treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

85 files changed, 175 insertions, 176 deletions

diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index 3dd7c972677b..ec8408d1638f 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -367,7 +367,7 @@ static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 	case SIOCSHWTSTAMP:
 		if (!net_eq(dev_net(dev), &init_net))
 			break;
-		/* fall through */
+		fallthrough;
 	case SIOCGMIIPHY:
 	case SIOCGMIIREG:
 	case SIOCSMIIREG:
diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c
index 3debad93be1a..bc8807d9281f 100644
--- a/net/9p/trans_xen.c
+++ b/net/9p/trans_xen.c
@@ -520,7 +520,7 @@ static void xen_9pfs_front_changed(struct xenbus_device *dev,
 	case XenbusStateClosed:
 		if (dev->state == XenbusStateClosed)
 			break;
-		/* fall through - Missed the backend's CLOSING state */
+		fallthrough;	/* Missed the backend's CLOSING state */
 	case XenbusStateClosing:
 		xenbus_frontend_closed(dev);
 		break;
diff --git a/net/atm/common.c b/net/atm/common.c
index 84367b844b14..1cfa9bf1d187 100644
--- a/net/atm/common.c
+++ b/net/atm/common.c
@@ -297,7 +297,7 @@ static int adjust_tp(struct atm_trafprm *tp, unsigned char aal)
 		break;
 	default:
 		pr_warn("AAL problems ... (%d)\n", aal);
-		/* fall through */
+		fallthrough;
 	case ATM_AAL5:
 		max_sdu = ATM_MAX_AAL5_PDU;
 	}
@@ -417,7 +417,7 @@ static int __vcc_connect(struct atm_vcc *vcc, struct atm_dev *dev, short vpi,
 	case ATM_NO_AAL:
 		/* ATM_AAL5 is also used in the "0 for default" case */
 		vcc->qos.aal = ATM_AAL5;
-		/* fall through */
+		fallthrough;
 	case ATM_AAL5:
 		error = atm_init_aal5(vcc);
 		vcc->stats = &dev->stats.aal5;
diff --git a/net/atm/lec.c b/net/atm/lec.c
index 875fc0bc1780..b570ef919c28 100644
--- a/net/atm/lec.c
+++ b/net/atm/lec.c
@@ -380,7 +380,7 @@ static int lec_atm_send(struct atm_vcc *vcc, struct sk_buff *skb)
 
 		if (mesg->content.normal.no_source_le_narp)
 			break;
-		/* FALL THROUGH */
+		fallthrough;
 	case l_arp_update:
 		lec_arp_update(priv, mesg->content.normal.mac_addr,
 			       mesg->content.normal.atm_addr,
diff --git a/net/atm/resources.c b/net/atm/resources.c
index 94bdc6527ee8..53236986dfe0 100644
--- a/net/atm/resources.c
+++ b/net/atm/resources.c
@@ -266,7 +266,7 @@ int atm_dev_ioctl(unsigned int cmd, void __user *buf, int __user *sioc_len,
 				goto done;
 			}
 	}
-	/* fall through */
+		fallthrough;
 	case ATM_SETESIF:
 	{
 		unsigned char esi[ESI_LEN];
@@ -288,7 +288,7 @@ int atm_dev_ioctl(unsigned int cmd, void __user *buf, int __user *sioc_len,
 			error = -EPERM;
 			goto done;
 		}
-		/* fall through */
+		fallthrough;
 	case ATM_GETSTAT:
 		size = sizeof(struct atm_dev_stats);
 		error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
@@ -361,7 +361,7 @@ int atm_dev_ioctl(unsigned int cmd, void __user *buf, int __user *sioc_len,
 			error = -EINVAL;
 			goto done;
 		}
-		/* fall through */
+		fallthrough;
 	case ATM_SETCIRANGE:
 	case SONET_GETSTATZ:
 	case SONET_SETDIAG:
@@ -371,7 +371,7 @@ int atm_dev_ioctl(unsigned int cmd, void __user *buf, int __user *sioc_len,
 			error = -EPERM;
 			goto done;
 		}
-		/* fall through */
+		fallthrough;
 	default:
 		if (IS_ENABLED(CONFIG_COMPAT) && compat) {
 #ifdef CONFIG_COMPAT
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 99eb8c6c0fbc..a66f211726e7 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -425,7 +425,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
 	case BPF_PROG_TYPE_SCHED_CLS:
 	case BPF_PROG_TYPE_SCHED_ACT:
 		is_l2 = true;
-		/* fall through */
+		fallthrough;
 	case BPF_PROG_TYPE_LWT_IN:
 	case BPF_PROG_TYPE_LWT_OUT:
 	case BPF_PROG_TYPE_LWT_XMIT:
diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c
index b93876c57fc4..1be4c898b2fa 100644
--- a/net/can/j1939/socket.c
+++ b/net/can/j1939/socket.c
@@ -1086,7 +1086,7 @@ static int j1939_sk_send_loop(struct j1939_priv *priv,  struct sock *sk,
 		break;
 	case -ERESTARTSYS:
 		ret = -EINTR;
-		/* fall through */
+		fallthrough;
 	case -EAGAIN: /* OK */
 		if (todo_size != size)
 			ret = size - todo_size;
diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index a8dd956b5e8e..0cec4152f979 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -860,7 +860,7 @@ static int j1939_xtp_txnext_transmiter(struct j1939_session *session)
 				return ret;
 		}
 
