From: Jens Axboe axboe@kernel.dk
mainline inclusion from mainline-5.6-rc1 commit 980ad26304abf11e78caaa68023411b9c088b848 category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA ---------------------------
For the non-vectored variant of READV/WRITEV, we don't need to setup an async io context, and we flag that appropriately in the io_op_defs array. However, in fixing this for the 5.5 kernel in commit 74566df3a71c we didn't have these opcodes, so the check there was added just for the READ_FIXED and WRITE_FIXED opcodes. Replace that check with just a single check for needing async context, that covers all four of these read/write variants that don't use an iovec.
Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: yangerkun yangerkun@huawei.com Reviewed-by: zhangyi (F) yi.zhang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- fs/io_uring.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c index 2fb71b69cff3..58a204cb5337 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2108,8 +2108,7 @@ static int io_setup_async_rw(struct io_kiocb *req, ssize_t io_size, struct iovec *iovec, struct iovec *fast_iov, struct iov_iter *iter) { - if (req->opcode == IORING_OP_READ_FIXED || - req->opcode == IORING_OP_WRITE_FIXED) + if (!io_op_defs[req->opcode].async_ctx) return 0; if (!req->io && io_alloc_async_ctx(req)) return -ENOMEM;