ladybird/Kernel/Syscalls/inode_watcher.cpp
Brian Gianforcaro 9201a06027 Kernel: Annotate all syscalls with VERIFY_PROCESS_BIG_LOCK_ACQUIRED
Before we start disabling acquisition of the big process lock for
specific syscalls, make sure to document and assert that all the
lock is held during all syscalls.
2021-07-20 03:21:14 +02:00

96 lines
2.9 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021, sin-ack <sin-ack@protonmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/API/InodeWatcherFlags.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/FileDescription.h>
#include <Kernel/FileSystem/InodeWatcher.h>
#include <Kernel/Process.h>
namespace Kernel {
KResultOr<FlatPtr> Process::sys$create_inode_watcher(u32 flags)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(rpath);
int fd = m_fds.allocate();
if (fd < 0)
return fd;
auto watcher_or_error = InodeWatcher::create();
if (watcher_or_error.is_error())
return watcher_or_error.error();
auto description_or_error = FileDescription::create(*watcher_or_error.value());
if (description_or_error.is_error())
return description_or_error.error();
m_fds[fd].set(description_or_error.release_value());
m_fds[fd].description()->set_readable(true);
if (flags & static_cast<unsigned>(InodeWatcherFlags::Nonblock))
m_fds[fd].description()->set_blocking(false);
if (flags & static_cast<unsigned>(InodeWatcherFlags::CloseOnExec))
m_fds[fd].set_flags(m_fds[fd].flags() | FD_CLOEXEC);
return fd;
}
KResultOr<FlatPtr> Process::sys$inode_watcher_add_watch(Userspace<const Syscall::SC_inode_watcher_add_watch_params*> user_params)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(rpath);
Syscall::SC_inode_watcher_add_watch_params params;
if (!copy_from_user(&params, user_params))
return EFAULT;
auto description = fds().file_description(params.fd);
if (!description)
return EBADF;
if (!description->is_inode_watcher())
return EBADF;
auto inode_watcher = description->inode_watcher();
auto path = get_syscall_path_argument(params.user_path.characters, params.user_path.length);
if (path.is_error())
return path.error();
auto custody_or_error = VirtualFileSystem::the().resolve_path(path.value()->view(), current_directory());
if (custody_or_error.is_error())
return custody_or_error.error();
auto& custody = custody_or_error.value();
if (!custody->inode().fs().supports_watchers())
return ENOTSUP;
auto wd_or_error = inode_watcher->register_inode(custody->inode(), params.event_mask);
if (wd_or_error.is_error())
return wd_or_error.error();
return wd_or_error.value();
}
KResultOr<FlatPtr> Process::sys$inode_watcher_remove_watch(int fd, int wd)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
auto description = fds().file_description(fd);
if (!description)
return EBADF;
if (!description->is_inode_watcher())
return EBADF;
auto inode_watcher = description->inode_watcher();
auto result = inode_watcher->unregister_by_wd(wd);
if (result.is_error())
return result;
return 0;
}
}