ladybird/Kernel/FileSystem/InodeFile.cpp
Brian Gianforcaro 234c6ae32d Kernel: Change Inode::{read/write}_bytes interface to KResultOr<ssize_t>
The error handling in all these cases was still using the old style
negative values to indicate errors. We have a nicer solution for this
now with KResultOr<T>. This change switches the interface and then all
implementers to use the new style.
2021-05-02 13:27:37 +02:00

139 lines
4.0 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/StringView.h>
#include <Kernel/FileSystem/FileDescription.h>
#include <Kernel/FileSystem/Inode.h>
#include <Kernel/FileSystem/InodeFile.h>
#include <Kernel/FileSystem/VirtualFileSystem.h>
#include <Kernel/Process.h>
#include <Kernel/VM/PrivateInodeVMObject.h>
#include <Kernel/VM/SharedInodeVMObject.h>
#include <LibC/errno_numbers.h>
#include <LibC/sys/ioctl_numbers.h>
namespace Kernel {
InodeFile::InodeFile(NonnullRefPtr<Inode>&& inode)
: m_inode(move(inode))
{
}
InodeFile::~InodeFile()
{
}
KResultOr<size_t> InodeFile::read(FileDescription& description, u64 offset, UserOrKernelBuffer& buffer, size_t count)
{
if (Checked<off_t>::addition_would_overflow(offset, count))
return EOVERFLOW;
auto result = m_inode->read_bytes(offset, count, buffer, &description);
if (result.is_error())
return result.error();
auto nread = result.value();
if (nread > 0) {
Thread::current()->did_file_read(nread);
evaluate_block_conditions();
}
return nread;
}
KResultOr<size_t> InodeFile::write(FileDescription& description, u64 offset, const UserOrKernelBuffer& data, size_t count)
{
if (Checked<off_t>::addition_would_overflow(offset, count))
return EOVERFLOW;
auto result = m_inode->write_bytes(offset, count, data, &description);
if (result.is_error())
return result.error();
auto nwritten = result.value();
if (nwritten > 0) {
auto mtime_result = m_inode->set_mtime(kgettimeofday().to_truncated_seconds());
Thread::current()->did_file_write(nwritten);
evaluate_block_conditions();
if (mtime_result.is_error())
return mtime_result;
}
return nwritten;
}
int InodeFile::ioctl(FileDescription& description, unsigned request, FlatPtr arg)
{
(void)description;
switch (request) {
case FIBMAP: {
if (!Process::current()->is_superuser())
return -EPERM;
int block_number = 0;
if (!copy_from_user(&block_number, (int*)arg))
return -EFAULT;
if (block_number < 0)
return -EINVAL;
auto block_address = inode().get_block_address(block_number);
if (block_address.is_error())
return block_address.error();
if (!copy_to_user((int*)arg, &block_address.value()))
return -EFAULT;
return 0;
}
default:
return -EINVAL;
}
}
KResultOr<Region*> InodeFile::mmap(Process& process, FileDescription& description, const Range& range, u64 offset, int prot, bool shared)
{
// FIXME: If PROT_EXEC, check that the underlying file system isn't mounted noexec.
RefPtr<InodeVMObject> vmobject;
if (shared)
vmobject = SharedInodeVMObject::create_with_inode(inode());
else
vmobject = PrivateInodeVMObject::create_with_inode(inode());
if (!vmobject)
return ENOMEM;
return process.space().allocate_region_with_vmobject(range, vmobject.release_nonnull(), offset, description.absolute_path(), prot, shared);
}
String InodeFile::absolute_path(const FileDescription& description) const
{
VERIFY_NOT_REACHED();
VERIFY(description.custody());
return description.absolute_path();
}
KResult InodeFile::truncate(u64 size)
{
if (auto result = m_inode->truncate(size); result.is_error())
return result;
if (auto result = m_inode->set_mtime(kgettimeofday().to_truncated_seconds()); result.is_error())
return result;
return KSuccess;
}
KResult InodeFile::chown(FileDescription& description, uid_t uid, gid_t gid)
{
VERIFY(description.inode() == m_inode);
VERIFY(description.custody());
return VFS::the().chown(*description.custody(), uid, gid);
}
KResult InodeFile::chmod(FileDescription& description, mode_t mode)
{
VERIFY(description.inode() == m_inode);
VERIFY(description.custody());
return VFS::the().chmod(*description.custody(), mode);
}
}