linux/io_uring/nop.c
Ming Lei 039c878db7 io_uring/rsrc: add & apply io_req_assign_buf_node()
The following pattern becomes more and more:

+       io_req_assign_rsrc_node(&req->buf_node, node);
+       req->flags |= REQ_F_BUF_NODE;

so make it a helper, which is less fragile to use than above code, for
example, the BUF_NODE flag is even missed in current io_uring_cmd_prep().

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241107110149.890530-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-07 15:24:33 -07:00

81 lines
1.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/io_uring.h>
#include <uapi/linux/io_uring.h>
#include "io_uring.h"
#include "rsrc.h"
#include "nop.h"
struct io_nop {
/* NOTE: kiocb has the file as the first member, so don't do it here */
struct file *file;
int result;
int fd;
int buffer;
unsigned int flags;
};
#define NOP_FLAGS (IORING_NOP_INJECT_RESULT | IORING_NOP_FIXED_FILE | \
IORING_NOP_FIXED_BUFFER | IORING_NOP_FILE)
int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_nop *nop = io_kiocb_to_cmd(req, struct io_nop);
nop->flags = READ_ONCE(sqe->nop_flags);
if (nop->flags & ~NOP_FLAGS)
return -EINVAL;
if (nop->flags & IORING_NOP_INJECT_RESULT)
nop->result = READ_ONCE(sqe->len);
else
nop->result = 0;
if (nop->flags & IORING_NOP_FIXED_FILE)
nop->fd = READ_ONCE(sqe->fd);
if (nop->flags & IORING_NOP_FIXED_BUFFER)
nop->buffer = READ_ONCE(sqe->buf_index);
return 0;
}
int io_nop(struct io_kiocb *req, unsigned int issue_flags)
{
struct io_nop *nop = io_kiocb_to_cmd(req, struct io_nop);
int ret = nop->result;
if (nop->flags & IORING_NOP_FILE) {
if (nop->flags & IORING_NOP_FIXED_FILE) {
req->file = io_file_get_fixed(req, nop->fd, issue_flags);
req->flags |= REQ_F_FIXED_FILE;
} else {
req->file = io_file_get_normal(req, nop->fd);
}
if (!req->file) {
ret = -EBADF;
goto done;
}
}
if (nop->flags & IORING_NOP_FIXED_BUFFER) {
struct io_ring_ctx *ctx = req->ctx;
struct io_rsrc_node *node;
ret = -EFAULT;
io_ring_submit_lock(ctx, issue_flags);
node = io_rsrc_node_lookup(&ctx->buf_table, nop->buffer);
if (node) {
io_req_assign_buf_node(req, node);
ret = 0;
}
io_ring_submit_unlock(ctx, issue_flags);
}
done:
if (ret < 0)
req_set_fail(req);
io_req_set_res(req, nop->result, 0);
return IOU_OK;
}