Extract a helper io_uring_quiesce_ctx(), which takes care of ctx
quiesce, it's complex enough.
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
fs/io_uring.c | 52 ++++++++++++++++++++++++++++-----------------------
1 file changed, 29 insertions(+), 23 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 3f764f2f2982..6e781c064e74 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -9683,6 +9683,33 @@ static bool io_register_op_must_quiesce(int op)
}
}
+static int io_uring_quiesce_ctx(struct io_ring_ctx *ctx)
+{
+ int ret;
+
+ percpu_ref_kill(&ctx->refs);
+ /*
+ * Drop uring mutex before waiting for references to exit. If
+ * another thread is currently inside io_uring_enter() it might
+ * need to grab the uring_lock to make progress. If we hold it
+ * here across the drain wait, then we can deadlock. It's safe
+ * to drop the mutex here, since no new references will come in
+ * after we've killed the percpu ref.
+ */
+ mutex_unlock(&ctx->uring_lock);
+ do {
+ ret = wait_for_completion_interruptible(&ctx->ref_comp);
+ if (!ret)
+ break;
+ ret = io_run_task_work_sig();
+ } while (ret >= 0);
+ mutex_lock(&ctx->uring_lock);
+
+ if (ret && io_refs_resurrect(&ctx->refs, &ctx->ref_comp))
+ return ret;
+ return 0;
+}
+
static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
void __user *arg, unsigned nr_args)
__releases(ctx->uring_lock)
@@ -9699,29 +9726,8 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
return -ENXIO;
if (io_register_op_must_quiesce(opcode)) {
- percpu_ref_kill(&ctx->refs);
-
- /*
- * Drop uring mutex before waiting for references to exit. If
- * another thread is currently inside io_uring_enter() it might
- * need to grab the uring_lock to make progress. If we hold it
- * here across the drain wait, then we can deadlock. It's safe
- * to drop the mutex here, since no new references will come in
- * after we've killed the percpu ref.
- */
- mutex_unlock(&ctx->uring_lock);
- do {
- ret = wait_for_completion_interruptible(&ctx->ref_comp);
- if (!ret)
- break;
- ret = io_run_task_work_sig();
- if (ret < 0)
- break;
- } while (1);
-
- mutex_lock(&ctx->uring_lock);
-
- if (ret && io_refs_resurrect(&ctx->refs, &ctx->ref_comp))
+ ret = io_uring_quiesce_ctx(ctx);
+ if (ret)
return ret;
}
--
2.24.0
