io_uring: modularize io_sqe_buffers_register
Move allocation of buffer management structures, and validation of
buffers into separate routines.
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index ec70ba0..4cdf0f9 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8579,13 +8579,8 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
return ret;
}
-static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
- unsigned int nr_args)
+static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
{
- int i, ret;
- struct iovec iov;
- struct page *last_hpage = NULL;
-
if (ctx->user_bufs)
return -EBUSY;
if (!nr_args || nr_args > UIO_MAXIOV)
@@ -8596,6 +8591,37 @@ static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
if (!ctx->user_bufs)
return -ENOMEM;
+ return 0;
+}
+
+static int io_buffer_validate(struct iovec *iov)
+{
+ /*
+ * Don't impose further limits on the size and buffer
+ * constraints here, we'll -EINVAL later when IO is
+ * submitted if they are wrong.
+ */
+ if (!iov->iov_base || !iov->iov_len)
+ return -EFAULT;
+
+ /* arbitrary limit, but we need something */
+ if (iov->iov_len > SZ_1G)
+ return -EFAULT;
+
+ return 0;
+}
+
+static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
+ unsigned int nr_args)
+{
+ int i, ret;
+ struct iovec iov;
+ struct page *last_hpage = NULL;
+
+ ret = io_buffers_map_alloc(ctx, nr_args);
+ if (ret)
+ return ret;
+
for (i = 0; i < nr_args; i++) {
struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
@@ -8603,17 +8629,8 @@ static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
if (ret)
break;
- /*
- * Don't impose further limits on the size and buffer
- * constraints here, we'll -EINVAL later when IO is
- * submitted if they are wrong.
- */
- ret = -EFAULT;
- if (!iov.iov_base || !iov.iov_len)
- break;
-
- /* arbitrary limit, but we need something */
- if (iov.iov_len > SZ_1G)
+ ret = io_buffer_validate(&iov);
+ if (ret)
break;
ret = io_sqe_buffer_register(ctx, &iov, imu, &last_hpage);
