Merge tag 'io_uring-5.5-20191226' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:

 - Removal of now unused busy wqe list (Hillf)

 - Add cond_resched() to io-wq work processing (Hillf)

 - And then the series that I hinted at from last week, which removes
   the sqe from the io_kiocb and keeps all sqe handling on the prep
   side. This guarantees that an opcode can't do the wrong thing and
   read the sqe more than once. This is unchanged from last week, no
   issues have been observed with this in testing. Hence I really think
   we should fold this into 5.5.

* tag 'io_uring-5.5-20191226' of git://git.kernel.dk/linux-block:
  io-wq: add cond_resched() to worker thread
  io-wq: remove unused busy list from io_sqe
  io_uring: pass in 'sqe' to the prep handlers
  io_uring: standardize the prep methods
  io_uring: read 'count' for IORING_OP_TIMEOUT in prep handler
  io_uring: move all prep state for IORING_OP_{SEND,RECV}_MGS to prep handler
  io_uring: move all prep state for IORING_OP_CONNECT to prep handler
  io_uring: add and use struct io_rw for read/writes
  io_uring: use u64_to_user_ptr() consistently

2 files changed, 357 insertions, 343 deletions

diff --git a/fs/io-wq.c b/fs/io-wq.c
index 11e80b7252a8..541c8a3e0bbb 100644
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -92,7 +92,6 @@ struct io_wqe {
 	struct io_wqe_acct acct[2];
 
 	struct hlist_nulls_head free_list;
-	struct hlist_nulls_head busy_list;
 	struct list_head all_list;
 
 	struct io_wq *wq;
@@ -327,7 +326,6 @@ static void __io_worker_busy(struct io_wqe *wqe, struct io_worker *worker,
 	if (worker->flags & IO_WORKER_F_FREE) {
 		worker->flags &= ~IO_WORKER_F_FREE;
 		hlist_nulls_del_init_rcu(&worker->nulls_node);
-		hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->busy_list);
 	}
 
 	/*
@@ -365,7 +363,6 @@ static bool __io_worker_idle(struct io_wqe *wqe, struct io_worker *worker)
 {
 	if (!(worker->flags & IO_WORKER_F_FREE)) {
 		worker->flags |= IO_WORKER_F_FREE;
-		hlist_nulls_del_init_rcu(&worker->nulls_node);
 		hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list);
 	}
 
@@ -432,6 +429,8 @@ next:
 		if (signal_pending(current))
 			flush_signals(current);
 
+		cond_resched();
+
 		spin_lock_irq(&worker->lock);
 		worker->cur_work = work;
 		spin_unlock_irq(&worker->lock);
@@ -798,10 +797,6 @@ void io_wq_cancel_all(struct io_wq *wq)
 
 	set_bit(IO_WQ_BIT_CANCEL, &wq->state);
 
-	/*
-	 * Browse both lists, as there's a gap between handing work off
-	 * to a worker and the worker putting itself on the busy_list
-	 */
 	rcu_read_lock();
 	for_each_node(node) {
 		struct io_wqe *wqe = wq->wqes[node];
@@ -1049,7 +1044,6 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data)
 		spin_lock_init(&wqe->lock);
 		INIT_WQ_LIST(&wqe->work_list);
 		INIT_HLIST_NULLS_HEAD(&wqe->free_list, 0);
-		INIT_HLIST_NULLS_HEAD(&wqe->busy_list, 1);
 		INIT_LIST_HEAD(&wqe->all_list);
 	}
 
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 6f084e3cf835..562e3a1a1bf9 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -330,6 +330,26 @@ struct io_timeout {
 	struct file			*file;
 	u64				addr;
 	int				flags;
+	unsigned			count;
+};
+
+struct io_rw {
+	/* NOTE: kiocb has the file as the first member, so don't do it here */
+	struct kiocb			kiocb;
+	u64				addr;
+	u64				len;
+};
+
+struct io_connect {
+	struct file			*file;
+	struct sockaddr __user		*addr;
+	int				addr_len;
+};
+
+struct io_sr_msg {
+	struct file			*file;
+	struct user_msghdr __user	*msg;
+	int				msg_flags;
 };
 
 struct io_async_connect {
@@ -351,7 +371,6 @@ struct io_async_rw {
 };
 
 struct io_async_ctx {
-	struct io_uring_sqe		sqe;
 	union {
 		struct io_async_rw	rw;
 		struct io_async_msghdr	msg;
@@ -369,15 +388,16 @@ struct io_async_ctx {
 struct io_kiocb {
 	union {
 		struct file		*file;
-		struct kiocb		rw;
+		struct io_rw		rw;
 		struct io_poll_iocb	poll;
 		struct io_accept	accept;
 		struct io_sync		sync;
 		struct io_cancel	cancel;
 		struct io_timeout	timeout;
+		struct io_connect	connect;
+		struct io_sr_msg	sr_msg;
 	};
 
-	const struct io_uring_sqe	*sqe;
 	struct io_async_ctx		*io;
 	struct file			*ring_file;
 	int				ring_fd;
@@ -411,7 +431,6 @@ struct io_kiocb {
 #define REQ_F_INFLIGHT		16384	/* on inflight list */
 #define REQ_F_COMP_LOCKED	32768	/* completion under lock */
 #define REQ_F_HARDLINK		65536	/* doesn't sever on completion < 0 */
-#define REQ_F_PREPPED		131072	/* request already opcode prepared */
 	u64			user_data;
 	u32			result;
 	u32			sequence;
@@ -609,33 +628,31 @@ static inline bool io_prep_async_work(struct io_kiocb *req,
 {
 	bool do_hashed = false;
 
-	if (req->sqe) {
-		switch (req->opcode) {
-		case IORING_OP_WRITEV:
-		case IORING_OP_WRITE_FIXED:
-			/* only regular files should be hashed for writes */
-			if (req->flags & REQ_F_ISREG)
-				do_hashed = true;
-			/* fall-through */
-		case IORING_OP_READV:
-		case IORING_OP_READ_FIXED:
-		case IORING_OP_SENDMSG:
-		case IORING_OP_RECVMSG:
-		case IORING_OP_ACCEPT:
-		case IORING_OP_POLL_ADD:
-		case IORING_OP_CONNECT:
-			/*
-			 * We know REQ_F_ISREG is not set on some of these
-			 * opcodes, but this enables us to keep the check in
-			 * just one place.
-			 */
-			if (!(req->flags & REQ_F_ISREG))
-				req->work.flags |= IO_WQ_WORK_UNBOUND;
-			break;
-		}
-		if (io_req_needs_user(req))
-			req->work.flags |= IO_WQ_WORK_NEEDS_USER;
+	switch (req->opcode) {
+	case IORING_OP_WRITEV:
+	case IORING_OP_WRITE_FIXED:
+		/* only regular files should be hashed for writes */
+		if (req->flags & REQ_F_ISREG)
+			do_hashed = true;
+		/* fall-through */
+	case IORING_OP_READV:
+	case IORING_OP_READ_FIXED:
+	case IORING_OP_SENDMSG:
+	case IORING_OP_RECVMSG:
+	case IORING_OP_ACCEPT:
+	case IORING_OP_POLL_ADD:
+	case IORING_OP_CONNECT:
+		/*
+		 * We know REQ_F_ISREG is not set on some of these
+		 * opcodes, but this enables us to keep the check in
+		 * just one place.
+		 */
+		if (!(req->flags & REQ_F_ISREG))
+			req->work.flags |= IO_WQ_WORK_UNBOUND;
+		break;
 	}
+	if (io_req_needs_user(req))
+		req->work.flags |= IO_WQ_WORK_NEEDS_USER;
 
