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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/tty/hvc/hvsi_lib.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to '')
-rw-r--r--drivers/tty/hvc/hvsi_lib.c424
1 files changed, 424 insertions, 0 deletions
diff --git a/drivers/tty/hvc/hvsi_lib.c b/drivers/tty/hvc/hvsi_lib.c
new file mode 100644
index 000000000..09289c815
--- /dev/null
+++ b/drivers/tty/hvc/hvsi_lib.c
@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/console.h>
+#include <asm/hvsi.h>
+
+#include "hvc_console.h"
+
+static int hvsi_send_packet(struct hvsi_priv *pv, struct hvsi_header *packet)
+{
+ packet->seqno = cpu_to_be16(atomic_inc_return(&pv->seqno));
+
+ /* Assumes that always succeeds, works in practice */
+ return pv->put_chars(pv->termno, (char *)packet, packet->len);
+}
+
+static void hvsi_start_handshake(struct hvsi_priv *pv)
+{
+ struct hvsi_query q;
+
+ /* Reset state */
+ pv->established = 0;
+ atomic_set(&pv->seqno, 0);
+
+ pr_devel("HVSI@%x: Handshaking started\n", pv->termno);
+
+ /* Send version query */
+ q.hdr.type = VS_QUERY_PACKET_HEADER;
+ q.hdr.len = sizeof(struct hvsi_query);
+ q.verb = cpu_to_be16(VSV_SEND_VERSION_NUMBER);
+ hvsi_send_packet(pv, &q.hdr);
+}
+
+static int hvsi_send_close(struct hvsi_priv *pv)
+{
+ struct hvsi_control ctrl;
+
+ pv->established = 0;
+
+ ctrl.hdr.type = VS_CONTROL_PACKET_HEADER;
+ ctrl.hdr.len = sizeof(struct hvsi_control);
+ ctrl.verb = cpu_to_be16(VSV_CLOSE_PROTOCOL);
+ return hvsi_send_packet(pv, &ctrl.hdr);
+}
+
+static void hvsi_cd_change(struct hvsi_priv *pv, int cd)
+{
+ if (cd)
+ pv->mctrl |= TIOCM_CD;
+ else {
+ pv->mctrl &= ~TIOCM_CD;
+
+ /* We copy the existing hvsi driver semantics
+ * here which are to trigger a hangup when
+ * we get a carrier loss.
+ * Closing our connection to the server will
+ * do just that.
+ */
+ if (!pv->is_console && pv->opened) {
+ pr_devel("HVSI@%x Carrier lost, hanging up !\n",
+ pv->termno);
+ hvsi_send_close(pv);
+ }
+ }
+}
+
+static void hvsi_got_control(struct hvsi_priv *pv)
+{
+ struct hvsi_control *pkt = (struct hvsi_control *)pv->inbuf;
+
+ switch (be16_to_cpu(pkt->verb)) {
+ case VSV_CLOSE_PROTOCOL:
+ /* We restart the handshaking */
+ hvsi_start_handshake(pv);
+ break;
+ case VSV_MODEM_CTL_UPDATE:
+ /* Transition of carrier detect */
+ hvsi_cd_change(pv, be32_to_cpu(pkt->word) & HVSI_TSCD);
+ break;
+ }
+}
+
+static void hvsi_got_query(struct hvsi_priv *pv)
+{
+ struct hvsi_query *pkt = (struct hvsi_query *)pv->inbuf;
+ struct hvsi_query_response r;
+
+ /* We only handle version queries */
+ if (be16_to_cpu(pkt->verb) != VSV_SEND_VERSION_NUMBER)
+ return;
+
+ pr_devel("HVSI@%x: Got version query, sending response...\n",
+ pv->termno);
+
+ /* Send version response */
+ r.hdr.type = VS_QUERY_RESPONSE_PACKET_HEADER;
+ r.hdr.len = sizeof(struct hvsi_query_response);
+ r.verb = cpu_to_be16(VSV_SEND_VERSION_NUMBER);
+ r.u.version = HVSI_VERSION;
+ r.query_seqno = pkt->hdr.seqno;
+ hvsi_send_packet(pv, &r.hdr);
+
+ /* Assume protocol is open now */
+ pv->established = 1;
+}
+
+static void hvsi_got_response(struct hvsi_priv *pv)
+{
+ struct hvsi_query_response *r =
+ (struct hvsi_query_response *)pv->inbuf;
+
+ switch(r->verb) {
+ case VSV_SEND_MODEM_CTL_STATUS:
+ hvsi_cd_change(pv, be32_to_cpu(r->u.mctrl_word) & HVSI_TSCD);
+ pv->mctrl_update = 1;
+ break;
+ }
+}
+
+static int hvsi_check_packet(struct hvsi_priv *pv)
+{
+ u8 len, type;
+
+ /* Check header validity. If it's invalid, we ditch
