io_uring: get rid of delayed mm check

Fail fast if can't grab mm, so past that requests always have an mm
when required. This allows us to remove req->user altogether.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2020-02-06 21:16:09 +03:00 committed by Jens Axboe
parent 4c46bef2e9
commit 1cb1edb2f5

View File

@ -553,7 +553,6 @@ struct io_kiocb {
* llist_node is only used for poll deferred completions
*/
struct llist_node llist_node;
bool has_user;
bool in_async;
bool needs_fixed_file;
u8 opcode;
@ -2056,9 +2055,6 @@ static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
return iorw->size;
}
if (!req->has_user)
return -EFAULT;
#ifdef CONFIG_COMPAT
if (req->ctx->compat)
return compat_import_iovec(rw, buf, sqe_len, UIO_FASTIOV,
@ -4446,7 +4442,6 @@ static void io_wq_submit_work(struct io_wq_work **workptr)
}
if (!ret) {
req->has_user = (work->flags & IO_WQ_WORK_HAS_MM) != 0;
req->in_async = true;
do {
ret = io_issue_sqe(req, NULL, &nxt, false);
@ -4950,6 +4945,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
for (i = 0; i < nr; i++) {
const struct io_uring_sqe *sqe;
struct io_kiocb *req;
int err;
req = io_get_req(ctx, statep);
if (unlikely(!req)) {
@ -4966,20 +4962,23 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
submitted++;
if (unlikely(req->opcode >= IORING_OP_LAST)) {
io_cqring_add_event(req, -EINVAL);
err = -EINVAL;
fail_req:
io_cqring_add_event(req, err);
io_double_put_req(req);
break;
}
if (io_op_defs[req->opcode].needs_mm && !*mm) {
mm_fault = mm_fault || !mmget_not_zero(ctx->sqo_mm);
if (!mm_fault) {
use_mm(ctx->sqo_mm);
*mm = ctx->sqo_mm;
if (unlikely(mm_fault)) {
err = -EFAULT;
goto fail_req;
}
use_mm(ctx->sqo_mm);
*mm = ctx->sqo_mm;
}
req->has_user = *mm != NULL;
req->in_async = async;
req->needs_fixed_file = async;
trace_io_uring_submit_sqe(ctx, req->opcode, req->user_data,