[PATCH v2 11/13] io_uring/rsrc: add lockdep sanity checks

Pavel Begunkov
2023-04-04T12:41:08Z

We should hold ->uring_lock while putting nodes with io_put_rsrc_node(),
add a lockdep check for that.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
io_uring/io_uring.c | 4 ++--
io_uring/rsrc.c | 2 +-
io_uring/rsrc.h | 6 ++++--
3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 419d6f42935f..da36fa1eeac9 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1002,7 +1002,7 @@ static void __io_req_complete_post(struct io_kiocb *req, unsigned issue_flags)

if (rsrc_node) {
io_ring_submit_lock(ctx, issue_flags);
- io_put_rsrc_node(rsrc_node);
+ io_put_rsrc_node(ctx, rsrc_node);
io_ring_submit_unlock(ctx, issue_flags);
}
}
@@ -1123,7 +1123,7 @@ static __cold void io_free_req_tw(struct io_kiocb *req, struct io_tw_state *ts)

if (req->rsrc_node) {
io_tw_lock(ctx, ts);
- io_put_rsrc_node(req->rsrc_node);
+ io_put_rsrc_node(ctx, req->rsrc_node);
}
io_dismantle_req(req);
io_put_task_remote(req->task, 1);
diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index cbf563fcb053..95edc5f73204 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -236,7 +236,7 @@ void io_rsrc_node_switch(struct io_ring_ctx *ctx,

atomic_inc(&data_to_kill->refs);
/* put master ref */
- io_put_rsrc_node(rsrc_node);
+ io_put_rsrc_node(ctx, rsrc_node);
ctx->rsrc_node = NULL;
}

diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h
index 3b9f4c57c47c..cf24c3fd701f 100644
--- a/io_uring/rsrc.h
+++ b/io_uring/rsrc.h
@@ -119,8 +119,10 @@ int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
unsigned int size, unsigned int type);

-static inline void io_put_rsrc_node(struct io_rsrc_node *node)
+static inline void io_put_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)
{
+ lockdep_assert_held(&ctx->uring_lock);
+
if (node && !--node->refs)
io_rsrc_node_ref_zero(node);
}
@@ -128,7 +130,7 @@ static inline void io_put_rsrc_node(struct io_rsrc_node *node)
static inline void io_req_put_rsrc_locked(struct io_kiocb *req,
struct io_ring_ctx *ctx)
{
- io_put_rsrc_node(req->rsrc_node);
+ io_put_rsrc_node(ctx, req->rsrc_node);
}

static inline void io_charge_rsrc_node(struct io_ring_ctx *ctx,
--
2.39.1