD-2-Clause
  5. */
  6. #include <AK/StringView.h>
  7. #include <Kernel/API/POSIX/errno.h>
  8. #include <Kernel/FileSystem/Inode.h>
  9. #include <Kernel/FileSystem/InodeFile.h>
  10. #include <Kernel/FileSystem/OpenFileDescription.h>
  11. #include <Kernel/FileSystem/VirtualFileSystem.h>
  12. #include <Kernel/Memory/PrivateInodeVMObject.h>
  13. #include <Kernel/Memory/SharedInodeVMObject.h>
  14. #include <Kernel/Process.h>
  15. #include <LibC/sys/ioctl_numbers.h>
  16. namespace Kernel {
  17. InodeFile::InodeFile(NonnullLockRefPtr<Inode>&& inode)
  18. : m_inode(move(inode))
  19. {
  20. }
  21. InodeFile::~InodeFile() = default;
  22. ErrorOr<size_t> InodeFile::read(OpenFileDescription& description, u64 offset, UserOrKernelBuffer& buffer, size_t count)
  23. {
  24. if (Checked<off_t>::addition_would_overflow(offset, count))
  25. return EOVERFLOW;
  26. auto nread = TRY(m_inode->read_bytes(offset, count, buffer, &description));
  27. if (nread > 0) {
  28. Thread::current()->did_file_read(nread);
  29. evaluate_block_conditions();
  30. }
  31. return nread;
  32. }
  33. ErrorOr<size_t> InodeFile::write(OpenFileDescription& description, u64 offset, UserOrKernelBuffer const& data, size_t count)
  34. {
  35. if (Checked<off_t>::addition_would_overflow(offset, count))
  36. return EOVERFLOW;
  37. size_t nwritten = TRY(m_inode->write_bytes(offset, count, data, &description));
  38. if (nwritten > 0) {
  39. auto mtime_result = m_inode->update_timestamps({}, {}, kgettimeofday().to_truncated_seconds());
  40. Thread::current()->did_file_write(nwritten);
  41. evaluate_block_conditions();
  42. if (mtime_result.is_error())
  43. return mtime_result.release_error();
  44. }
  45. return nwritten;
  46. }
  47. ErrorOr<void> InodeFile::ioctl(OpenFileDescription& description, unsigned request, Userspace<void*> arg)
  48. {
  49. switch (request) {
  50. case FIBMAP: {
  51. auto current_process_credentials = Process::current().credentials();
  52. if (!current_process_credentials->is_superuser())
  53. return EPERM;
  54. auto user_block_number = static_ptr_cast<int*>(arg);
  55. int block_number = 0;
  56. TRY(copy_from_user(&block_number, user_block_number));
  57. if (block_number < 0)
  58. return EINVAL;
  59. auto block_address = TRY(inode().get_block_address(block_number));
  60. return copy_to_user(user_block_number, &block_address);
  61. }
  62. case FIONREAD: {
  63. int remaining_bytes = inode().size() - description.offset();
  64. return copy_to_user(static_ptr_cast<int*>(arg), &remaining_bytes);
  65. }
  66. default:
  67. return EINVAL;
  68. }
  69. }
  70. ErrorOr<NonnullLockRefPtr<Memory::VMObject>> InodeFile::vmobject_for_mmap(Process&, Memory::VirtualRange const&, u64&, bool shared)
  71. {
  72. if (shared)
  73. return TRY(Memory::SharedInodeVMObject::try_create_with_inode(inode()));
  74. return TRY(Memory::PrivateInodeVMObject::try_create_with_inode(inode()));
  75. }
  76. ErrorOr<NonnullOwnPtr<KString>> InodeFile::pseudo_path(OpenFileDescription const&) const
  77. {
  78. // If it has an inode, then it has a path, and therefore the caller should have been able to get a custody at some point.
  79. VERIFY_NOT_REACHED();
  80. }
  81. ErrorOr<void> InodeFile::truncate(u64 size)
  82. {
  83. TRY(m_inode->truncate(size));
  84. TRY(m_inode->update_timestamps({}, {}, kgettimeofday().to_truncated_seconds()));
  85. return {};
  86. }
  87. ErrorOr<void> InodeFile::sync()
  88. {
  89. m_inode->sync();
  90. return {};
  91. }
  92. ErrorOr<void> InodeFile::chown(Credentials const& credentials, OpenFileDescription& description, UserID uid, GroupID gid)
  93. {
  94. VERIFY(description.inode() == m_inode);
  95. VERIFY(description.custody());
  96. return VirtualFileSystem::the().chown(credentials, *description.custody(), uid, gid);
  97. }
  98. ErrorOr<void> InodeFile::chmod(Credentials const& credentials, OpenFileDescription& description, mode_t mode)
  99. {
  100. VERIFY(description.inode() == m_inode);
  101. VERIFY(description.custody());
  102. return VirtualFileSystem::the().chmod(credentials, *description.custody(), mode);
  103. }
  104. }