 	*link = io_prep_linked_timeout(req);
 	return do_hashed;
@@ -1180,7 +1197,7 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
 
 	ret = 0;
 	list_for_each_entry_safe(req, tmp, &ctx->poll_list, list) {
-		struct kiocb *kiocb = &req->rw;
+		struct kiocb *kiocb = &req->rw.kiocb;
 
 		/*
 		 * Move completed entries to our local list. If we find a
@@ -1335,7 +1352,7 @@ static inline void req_set_fail_links(struct io_kiocb *req)
 
 static void io_complete_rw_common(struct kiocb *kiocb, long res)
 {
-	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw);
+	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
 
 	if (kiocb->ki_flags & IOCB_WRITE)
 		kiocb_end_write(req);
@@ -1347,7 +1364,7 @@ static void io_complete_rw_common(struct kiocb *kiocb, long res)
 
 static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
 {
-	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw);
+	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
 
 	io_complete_rw_common(kiocb, res);
 	io_put_req(req);
@@ -1355,7 +1372,7 @@ static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
 
 static struct io_kiocb *__io_complete_rw(struct kiocb *kiocb, long res)
 {
-	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw);
+	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
 	struct io_kiocb *nxt = NULL;
 
 	io_complete_rw_common(kiocb, res);
@@ -1366,7 +1383,7 @@ static struct io_kiocb *__io_complete_rw(struct kiocb *kiocb, long res)
 
 static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
 {
-	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw);
+	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
 
 	if (kiocb->ki_flags & IOCB_WRITE)
 		kiocb_end_write(req);
@@ -1400,7 +1417,7 @@ static void io_iopoll_req_issued(struct io_kiocb *req)
 
 		list_req = list_first_entry(&ctx->poll_list, struct io_kiocb,
 						list);
-		if (list_req->rw.ki_filp != req->rw.ki_filp)
+		if (list_req->file != req->file)
 			ctx->poll_multi_file = true;
 	}
 
@@ -1471,11 +1488,11 @@ static bool io_file_supports_async(struct file *file)
 	return false;
 }
 
-static int io_prep_rw(struct io_kiocb *req, bool force_nonblock)
+static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+		      bool force_nonblock)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_ring_ctx *ctx = req->ctx;
-	struct kiocb *kiocb = &req->rw;
+	struct kiocb *kiocb = &req->rw.kiocb;
 	unsigned ioprio;
 	int ret;
 
@@ -1524,6 +1541,12 @@ static int io_prep_rw(struct io_kiocb *req, bool force_nonblock)
 			return -EINVAL;
 		kiocb->ki_complete = io_complete_rw;
 	}
+
+	req->rw.addr = READ_ONCE(sqe->addr);
+	req->rw.len = READ_ONCE(sqe->len);
+	/* we own ->private, reuse it for the buffer index */
+	req->rw.kiocb.private = (void *) (unsigned long)
+					READ_ONCE(sqe->buf_index);
 	return 0;
 }
 
@@ -1557,11 +1580,11 @@ static void kiocb_done(struct kiocb *kiocb, ssize_t ret, struct io_kiocb **nxt,
 		io_rw_done(kiocb, ret);
 }
 
-static ssize_t io_import_fixed(struct io_ring_ctx *ctx, int rw,
-			       const struct io_uring_sqe *sqe,
+static ssize_t io_import_fixed(struct io_kiocb *req, int rw,
 			       struct iov_iter *iter)
 {
-	size_t len = READ_ONCE(sqe->len);
+	struct io_ring_ctx *ctx = req->ctx;
+	size_t len = req->rw.len;
 	struct io_mapped_ubuf *imu;
 	unsigned index, buf_index;
 	size_t offset;
@@ -1571,13 +1594,13 @@ static ssize_t io_import_fixed(struct io_ring_ctx *ctx, int rw,
 	if (unlikely(!ctx->user_bufs))
 		return -EFAULT;
 
-	buf_index = READ_ONCE(sqe->buf_index);
+	buf_index = (unsigned long) req->rw.kiocb.private;
 	if (unlikely(buf_index >= ctx->nr_user_bufs))
 		return -EFAULT;
 
 	index = array_index_nospec(buf_index, ctx->nr_user_bufs);
 	imu = &ctx->user_bufs[index];
-	buf_addr = READ_ONCE(sqe->addr);
+	buf_addr = req->rw.addr;
 
 	/* overflow */
 	if (buf_addr + len < buf_addr)
@@ -1634,25 +1657,20 @@ static ssize_t io_import_fixed(struct io_ring_ctx *ctx, int rw,
 static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
 			       struct iovec **iovec, struct iov_iter *iter)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
-	void __user *buf = u64_to_user_ptr(READ_ONCE(sqe->addr));
-	size_t sqe_len = READ_ONCE(sqe->len);
+	void __user *buf = u64_to_user_ptr(req->rw.addr);
+	size_t sqe_len = req->rw.len;
 	u8 opcode;
 
-	/*
-	 * We're reading ->opcode for the second time, but the first read
-	 * doesn't care whether it's _FIXED or not, so it doesn't matter
-	 * whether ->opcode changes concurrently. The first read does care
-	 * about whether it is a READ or a WRITE, so we don't trust this read
-	 * for that purpose and instead let the caller pass in the read/write
-	 * flag.
-	 */
 	opcode = req->opcode;
 	if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
 		*iovec = NULL;
-		return io_import_fixed(req->ctx, rw, sqe, iter);
+		return io_import_fixed(req, rw, iter);
 	}
 
+	/* buffer index only valid with fixed read/write */
+	if (req->rw.kiocb.private)
+		return -EINVAL;
+
 	if (req->io) {
 		struct io_async_rw *iorw = &req->io->rw;
 
@@ -1750,13 +1768,7 @@ static void io_req_map_rw(struct io_kiocb *req, ssize_t io_size,
 static int io_alloc_async_ctx(struct io_kiocb *req)
 {
 	req->io = kmalloc(sizeof(*req->io), GFP_KERNEL);
-	if (req->io) {
-		memcpy(&req->io->sqe, req->sqe, sizeof(req->io->sqe));
-		req->sqe = &req->io->sqe;
-		return 0;
-	}
-
-	return 1;
+	return req->io == NULL;
 }
 
 static void io_rw_async(struct io_wq_work **workptr)
@@ -1782,46 +1794,52 @@ static int io_setup_async_rw(struct io_kiocb *req, ssize_t io_size,
 	return 0;
 }
 
-static int io_read_prep(struct io_kiocb *req, struct iovec **iovec,
-			struct iov_iter *iter, bool force_nonblock)
+static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+			bool force_nonblock)
 {
+	struct io_async_ctx *io;
+	struct iov_iter iter;
 	ssize_t ret;
 
-	ret = io_prep_rw(req, force_nonblock);
+	ret = io_prep_rw(req, sqe, force_nonblock);
 	if (ret)
 		return ret;
 
 	if (unlikely(!(req->file->f_mode & FMODE_READ)))
 		return -EBADF;
 
