io_uring: get rid of req->io/io_async_ctx union

There's really no point in having this union, it just means that we're
always allocating enough room to cater to any command. But that's
pointless, as the ->io field is request type private anyway.

This gets rid of the io_async_ctx structure, and fills in the required
size in the io_op_defs[] instead.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index f3d90a6108f82bd420cd4adb640c715a96df05b2..268d8c5261167d42af073b3aa5a969a3aa8eddae 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -550,15 +550,6 @@ struct io_async_rw {
        struct wait_page_queue          wpq;
 };
 
-struct io_async_ctx {
-       union {
-               struct io_async_rw      rw;
-               struct io_async_msghdr  msg;
-               struct io_async_connect connect;
-               struct io_timeout_data  timeout;
-       };
-};
-
 enum {
        REQ_F_FIXED_FILE_BIT    = IOSQE_FIXED_FILE_BIT,
        REQ_F_IO_DRAIN_BIT      = IOSQE_IO_DRAIN_BIT,
@@ -662,7 +653,8 @@ struct io_kiocb {
                struct io_completion    compl;
        };
 
-       struct io_async_ctx             *io;
+       /* opcode allocated if it needs to store data for async defer */
+       void                            *async_data;
        u8                              opcode;
        /* polled IO has completed */
        u8                              iopoll_completed;
@@ -730,8 +722,6 @@ struct io_submit_state {
 };
 
 struct io_op_def {
-       /* needs req->io allocated for deferral/async */
-       unsigned                async_ctx : 1;
        /* needs current->mm setup, does mm access */
        unsigned                needs_mm : 1;
        /* needs req->file assigned */
@@ -753,27 +743,34 @@ struct io_op_def {
        unsigned                pollout : 1;
        /* op supports buffer selection */
        unsigned                buffer_select : 1;
+       /* needs rlimit(RLIMIT_FSIZE) assigned */
        unsigned                needs_fsize : 1;
+       /* must always have async data allocated */
+       unsigned                needs_async_data : 1;
+       /* size of async data needed, if any */
+       unsigned short          async_size;
 };
 
