[PATCH 06/17] io_uring: prep for fixed-buffer enabled uring-cmd

Kanchan Joshi
2022-03-08T15:45:30Z

From: Anuj Gupta <anuj20.g@samsung.com>

Refactor the existing code and factor out helper that can be used for
passthrough with fixed-buffer. This is a prep patch.

Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
---
fs/io_uring.c | 19 ++++++++++++++-----
include/linux/io_uring.h | 7 +++++++
2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 1f228a79e68f..ead0cbae8416 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3140,11 +3140,10 @@ static void kiocb_done(struct io_kiocb *req, ssize_t ret,
}
}

-static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
- struct io_mapped_ubuf *imu)
+static int __io_import_fixed(u64 buf_addr, size_t len, int rw,
+ struct iov_iter *iter, struct io_mapped_ubuf *imu)
{
- size_t len = req->rw.len;
- u64 buf_end, buf_addr = req->rw.addr;
+ u64 buf_end;
size_t offset;

if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
@@ -3213,9 +3212,19 @@ static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
imu = READ_ONCE(ctx->user_bufs[index]);
req->imu = imu;
}
- return __io_import_fixed(req, rw, iter, imu);
+ return __io_import_fixed(req->rw.addr, req->rw.len, rw, iter, imu);
}

+int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len,
+ int rw, struct iov_iter *iter, void *ioucmd)
+{
+ struct io_kiocb *req = container_of(ioucmd, struct io_kiocb, uring_cmd);
+ struct io_mapped_ubuf *imu = req->imu;
+
+ return __io_import_fixed(ubuf, len, rw, iter, imu);
+}
+EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);
+
static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
{
if (needs_lock)
diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index cedc68201469..1888a5ea7dbe 100644
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -25,6 +25,8 @@ struct io_uring_cmd {
};

#if defined(CONFIG_IO_URING)
+int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len,
+ int rw, struct iov_iter *iter, void *ioucmd);
void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret);
void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
void (*driver_cb)(struct io_uring_cmd *));
@@ -48,6 +50,11 @@ static inline void io_uring_free(struct task_struct *tsk)
__io_uring_free(tsk);
}
#else
+int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len,
+ int rw, struct iov_iter *iter, void *ioucmd)
+{
+ return -1;
+}
static inline void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret)
{
}
--
2.25.1