-	return io_import_iovec(READ, req, iovec, iter);
+	if (!req->io)
+		return 0;
+
+	io = req->io;
+	io->rw.iov = io->rw.fast_iov;
+	req->io = NULL;
+	ret = io_import_iovec(READ, req, &io->rw.iov, &iter);
+	req->io = io;
+	if (ret < 0)
+		return ret;
+
+	io_req_map_rw(req, ret, io->rw.iov, io->rw.fast_iov, &iter);
+	return 0;
 }
 
 static int io_read(struct io_kiocb *req, struct io_kiocb **nxt,
 		   bool force_nonblock)
 {
 	struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
-	struct kiocb *kiocb = &req->rw;
+	struct kiocb *kiocb = &req->rw.kiocb;
 	struct iov_iter iter;
-	struct file *file;
 	size_t iov_count;
 	ssize_t io_size, ret;
 
-	if (!req->io) {
-		ret = io_read_prep(req, &iovec, &iter, force_nonblock);
-		if (ret < 0)
-			return ret;
-	} else {
-		ret = io_import_iovec(READ, req, &iovec, &iter);
-		if (ret < 0)
-			return ret;
-	}
+	ret = io_import_iovec(READ, req, &iovec, &iter);
+	if (ret < 0)
+		return ret;
 
 	/* Ensure we clear previously set non-block flag */
 	if (!force_nonblock)
-		req->rw.ki_flags &= ~IOCB_NOWAIT;
+		req->rw.kiocb.ki_flags &= ~IOCB_NOWAIT;
 
-	file = req->file;
 	io_size = ret;
 	if (req->flags & REQ_F_LINK)
 		req->result = io_size;
@@ -1830,20 +1848,20 @@ static int io_read(struct io_kiocb *req, struct io_kiocb **nxt,
 	 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
 	 * we know to async punt it even if it was opened O_NONBLOCK
 	 */
-	if (force_nonblock && !io_file_supports_async(file)) {
+	if (force_nonblock && !io_file_supports_async(req->file)) {
 		req->flags |= REQ_F_MUST_PUNT;
 		goto copy_iov;
 	}
 
 	iov_count = iov_iter_count(&iter);
-	ret = rw_verify_area(READ, file, &kiocb->ki_pos, iov_count);
+	ret = rw_verify_area(READ, req->file, &kiocb->ki_pos, iov_count);
 	if (!ret) {
 		ssize_t ret2;
 
-		if (file->f_op->read_iter)
-			ret2 = call_read_iter(file, kiocb, &iter);
+		if (req->file->f_op->read_iter)
+			ret2 = call_read_iter(req->file, kiocb, &iter);
 		else
-			ret2 = loop_rw_iter(READ, file, kiocb, &iter);
+			ret2 = loop_rw_iter(READ, req->file, kiocb, &iter);
 
 		/*
 		 * In case of a short read, punt to async. This can happen
@@ -1875,46 +1893,52 @@ out_free:
 	return ret;
 }
 
-static int io_write_prep(struct io_kiocb *req, struct iovec **iovec,
-			 struct iov_iter *iter, bool force_nonblock)
+static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+			 bool force_nonblock)
 {
+	struct io_async_ctx *io;
+	struct iov_iter iter;
 	ssize_t ret;
 
-	ret = io_prep_rw(req, force_nonblock);
+	ret = io_prep_rw(req, sqe, force_nonblock);
 	if (ret)
 		return ret;
 
 	if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
 		return -EBADF;
 
-	return io_import_iovec(WRITE, req, iovec, iter);
+	if (!req->io)
+		return 0;
+
+	io = req->io;
+	io->rw.iov = io->rw.fast_iov;
+	req->io = NULL;
+	ret = io_import_iovec(WRITE, req, &io->rw.iov, &iter);
+	req->io = io;
+	if (ret < 0)
+		return ret;
+
+	io_req_map_rw(req, ret, io->rw.iov, io->rw.fast_iov, &iter);
+	return 0;
 }
 
 static int io_write(struct io_kiocb *req, struct io_kiocb **nxt,
 		    bool force_nonblock)
 {
 	struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
-	struct kiocb *kiocb = &req->rw;
+	struct kiocb *kiocb = &req->rw.kiocb;
 	struct iov_iter iter;
-	struct file *file;
 	size_t iov_count;
 	ssize_t ret, io_size;
 
-	if (!req->io) {
-		ret = io_write_prep(req, &iovec, &iter, force_nonblock);
-		if (ret < 0)
-			return ret;
-	} else {
-		ret = io_import_iovec(WRITE, req, &iovec, &iter);
-		if (ret < 0)
-			return ret;
-	}
+	ret = io_import_iovec(WRITE, req, &iovec, &iter);
+	if (ret < 0)
+		return ret;
 
 	/* Ensure we clear previously set non-block flag */
 	if (!force_nonblock)
-		req->rw.ki_flags &= ~IOCB_NOWAIT;
+		req->rw.kiocb.ki_flags &= ~IOCB_NOWAIT;
 
-	file = kiocb->ki_filp;
 	io_size = ret;
 	if (req->flags & REQ_F_LINK)
 		req->result = io_size;
@@ -1934,7 +1958,7 @@ static int io_write(struct io_kiocb *req, struct io_kiocb **nxt,
 		goto copy_iov;
 
 	iov_count = iov_iter_count(&iter);
-	ret = rw_verify_area(WRITE, file, &kiocb->ki_pos, iov_count);
+	ret = rw_verify_area(WRITE, req->file, &kiocb->ki_pos, iov_count);
 	if (!ret) {
 		ssize_t ret2;
 
@@ -1946,17 +1970,17 @@ static int io_write(struct io_kiocb *req, struct io_kiocb **nxt,
 		 * we return to userspace.
 		 */
 		if (req->flags & REQ_F_ISREG) {
-			__sb_start_write(file_inode(file)->i_sb,
+			__sb_start_write(file_inode(req->file)->i_sb,
 						SB_FREEZE_WRITE, true);
-			__sb_writers_release(file_inode(file)->i_sb,
+			__sb_writers_release(file_inode(req->file)->i_sb,
 						SB_FREEZE_WRITE);
 		}
 		kiocb->ki_flags |= IOCB_WRITE;
 
-		if (file->f_op->write_iter)
-			ret2 = call_write_iter(file, kiocb, &iter);
+		if (req->file->f_op->write_iter)
+			ret2 = call_write_iter(req->file, kiocb, &iter);
 		else
-			ret2 = loop_rw_iter(WRITE, file, kiocb, &iter);
+			ret2 = loop_rw_iter(WRITE, req->file, kiocb, &iter);
 		if (!force_nonblock || ret2 != -EAGAIN) {
 			kiocb_done(kiocb, ret2, nxt, req->in_async);
 		} else {
@@ -1989,13 +2013,10 @@ static int io_nop(struct io_kiocb *req)
 	return 0;
 }
 
-static int io_prep_fsync(struct io_kiocb *req)
+static int io_prep_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_ring_ctx *ctx = req->ctx;
 
-	if (req->flags & REQ_F_PREPPED)
-		return 0;
 	if (!req->file)
 		return -EBADF;
 