+ * the whole buffer and hope we eventually resync
+ */
+ if (pv->inbuf[0] < 0xfc) {
+ pv->inbuf_len = pv->inbuf_pktlen = 0;
+ return 0;
+ }
+ type = pv->inbuf[0];
+ len = pv->inbuf[1];
+
+ /* Packet incomplete ? */
+ if (pv->inbuf_len < len)
+ return 0;
+
+ pr_devel("HVSI@%x: Got packet type %x len %d bytes:\n",
+ pv->termno, type, len);
+
+ /* We have a packet, yay ! Handle it */
+ switch(type) {
+ case VS_DATA_PACKET_HEADER:
+ pv->inbuf_pktlen = len - 4;
+ pv->inbuf_cur = 4;
+ return 1;
+ case VS_CONTROL_PACKET_HEADER:
+ hvsi_got_control(pv);
+ break;
+ case VS_QUERY_PACKET_HEADER:
+ hvsi_got_query(pv);
+ break;
+ case VS_QUERY_RESPONSE_PACKET_HEADER:
+ hvsi_got_response(pv);
+ break;
+ }
+
+ /* Swallow packet and retry */
+ pv->inbuf_len -= len;
+ memmove(pv->inbuf, &pv->inbuf[len], pv->inbuf_len);
+ return 1;
+}
+
+static int hvsi_get_packet(struct hvsi_priv *pv)
+{
+ /* If we have room in the buffer, ask HV for more */
+ if (pv->inbuf_len < HVSI_INBUF_SIZE)
+ pv->inbuf_len += pv->get_chars(pv->termno,
+ &pv->inbuf[pv->inbuf_len],
+ HVSI_INBUF_SIZE - pv->inbuf_len);
+ /*
+ * If we have at least 4 bytes in the buffer, check for
+ * a full packet and retry
+ */
+ if (pv->inbuf_len >= 4)
+ return hvsi_check_packet(pv);
+ return 0;
+}
+
+int hvsilib_get_chars(struct hvsi_priv *pv, char *buf, int count)
+{
+ unsigned int tries, read = 0;
+
+ if (WARN_ON(!pv))
+ return -ENXIO;
+
+ /* If we aren't open, don't do anything in order to avoid races
+ * with connection establishment. The hvc core will call this
+ * before we have returned from notifier_add(), and we need to
+ * avoid multiple users playing with the receive buffer
+ */
+ if (!pv->opened)
+ return 0;
+
+ /* We try twice, once with what data we have and once more
+ * after we try to fetch some more from the hypervisor
+ */
+ for (tries = 1; count && tries < 2; tries++) {
+ /* Consume existing data packet */
+ if (pv->inbuf_pktlen) {
+ unsigned int l = min(count, (int)pv->inbuf_pktlen);
+ memcpy(&buf[read], &pv->inbuf[pv->inbuf_cur], l);
+ pv->inbuf_cur += l;
+ pv->inbuf_pktlen -= l;
+ count -= l;
+ read += l;
+ }
+ if (count == 0)
+ break;
+
+ /* Data packet fully consumed, move down remaning data */
+ if (pv->inbuf_cur) {
+ pv->inbuf_len -= pv->inbuf_cur;
+ memmove(pv->inbuf, &pv->inbuf[pv->inbuf_cur],
+ pv->inbuf_len);
+ pv->inbuf_cur = 0;
+ }
+
+ /* Try to get another packet */
+ if (hvsi_get_packet(pv))
+ tries--;
+ }
+ if (!pv->established) {
+ pr_devel("HVSI@%x: returning -EPIPE\n", pv->termno);
+ return -EPIPE;
+ }
+ return read;
+}
+
+int hvsilib_put_chars(struct hvsi_priv *pv, const char *buf, int count)
+{
+ struct hvsi_data dp;
+ int rc, adjcount = min(count, HVSI_MAX_OUTGOING_DATA);
+
+ if (WARN_ON(!pv))
+ return -ENODEV;
+
+ dp.hdr.type = VS_DATA_PACKET_HEADER;
+ dp.hdr.len = adjcount + sizeof(struct hvsi_header);
+ memcpy(dp.data, buf, adjcount);
+ rc = hvsi_send_packet(pv, &dp.hdr);
+ if (rc <= 0)
+ return rc;
+ return adjcount;
+}
+
+static void maybe_msleep(unsigned long ms)
+{
+ /* During early boot, IRQs are disabled, use mdelay */
+ if (irqs_disabled())
+ mdelay(ms);
+ else
+ msleep(ms);
+}
+
+int hvsilib_read_mctrl(struct hvsi_priv *pv)
+{
+ struct hvsi_query q;
+ int rc, timeout;
+
+ pr_devel("HVSI@%x: Querying modem control status...\n",
+ pv->termno);
+
+ pv->mctrl_update = 0;
+ q.hdr.type = VS_QUERY_PACKET_HEADER;
+ q.hdr.len = sizeof(struct hvsi_query);
+ q.verb = cpu_to_be16(VSV_SEND_MODEM_CTL_STATUS);
