From 52de1fe122408d7a62b6cff9ed3895ebb882d71f Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 27 Feb 2020 10:15:42 -0700 Subject: 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 --- fs/io_uring.c | 118 ++++++++++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 106 insertions(+), 12 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 7c855a038a1b..455d53fd840f 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -44,6 +44,7 @@ #include #include #include +#include #include #include #include @@ -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; -- cgit v1.2.3