io_uring: split ref_node alloc and init

A simple prep patch allowing to set refnode callbacks after it was
allocated. This needed to 1) keep ourself off of hi-level functions
where it's not pretty and they are not necessary 2) amortise ref_node
allocation in the future, e.g. for updates.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index ab5bf1bf077921ab3c9357ca9f5f8881772552f7..bb51f2abd009e7dfd7a6cd23ce82c968f017aeef 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1009,8 +1009,10 @@ static void __io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
                                            struct task_struct *task);
 
 static void destroy_fixed_rsrc_ref_node(struct fixed_rsrc_ref_node *ref_node);
-static struct fixed_rsrc_ref_node *alloc_fixed_file_ref_node(
+static struct fixed_rsrc_ref_node *alloc_fixed_rsrc_ref_node(
                        struct io_ring_ctx *ctx);
+static void init_fixed_file_ref_node(struct io_ring_ctx *ctx,
+                                    struct fixed_rsrc_ref_node *ref_node);
 
 static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
                             struct io_comp_state *cs);
@@ -7380,9 +7382,10 @@ static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
 
        if (!data)
                return -ENXIO;
-       backup_node = alloc_fixed_file_ref_node(ctx);
+       backup_node = alloc_fixed_rsrc_ref_node(ctx);
        if (!backup_node)
                return -ENOMEM;
+       init_fixed_file_ref_node(ctx, backup_node);
 
        io_rsrc_ref_lock(ctx);
        ref_node = data->node;
@@ -7819,18 +7822,11 @@ static struct fixed_rsrc_ref_node *alloc_fixed_rsrc_ref_node(
        return ref_node;
 }
 
-static struct fixed_rsrc_ref_node *alloc_fixed_file_ref_node(
-                       struct io_ring_ctx *ctx)
+static void init_fixed_file_ref_node(struct io_ring_ctx *ctx,
+                                    struct fixed_rsrc_ref_node *ref_node)
 {
-       struct fixed_rsrc_ref_node *ref_node;
-
-       ref_node = alloc_fixed_rsrc_ref_node(ctx);
-       if (!ref_node)
-               return NULL;
-
        ref_node->rsrc_data = ctx->file_data;
        ref_node->rsrc_put = io_ring_file_put;
-       return ref_node;
 }
 
 static void destroy_fixed_rsrc_ref_node(struct fixed_rsrc_ref_node *ref_node)
@@ -7915,11 +7911,12 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
                return ret;
        }
 
-       ref_node = alloc_fixed_file_ref_node(ctx);
+       ref_node = alloc_fixed_rsrc_ref_node(ctx);
        if (!ref_node) {
                io_sqe_files_unregister(ctx);
                return -ENOMEM;
        }
+       init_fixed_file_ref_node(ctx, ref_node);
 
        io_sqe_rsrc_set_node(ctx, file_data, ref_node);
        return ret;
@@ -8022,9 +8019,10 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx,
        if (done > ctx->nr_user_files)
                return -EINVAL;
 
-       ref_node = alloc_fixed_file_ref_node(ctx);
+       ref_node = alloc_fixed_rsrc_ref_node(ctx);
        if (!ref_node)
                return -ENOMEM;
+       init_fixed_file_ref_node(ctx, ref_node);
 
        done = 0;
        fds = u64_to_user_ptr(up->data);