@@ -2010,7 +2031,6 @@ static int io_prep_fsync(struct io_kiocb *req)
 
 	req->sync.off = READ_ONCE(sqe->off);
 	req->sync.len = READ_ONCE(sqe->len);
-	req->flags |= REQ_F_PREPPED;
 	return 0;
 }
 
@@ -2036,7 +2056,7 @@ static void io_fsync_finish(struct io_wq_work **workptr)
 	if (io_req_cancelled(req))
 		return;
 
-	ret = vfs_fsync_range(req->rw.ki_filp, req->sync.off,
+	ret = vfs_fsync_range(req->file, req->sync.off,
 				end > 0 ? end : LLONG_MAX,
 				req->sync.flags & IORING_FSYNC_DATASYNC);
 	if (ret < 0)
@@ -2051,11 +2071,6 @@ static int io_fsync(struct io_kiocb *req, struct io_kiocb **nxt,
 		    bool force_nonblock)
 {
 	struct io_wq_work *work, *old_work;
-	int ret;
-
-	ret = io_prep_fsync(req);
-	if (ret)
-		return ret;
 
 	/* fsync always requires a blocking context */
 	if (force_nonblock) {
@@ -2071,13 +2086,10 @@ static int io_fsync(struct io_kiocb *req, struct io_kiocb **nxt,
 	return 0;
 }
 
-static int io_prep_sfr(struct io_kiocb *req)
+static int io_prep_sfr(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_ring_ctx *ctx = req->ctx;
 
-	if (req->flags & REQ_F_PREPPED)
-		return 0;
 	if (!req->file)
 		return -EBADF;
 
@@ -2089,7 +2101,6 @@ static int io_prep_sfr(struct io_kiocb *req)
 	req->sync.off = READ_ONCE(sqe->off);
 	req->sync.len = READ_ONCE(sqe->len);
 	req->sync.flags = READ_ONCE(sqe->sync_range_flags);
-	req->flags |= REQ_F_PREPPED;
 	return 0;
 }
 
@@ -2102,7 +2113,7 @@ static void io_sync_file_range_finish(struct io_wq_work **workptr)
 	if (io_req_cancelled(req))
 		return;
 
-	ret = sync_file_range(req->rw.ki_filp, req->sync.off, req->sync.len,
+	ret = sync_file_range(req->file, req->sync.off, req->sync.len,
 				req->sync.flags);
 	if (ret < 0)
 		req_set_fail_links(req);
@@ -2116,11 +2127,6 @@ static int io_sync_file_range(struct io_kiocb *req, struct io_kiocb **nxt,
 			      bool force_nonblock)
 {
 	struct io_wq_work *work, *old_work;
-	int ret;
-
-	ret = io_prep_sfr(req);
-	if (ret)
-		return ret;
 
 	/* sync_file_range always requires a blocking context */
 	if (force_nonblock) {
@@ -2149,19 +2155,23 @@ static void io_sendrecv_async(struct io_wq_work **workptr)
 }
 #endif
 
-static int io_sendmsg_prep(struct io_kiocb *req, struct io_async_ctx *io)
+static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 #if defined(CONFIG_NET)
-	const struct io_uring_sqe *sqe = req->sqe;
-	struct user_msghdr __user *msg;
-	unsigned flags;
+	struct io_sr_msg *sr = &req->sr_msg;
+	struct io_async_ctx *io = req->io;
+
+	sr->msg_flags = READ_ONCE(sqe->msg_flags);
+	sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr));
+
+	if (!io)
+		return 0;
 
-	flags = READ_ONCE(sqe->msg_flags);
-	msg = (struct user_msghdr __user *)(unsigned long) READ_ONCE(sqe->addr);
 	io->msg.iov = io->msg.fast_iov;
-	return sendmsg_copy_msghdr(&io->msg.msg, msg, flags, &io->msg.iov);
+	return sendmsg_copy_msghdr(&io->msg.msg, sr->msg, sr->msg_flags,
+					&io->msg.iov);
 #else
-	return 0;
+	return -EOPNOTSUPP;
 #endif
 }
 
@@ -2169,7 +2179,6 @@ static int io_sendmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 		      bool force_nonblock)
 {
 #if defined(CONFIG_NET)
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_async_msghdr *kmsg = NULL;
 	struct socket *sock;
 	int ret;
@@ -2183,12 +2192,6 @@ static int io_sendmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 		struct sockaddr_storage addr;
 		unsigned flags;
 
-		flags = READ_ONCE(sqe->msg_flags);
-		if (flags & MSG_DONTWAIT)
-			req->flags |= REQ_F_NOWAIT;
-		else if (force_nonblock)
-			flags |= MSG_DONTWAIT;
-
 		if (req->io) {
 			kmsg = &req->io->msg;
 			kmsg->msg.msg_name = &addr;
@@ -2197,13 +2200,24 @@ static int io_sendmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 				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 = &addr;
-			ret = io_sendmsg_prep(req, &io);
+
+			io.msg.iov = io.msg.fast_iov;
+			ret = sendmsg_copy_msghdr(&io.msg.msg, sr->msg,
+					sr->msg_flags, &io.msg.iov);
 			if (ret)
-				goto out;
+				return ret;
 		}
 
+		flags = req->sr_msg.msg_flags;
+		if (flags & MSG_DONTWAIT)
+			req->flags |= REQ_F_NOWAIT;
+		else if (force_nonblock)
+			flags |= MSG_DONTWAIT;
+
 		ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
 		if (force_nonblock && ret == -EAGAIN) {
 			if (req->io)
@@ -2218,7 +2232,6 @@ static int io_sendmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 			ret = -EINTR;
 	}
 
-out:
 	if (!io_wq_current_is_worker() && kmsg && kmsg->iov != kmsg->fast_iov)
 		kfree(kmsg->iov);
 	io_cqring_add_event(req, ret);
@@ -2231,20 +2244,24 @@ out:
 #endif
 }
 
-static int io_recvmsg_prep(struct io_kiocb *req, struct io_async_ctx *io)
+static int io_recvmsg_prep(struct io_kiocb *req,
+			   const struct io_uring_sqe *sqe)
 {
 #if defined(CONFIG_NET)
-	const struct io_uring_sqe *sqe = req->sqe;
-	struct user_msghdr __user *msg;
-	unsigned flags;
+	struct io_sr_msg *sr = &req->sr_msg;
+	struct io_async_ctx *io = req->io;
+
+	sr->msg_flags = READ_ONCE(sqe->msg_flags);
+	sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr));
+
+	if (!io)
+		return 0;
 
-	flags = READ_ONCE(sqe->msg_flags);
-	msg = (struct user_msghdr __user *)(unsigned long) READ_ONCE(sqe->addr);
 	io->msg.iov = io->msg.fast_iov;
-	return recvmsg_copy_msghdr(&io->msg.msg, msg, flags, &io->msg.uaddr,
-					&io->msg.iov);
+	return recvmsg_copy_msghdr(&io->msg.msg, sr->msg, sr->msg_flags,
+					&io->msg.uaddr, &io->msg.iov);
 #else
-	return 0;
+	return -EOPNOTSUPP;
 #endif
 }
 
@@ -2252,7 +2269,6 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 		      bool force_nonblock)
 {
 #if defined(CONFIG_NET)
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_async_msghdr *kmsg = NULL;
 	struct socket *sock;
 	int ret;
@@ -2262,19 +2278,10 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 
 	sock = sock_from_file(req->file, &ret);
 	if (sock) {
-		struct user_msghdr __user *msg;
 		struct io_async_ctx io;
 		struct sockaddr_storage addr;
 		unsigned flags;
 