 static const struct io_op_def io_op_defs[] __read_mostly = {
        [IORING_OP_NOP] = {},
        [IORING_OP_READV] = {
-               .async_ctx              = 1,
                .needs_mm               = 1,
                .needs_file             = 1,
                .unbound_nonreg_file    = 1,
                .pollin                 = 1,
                .buffer_select          = 1,
+               .needs_async_data       = 1,
+               .async_size             = sizeof(struct io_async_rw),
        },
        [IORING_OP_WRITEV] = {
-               .async_ctx              = 1,
                .needs_mm               = 1,
                .needs_file             = 1,
                .hash_reg_file          = 1,
                .unbound_nonreg_file    = 1,
                .pollout                = 1,
                .needs_fsize            = 1,
+               .needs_async_data       = 1,
+               .async_size             = sizeof(struct io_async_rw),
        },
        [IORING_OP_FSYNC] = {
                .needs_file             = 1,
@@ -782,6 +779,7 @@ static const struct io_op_def io_op_defs[] __read_mostly = {
                .needs_file             = 1,
                .unbound_nonreg_file    = 1,
                .pollin                 = 1,
+               .async_size             = sizeof(struct io_async_rw),
        },
        [IORING_OP_WRITE_FIXED] = {
                .needs_file             = 1,
@@ -789,6 +787,7 @@ static const struct io_op_def io_op_defs[] __read_mostly = {
                .unbound_nonreg_file    = 1,
                .pollout                = 1,
                .needs_fsize            = 1,
+               .async_size             = sizeof(struct io_async_rw),
        },
        [IORING_OP_POLL_ADD] = {
                .needs_file             = 1,
@@ -799,25 +798,28 @@ static const struct io_op_def io_op_defs[] __read_mostly = {
                .needs_file             = 1,
        },
        [IORING_OP_SENDMSG] = {
-               .async_ctx              = 1,
                .needs_mm               = 1,
                .needs_file             = 1,
                .unbound_nonreg_file    = 1,
                .needs_fs               = 1,
                .pollout                = 1,
+               .needs_async_data       = 1,
+               .async_size             = sizeof(struct io_async_msghdr),
        },
        [IORING_OP_RECVMSG] = {
-               .async_ctx              = 1,
                .needs_mm               = 1,
                .needs_file             = 1,
                .unbound_nonreg_file    = 1,
                .needs_fs               = 1,
                .pollin                 = 1,
                .buffer_select          = 1,
+               .needs_async_data       = 1,
+               .async_size             = sizeof(struct io_async_msghdr),
        },
        [IORING_OP_TIMEOUT] = {
-               .async_ctx              = 1,
                .needs_mm               = 1,
+               .needs_async_data       = 1,
+               .async_size             = sizeof(struct io_timeout_data),
        },
        [IORING_OP_TIMEOUT_REMOVE] = {},
        [IORING_OP_ACCEPT] = {
@@ -829,15 +831,17 @@ static const struct io_op_def io_op_defs[] __read_mostly = {
        },
        [IORING_OP_ASYNC_CANCEL] = {},
        [IORING_OP_LINK_TIMEOUT] = {
-               .async_ctx              = 1,
                .needs_mm               = 1,
+               .needs_async_data       = 1,
+               .async_size             = sizeof(struct io_timeout_data),
        },
        [IORING_OP_CONNECT] = {
-               .async_ctx              = 1,
                .needs_mm               = 1,
                .needs_file             = 1,
                .unbound_nonreg_file    = 1,
                .pollout                = 1,
+               .needs_async_data       = 1,
+               .async_size             = sizeof(struct io_async_connect),
        },
        [IORING_OP_FALLOCATE] = {
                .needs_file             = 1,
@@ -867,6 +871,7 @@ static const struct io_op_def io_op_defs[] __read_mostly = {
                .unbound_nonreg_file    = 1,
                .pollin                 = 1,
                .buffer_select          = 1,
+               .async_size             = sizeof(struct io_async_rw),
        },
        [IORING_OP_WRITE] = {
                .needs_mm               = 1,
@@ -874,6 +879,7 @@ static const struct io_op_def io_op_defs[] __read_mostly = {
                .unbound_nonreg_file    = 1,
                .pollout                = 1,
                .needs_fsize            = 1,
+               .async_size             = sizeof(struct io_async_rw),
        },
        [IORING_OP_FADVISE] = {
                .needs_file             = 1,
@@ -1233,9 +1239,10 @@ static void io_queue_async_work(struct io_kiocb *req)
 
 static void io_kill_timeout(struct io_kiocb *req)
 {
+       struct io_timeout_data *io = req->async_data;
        int ret;
 
-       ret = hrtimer_try_to_cancel(&req->io->timeout.timer);
+       ret = hrtimer_try_to_cancel(&io->timer);
        if (ret != -1) {
                atomic_set(&req->ctx->cq_timeouts,
                        atomic_read(&req->ctx->cq_timeouts) + 1);
@@ -1623,8 +1630,8 @@ static bool io_dismantle_req(struct io_kiocb *req)
 {
        io_clean_op(req);
 
-       if (req->io)
-               kfree(req->io);
+       if (req->async_data)
+               kfree(req->async_data);
        if (req->file)
                io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE));
 
@@ -1683,10 +1690,11 @@ static void __io_free_req(struct io_kiocb *req)
 
 static bool io_link_cancel_timeout(struct io_kiocb *req)
 {
+       struct io_timeout_data *io = req->async_data;
        struct io_ring_ctx *ctx = req->ctx;
        int ret;
 
-       ret = hrtimer_try_to_cancel(&req->io->timeout.timer);
+       ret = hrtimer_try_to_cancel(&io->timer);
        if (ret != -1) {
                io_cqring_fill_event(req, -ECANCELED);
                io_commit_cqring(ctx);
@@ -2368,7 +2376,7 @@ static bool io_resubmit_prep(struct io_kiocb *req, int error)
                goto end_req;
        }
 
-       if (!req->io) {
+       if (!req->async_data) {
                ret = io_import_iovec(rw, req, &iovec, &iter, false);
                if (ret < 0)
                        goto end_req;
@@ -2649,13 +2657,14 @@ static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
                       struct io_comp_state *cs)
 {
        struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
+       struct io_async_rw *io = req->async_data;
 
