io_uring: indicate if io_kbuf_recycle did recycle anything

It can be useful to know if io_kbuf_recycle did actually recycle the
buffer on the request, or if it left the request alone.

Signed-off-by: Dylan Yudaken <dyudaken@gmail.com>
Link: https://lore.kernel.org/r/20231106203909.197089-2-dyudaken@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index fea0681..a1e4239 100644 (file)
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -52,7 +52,7 @@ static int io_buffer_add_list(struct io_ring_ctx *ctx,
        return xa_err(xa_store(&ctx->io_bl_xa, bgid, bl, GFP_KERNEL));
 }
 
-void io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
+bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
 {
        struct io_ring_ctx *ctx = req->ctx;
        struct io_buffer_list *bl;
@@ -65,7 +65,7 @@ void io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
         * multiple use.
         */
        if (req->flags & REQ_F_PARTIAL_IO)
-               return;
+               return false;
 
        io_ring_submit_lock(ctx, issue_flags);
 
@@ -76,7 +76,7 @@ void io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
        req->buf_index = buf->bgid;
 
        io_ring_submit_unlock(ctx, issue_flags);
-       return;
+       return true;
 }
 
 unsigned int __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags)

diff --git a/io_uring/kbuf.h b/io_uring/kbuf.h
index d14345e..f2d6152 100644 (file)
--- a/io_uring/kbuf.h
+++ b/io_uring/kbuf.h
@@ -53,11 +53,11 @@ int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg);
 
 unsigned int __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags);
 
-void io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags);
+bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags);
 
 void *io_pbuf_get_address(struct io_ring_ctx *ctx, unsigned long bgid);
 
-static inline void io_kbuf_recycle_ring(struct io_kiocb *req)
+static inline bool io_kbuf_recycle_ring(struct io_kiocb *req)
 {
        /*
         * We don't need to recycle for REQ_F_BUFFER_RING, we can just clear
@@ -80,8 +80,10 @@ static inline void io_kbuf_recycle_ring(struct io_kiocb *req)
                } else {
                        req->buf_index = req->buf_list->bgid;
                        req->flags &= ~REQ_F_BUFFER_RING;
+                       return true;
                }
        }
+       return false;
 }
 
 static inline bool io_do_buffer_select(struct io_kiocb *req)
@@ -91,12 +93,13 @@ static inline bool io_do_buffer_select(struct io_kiocb *req)
        return !(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING));
 }
 
-static inline void io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags)
+static inline bool io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags)
 {
        if (req->flags & REQ_F_BUFFER_SELECTED)
-               io_kbuf_recycle_legacy(req, issue_flags);
+               return io_kbuf_recycle_legacy(req, issue_flags);
        if (req->flags & REQ_F_BUFFER_RING)
-               io_kbuf_recycle_ring(req);
+               return io_kbuf_recycle_ring(req);
+       return false;
 }
 
 static inline unsigned int __io_put_kbuf_list(struct io_kiocb *req,