From 4007c3d8c22a2025367953f4ee36ae106a69d855 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Tue, 29 Oct 2024 09:02:38 -0600
Subject: [PATCH] io_uring/rsrc: add io_reset_rsrc_node() helper

Puts and reset an existing node in a slot, if one exists. Returns true
if a node was there, false if not. This helps cleanup some of the code
that does a lookup just to clear an existing node.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 io_uring/filetable.c | 10 +++-------
 io_uring/rsrc.c      | 12 +++---------
 io_uring/rsrc.h      | 11 +++++++++++
 3 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/io_uring/filetable.c b/io_uring/filetable.c
index 7a9de6718b8a..45f005f5db42 100644
--- a/io_uring/filetable.c
+++ b/io_uring/filetable.c
@@ -58,7 +58,7 @@ static int io_install_fixed_file(struct io_ring_ctx *ctx, struct file *file,
 				 u32 slot_index)
 	__must_hold(&req->ctx->uring_lock)
 {
-	struct io_rsrc_node *node, *old_node;
+	struct io_rsrc_node *node;
 
 	if (io_is_uring_fops(file))
 		return -EBADF;
@@ -71,10 +71,7 @@ static int io_install_fixed_file(struct io_ring_ctx *ctx, struct file *file,
 	if (!node)
 		return -ENOMEM;
 
-	old_node = io_rsrc_node_lookup(&ctx->file_table.data, slot_index);
-	if (old_node)
-		io_put_rsrc_node(old_node);
-	else
+	if (!io_reset_rsrc_node(&ctx->file_table.data, slot_index))
 		io_file_bitmap_set(&ctx->file_table, slot_index);
 
 	ctx->file_table.data.nodes[slot_index] = node;
@@ -133,8 +130,7 @@ int io_fixed_fd_remove(struct io_ring_ctx *ctx, unsigned int offset)
 	node = io_rsrc_node_lookup(&ctx->file_table.data, offset);
 	if (!node)
 		return -EBADF;
-	io_put_rsrc_node(node);
-	ctx->file_table.data.nodes[offset] = NULL;
+	io_reset_rsrc_node(&ctx->file_table.data, offset);
 	io_file_bitmap_clear(&ctx->file_table, offset);
 	return 0;
 }
diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index 0380b2f4ed8d..378f33746457 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -181,7 +181,6 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx,
 		return -EINVAL;
 
 	for (done = 0; done < nr_args; done++) {
-		struct io_rsrc_node *node;
 		u64 tag = 0;
 
 		if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) ||
@@ -197,12 +196,9 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx,
 			continue;
 
 		i = up->offset + done;
-		node = io_rsrc_node_lookup(&ctx->file_table.data, i);
-		if (node) {
-			io_put_rsrc_node(node);
-			ctx->file_table.data.nodes[i] = NULL;
+		if (io_reset_rsrc_node(&ctx->file_table.data, i))
 			io_file_bitmap_clear(&ctx->file_table, i);
-		}
+
 		if (fd != -1) {
 			struct file *file = fget(fd);
 			struct io_rsrc_node *node;
@@ -279,9 +275,7 @@ static int __io_sqe_buffers_update(struct io_ring_ctx *ctx,
 			break;
 		}
 		i = array_index_nospec(up->offset + done, ctx->buf_table.nr);
-		if (ctx->buf_table.nodes[i])
-			io_put_rsrc_node(ctx->buf_table.nodes[i]);
-
+		io_reset_rsrc_node(&ctx->buf_table, i);
 		ctx->buf_table.nodes[i] = node;
 		if (tag)
 			node->tag = tag;
diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h
index 82e08cbba02e..43b19e516f5f 100644
--- a/io_uring/rsrc.h
+++ b/io_uring/rsrc.h
@@ -84,6 +84,17 @@ static inline void io_put_rsrc_node(struct io_rsrc_node *node)
 		io_free_rsrc_node(node);
 }
 
+static inline bool io_reset_rsrc_node(struct io_rsrc_data *data, int index)
+{
+	struct io_rsrc_node *node = data->nodes[index];
+
+	if (!node)
+		return false;
+	io_put_rsrc_node(node);
+	data->nodes[index] = NULL;
+	return true;
+}
+
 static inline void io_req_put_rsrc_nodes(struct io_kiocb *req)
 {
 	if (req->rsrc_nodes[IORING_RSRC_FILE] != rsrc_empty_node) {