        /* add previously done IO, if any */
-       if (req->io && req->io->rw.bytes_done > 0) {
+       if (io && io->bytes_done > 0) {
                if (ret < 0)
-                       ret = req->io->rw.bytes_done;
+                       ret = io->bytes_done;
                else
-                       ret += req->io->rw.bytes_done;
+                       ret += io->bytes_done;
        }
 
        if (req->flags & REQ_F_CUR_POS)
@@ -2929,10 +2938,12 @@ static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
                               struct iovec **iovec, struct iov_iter *iter,
                               bool needs_lock)
 {
-       if (!req->io)
+       struct io_async_rw *iorw = req->async_data;
+
+       if (!iorw)
                return __io_import_iovec(rw, req, iovec, iter, needs_lock);
        *iovec = NULL;
-       return iov_iter_count(&req->io->rw.iter);
+       return iov_iter_count(&iorw->iter);
 }
 
 static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
@@ -3001,7 +3012,7 @@ static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb,
 static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
                          const struct iovec *fast_iov, struct iov_iter *iter)
 {
-       struct io_async_rw *rw = &req->io->rw;
+       struct io_async_rw *rw = req->async_data;
 
        memcpy(&rw->iter, iter, sizeof(*iter));
        rw->free_iovec = iovec;
@@ -3025,28 +3036,29 @@ static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
        }
 }
 
-static inline int __io_alloc_async_ctx(struct io_kiocb *req)
+static inline int __io_alloc_async_data(struct io_kiocb *req)
 {
-       req->io = kmalloc(sizeof(*req->io), GFP_KERNEL);
-       return req->io == NULL;
+       WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
+       req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
+       return req->async_data == NULL;
 }
 
-static int io_alloc_async_ctx(struct io_kiocb *req)
+static int io_alloc_async_data(struct io_kiocb *req)
 {
-       if (!io_op_defs[req->opcode].async_ctx)
+       if (!io_op_defs[req->opcode].needs_async_data)
                return 0;
 
-       return  __io_alloc_async_ctx(req);
+       return  __io_alloc_async_data(req);
 }
 
 static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
                             const struct iovec *fast_iov,
                             struct iov_iter *iter, bool force)
 {
-       if (!force && !io_op_defs[req->opcode].async_ctx)
+       if (!force && !io_op_defs[req->opcode].needs_async_data)
                return 0;
-       if (!req->io) {
-               if (__io_alloc_async_ctx(req))
+       if (!req->async_data) {
+               if (__io_alloc_async_data(req))
                        return -ENOMEM;
 
                io_req_map_rw(req, iovec, fast_iov, iter);
@@ -3057,7 +3069,7 @@ static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
 static inline int io_rw_prep_async(struct io_kiocb *req, int rw,
                                   bool force_nonblock)
 {
-       struct io_async_rw *iorw = &req->io->rw;
+       struct io_async_rw *iorw = req->async_data;
        struct iovec *iov = iorw->fast_iov;
        ssize_t ret;
 
@@ -3085,7 +3097,7 @@ static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
                return -EBADF;
 
        /* either don't need iovec imported or already have it */
-       if (!req->io || req->flags & REQ_F_NEED_CLEANUP)
+       if (!req->async_data || req->flags & REQ_F_NEED_CLEANUP)
                return 0;
        return io_rw_prep_async(req, READ, force_nonblock);
 }
@@ -3148,7 +3160,8 @@ static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
  */
 static bool io_rw_should_retry(struct io_kiocb *req)
 {
-       struct wait_page_queue *wait = &req->io->rw.wpq;
+       struct io_async_rw *rw = req->async_data;
+       struct wait_page_queue *wait = &rw->wpq;
        struct kiocb *kiocb = &req->rw.kiocb;
 
        /* never retry for NOWAIT, we just complete with -EAGAIN */
@@ -3192,12 +3205,13 @@ static int io_read(struct io_kiocb *req, bool force_nonblock,
        struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
        struct kiocb *kiocb = &req->rw.kiocb;
        struct iov_iter __iter, *iter = &__iter;
+       struct io_async_rw *rw = req->async_data;
        ssize_t io_size, ret, ret2;
        size_t iov_count;
        bool no_async;
 