-		flags = READ_ONCE(sqe->msg_flags);
-		if (flags & MSG_DONTWAIT)
-			req->flags |= REQ_F_NOWAIT;
-		else if (force_nonblock)
-			flags |= MSG_DONTWAIT;
-
-		msg = (struct user_msghdr __user *) (unsigned long)
-			READ_ONCE(sqe->addr);
 		if (req->io) {
 			kmsg = &req->io->msg;
 			kmsg->msg.msg_name = &addr;
@@ -2283,14 +2290,27 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 				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 = &addr;
-			ret = io_recvmsg_prep(req, &io);
+
+			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);
 			if (ret)
-				goto out;
+				return ret;
 		}
 
-		ret = __sys_recvmsg_sock(sock, &kmsg->msg, msg, kmsg->uaddr, flags);
+		flags = req->sr_msg.msg_flags;
+		if (flags & MSG_DONTWAIT)
+			req->flags |= REQ_F_NOWAIT;
+		else if (force_nonblock)
+			flags |= MSG_DONTWAIT;
+
+		ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.msg,
+						kmsg->uaddr, flags);
 		if (force_nonblock && ret == -EAGAIN) {
 			if (req->io)
 				return -EAGAIN;
@@ -2304,7 +2324,6 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt,
 			ret = -EINTR;
 	}
 
-out:
 	if (!io_wq_current_is_worker() && kmsg && kmsg->iov != kmsg->fast_iov)
 		kfree(kmsg->iov);
 	io_cqring_add_event(req, ret);
@@ -2317,25 +2336,19 @@ out:
 #endif
 }
 
-static int io_accept_prep(struct io_kiocb *req)
+static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 #if defined(CONFIG_NET)
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_accept *accept = &req->accept;
 
-	if (req->flags & REQ_F_PREPPED)
-		return 0;
-
 	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
 		return -EINVAL;
 	if (sqe->ioprio || sqe->len || sqe->buf_index)
 		return -EINVAL;
 
-	accept->addr = (struct sockaddr __user *)
-				(unsigned long) READ_ONCE(sqe->addr);
-	accept->addr_len = (int __user *) (unsigned long) READ_ONCE(sqe->addr2);
+	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
+	accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
 	accept->flags = READ_ONCE(sqe->accept_flags);
-	req->flags |= REQ_F_PREPPED;
 	return 0;
 #else
 	return -EOPNOTSUPP;
@@ -2383,10 +2396,6 @@ static int io_accept(struct io_kiocb *req, struct io_kiocb **nxt,
 #if defined(CONFIG_NET)
 	int ret;
 
-	ret = io_accept_prep(req);
-	if (ret)
-		return ret;
-
 	ret = __io_accept(req, nxt, force_nonblock);
 	if (ret == -EAGAIN && force_nonblock) {
 		req->work.func = io_accept_finish;
@@ -2400,18 +2409,27 @@ static int io_accept(struct io_kiocb *req, struct io_kiocb **nxt,
 #endif
 }
 
-static int io_connect_prep(struct io_kiocb *req, struct io_async_ctx *io)
+static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 #if defined(CONFIG_NET)
-	const struct io_uring_sqe *sqe = req->sqe;
-	struct sockaddr __user *addr;
-	int addr_len;
+	struct io_connect *conn = &req->connect;
+	struct io_async_ctx *io = req->io;
+
+	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+		return -EINVAL;
+	if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags)
+		return -EINVAL;
 
-	addr = (struct sockaddr __user *) (unsigned long) READ_ONCE(sqe->addr);
-	addr_len = READ_ONCE(sqe->addr2);
-	return move_addr_to_kernel(addr, addr_len, &io->connect.address);
+	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
+	conn->addr_len =  READ_ONCE(sqe->addr2);
+
+	if (!io)
+		return 0;
+
+	return move_addr_to_kernel(conn->addr, conn->addr_len,
+					&io->connect.address);
 #else
-	return 0;
+	return -EOPNOTSUPP;
 #endif
 }
 
@@ -2419,30 +2437,25 @@ static int io_connect(struct io_kiocb *req, struct io_kiocb **nxt,
 		      bool force_nonblock)
 {
 #if defined(CONFIG_NET)
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_async_ctx __io, *io;
 	unsigned file_flags;
-	int addr_len, ret;
-
-	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
-		return -EINVAL;
-	if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags)
-		return -EINVAL;
-
-	addr_len = READ_ONCE(sqe->addr2);
-	file_flags = force_nonblock ? O_NONBLOCK : 0;
+	int ret;
 
 	if (req->io) {
 		io = req->io;
 	} else {
-		ret = io_connect_prep(req, &__io);
+		ret = move_addr_to_kernel(req->connect.addr,
+						req->connect.addr_len,
+						&__io.connect.address);
 		if (ret)
 			goto out;
 		io = &__io;
 	}
 
-	ret = __sys_connect_file(req->file, &io->connect.address, addr_len,
-					file_flags);
+	file_flags = force_nonblock ? O_NONBLOCK : 0;
+
+	ret = __sys_connect_file(req->file, &io->connect.address,
+					req->connect.addr_len, file_flags);
 	if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
 		if (req->io)
 			return -EAGAIN;
@@ -2513,12 +2526,9 @@ static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr)
 	return -ENOENT;
 }
 
-static int io_poll_remove_prep(struct io_kiocb *req)
+static int io_poll_remove_prep(struct io_kiocb *req,
+			       const struct io_uring_sqe *sqe)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
-
-	if (req->flags & REQ_F_PREPPED)
-		return 0;
 	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
 		return -EINVAL;
 	if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
@@ -2526,7 +2536,6 @@ static int io_poll_remove_prep(struct io_kiocb *req)
 		return -EINVAL;
 
 	req->poll.addr = READ_ONCE(sqe->addr);
-	req->flags |= REQ_F_PREPPED;
 	return 0;
 }
 
@@ -2540,10 +2549,6 @@ static int io_poll_remove(struct io_kiocb *req)
 	u64 addr;
 	int ret;
 
-	ret = io_poll_remove_prep(req);
-	if (ret)
-		return ret;
-
 	addr = req->poll.addr;
 	spin_lock_irq(&ctx->completion_lock);
 	ret = io_poll_cancel(ctx, addr);
@@ -2681,14 +2686,11 @@ static void io_poll_req_insert(struct io_kiocb *req)
 	hlist_add_head(&req->hash_node, list);
 }
 
-static int io_poll_add_prep(struct io_kiocb *req)
+static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_poll_iocb *poll = &req->poll;
 	u16 events;
 
-	if (req->flags & REQ_F_PREPPED)
-		return 0;
 	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
 		return -EINVAL;
 	if (sqe->addr || sqe->ioprio || sqe->off || sqe->len || sqe->buf_index)
@@ -2696,7 +2698,6 @@ static int io_poll_add_prep(struct io_kiocb *req)
 	if (!poll->file)
 		return -EBADF;
 
