io_uring/nop: reuse req->buf_index

There is already a field in io_kiocb that can store a registered buffer
index, use that instead of stashing the value into struct io_nop.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250224213116.3509093-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/nop.c b/io_uring/nop.c
index 5e5196df650a19e032e53594db6f1d1bea71c5f2..ea539531cb5f6e72677b4a4af04babedbf580ff0 100644 (file)
--- a/io_uring/nop.c
+++ b/io_uring/nop.c
@@ -16,7 +16,6 @@ struct io_nop {
        struct file     *file;
        int             result;
        int             fd;
-       int             buffer;
        unsigned int    flags;
 };
 
@@ -40,9 +39,7 @@ int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
        else
                nop->fd = -1;
        if (nop->flags & IORING_NOP_FIXED_BUFFER)
-               nop->buffer = READ_ONCE(sqe->buf_index);
-       else
-               nop->buffer = -1;
+               req->buf_index = READ_ONCE(sqe->buf_index);
        return 0;
 }
 
@@ -69,7 +66,7 @@ int io_nop(struct io_kiocb *req, unsigned int issue_flags)
 
                ret = -EFAULT;
                io_ring_submit_lock(ctx, issue_flags);
-               node = io_rsrc_node_lookup(&ctx->buf_table, nop->buffer);
+               node = io_rsrc_node_lookup(&ctx->buf_table, req->buf_index);
                if (node) {
                        io_req_assign_buf_node(req, node);
                        ret = 0;