-       if (req->io)
-               iter = &req->io->rw.iter;
+       if (rw)
+               iter = &rw->iter;
 
        ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
        if (ret < 0)
@@ -3257,12 +3271,13 @@ copy_iov:
        }
        if (no_async)
                return -EAGAIN;
+       rw = req->async_data;
        /* it's copied and will be cleaned with ->io */
        iovec = NULL;
        /* now use our persistent iterator, if we aren't already */
-       iter = &req->io->rw.iter;
+       iter = &rw->iter;
 retry:
-       req->io->rw.bytes_done += ret;
+       rw->bytes_done += ret;
        /* if we can retry, do so with the callbacks armed */
        if (!io_rw_should_retry(req)) {
                kiocb->ki_flags &= ~IOCB_WAITQ;
@@ -3306,7 +3321,7 @@ static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
                return -EBADF;
 
        /* either don't need iovec imported or already have it */
-       if (!req->io || req->flags & REQ_F_NEED_CLEANUP)
+       if (!req->async_data || req->flags & REQ_F_NEED_CLEANUP)
                return 0;
        return io_rw_prep_async(req, WRITE, force_nonblock);
 }
@@ -3317,11 +3332,12 @@ static int io_write(struct io_kiocb *req, bool force_nonblock,
        struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
        struct kiocb *kiocb = &req->rw.kiocb;
        struct iov_iter __iter, *iter = &__iter;
+       struct io_async_rw *rw = req->async_data;
        size_t iov_count;
        ssize_t ret, ret2, io_size;
 
-       if (req->io)
-               iter = &req->io->rw.iter;
+       if (rw)
+               iter = &rw->iter;
 
        ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
        if (ret < 0)
@@ -4098,15 +4114,18 @@ static int io_sync_file_range(struct io_kiocb *req, bool force_nonblock)
 static int io_setup_async_msg(struct io_kiocb *req,
                              struct io_async_msghdr *kmsg)
 {
-       if (req->io)
+       struct io_async_msghdr *async_msg = req->async_data;
+
+       if (async_msg)
                return -EAGAIN;
-       if (io_alloc_async_ctx(req)) {
+       if (io_alloc_async_data(req)) {
                if (kmsg->iov != kmsg->fast_iov)
                        kfree(kmsg->iov);
                return -ENOMEM;
        }
+       async_msg = req->async_data;
        req->flags |= REQ_F_NEED_CLEANUP;
-       memcpy(&req->io->msg, kmsg, sizeof(*kmsg));
+       memcpy(async_msg, kmsg, sizeof(*kmsg));
        return -EAGAIN;
 }
 
@@ -4121,8 +4140,8 @@ static int io_sendmsg_copy_hdr(struct io_kiocb *req,
 
 static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
+       struct io_async_msghdr *async_msg = req->async_data;
        struct io_sr_msg *sr = &req->sr_msg;
-       struct io_async_ctx *io = req->io;
        int ret;
 
        if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
@@ -4137,13 +4156,13 @@ static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
                sr->msg_flags |= MSG_CMSG_COMPAT;
 #endif
 
-       if (!io || req->opcode == IORING_OP_SEND)
+       if (!async_msg || !io_op_defs[req->opcode].needs_async_data)
                return 0;
        /* iovec is already imported */
        if (req->flags & REQ_F_NEED_CLEANUP)
                return 0;
 
-       ret = io_sendmsg_copy_hdr(req, &io->msg);
+       ret = io_sendmsg_copy_hdr(req, async_msg);
        if (!ret)
                req->flags |= REQ_F_NEED_CLEANUP;
        return ret;
@@ -4161,9 +4180,9 @@ static int io_sendmsg(struct io_kiocb *req, bool force_nonblock,
        if (unlikely(!sock))
                return ret;
 