-	req->flags |= REQ_F_PREPPED;
 	events = READ_ONCE(sqe->poll_events);
 	poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP;
 	return 0;
@@ -2709,11 +2710,6 @@ static int io_poll_add(struct io_kiocb *req, struct io_kiocb **nxt)
 	struct io_poll_table ipt;
 	bool cancel = false;
 	__poll_t mask;
-	int ret;
-
-	ret = io_poll_add_prep(req);
-	if (ret)
-		return ret;
 
 	INIT_IO_WORK(&req->work, io_poll_complete_work);
 	INIT_HLIST_NODE(&req->hash_node);
@@ -2832,12 +2828,9 @@ static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
 	return 0;
 }
 
-static int io_timeout_remove_prep(struct io_kiocb *req)
+static int io_timeout_remove_prep(struct io_kiocb *req,
+				  const struct io_uring_sqe *sqe)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
-
-	if (req->flags & REQ_F_PREPPED)
-		return 0;
 	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
 		return -EINVAL;
 	if (sqe->flags || sqe->ioprio || sqe->buf_index || sqe->len)
@@ -2848,7 +2841,6 @@ static int io_timeout_remove_prep(struct io_kiocb *req)
 	if (req->timeout.flags)
 		return -EINVAL;
 
-	req->flags |= REQ_F_PREPPED;
 	return 0;
 }
 
@@ -2860,10 +2852,6 @@ static int io_timeout_remove(struct io_kiocb *req)
 	struct io_ring_ctx *ctx = req->ctx;
 	int ret;
 
-	ret = io_timeout_remove_prep(req);
-	if (ret)
-		return ret;
-
 	spin_lock_irq(&ctx->completion_lock);
 	ret = io_timeout_cancel(ctx, req->timeout.addr);
 
@@ -2877,10 +2865,9 @@ static int io_timeout_remove(struct io_kiocb *req)
 	return 0;
 }
 
-static int io_timeout_prep(struct io_kiocb *req, struct io_async_ctx *io,
+static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
 			   bool is_timeout_link)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
 	struct io_timeout_data *data;
 	unsigned flags;
 
@@ -2894,7 +2881,12 @@ static int io_timeout_prep(struct io_kiocb *req, struct io_async_ctx *io,
 	if (flags & ~IORING_TIMEOUT_ABS)
 		return -EINVAL;
 
-	data = &io->timeout;
+	req->timeout.count = READ_ONCE(sqe->off);
+
+	if (!req->io && io_alloc_async_ctx(req))
+		return -ENOMEM;
+
+	data = &req->io->timeout;
 	data->req = req;
 	req->flags |= REQ_F_TIMEOUT;
 
@@ -2912,21 +2904,12 @@ static int io_timeout_prep(struct io_kiocb *req, struct io_async_ctx *io,
 
 static int io_timeout(struct io_kiocb *req)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
 	unsigned count;
 	struct io_ring_ctx *ctx = req->ctx;
 	struct io_timeout_data *data;
 	struct list_head *entry;
 	unsigned span = 0;
-	int ret;
 
-	if (!req->io) {
-		if (io_alloc_async_ctx(req))
-			return -ENOMEM;
-		ret = io_timeout_prep(req, req->io, false);
-		if (ret)
-			return ret;
-	}
 	data = &req->io->timeout;
 
 	/*
@@ -2934,7 +2917,7 @@ static int io_timeout(struct io_kiocb *req)
 	 * timeout event to be satisfied. If it isn't set, then this is
 	 * a pure timeout request, sequence isn't used.
 	 */
-	count = READ_ONCE(sqe->off);
+	count = req->timeout.count;
 	if (!count) {
 		req->flags |= REQ_F_TIMEOUT_NOSEQ;
 		spin_lock_irq(&ctx->completion_lock);
@@ -3052,19 +3035,15 @@ done:
 	io_put_req_find_next(req, nxt);
 }
 
-static int io_async_cancel_prep(struct io_kiocb *req)
+static int io_async_cancel_prep(struct io_kiocb *req,
+				const struct io_uring_sqe *sqe)
 {
-	const struct io_uring_sqe *sqe = req->sqe;
-
-	if (req->flags & REQ_F_PREPPED)
-		return 0;
 	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
 		return -EINVAL;
 	if (sqe->flags || sqe->ioprio || sqe->off || sqe->len ||
 	    sqe->cancel_flags)
 		return -EINVAL;
 
-	req->flags |= REQ_F_PREPPED;
 	req->cancel.addr = READ_ONCE(sqe->addr);
 	return 0;
 }
@@ -3072,21 +3051,14 @@ static int io_async_cancel_prep(struct io_kiocb *req)
 static int io_async_cancel(struct io_kiocb *req, struct io_kiocb **nxt)
 {
 	struct io_ring_ctx *ctx = req->ctx;
-	int ret;
-
-	ret = io_async_cancel_prep(req);
-	if (ret)
-		return ret;
 
 	io_async_find_and_cancel(ctx, req, req->cancel.addr, nxt, 0);
 	return 0;
 }
 
-static int io_req_defer_prep(struct io_kiocb *req)
+static int io_req_defer_prep(struct io_kiocb *req,
+			     const struct io_uring_sqe *sqe)
 {
-	struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
-	struct io_async_ctx *io = req->io;
-	struct iov_iter iter;
 	ssize_t ret = 0;
 
 	switch (req->opcode) {
@@ -3094,61 +3066,47 @@ static int io_req_defer_prep(struct io_kiocb *req)
 		break;
 	case IORING_OP_READV:
 	case IORING_OP_READ_FIXED:
-		/* ensure prep does right import */
-		req->io = NULL;
-		ret = io_read_prep(req, &iovec, &iter, true);
-		req->io = io;
-		if (ret < 0)
-			break;
-		io_req_map_rw(req, ret, iovec, inline_vecs, &iter);
-		ret = 0;
+		ret = io_read_prep(req, sqe, true);
 		break;
 	case IORING_OP_WRITEV:
 	case IORING_OP_WRITE_FIXED:
-		/* ensure prep does right import */
-		req->io = NULL;
-		ret = io_write_prep(req, &iovec, &iter, true);
-		req->io = io;
-		if (ret < 0)
-			break;
-		io_req_map_rw(req, ret, iovec, inline_vecs, &iter);
-		ret = 0;
+		ret = io_write_prep(req, sqe, true);
 		break;
 	case IORING_OP_POLL_ADD:
-		ret = io_poll_add_prep(req);
+		ret = io_poll_add_prep(req, sqe);
 		break;
 	case IORING_OP_POLL_REMOVE:
-		ret = io_poll_remove_prep(req);
+		ret = io_poll_remove_prep(req, sqe);
 		break;
 	case IORING_OP_FSYNC:
-		ret = io_prep_fsync(req);
+		ret = io_prep_fsync(req, sqe);
 		break;
 	case IORING_OP_SYNC_FILE_RANGE:
-		ret = io_prep_sfr(req);
+		ret = io_prep_sfr(req, sqe);
 		break;
 	case IORING_OP_SENDMSG:
-		ret = io_sendmsg_prep(req, io);
+		ret = io_sendmsg_prep(req, sqe);
 		break;
 	case IORING_OP_RECVMSG:
-		ret = io_recvmsg_prep(req, io);
+		ret = io_recvmsg_prep(req, sqe);
 		break;
 	case IORING_OP_CONNECT:
-		ret = io_connect_prep(req, io);
+		ret = io_connect_prep(req, sqe);
 		break;
 	case IORING_OP_TIMEOUT:
-		ret = io_timeout_prep(req, io, false);
+		ret = io_timeout_prep(req, sqe, false);
 		break;
 	case IORING_OP_TIMEOUT_REMOVE:
-		ret = io_timeout_remove_prep(req);
+		ret = io_timeout_remove_prep(req, sqe);
 		break;
 	case IORING_OP_ASYNC_CANCEL:
-		ret = io_async_cancel_prep(req);
+		ret = io_async_cancel_prep(req, sqe);
 		break;
 	case IORING_OP_LINK_TIMEOUT:
-		ret = io_timeout_prep(req, io, true);
+		ret = io_timeout_prep(req, sqe, true);
 		break;
 	case IORING_OP_ACCEPT:
-		ret = io_accept_prep(req);
+		ret = io_accept_prep(req, sqe);
 		break;
 	default:
 		printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
@@ -3160,7 +3118,7 @@ static int io_req_defer_prep(struct io_kiocb *req)
 	return ret;
 }
 
