diff options
Diffstat (limited to 'io_uring/uring_cmd.c')
| -rw-r--r-- | io_uring/uring_cmd.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c new file mode 100644 index 000000000..92f310dfb --- /dev/null +++ b/io_uring/uring_cmd.c @@ -0,0 +1,162 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/file.h> +#include <linux/io_uring.h> +#include <linux/security.h> +#include <linux/nospec.h> + +#include <uapi/linux/io_uring.h> + +#include "io_uring.h" +#include "rsrc.h" +#include "uring_cmd.h" + +static void io_uring_cmd_work(struct io_kiocb *req, bool *locked) +{ + struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); + unsigned issue_flags = *locked ? 0 : IO_URING_F_UNLOCKED; + + ioucmd->task_work_cb(ioucmd, issue_flags); +} + +void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd, + void (*task_work_cb)(struct io_uring_cmd *, unsigned)) +{ + struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); + + ioucmd->task_work_cb = task_work_cb; + req->io_task_work.func = io_uring_cmd_work; + io_req_task_work_add(req); +} +EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task); + +static inline void io_req_set_cqe32_extra(struct io_kiocb *req, + u64 extra1, u64 extra2) +{ + req->extra1 = extra1; + req->extra2 = extra2; + req->flags |= REQ_F_CQE32_INIT; +} + +/* + * 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 *ioucmd, ssize_t ret, ssize_t res2, + unsigned issue_flags) +{ + struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); + + if (ret < 0) + req_set_fail(req); + + io_req_set_res(req, ret, 0); + if (req->ctx->flags & IORING_SETUP_CQE32) + io_req_set_cqe32_extra(req, res2, 0); + if (req->ctx->flags & IORING_SETUP_IOPOLL) + /* order with io_iopoll_req_issued() checking ->iopoll_complete */ + smp_store_release(&req->iopoll_completed, 1); + else + __io_req_complete(req, issue_flags); +} +EXPORT_SYMBOL_GPL(io_uring_cmd_done); + +int io_uring_cmd_prep_async(struct io_kiocb *req) +{ + struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); + size_t cmd_size; + + BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16); + BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80); + + cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128); + + memcpy(req->async_data, ioucmd->cmd, cmd_size); + return 0; +} + +int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +{ + struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); + + if (sqe->__pad1) + return -EINVAL; + + ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags); + if (ioucmd->flags & ~IORING_URING_CMD_FIXED) + return -EINVAL; + + if (ioucmd->flags & IORING_URING_CMD_FIXED) { + struct io_ring_ctx *ctx = req->ctx; + u16 index; + + req->buf_index = READ_ONCE(sqe->buf_index); + if (unlikely(req->buf_index >= ctx->nr_user_bufs)) + return -EFAULT; + index = array_index_nospec(req->buf_index, ctx->nr_user_bufs); + req->imu = ctx->user_bufs[index]; + io_req_set_rsrc_node(req, ctx, 0); + } + ioucmd->cmd = sqe->cmd; + ioucmd->cmd_op = READ_ONCE(sqe->cmd_op); + return 0; +} + +int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); + struct io_ring_ctx *ctx = req->ctx; + struct file *file = req->file; + int ret; + + if (!file->f_op->uring_cmd) + return -EOPNOTSUPP; + + ret = security_uring_cmd(ioucmd); + if (ret) + return ret; + + if (ctx->flags & IORING_SETUP_SQE128) + issue_flags |= IO_URING_F_SQE128; + if (ctx->flags & IORING_SETUP_CQE32) + issue_flags |= IO_URING_F_CQE32; + if (ctx->flags & IORING_SETUP_IOPOLL) { + if (!file->f_op->uring_cmd_iopoll) + return -EOPNOTSUPP; + issue_flags |= IO_URING_F_IOPOLL; + req->iopoll_completed = 0; + WRITE_ONCE(ioucmd->cookie, NULL); + } + + if (req_has_async_data(req)) + ioucmd->cmd = req->async_data; + + ret = file->f_op->uring_cmd(ioucmd, issue_flags); + if (ret == -EAGAIN) { + if (!req_has_async_data(req)) { + if (io_alloc_async_data(req)) + return -ENOMEM; + io_uring_cmd_prep_async(req); + } + return -EAGAIN; + } + + if (ret != -EIOCBQUEUED) { + if (ret < 0) + req_set_fail(req); + io_req_set_res(req, ret, 0); + return ret; + } + + return IOU_ISSUE_SKIP_COMPLETE; +} + +int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, + struct iov_iter *iter, void *ioucmd) +{ + struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); + + return io_import_fixed(rw, iter, req->imu, ubuf, len); +} +EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed); |