io_uring: read 'count' for IORING_OP_TIMEOUT in prep handler

Add the count field to struct io_timeout, and ensure the prep handler
has read it. Timeout also needs an async context always, set it up
in the prep handler if we don't have one.

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

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 89e5b19..7e8d287 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -330,6 +330,7 @@ struct io_timeout {
        struct file                     *file;
        u64                             addr;
        int                             flags;
+       unsigned                        count;
 };
 
 struct io_rw {
@@ -2902,7 +2903,12 @@ 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 (!io && io_alloc_async_ctx(req))
+               return -ENOMEM;
+
+       data = &req->io->timeout;
        data->req = req;
        req->flags |= REQ_F_TIMEOUT;
 
@@ -2920,7 +2926,6 @@ 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;
@@ -2942,7 +2947,7 @@ 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);