[PATCH net-next v4 20/27] io_uring: account locked pages for non-fixed zc

Pavel Begunkov
2022-07-07T11:53:19Z

Fixed buffers are RLIMIT_MEMLOCK accounted, however it doesn't cover iovec
based zerocopy sends. Do the accounting on the io_uring side.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
io_uring/net.c | 1 +
io_uring/notif.c | 6 ++++++
2 files changed, 7 insertions(+)

diff --git a/io_uring/net.c b/io_uring/net.c
index 399267e8f1ef..69273d4f4ef0 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -724,6 +724,7 @@ int io_sendzc(struct io_kiocb *req, unsigned int issue_flags)
ret = import_single_range(WRITE, zc->buf, zc->len, &iov, &msg.msg_iter);
if (unlikely(ret))
return ret;
+ mm_account_pinned_pages(&notif->uarg.mmp, zc->len);

msg_flags = zc->msg_flags | MSG_ZEROCOPY;
if (issue_flags & IO_URING_F_NONBLOCK)
diff --git a/io_uring/notif.c b/io_uring/notif.c
index e6d98dc208c7..c5179e5c1cd6 100644
--- a/io_uring/notif.c
+++ b/io_uring/notif.c
@@ -14,7 +14,13 @@ static void __io_notif_complete_tw(struct callback_head *cb)
struct io_notif *notif = container_of(cb, struct io_notif, task_work);
struct io_rsrc_node *rsrc_node = notif->rsrc_node;
struct io_ring_ctx *ctx = notif->ctx;
+ struct mmpin *mmp = &notif->uarg.mmp;

+ if (mmp->user) {
+ atomic_long_sub(mmp->num_pg, &mmp->user->locked_vm);
+ free_uid(mmp->user);
+ mmp->user = NULL;
+ }
if (likely(notif->task)) {
io_put_task(notif->task, 1);
notif->task = NULL;
--
2.36.1