-		/* fall through */
+		fallthrough;
 	case J1939_TP_CMD_CTS:
 	case 0xff: /* did some data */
 	case J1939_ETP_CMD_DPO:
@@ -1764,12 +1764,12 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
 	case J1939_ETP_CMD_DPO:
 		if (skcb->addr.type == J1939_ETP)
 			break;
-		/* fall through */
-	case J1939_TP_CMD_BAM: /* fall through */
+		fallthrough;
+	case J1939_TP_CMD_BAM:
 	case J1939_TP_CMD_CTS: /* fall through */
 		if (skcb->addr.type != J1939_ETP)
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		netdev_info(priv->ndev, "%s: 0x%p: last %02x\n", __func__,
 			    session, session->last_cmd);
@@ -1965,8 +1965,8 @@ static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb)
 	switch (cmd) {
 	case J1939_ETP_CMD_RTS:
 		extd = J1939_ETP;
-		/* fall through */
-	case J1939_TP_CMD_BAM: /* fall through */
+		fallthrough;
+	case J1939_TP_CMD_BAM:
 	case J1939_TP_CMD_RTS: /* fall through */
 		if (skcb->addr.type != extd)
 			return;
@@ -1987,7 +1987,7 @@ static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb)
 
 	case J1939_ETP_CMD_CTS:
 		extd = J1939_ETP;
-		/* fall through */
+		fallthrough;
 	case J1939_TP_CMD_CTS:
 		if (skcb->addr.type != extd)
 			return;
@@ -2014,7 +2014,7 @@ static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb)
 
 	case J1939_ETP_CMD_EOMA:
 		extd = J1939_ETP;
-		/* fall through */
+		fallthrough;
 	case J1939_TP_CMD_EOMA:
 		if (skcb->addr.type != extd)
 			return;
@@ -2050,14 +2050,14 @@ int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb)
 	switch (skcb->addr.pgn) {
 	case J1939_ETP_PGN_DAT:
 		skcb->addr.type = J1939_ETP;
-		/* fall through */
+		fallthrough;
 	case J1939_TP_PGN_DAT:
 		j1939_xtp_rx_dat(priv, skb);
 		break;
 
 	case J1939_ETP_PGN_CTL:
 		skcb->addr.type = J1939_ETP;
-		/* fall through */
+		fallthrough;
 	case J1939_TP_PGN_CTL:
 		if (skb->len < 8)
 			return 0; /* Don't care. Nothing to extract here */
diff --git a/net/ceph/ceph_hash.c b/net/ceph/ceph_hash.c
index 81e1e006c540..16a47c0eef37 100644
--- a/net/ceph/ceph_hash.c
+++ b/net/ceph/ceph_hash.c
@@ -50,35 +50,35 @@ unsigned int ceph_str_hash_rjenkins(const char *str, unsigned int length)
 	switch (len) {
 	case 11:
 		c = c + ((__u32)k[10] << 24);
-		/* fall through */
+		fallthrough;
 	case 10:
 		c = c + ((__u32)k[9] << 16);
-		/* fall through */
+		fallthrough;
 	case 9:
 		c = c + ((__u32)k[8] << 8);
 		/* the first byte of c is reserved for the length */
-		/* fall through */
+		fallthrough;
 	case 8:
 		b = b + ((__u32)k[7] << 24);
-		/* fall through */
+		fallthrough;
 	case 7:
 		b = b + ((__u32)k[6] << 16);
-		/* fall through */
+		fallthrough;
 	case 6:
 		b = b + ((__u32)k[5] << 8);
-		/* fall through */
+		fallthrough;
 	case 5:
 		b = b + k[4];
-		/* fall through */
+		fallthrough;
 	case 4:
 		a = a + ((__u32)k[3] << 24);
-		/* fall through */
+		fallthrough;
 	case 3:
 		a = a + ((__u32)k[2] << 16);
-		/* fall through */
+		fallthrough;
 	case 2:
 		a = a + ((__u32)k[1] << 8);
-		/* fall through */
+		fallthrough;
 	case 1:
 		a = a + k[0];
 		/* case 0: nothing left to add */
diff --git a/net/ceph/crush/mapper.c b/net/ceph/crush/mapper.c
index 07e5614eb3f1..7057f8db4f99 100644
--- a/net/ceph/crush/mapper.c
+++ b/net/ceph/crush/mapper.c
@@ -987,7 +987,7 @@ int crush_do_rule(const struct crush_map *map,
 		case CRUSH_RULE_CHOOSELEAF_FIRSTN:
 		case CRUSH_RULE_CHOOSE_FIRSTN:
 			firstn = 1;
-			/* fall through */
+			fallthrough;
 		case CRUSH_RULE_CHOOSELEAF_INDEP:
 		case CRUSH_RULE_CHOOSE_INDEP:
 			if (wsize == 0)
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 27d6ab11f9ee..bdfd66ba3843 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -412,7 +412,7 @@ static void ceph_sock_state_change(struct sock *sk)
 	switch (sk->sk_state) {
 	case TCP_CLOSE:
 		dout("%s TCP_CLOSE\n", __func__);
-		/* fall through */
+		fallthrough;
 	case TCP_CLOSE_WAIT:
 		dout("%s TCP_CLOSE_WAIT\n", __func__);
 		con_sock_state_closing(con);
@@ -2751,7 +2751,7 @@ more:
 			switch (ret) {
 			case -EBADMSG:
 				con->error_msg = "bad crc/signature";
-				/* fall through */
+				fallthrough;
 			case -EBADE:
 				ret = -EIO;
 				break;
diff --git a/net/ceph/mon_client.c b/net/ceph/mon_client.c
index 3d8c8015e976..d633a0aeaa55 100644
--- a/net/ceph/mon_client.c
+++ b/net/ceph/mon_client.c
@@ -1307,7 +1307,7 @@ static struct ceph_msg *mon_alloc_msg(struct ceph_connection *con,
 		 * request had a non-zero tid.  Work around this weirdness
 		 * by allocating a new message.
 		 */
-		/* fall through */
+		fallthrough;
 	case CEPH_MSG_MON_MAP:
 	case CEPH_MSG_MDS_MAP:
 	case CEPH_MSG_OSD_MAP:
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index e4fbcad6e7d8..7901ab6c79fd 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -3854,7 +3854,7 @@ static void scan_requests(struct ceph_osd *osd,
 			if (!force_resend && !force_resend_writes)
 				break;
 