-static int io_req_defer(struct io_kiocb *req)
+static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	struct io_ring_ctx *ctx = req->ctx;
 	int ret;
@@ -3169,10 +3127,10 @@ static int io_req_defer(struct io_kiocb *req)
 	if (!req_need_defer(req) && list_empty(&ctx->defer_list))
 		return 0;
 
-	if (io_alloc_async_ctx(req))
+	if (!req->io && io_alloc_async_ctx(req))
 		return -EAGAIN;
 
-	ret = io_req_defer_prep(req);
+	ret = io_req_defer_prep(req, sqe);
 	if (ret < 0)
 		return ret;
 
@@ -3188,9 +3146,8 @@ static int io_req_defer(struct io_kiocb *req)
 	return -EIOCBQUEUED;
 }
 
-__attribute__((nonnull))
-static int io_issue_sqe(struct io_kiocb *req, struct io_kiocb **nxt,
-			bool force_nonblock)
+static int io_issue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+			struct io_kiocb **nxt, bool force_nonblock)
 {
 	struct io_ring_ctx *ctx = req->ctx;
 	int ret;
@@ -3200,52 +3157,109 @@ static int io_issue_sqe(struct io_kiocb *req, struct io_kiocb **nxt,
 		ret = io_nop(req);
 		break;
 	case IORING_OP_READV:
-		if (unlikely(req->sqe->buf_index))
-			return -EINVAL;
-		ret = io_read(req, nxt, force_nonblock);
-		break;
-	case IORING_OP_WRITEV:
-		if (unlikely(req->sqe->buf_index))
-			return -EINVAL;
-		ret = io_write(req, nxt, force_nonblock);
-		break;
 	case IORING_OP_READ_FIXED:
+		if (sqe) {
+			ret = io_read_prep(req, sqe, force_nonblock);
+			if (ret < 0)
+				break;
+		}
 		ret = io_read(req, nxt, force_nonblock);
 		break;
+	case IORING_OP_WRITEV:
 	case IORING_OP_WRITE_FIXED:
+		if (sqe) {
+			ret = io_write_prep(req, sqe, force_nonblock);
+			if (ret < 0)
+				break;
+		}
 		ret = io_write(req, nxt, force_nonblock);
 		break;
 	case IORING_OP_FSYNC:
+		if (sqe) {
+			ret = io_prep_fsync(req, sqe);
+			if (ret < 0)
+				break;
+		}
 		ret = io_fsync(req, nxt, force_nonblock);
 		break;
 	case IORING_OP_POLL_ADD:
+		if (sqe) {
+			ret = io_poll_add_prep(req, sqe);
+			if (ret)
+				break;
+		}
 		ret = io_poll_add(req, nxt);
 		break;
 	case IORING_OP_POLL_REMOVE:
+		if (sqe) {
+			ret = io_poll_remove_prep(req, sqe);
+			if (ret < 0)
+				break;
+		}
 		ret = io_poll_remove(req);
 		break;
 	case IORING_OP_SYNC_FILE_RANGE:
+		if (sqe) {
+			ret = io_prep_sfr(req, sqe);
+			if (ret < 0)
+				break;
+		}
 		ret = io_sync_file_range(req, nxt, force_nonblock);
 		break;
 	case IORING_OP_SENDMSG:
+		if (sqe) {
+			ret = io_sendmsg_prep(req, sqe);
+			if (ret < 0)
+				break;
+		}
 		ret = io_sendmsg(req, nxt, force_nonblock);
 		break;
 	case IORING_OP_RECVMSG:
+		if (sqe) {
+			ret = io_recvmsg_prep(req, sqe);
+			if (ret)
+				break;
+		}
 		ret = io_recvmsg(req, nxt, force_nonblock);
 		break;
 	case IORING_OP_TIMEOUT:
+		if (sqe) {
+			ret = io_timeout_prep(req, sqe, false);
+			if (ret)
+				break;
+		}
 		ret = io_timeout(req);
 		break;
 	case IORING_OP_TIMEOUT_REMOVE:
+		if (sqe) {
+			ret = io_timeout_remove_prep(req, sqe);
+			if (ret)
+				break;
+		}
 		ret = io_timeout_remove(req);
 		break;
 	case IORING_OP_ACCEPT:
+		if (sqe) {
+			ret = io_accept_prep(req, sqe);
+			if (ret)
+				break;
+		}
 		ret = io_accept(req, nxt, force_nonblock);
 		break;
 	case IORING_OP_CONNECT:
+		if (sqe) {
+			ret = io_connect_prep(req, sqe);
+			if (ret)
+				break;
+		}
 		ret = io_connect(req, nxt, force_nonblock);
 		break;
 	case IORING_OP_ASYNC_CANCEL:
+		if (sqe) {
+			ret = io_async_cancel_prep(req, sqe);
+			if (ret)
+				break;
+		}
 		ret = io_async_cancel(req, nxt);
 		break;
 	default:
@@ -3289,7 +3303,7 @@ static void io_wq_submit_work(struct io_wq_work **workptr)
 		req->has_user = (work->flags & IO_WQ_WORK_HAS_MM) != 0;
 		req->in_async = true;
 		do {
-			ret = io_issue_sqe(req, &nxt, false);
+			ret = io_issue_sqe(req, NULL, &nxt, false);
 			/*
 			 * We can get EAGAIN for polled IO even though we're
 			 * forcing a sync submission from here, since we can't
@@ -3355,14 +3369,15 @@ static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
 	return table->files[index & IORING_FILE_TABLE_MASK];
 }
 
-static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req)
+static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req,
+			   const struct io_uring_sqe *sqe)
 {
 	struct io_ring_ctx *ctx = req->ctx;
 	unsigned flags;
 	int fd, ret;
 
-	flags = READ_ONCE(req->sqe->flags);
-	fd = READ_ONCE(req->sqe->fd);
+	flags = READ_ONCE(sqe->flags);
+	fd = READ_ONCE(sqe->fd);
 
 	if (flags & IOSQE_IO_DRAIN)
 		req->flags |= REQ_F_IO_DRAIN;
@@ -3494,7 +3509,7 @@ static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
 	return nxt;
 }
 
