io_uring: add support for epoll_ctl(2)

This adds IORING_OP_EPOLL_CTL, which can perform the same work as the
epoll_ctl(2) system call.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2020-01-08 15:18:09 -07:00
parent 39220e8d4a
commit 3e4827b05d
2 changed files with 72 additions and 0 deletions

View File

@ -74,6 +74,7 @@
#include <linux/namei.h>
#include <linux/fsnotify.h>
#include <linux/fadvise.h>
#include <linux/eventpoll.h>
#define CREATE_TRACE_POINTS
#include <trace/events/io_uring.h>
@ -423,6 +424,14 @@ struct io_madvise {
u32 advice;
};
struct io_epoll {
struct file *file;
int epfd;
int op;
int fd;
struct epoll_event event;
};
struct io_async_connect {
struct sockaddr_storage address;
};
@ -536,6 +545,7 @@ struct io_kiocb {
struct io_files_update files_update;
struct io_fadvise fadvise;
struct io_madvise madvise;
struct io_epoll epoll;
};
struct io_async_ctx *io;
@ -728,6 +738,10 @@ static const struct io_op_def io_op_defs[] = {
.fd_non_neg = 1,
.file_table = 1,
},
[IORING_OP_EPOLL_CTL] = {
.unbound_nonreg_file = 1,
.file_table = 1,
},
};
static void io_wq_submit_work(struct io_wq_work **workptr);
@ -2611,6 +2625,52 @@ static int io_openat(struct io_kiocb *req, struct io_kiocb **nxt,
return io_openat2(req, nxt, force_nonblock);
}
static int io_epoll_ctl_prep(struct io_kiocb *req,
const struct io_uring_sqe *sqe)
{
#if defined(CONFIG_EPOLL)
if (sqe->ioprio || sqe->buf_index)
return -EINVAL;
req->epoll.epfd = READ_ONCE(sqe->fd);
req->epoll.op = READ_ONCE(sqe->len);
req->epoll.fd = READ_ONCE(sqe->off);
if (ep_op_has_event(req->epoll.op)) {
struct epoll_event __user *ev;
ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
return -EFAULT;
}
return 0;
#else
return -EOPNOTSUPP;
#endif
}
static int io_epoll_ctl(struct io_kiocb *req, struct io_kiocb **nxt,
bool force_nonblock)
{
#if defined(CONFIG_EPOLL)
struct io_epoll *ie = &req->epoll;
int ret;
ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
if (force_nonblock && ret == -EAGAIN)
return -EAGAIN;
if (ret < 0)
req_set_fail_links(req);
io_cqring_add_event(req, ret);
io_put_req_find_next(req, nxt);
return 0;
#else
return -EOPNOTSUPP;
#endif
}
static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
@ -4075,6 +4135,9 @@ static int io_req_defer_prep(struct io_kiocb *req,
case IORING_OP_OPENAT2:
ret = io_openat2_prep(req, sqe);
break;
case IORING_OP_EPOLL_CTL:
ret = io_epoll_ctl_prep(req, sqe);
break;
default:
printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
req->opcode);
@ -4303,6 +4366,14 @@ static int io_issue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
}
ret = io_openat2(req, nxt, force_nonblock);
break;
case IORING_OP_EPOLL_CTL:
if (sqe) {
ret = io_epoll_ctl_prep(req, sqe);
if (ret)
break;
}
ret = io_epoll_ctl(req, nxt, force_nonblock);
break;
default:
ret = -EINVAL;
break;

View File

@ -112,6 +112,7 @@ enum {
IORING_OP_SEND,
IORING_OP_RECV,
IORING_OP_OPENAT2,
IORING_OP_EPOLL_CTL,
/* this goes last, obviously */
IORING_OP_LAST,