[RFC net-next v3 22/29] io_uring: account locked pages for non-fixed zc

[Pavel Begunkov <asml.silence@xxxxxxxxx>]

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@xxxxxxxxx>
---
 fs/io_uring.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 4a1a1d43e9b3..838030477456 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2825,7 +2825,13 @@ static void __io_notif_complete_tw(struct callback_head *cb)
 {
 	struct io_notif *notif = container_of(cb, struct io_notif, task_work);
 	struct io_ring_ctx *ctx = notif->ctx;
+	struct mmpin *mmp = &notif->uarg.mmp;
 
+	if (unlikely(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;
@@ -6616,6 +6622,7 @@ static 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)
-- 
2.36.1