-static void __io_queue_sqe(struct io_kiocb *req)
+static void __io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	struct io_kiocb *linked_timeout;
 	struct io_kiocb *nxt = NULL;
@@ -3503,7 +3518,7 @@ static void __io_queue_sqe(struct io_kiocb *req)
 again:
 	linked_timeout = io_prep_linked_timeout(req);
 
-	ret = io_issue_sqe(req, &nxt, true);
+	ret = io_issue_sqe(req, sqe, &nxt, true);
 
 	/*
 	 * We async punt it if the file wasn't marked NOWAIT, or if the file
@@ -3550,7 +3565,7 @@ done_req:
 	}
 }
 
-static void io_queue_sqe(struct io_kiocb *req)
+static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	int ret;
 
@@ -3560,7 +3575,7 @@ static void io_queue_sqe(struct io_kiocb *req)
 	}
 	req->ctx->drain_next = (req->flags & REQ_F_DRAIN_LINK);
 
-	ret = io_req_defer(req);
+	ret = io_req_defer(req, sqe);
 	if (ret) {
 		if (ret != -EIOCBQUEUED) {
 			io_cqring_add_event(req, ret);
@@ -3568,7 +3583,7 @@ static void io_queue_sqe(struct io_kiocb *req)
 			io_double_put_req(req);
 		}
 	} else
-		__io_queue_sqe(req);
+		__io_queue_sqe(req, sqe);
 }
 
 static inline void io_queue_link_head(struct io_kiocb *req)
@@ -3577,25 +3592,25 @@ static inline void io_queue_link_head(struct io_kiocb *req)
 		io_cqring_add_event(req, -ECANCELED);
 		io_double_put_req(req);
 	} else
-		io_queue_sqe(req);
+		io_queue_sqe(req, NULL);
 }
 
 #define SQE_VALID_FLAGS	(IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK|	\
 				IOSQE_IO_HARDLINK)
 
-static bool io_submit_sqe(struct io_kiocb *req, struct io_submit_state *state,
-			  struct io_kiocb **link)
+static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+			  struct io_submit_state *state, struct io_kiocb **link)
 {
 	struct io_ring_ctx *ctx = req->ctx;
 	int ret;
 
 	/* enforce forwards compatibility on users */
-	if (unlikely(req->sqe->flags & ~SQE_VALID_FLAGS)) {
+	if (unlikely(sqe->flags & ~SQE_VALID_FLAGS)) {
 		ret = -EINVAL;
 		goto err_req;
 	}
 
-	ret = io_req_set_file(state, req);
+	ret = io_req_set_file(state, req, sqe);
 	if (unlikely(ret)) {
 err_req:
 		io_cqring_add_event(req, ret);
@@ -3613,10 +3628,10 @@ err_req:
 	if (*link) {
 		struct io_kiocb *prev = *link;
 
-		if (req->sqe->flags & IOSQE_IO_DRAIN)
+		if (sqe->flags & IOSQE_IO_DRAIN)
 			(*link)->flags |= REQ_F_DRAIN_LINK | REQ_F_IO_DRAIN;
 
-		if (req->sqe->flags & IOSQE_IO_HARDLINK)
+		if (sqe->flags & IOSQE_IO_HARDLINK)
 			req->flags |= REQ_F_HARDLINK;
 
 		if (io_alloc_async_ctx(req)) {
@@ -3624,7 +3639,7 @@ err_req:
 			goto err_req;
 		}
 
-		ret = io_req_defer_prep(req);
+		ret = io_req_defer_prep(req, sqe);
 		if (ret) {
 			/* fail even hard links since we don't submit */
 			prev->flags |= REQ_F_FAIL_LINK;
@@ -3632,15 +3647,18 @@ err_req:
 		}
 		trace_io_uring_link(ctx, req, prev);
 		list_add_tail(&req->link_list, &prev->link_list);
-	} else if (req->sqe->flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) {
+	} else if (sqe->flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) {
 		req->flags |= REQ_F_LINK;
-		if (req->sqe->flags & IOSQE_IO_HARDLINK)
+		if (sqe->flags & IOSQE_IO_HARDLINK)
 			req->flags |= REQ_F_HARDLINK;
 
 		INIT_LIST_HEAD(&req->link_list);
+		ret = io_req_defer_prep(req, sqe);
+		if (ret)
+			req->flags |= REQ_F_FAIL_LINK;
 		*link = req;
 	} else {
-		io_queue_sqe(req);
+		io_queue_sqe(req, sqe);
 	}
 
 	return true;
@@ -3685,14 +3703,15 @@ static void io_commit_sqring(struct io_ring_ctx *ctx)
 }
 
 /*
- * Fetch an sqe, if one is available. Note that req->sqe will point to memory
+ * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
  * that is mapped by userspace. This means that care needs to be taken to
  * ensure that reads are stable, as we cannot rely on userspace always
  * being a good citizen. If members of the sqe are validated and then later
  * used, it's important that those reads are done through READ_ONCE() to
  * prevent a re-load down the line.
  */
-static bool io_get_sqring(struct io_ring_ctx *ctx, struct io_kiocb *req)
+static bool io_get_sqring(struct io_ring_ctx *ctx, struct io_kiocb *req,
+			  const struct io_uring_sqe **sqe_ptr)
 {
 	struct io_rings *rings = ctx->rings;
 	u32 *sq_array = ctx->sq_array;
@@ -3719,9 +3738,9 @@ static bool io_get_sqring(struct io_ring_ctx *ctx, struct io_kiocb *req)
 		 * link list.
 		 */
 		req->sequence = ctx->cached_sq_head;
-		req->sqe = &ctx->sq_sqes[head];
-		req->opcode = READ_ONCE(req->sqe->opcode);
-		req->user_data = READ_ONCE(req->sqe->user_data);
+		*sqe_ptr = &ctx->sq_sqes[head];
+		req->opcode = READ_ONCE((*sqe_ptr)->opcode);
+		req->user_data = READ_ONCE((*sqe_ptr)->user_data);
 		ctx->cached_sq_head++;
 		return true;
 	}
@@ -3753,6 +3772,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
 	}
 
 	for (i = 0; i < nr; i++) {
+		const struct io_uring_sqe *sqe;
 		struct io_kiocb *req;
 		unsigned int sqe_flags;
 
@@ -3762,7 +3782,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
 				submitted = -EAGAIN;
 			break;
 		}
-		if (!io_get_sqring(ctx, req)) {
+		if (!io_get_sqring(ctx, req, &sqe)) {
 			__io_free_req(req);
 			break;
 		}
@@ -3776,7 +3796,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
 		}
 
 		submitted++;
-		sqe_flags = req->sqe->flags;
+		sqe_flags = sqe->flags;
 
 		req->ring_file = ring_file;
 		req->ring_fd = ring_fd;
@@ -3784,7 +3804,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
 		req->in_async = async;
 		req->needs_fixed_file = async;
 		trace_io_uring_submit_sqe(ctx, req->user_data, true, async);
-		if (!io_submit_sqe(req, statep, &link))
+		if (!io_submit_sqe(req, sqe, statep, &link))
 			break;
 		/*
 		 * If previous wasn't linked and we have a linked command,
@@ -4702,7 +4722,7 @@ static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
 		if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
 			return -EFAULT;
 
-		dst->iov_base = (void __user *) (unsigned long) ciov.iov_base;
+		dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
 		dst->iov_len = ciov.iov_len;
 		return 0;
 	}