Line data    Source code

       1             : // SPDX-License-Identifier: GPL-2.0
       2             : #include <linux/kernel.h>
       3             : #include <linux/errno.h>
       4             : #include <linux/file.h>
       5             : #include <linux/io_uring.h>
       6             : #include <linux/security.h>
       7             : #include <linux/nospec.h>
       8             : 
       9             : #include <uapi/linux/io_uring.h>
      10             : 
      11             : #include "io_uring.h"
      12             : #include "rsrc.h"
      13             : #include "uring_cmd.h"
      14             : 
      15           0 : static void io_uring_cmd_work(struct io_kiocb *req, bool *locked)
      16             : {
      17           0 :         struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
      18             : 
      19           0 :         ioucmd->task_work_cb(ioucmd);
      20           0 : }
      21             : 
      22           0 : void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
      23             :                         void (*task_work_cb)(struct io_uring_cmd *))
      24             : {
      25           0 :         struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
      26             : 
      27           0 :         ioucmd->task_work_cb = task_work_cb;
      28           0 :         req->io_task_work.func = io_uring_cmd_work;
      29           0 :         io_req_task_work_add(req);
      30           0 : }
      31             : EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task);
      32             : 
      33             : static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
      34             :                                           u64 extra1, u64 extra2)
      35             : {
      36           0 :         req->extra1 = extra1;
      37           0 :         req->extra2 = extra2;
      38           0 :         req->flags |= REQ_F_CQE32_INIT;
      39             : }
      40             : 
      41             : /*
      42             :  * Called by consumers of io_uring_cmd, if they originally returned
      43             :  * -EIOCBQUEUED upon receiving the command.
      44             :  */
      45           0 : void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2)
      46             : {
      47           0 :         struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
      48             : 
      49           0 :         if (ret < 0)
      50           0 :                 req_set_fail(req);
      51             : 
      52           0 :         io_req_set_res(req, ret, 0);
      53           0 :         if (req->ctx->flags & IORING_SETUP_CQE32)
      54           0 :                 io_req_set_cqe32_extra(req, res2, 0);
      55           0 :         if (req->ctx->flags & IORING_SETUP_IOPOLL)
      56             :                 /* order with io_iopoll_req_issued() checking ->iopoll_complete */
      57           0 :                 smp_store_release(&req->iopoll_completed, 1);
      58             :         else
      59           0 :                 io_req_complete_post(req, 0);
      60           0 : }
      61             : EXPORT_SYMBOL_GPL(io_uring_cmd_done);
      62             : 
      63           0 : int io_uring_cmd_prep_async(struct io_kiocb *req)
      64             : {
      65           0 :         struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
      66             :         size_t cmd_size;
      67             : 
      68             :         BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16);
      69             :         BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80);
      70             : 
      71           0 :         cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128);
      72             : 
      73           0 :         memcpy(req->async_data, ioucmd->cmd, cmd_size);
      74           0 :         return 0;
      75             : }
      76             : 
      77           0 : int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
      78             : {
      79           0 :         struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
      80             : 
      81           0 :         if (sqe->__pad1)
      82             :                 return -EINVAL;
      83             : 
      84           0 :         ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
      85           0 :         if (ioucmd->flags & ~IORING_URING_CMD_FIXED)
      86             :                 return -EINVAL;
      87             : 
      88           0 :         if (ioucmd->flags & IORING_URING_CMD_FIXED) {
      89           0 :                 struct io_ring_ctx *ctx = req->ctx;
      90             :                 u16 index;
      91             : 
      92           0 :                 req->buf_index = READ_ONCE(sqe->buf_index);
      93           0 :                 if (unlikely(req->buf_index >= ctx->nr_user_bufs))
      94             :                         return -EFAULT;
      95           0 :                 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
      96           0 :                 req->imu = ctx->user_bufs[index];
      97           0 :                 io_req_set_rsrc_node(req, ctx, 0);
      98             :         }
      99           0 :         ioucmd->cmd = sqe->cmd;
     100           0 :         ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
     101           0 :         return 0;
     102             : }
     103             : 
     104           0 : int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
     105             : {
     106           0 :         struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
     107           0 :         struct io_ring_ctx *ctx = req->ctx;
     108           0 :         struct file *file = req->file;
     109             :         int ret;
     110             : 
     111           0 :         if (!req->file->f_op->uring_cmd)
     112             :                 return -EOPNOTSUPP;
     113             : 
     114           0 :         ret = security_uring_cmd(ioucmd);
     115             :         if (ret)
     116             :                 return ret;
     117             : 
     118           0 :         if (ctx->flags & IORING_SETUP_SQE128)
     119           0 :                 issue_flags |= IO_URING_F_SQE128;
     120           0 :         if (ctx->flags & IORING_SETUP_CQE32)
     121           0 :                 issue_flags |= IO_URING_F_CQE32;
     122           0 :         if (ctx->flags & IORING_SETUP_IOPOLL) {
     123           0 :                 issue_flags |= IO_URING_F_IOPOLL;
     124           0 :                 req->iopoll_completed = 0;
     125           0 :                 WRITE_ONCE(ioucmd->cookie, NULL);
     126             :         }
     127             : 
     128           0 :         if (req_has_async_data(req))
     129           0 :                 ioucmd->cmd = req->async_data;
     130             : 
     131           0 :         ret = file->f_op->uring_cmd(ioucmd, issue_flags);
     132           0 :         if (ret == -EAGAIN) {
     133           0 :                 if (!req_has_async_data(req)) {
     134           0 :                         if (io_alloc_async_data(req))
     135             :                                 return -ENOMEM;
     136           0 :                         io_uring_cmd_prep_async(req);
     137             :                 }
     138             :                 return -EAGAIN;
     139             :         }
     140             : 
     141           0 :         if (ret != -EIOCBQUEUED) {
     142           0 :                 if (ret < 0)
     143           0 :                         req_set_fail(req);
     144           0 :                 io_req_set_res(req, ret, 0);
     145           0 :                 return ret;
     146             :         }
     147             : 
     148             :         return IOU_ISSUE_SKIP_COMPLETE;
     149             : }
     150             : 
     151           0 : int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
     152             :                               struct iov_iter *iter, void *ioucmd)
     153             : {
     154           0 :         struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
     155             : 
     156           0 :         return io_import_fixed(rw, iter, req->imu, ubuf, len);
     157             : }
     158             : EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);