banan-os/kernel/include/kernel/Epoll.h

110 lines
2.9 KiB
C++

#pragma once
#include <BAN/Array.h>
#include <BAN/CircularQueue.h>
#include <BAN/HashMap.h>
#include <BAN/HashSet.h>
#include <kernel/FS/Inode.h>
#include <limits.h>
#include <sys/epoll.h>
namespace Kernel
{
class Epoll final : public Inode
{
public:
static BAN::ErrorOr<BAN::RefPtr<Epoll>> create();
~Epoll();
BAN::ErrorOr<void> ctl(int op, int fd, BAN::RefPtr<Inode> inode, epoll_event event);
BAN::ErrorOr<size_t> wait(BAN::Span<epoll_event> events, uint64_t waketime_ns);
void notify(BAN::RefPtr<Inode> inode, uint32_t event);
private:
Epoll() = default;
public:
ino_t ino() const override { return 0; }
Mode mode() const override { return { Mode::IRUSR | Mode::IWUSR }; }
nlink_t nlink() const override { return 0; }
uid_t uid() const override { return 0; }
gid_t gid() const override { return 0; }
off_t size() const override { return 0; }
timespec atime() const override { return {}; }
timespec mtime() const override { return {}; }
timespec ctime() const override { return {}; }
blksize_t blksize() const override { return PAGE_SIZE; }
blkcnt_t blocks() const override { return 0; }
dev_t dev() const override { return 0; }
dev_t rdev() const override { return 0; }
bool is_epoll() const override { return true; }
const FileSystem* filesystem() const override { return nullptr; }
bool can_read_impl() const override { return false; }
bool can_write_impl() const override { return false; }
bool has_error_impl() const override { return false; }
bool has_hungup_impl() const override { return false; }
BAN::ErrorOr<void> fsync_impl() override { return {}; }
private:
struct InodeRefPtrHash
{
BAN::hash_t operator()(const BAN::RefPtr<Inode>& inode)
{
return BAN::hash<const Inode*>()(inode.ptr());
}
};
struct ListenEventList
{
BAN::Array<epoll_event, OPEN_MAX> events;
uint32_t bitmap[(OPEN_MAX + 31) / 32] {};
bool has_fd(int fd) const
{
// For some reason having (fd < 0 || ...) makes GCC 15.1.0
// think bitmap access can be out of bounds...
if (static_cast<size_t>(fd) >= events.size())
return false;
return bitmap[fd / 32] & (1u << (fd % 32));
}
bool empty() const
{
for (auto val : bitmap)
if (val != 0)
return false;
return true;
}
void add_fd(int fd, epoll_event event)
{
ASSERT(!has_fd(fd));
bitmap[fd / 32] |= (1u << (fd % 32));
events[fd] = event;
}
void remove_fd(int fd)
{
ASSERT(has_fd(fd));
bitmap[fd / 32] &= ~(1u << (fd % 32));
events[fd] = {};
}
};
private:
ThreadBlocker m_thread_blocker;
SpinLock m_ready_lock;
BAN::HashMap<BAN::RefPtr<Inode>, uint32_t, InodeRefPtrHash> m_ready_events;
BAN::HashMap<BAN::RefPtr<Inode>, uint32_t, InodeRefPtrHash> m_processing_events;
BAN::HashMap<BAN::RefPtr<Inode>, ListenEventList, InodeRefPtrHash> m_listening_events;
};
}