From: Pavel Begunkov <asml.silence@xxxxxxxxx>
io_uring needs private bits in cmd's ->async_data, and they should never
be exposed to drivers as it'd certainly be abused. Leave struct
io_uring_cmd_data for the drivers but wrap it into a structure. It's a
prep patch and doesn't do anything useful yet.
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
io_uring/io_uring.c | 2 +-
io_uring/opdef.c | 2 +-
io_uring/uring_cmd.c | 18 +++++++++++-------
io_uring/uring_cmd.h | 6 ++++++
4 files changed, 19 insertions(+), 9 deletions(-)
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 7f26ad334e30..5eb9be063a7c 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -335,7 +335,7 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
sizeof(struct io_async_rw),
offsetof(struct io_async_rw, clear));
ret |= io_alloc_cache_init(&ctx->cmd_cache, IO_ALLOC_CACHE_MAX,
- sizeof(struct io_uring_cmd_data), 0);
+ sizeof(struct io_async_cmd), 0);
spin_lock_init(&ctx->msg_lock);
ret |= io_alloc_cache_init(&ctx->msg_cache, IO_ALLOC_CACHE_MAX,
sizeof(struct io_kiocb), 0);
diff --git a/io_uring/opdef.c b/io_uring/opdef.c
index 7fd173197b1e..e4aa61a414fb 100644
--- a/io_uring/opdef.c
+++ b/io_uring/opdef.c
@@ -416,7 +416,7 @@ const struct io_issue_def io_issue_defs[] = {
.plug = 1,
.iopoll = 1,
.iopoll_queue = 1,
- .async_size = sizeof(struct io_uring_cmd_data),
+ .async_size = sizeof(struct io_async_cmd),
.prep = io_uring_cmd_prep,
.issue = io_uring_cmd,
},
diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
index 792bd54851b1..7c126ee497ea 100644
--- a/io_uring/uring_cmd.c
+++ b/io_uring/uring_cmd.c
@@ -19,7 +19,8 @@
static void io_req_uring_cleanup(struct io_kiocb *req, unsigned int issue_flags)
{
struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
- struct io_uring_cmd_data *cache = req->async_data;
+ struct io_async_cmd *ac = req->async_data;
+ struct io_uring_cmd_data *cache = &ac->data;
if (cache->op_data) {
kfree(cache->op_data);
@@ -169,12 +170,15 @@ static int io_uring_cmd_prep_setup(struct io_kiocb *req,
const struct io_uring_sqe *sqe)
{
struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
- struct io_uring_cmd_data *cache;
+ struct io_async_cmd *ac;
- cache = io_uring_alloc_async_data(&req->ctx->cmd_cache, req);
- if (!cache)
+ /* see io_uring_cmd_get_async_data() */
+ BUILD_BUG_ON(offsetof(struct io_async_cmd, data) != 0);
+
+ ac = io_uring_alloc_async_data(&req->ctx->cmd_cache, req);
+ if (!ac)
return -ENOMEM;
- cache->op_data = NULL;
+ ac->data.op_data = NULL;
/*
* Unconditionally cache the SQE for now - this is only needed for
@@ -183,8 +187,8 @@ static int io_uring_cmd_prep_setup(struct io_kiocb *req,
* that it doesn't read in per-op data, play it safe and ensure that
* any SQE data is stable beyond prep. This can later get relaxed.
*/
- memcpy(cache->sqes, sqe, uring_sqe_size(req->ctx));
- ioucmd->sqe = cache->sqes;
+ memcpy(ac->data.sqes, sqe, uring_sqe_size(req->ctx));
+ ioucmd->sqe = ac->data.sqes;
return 0;
}
diff --git a/io_uring/uring_cmd.h b/io_uring/uring_cmd.h
index f6837ee0955b..2ec3a8785534 100644
--- a/io_uring/uring_cmd.h
+++ b/io_uring/uring_cmd.h
@@ -1,5 +1,11 @@
// SPDX-License-Identifier: GPL-2.0
+#include <linux/io_uring/cmd.h>
+
+struct io_async_cmd {
+ struct io_uring_cmd_data data;
+};
+
int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags);
int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
--
2.43.0