-       if (req->io) {
-               kmsg = &req->io->msg;
-               kmsg->msg.msg_name = &req->io->msg.addr;
+       if (req->async_data) {
+               kmsg = req->async_data;
+               kmsg->msg.msg_name = &kmsg->addr;
                /* if iov is set, it's allocated already */
                if (!kmsg->iov)
                        kmsg->iov = kmsg->fast_iov;
@@ -4350,8 +4369,8 @@ static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
 static int io_recvmsg_prep(struct io_kiocb *req,
                           const struct io_uring_sqe *sqe)
 {
+       struct io_async_msghdr *async_msg = req->async_data;
        struct io_sr_msg *sr = &req->sr_msg;
-       struct io_async_ctx *io = req->io;
        int ret;
 
        if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
@@ -4367,13 +4386,13 @@ static int io_recvmsg_prep(struct io_kiocb *req,
                sr->msg_flags |= MSG_CMSG_COMPAT;
 #endif
 
-       if (!io || req->opcode == IORING_OP_RECV)
+       if (!async_msg || !io_op_defs[req->opcode].needs_async_data)
                return 0;
        /* iovec is already imported */
        if (req->flags & REQ_F_NEED_CLEANUP)
                return 0;
 
-       ret = io_recvmsg_copy_hdr(req, &io->msg);
+       ret = io_recvmsg_copy_hdr(req, async_msg);
        if (!ret)
                req->flags |= REQ_F_NEED_CLEANUP;
        return ret;
@@ -4392,9 +4411,9 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock,
        if (unlikely(!sock))
                return ret;
 
-       if (req->io) {
-               kmsg = &req->io->msg;
-               kmsg->msg.msg_name = &req->io->msg.addr;
+       if (req->async_data) {
+               kmsg = req->async_data;
+               kmsg->msg.msg_name = &kmsg->addr;
                /* if iov is set, it's allocated already */
                if (!kmsg->iov)
                        kmsg->iov = kmsg->fast_iov;
@@ -4536,7 +4555,7 @@ static int io_accept(struct io_kiocb *req, bool force_nonblock,
 static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
        struct io_connect *conn = &req->connect;
-       struct io_async_ctx *io = req->io;
+       struct io_async_connect *io = req->async_data;
 
        if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
                return -EINVAL;
@@ -4550,22 +4569,22 @@ static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
                return 0;
 
        return move_addr_to_kernel(conn->addr, conn->addr_len,
-                                       &io->connect.address);
+                                       &io->address);
 }
 
 static int io_connect(struct io_kiocb *req, bool force_nonblock,
                      struct io_comp_state *cs)
 {
-       struct io_async_ctx __io, *io;
+       struct io_async_connect __io, *io;
        unsigned file_flags;
        int ret;
 
-       if (req->io) {
-               io = req->io;
+       if (req->async_data) {
+               io = req->async_data;
        } else {
                ret = move_addr_to_kernel(req->connect.addr,
                                                req->connect.addr_len,
-                                               &__io.connect.address);
+                                               &__io.address);
                if (ret)
                        goto out;
                io = &__io;
@@ -4573,16 +4592,17 @@ static int io_connect(struct io_kiocb *req, bool force_nonblock,
 
        file_flags = force_nonblock ? O_NONBLOCK : 0;
 
-       ret = __sys_connect_file(req->file, &io->connect.address,
+       ret = __sys_connect_file(req->file, &io->address,
                                        req->connect.addr_len, file_flags);
        if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
-               if (req->io)
+               if (req->async_data)
                        return -EAGAIN;
-               if (io_alloc_async_ctx(req)) {
+               if (io_alloc_async_data(req)) {
                        ret = -ENOMEM;
                        goto out;
                }
-               memcpy(&req->io->connect, &__io.connect, sizeof(__io.connect));
+               io = req->async_data;
+               memcpy(req->async_data, &__io, sizeof(__io));
                return -EAGAIN;
        }
        if (ret == -ERESTARTSYS)
@@ -4724,9 +4744,9 @@ static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
 
 static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
 {
-       /* pure poll stashes this in ->io, poll driven retry elsewhere */
+       /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
        if (req->opcode == IORING_OP_POLL_ADD)
-               return (struct io_poll_iocb *) req->io;
+               return req->async_data;
        return req->apoll->double_poll;
 }
 
@@ -5169,7 +5189,7 @@ static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
 {
        struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
 