+ rc = hvsi_send_packet(pv, &q.hdr);
+ if (rc <= 0) {
+ pr_devel("HVSI@%x: Error %d...\n", pv->termno, rc);
+ return rc;
+ }
+
+ /* Try for up to 200ms */
+ for (timeout = 0; timeout < 20; timeout++) {
+ if (!pv->established)
+ return -ENXIO;
+ if (pv->mctrl_update)
+ return 0;
+ if (!hvsi_get_packet(pv))
+ maybe_msleep(10);
+ }
+ return -EIO;
+}
+
+int hvsilib_write_mctrl(struct hvsi_priv *pv, int dtr)
+{
+ struct hvsi_control ctrl;
+ unsigned short mctrl;
+
+ mctrl = pv->mctrl;
+ if (dtr)
+ mctrl |= TIOCM_DTR;
+ else
+ mctrl &= ~TIOCM_DTR;
+ if (mctrl == pv->mctrl)
+ return 0;
+ pv->mctrl = mctrl;
+
+ pr_devel("HVSI@%x: %s DTR...\n", pv->termno,
+ dtr ? "Setting" : "Clearing");
+
+ ctrl.hdr.type = VS_CONTROL_PACKET_HEADER,
+ ctrl.hdr.len = sizeof(struct hvsi_control);
+ ctrl.verb = cpu_to_be16(VSV_SET_MODEM_CTL);
+ ctrl.mask = cpu_to_be32(HVSI_TSDTR);
+ ctrl.word = cpu_to_be32(dtr ? HVSI_TSDTR : 0);
+ return hvsi_send_packet(pv, &ctrl.hdr);
+}
+
+void hvsilib_establish(struct hvsi_priv *pv)
+{
+ int timeout;
+
+ pr_devel("HVSI@%x: Establishing...\n", pv->termno);
+
+ /* Try for up to 200ms, there can be a packet to
+ * start the process waiting for us...
+ */
+ for (timeout = 0; timeout < 20; timeout++) {
+ if (pv->established)
+ goto established;
+ if (!hvsi_get_packet(pv))
+ maybe_msleep(10);
+ }
+
+ /* Failed, send a close connection packet just
+ * in case
+ */
+ pr_devel("HVSI@%x: ... sending close\n", pv->termno);
+
+ hvsi_send_close(pv);
+
+ /* Then restart handshake */
+
+ pr_devel("HVSI@%x: ... restarting handshake\n", pv->termno);
+
+ hvsi_start_handshake(pv);
+
+ pr_devel("HVSI@%x: ... waiting handshake\n", pv->termno);
+
+ /* Try for up to 400ms */
+ for (timeout = 0; timeout < 40; timeout++) {
+ if (pv->established)
+ goto established;
+ if (!hvsi_get_packet(pv))
+ maybe_msleep(10);
+ }
+
+ if (!pv->established) {
+ pr_devel("HVSI@%x: Timeout handshaking, giving up !\n",
+ pv->termno);
+ return;
+ }
+ established:
+ /* Query modem control lines */
+
+ pr_devel("HVSI@%x: ... established, reading mctrl\n", pv->termno);
+
+ hvsilib_read_mctrl(pv);
+
+ /* Set our own DTR */
+
+ pr_devel("HVSI@%x: ... setting mctrl\n", pv->termno);
+
+ hvsilib_write_mctrl(pv, 1);
+
+ /* Set the opened flag so reads are allowed */
+ wmb();
+ pv->opened = 1;
+}
+
+int hvsilib_open(struct hvsi_priv *pv, struct hvc_struct *hp)
+{
+ pr_devel("HVSI@%x: open !\n", pv->termno);
+
+ /* Keep track of the tty data structure */
+ pv->tty = tty_port_tty_get(&hp->port);
+
+ hvsilib_establish(pv);
+
+ return 0;
+}
+
+void hvsilib_close(struct hvsi_priv *pv, struct hvc_struct *hp)
+{
+ unsigned long flags;
+
+ pr_devel("HVSI@%x: close !\n", pv->termno);
+
+ if (!pv->is_console) {
+ pr_devel("HVSI@%x: Not a console, tearing down\n",
+ pv->termno);
+
+ /* Clear opened, synchronize with khvcd */
+ spin_lock_irqsave(&hp->lock, flags);
+ pv->opened = 0;
+ spin_unlock_irqrestore(&hp->lock, flags);
+
+ /* Clear our own DTR */
+ if (!pv->tty || (pv->tty->termios.c_cflag & HUPCL))
+ hvsilib_write_mctrl(pv, 0);
+
+ /* Tear down the connection */
+ hvsi_send_close(pv);
+ }
+
+ tty_kref_put(pv->tty);
+ pv->tty = NULL;
+}
+
+void hvsilib_init(struct hvsi_priv *pv,
+ int (*get_chars)(uint32_t termno, char *buf, int count),
+ int (*put_chars)(uint32_t termno, const char *buf,
+ int count),
+ int termno, int is_console)
+{
+ memset(pv, 0, sizeof(*pv));
+ pv->get_chars = get_chars;
+ pv->put_chars = put_chars;
+ pv->termno = termno;
+ pv->is_console = is_console;
+}