io_uring: add IOSQE_BUFFER_SELECT support for IORING_OP_RECVMSG

Like IORING_OP_READV, this is limited to supporting just a single
segment in the iovec passed in.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2020-02-27 10:15:42 -07:00
parent 0a384abfae
commit 52de1fe122

View File

@ -44,6 +44,7 @@
#include <linux/errno.h>
#include <linux/syscalls.h>
#include <linux/compat.h>
#include <net/compat.h>
#include <linux/refcount.h>
#include <linux/uio.h>
#include <linux/bits.h>
@ -729,6 +730,7 @@ static const struct io_op_def io_op_defs[] = {
.unbound_nonreg_file = 1,
.needs_fs = 1,
.pollin = 1,
.buffer_select = 1,
},
[IORING_OP_TIMEOUT] = {
.async_ctx = 1,
@ -3569,6 +3571,92 @@ static int io_send(struct io_kiocb *req, bool force_nonblock)
#endif
}
static int __io_recvmsg_copy_hdr(struct io_kiocb *req, struct io_async_ctx *io)
{
struct io_sr_msg *sr = &req->sr_msg;
struct iovec __user *uiov;
size_t iov_len;
int ret;
ret = __copy_msghdr_from_user(&io->msg.msg, sr->msg, &io->msg.uaddr,
&uiov, &iov_len);
if (ret)
return ret;
if (req->flags & REQ_F_BUFFER_SELECT) {
if (iov_len > 1)
return -EINVAL;
if (copy_from_user(io->msg.iov, uiov, sizeof(*uiov)))
return -EFAULT;
sr->len = io->msg.iov[0].iov_len;
iov_iter_init(&io->msg.msg.msg_iter, READ, io->msg.iov, 1,
sr->len);
io->msg.iov = NULL;
} else {
ret = import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
&io->msg.iov, &io->msg.msg.msg_iter);
if (ret > 0)
ret = 0;
}
return ret;
}
#ifdef CONFIG_COMPAT
static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
struct io_async_ctx *io)
{
struct compat_msghdr __user *msg_compat;
struct io_sr_msg *sr = &req->sr_msg;
struct compat_iovec __user *uiov;
compat_uptr_t ptr;
compat_size_t len;
int ret;
msg_compat = (struct compat_msghdr __user *) sr->msg;
ret = __get_compat_msghdr(&io->msg.msg, msg_compat, &io->msg.uaddr,
&ptr, &len);
if (ret)
return ret;
uiov = compat_ptr(ptr);
if (req->flags & REQ_F_BUFFER_SELECT) {
compat_ssize_t clen;
if (len > 1)
return -EINVAL;
if (!access_ok(uiov, sizeof(*uiov)))
return -EFAULT;
if (__get_user(clen, &uiov->iov_len))
return -EFAULT;
if (clen < 0)
return -EINVAL;
sr->len = io->msg.iov[0].iov_len;
io->msg.iov = NULL;
} else {
ret = compat_import_iovec(READ, uiov, len, UIO_FASTIOV,
&io->msg.iov,
&io->msg.msg.msg_iter);
if (ret < 0)
return ret;
}
return 0;
}
#endif
static int io_recvmsg_copy_hdr(struct io_kiocb *req, struct io_async_ctx *io)
{
io->msg.iov = io->msg.fast_iov;
#ifdef CONFIG_COMPAT
if (req->ctx->compat)
return __io_compat_recvmsg_copy_hdr(req, io);
#endif
return __io_recvmsg_copy_hdr(req, io);
}
static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
int *cflags, bool needs_lock)
{
@ -3614,9 +3702,7 @@ static int io_recvmsg_prep(struct io_kiocb *req,
if (req->flags & REQ_F_NEED_CLEANUP)
return 0;
io->msg.iov = io->msg.fast_iov;
ret = recvmsg_copy_msghdr(&io->msg.msg, sr->msg, sr->msg_flags,
&io->msg.uaddr, &io->msg.iov);
ret = io_recvmsg_copy_hdr(req, io);
if (!ret)
req->flags |= REQ_F_NEED_CLEANUP;
return ret;
@ -3630,13 +3716,14 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock)
#if defined(CONFIG_NET)
struct io_async_msghdr *kmsg = NULL;
struct socket *sock;
int ret;
int ret, cflags = 0;
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
sock = sock_from_file(req->file, &ret);
if (sock) {
struct io_buffer *kbuf;
struct io_async_ctx io;
unsigned flags;
@ -3648,19 +3735,23 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock)
kmsg->iov = kmsg->fast_iov;
kmsg->msg.msg_iter.iov = kmsg->iov;
} else {
struct io_sr_msg *sr = &req->sr_msg;
kmsg = &io.msg;
kmsg->msg.msg_name = &io.msg.addr;
io.msg.iov = io.msg.fast_iov;
ret = recvmsg_copy_msghdr(&io.msg.msg, sr->msg,
sr->msg_flags, &io.msg.uaddr,
&io.msg.iov);
ret = io_recvmsg_copy_hdr(req, &io);
if (ret)
return ret;
}
kbuf = io_recv_buffer_select(req, &cflags, !force_nonblock);
if (IS_ERR(kbuf)) {
return PTR_ERR(kbuf);
} else if (kbuf) {
kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->iov,
1, req->sr_msg.len);
}
flags = req->sr_msg.msg_flags;
if (flags & MSG_DONTWAIT)
req->flags |= REQ_F_NOWAIT;
@ -3678,7 +3769,7 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock)
if (kmsg && kmsg->iov != kmsg->fast_iov)
kfree(kmsg->iov);
req->flags &= ~REQ_F_NEED_CLEANUP;
io_cqring_add_event(req, ret);
__io_cqring_add_event(req, ret, cflags);
if (ret < 0)
req_set_fail_links(req);
io_put_req(req);
@ -4789,8 +4880,11 @@ static void io_cleanup_req(struct io_kiocb *req)
if (io->rw.iov != io->rw.fast_iov)
kfree(io->rw.iov);
break;
case IORING_OP_SENDMSG:
case IORING_OP_RECVMSG:
if (req->flags & REQ_F_BUFFER_SELECTED)
kfree(req->sr_msg.kbuf);
/* fallthrough */
case IORING_OP_SENDMSG:
if (io->msg.iov != io->msg.fast_iov)
kfree(io->msg.iov);
break;