-       __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->io);
+       __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
 }
 
 static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
@@ -5250,11 +5270,12 @@ static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
 
 static int __io_timeout_cancel(struct io_kiocb *req)
 {
+       struct io_timeout_data *io = req->async_data;
        int ret;
 
        list_del_init(&req->timeout.list);
 
-       ret = hrtimer_try_to_cancel(&req->io->timeout.timer);
+       ret = hrtimer_try_to_cancel(&io->timer);
        if (ret == -1)
                return -EALREADY;
 
@@ -5341,10 +5362,10 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
 
        req->timeout.off = off;
 
-       if (!req->io && io_alloc_async_ctx(req))
+       if (!req->async_data && io_alloc_async_data(req))
                return -ENOMEM;
 
-       data = &req->io->timeout;
+       data = req->async_data;
        data->req = req;
 
        if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
@@ -5362,7 +5383,7 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
 static int io_timeout(struct io_kiocb *req)
 {
        struct io_ring_ctx *ctx = req->ctx;
-       struct io_timeout_data *data = &req->io->timeout;
+       struct io_timeout_data *data = req->async_data;
        struct list_head *entry;
        u32 tail, off = req->timeout.off;
 
@@ -5533,7 +5554,7 @@ static int io_req_defer_prep(struct io_kiocb *req,
        if (!sqe)
                return 0;
 
-       if (io_alloc_async_ctx(req))
+       if (io_alloc_async_data(req))
                return -EAGAIN;
        ret = io_prep_work_files(req);
        if (unlikely(ret))
@@ -5672,7 +5693,7 @@ static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe)
        if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
                return 0;
 
-       if (!req->io) {
+       if (!req->async_data) {
                ret = io_req_defer_prep(req, sqe);
                if (ret)
                        return ret;
@@ -5716,8 +5737,6 @@ static void io_req_drop_files(struct io_kiocb *req)
 
 static void __io_clean_op(struct io_kiocb *req)
 {
-       struct io_async_ctx *io = req->io;
-
        if (req->flags & REQ_F_BUFFER_SELECTED) {
                switch (req->opcode) {
                case IORING_OP_READV:
@@ -5740,15 +5759,19 @@ static void __io_clean_op(struct io_kiocb *req)
                case IORING_OP_READ:
                case IORING_OP_WRITEV:
                case IORING_OP_WRITE_FIXED:
-               case IORING_OP_WRITE:
-                       if (io->rw.free_iovec)
-                               kfree(io->rw.free_iovec);
+               case IORING_OP_WRITE: {
+                       struct io_async_rw *io = req->async_data;
+                       if (io->free_iovec)
+                               kfree(io->free_iovec);
                        break;
+                       }
                case IORING_OP_RECVMSG:
-               case IORING_OP_SENDMSG:
-                       if (io->msg.iov != io->msg.fast_iov)
-                               kfree(io->msg.iov);
+               case IORING_OP_SENDMSG: {
+                       struct io_async_msghdr *io = req->async_data;
+                       if (io->iov != io->fast_iov)
+                               kfree(io->iov);
                        break;
+                       }
                case IORING_OP_SPLICE:
                case IORING_OP_TEE:
                        io_put_file(req, req->splice.file_in,
@@ -6180,7 +6203,7 @@ static void __io_queue_linked_timeout(struct io_kiocb *req)
         * we got a chance to setup the timer
         */
        if (!list_empty(&req->link_list)) {
-               struct io_timeout_data *data = &req->io->timeout;
+               struct io_timeout_data *data = req->async_data;
 
                data->timer.function = io_link_timeout_fn;
                hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
@@ -6304,7 +6327,7 @@ fail_req:
                        io_req_complete(req, ret);
                }
        } else if (req->flags & REQ_F_FORCE_ASYNC) {
-               if (!req->io) {
+               if (!req->async_data) {
                        ret = io_req_defer_prep(req, sqe);
                        if (unlikely(ret))
                                goto fail_req;
@@ -6509,7 +6532,7 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
 
        req->opcode = READ_ONCE(sqe->opcode);
        req->user_data = READ_ONCE(sqe->user_data);
-       req->io = NULL;
+       req->async_data = NULL;
        req->file = NULL;
        req->ctx = ctx;
        req->flags = 0;