-			/* fall through */
+			fallthrough;
 		case CALC_TARGET_NEED_RESEND:
 			cancel_linger_map_check(lreq);
 			/*
@@ -3891,7 +3891,7 @@ static void scan_requests(struct ceph_osd *osd,
 			     !force_resend_writes))
 				break;
 
-			/* fall through */
+			fallthrough;
 		case CALC_TARGET_NEED_RESEND:
 			cancel_map_check(req);
 			unlink_request(osd, req);
diff --git a/net/core/dev.c b/net/core/dev.c
index d42c9ea0c3c0..b9c6f31ae96e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4690,10 +4690,10 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 		break;
 	default:
 		bpf_warn_invalid_xdp_action(act);
-		/* fall through */
+		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(skb->dev, xdp_prog, act);
-		/* fall through */
+		fallthrough;
 	case XDP_DROP:
 	do_drop:
 		kfree_skb(skb);
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index b2cf9b7bb7b8..205e92e604ef 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -322,7 +322,7 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
 		err = net_hwtstamp_validate(ifr);
 		if (err)
 			return err;
-		/* fall through */
+		fallthrough;
 
 	/*
 	 *	Unknown or private ioctl
@@ -478,7 +478,7 @@ int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_c
 	case SIOCSIFTXQLEN:
 		if (!capable(CAP_NET_ADMIN))
 			return -EPERM;
-		/* fall through */
+		fallthrough;
 	/*
 	 *	These ioctl calls:
 	 *	- require local superuser power.
@@ -503,7 +503,7 @@ int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_c
 	case SIOCSHWTSTAMP:
 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
-		/* fall through */
+		fallthrough;
 	case SIOCBONDSLAVEINFOQUERY:
 	case SIOCBONDINFOQUERY:
 		dev_load(net, ifr->ifr_name);
diff --git a/net/core/devlink.c b/net/core/devlink.c
index e5feb87beca7..80ec1cd81c64 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -6196,8 +6196,8 @@ devlink_trap_action_get_from_info(struct genl_info *info,
 
 	val = nla_get_u8(info->attrs[DEVLINK_ATTR_TRAP_ACTION]);
 	switch (val) {
-	case DEVLINK_TRAP_ACTION_DROP: /* fall-through */
-	case DEVLINK_TRAP_ACTION_TRAP: /* fall-through */
+	case DEVLINK_TRAP_ACTION_DROP:
+	case DEVLINK_TRAP_ACTION_TRAP:
 	case DEVLINK_TRAP_ACTION_MIRROR:
 		*p_trap_action = val;
 		break;
diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c
index b09bebeadf0b..9704522b0872 100644
--- a/net/core/drop_monitor.c
+++ b/net/core/drop_monitor.c
@@ -1189,7 +1189,7 @@ static int net_dm_alert_mode_get_from_info(struct genl_info *info,
 	val = nla_get_u8(info->attrs[NET_DM_ATTR_ALERT_MODE]);
 
 	switch (val) {
-	case NET_DM_ALERT_MODE_SUMMARY: /* fall-through */
+	case NET_DM_ALERT_MODE_SUMMARY:
 	case NET_DM_ALERT_MODE_PACKET:
 		*p_alert_mode = val;
 		break;
diff --git a/net/core/filter.c b/net/core/filter.c
index b2df52086445..1f647ab986b6 100644
--- a/