[RFC] Bluetooth: hci_sock: Add support for BT_{SND,RCV}BUF
From: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date: 2021-09-14 22:34:56
Subsystem:
bluetooth subsystem, the rest · Maintainers:
Marcel Holtmann, Luiz Augusto von Dentz, Linus Torvalds
From: Luiz Augusto von Dentz <redacted>
This adds support for BT_{SND,RCV}BUF so userspace can set MTU based on
the channel usage.
Fixes: https://github.com/bluez/bluez/issues/201
Signed-off-by: Luiz Augusto von Dentz <redacted>
---
net/bluetooth/hci_sock.c | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index 31a2eefede3c..8cebf8a0e85d 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c@@ -57,6 +57,7 @@ struct hci_pinfo { unsigned long flags; __u32 cookie; char comm[TASK_COMM_LEN]; + unsigned int mtu; }; static struct hci_dev *hci_hdev_from_sock(struct sock *sk)
@@ -1374,6 +1375,10 @@ static int hci_sock_bind(struct socket *sock, struct sockaddr *addr, break; } + /* Default MTU to HCI_MAX_FRAME_SIZE if not set */ + if (!hci_pi(sk)->mtu) + hci_pi(sk)->mtu = HCI_MAX_FRAME_SIZE; + sk->sk_state = BT_BOUND; done:
@@ -1704,7 +1709,7 @@ static int hci_sock_sendmsg(struct socket *sock, struct msghdr *msg, if (flags & ~(MSG_DONTWAIT | MSG_NOSIGNAL | MSG_ERRQUEUE | MSG_CMSG_COMPAT)) return -EINVAL; - if (len < 4 || len > HCI_MAX_FRAME_SIZE) + if (len < 4 || len > hci_pi(sk)->mtu) return -EINVAL; skb = bt_skb_sendmsg(sk, msg, len, len, 0, 0);
@@ -1899,6 +1904,16 @@ static int hci_sock_setsockopt(struct socket *sock, int level, int optname, } break; + case BT_SNDMTU: + case BT_RCVMTU: + if (copy_from_sockptr(&opt, optval, sizeof(u16))) { + err = -EFAULT; + break; + } + + hci_pi(sk)->mtu = opt; + break; + default: err = -ENOPROTOOPT; break;
@@ -1968,6 +1983,12 @@ static int hci_sock_getsockopt(struct socket *sock, int level, int optname, err = -EFAULT; break; + case BT_SNDMTU: + case BT_RCVMTU: + if (put_user(hci_pi(sk)->mtu, (u32 __user *)optval)) + err = -EFAULT; + break; + default: err = -ENOPROTOOPT; break;
--
2.31.1