This is a file private kind of request. io_uring doesn't know what's
in this command type, it's for the file_operations->uring_cmd()
handler to deal with.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
fs/io_uring.c | 54 ++++++++++++++++++++++++++++++++++++++++
include/linux/io_uring.h | 16 ++++++++++++
2 files changed, 70 insertions(+)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index fecf10e0625f..a66f953f71d4 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -770,6 +770,7 @@ struct io_kiocb {
struct io_shutdown shutdown;
struct io_rename rename;
struct io_unlink unlink;
+ struct io_uring_cmd uring_cmd;
/* use only after cleaning per-op data, see io_clean_op() */
struct io_completion compl;
};
@@ -1002,6 +1003,7 @@ static const struct io_op_def io_op_defs[] = {
[IORING_OP_RENAMEAT] = {},
[IORING_OP_UNLINKAT] = {},
[IORING_OP_URING_CMD] = {
+ .needs_file = 1,
.offsets = 1,
},
};
@@ -3565,6 +3567,53 @@ static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
return 0;
}
+/*
+ * Called by consumers of io_uring_cmd, if they originally returned
+ * -EIOCBQUEUED upon receiving the command.
+ */
+void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret)
+{
+ struct io_kiocb *req = container_of(cmd, struct io_kiocb, uring_cmd);
+
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+}
+EXPORT_SYMBOL(io_uring_cmd_done);
+
+static int io_uring_cmd_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ const struct io_uring_cmd_sqe *csqe = (const void *) sqe;
+ struct io_uring_cmd *cmd = &req->uring_cmd;
+
+ if (!req->file->f_op->uring_cmd)
+ return -EOPNOTSUPP;
+
+ cmd->op = READ_ONCE(csqe->op);
+ cmd->len = READ_ONCE(csqe->len);
+
+ /*
+ * The payload is the last 40 bytes of an io_uring_cmd_sqe, with the
+ * type being defined by the recipient.
+ */
+ memcpy(&cmd->pdu, &csqe->pdu, sizeof(cmd->pdu));
+ return 0;
+}
+
+static int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
+{
+ struct file *file = req->file;
+ int ret;
+
+ ret = file->f_op->uring_cmd(&req->uring_cmd, issue_flags);
+ /* queued async, consumer will call io_uring_cmd_done() when complete */
+ if (ret == -EIOCBQUEUED)
+ return 0;
+ io_uring_cmd_done(&req->uring_cmd, ret);
+ return 0;
+}
+
static int io_shutdown_prep(struct io_kiocb *req,
const struct io_uring_sqe *sqe)
{
@@ -5858,6 +5907,8 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
return io_renameat_prep(req, sqe);
case IORING_OP_UNLINKAT:
return io_unlinkat_prep(req, sqe);
+ case IORING_OP_URING_CMD:
+ return io_uring_cmd_prep(req, sqe);
}
printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
@@ -6114,6 +6165,9 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
case IORING_OP_UNLINKAT:
ret = io_unlinkat(req, issue_flags);
break;
+ case IORING_OP_URING_CMD:
+ ret = io_uring_cmd(req, issue_flags);
+ break;
default:
ret = -EINVAL;
break;
diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index 9761a0ec9f95..fd5c8ca40a70 100644
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -30,7 +30,20 @@ struct io_uring_task {
struct callback_head task_work;
};
+/*
+ * Note that the first member here must be a struct file, as the
+ * io_uring command layout depends on that.
+ */
+struct io_uring_cmd {
+ struct file *file;
+ __u16 op;
+ __u16 unused;
+ __u32 len;
+ __u64 pdu[5]; /* 40 bytes available inline for free use */
+};
+
#if defined(CONFIG_IO_URING)
+void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret);
struct sock *io_uring_get_socket(struct file *file);
void __io_uring_task_cancel(void);
void __io_uring_files_cancel(struct files_struct *files);
@@ -52,6 +65,9 @@ static inline void io_uring_free(struct task_struct *tsk)
__io_uring_free(tsk);
}
#else
+static inline void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret)
+{
+}
static inline struct sock *io_uring_get_socket(struct file *file)
{
return NULL;
--
2.31.0
