1 files changed, 792 insertions, 0 deletions

diff --git a/arch/sparc64/kernel/viohs.c b/arch/sparc64/kernel/viohs.c
new file mode 100644
index 00000000000..15613add45d
--- /dev/null
+++ b/arch/sparc64/kernel/viohs.c
@@ -0,0 +1,792 @@
+/* viohs.c: LDOM Virtual I/O handshake helper layer.
+ *
+ * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include <asm/ldc.h>
+#include <asm/vio.h>
+
+int vio_ldc_send(struct vio_driver_state *vio, void *data, int len)
+{
+	int err, limit = 1000;
+
+	err = -EINVAL;
+	while (limit-- > 0) {
+		err = ldc_write(vio->lp, data, len);
+		if (!err || (err != -EAGAIN))
+			break;
+		udelay(1);
+	}
+
+	return err;
+}
+EXPORT_SYMBOL(vio_ldc_send);
+
+static int send_ctrl(struct vio_driver_state *vio,
+		     struct vio_msg_tag *tag, int len)
+{
+	tag->sid = vio_send_sid(vio);
+	return vio_ldc_send(vio, tag, len);
+}
+
+static void init_tag(struct vio_msg_tag *tag, u8 type, u8 stype, u16 stype_env)
+{
+	tag->type = type;
+	tag->stype = stype;
+	tag->stype_env = stype_env;
+}
+
+static int send_version(struct vio_driver_state *vio, u16 major, u16 minor)
+{
+	struct vio_ver_info pkt;
+
+	vio->_local_sid = (u32) sched_clock();
+
+	memset(&pkt, 0, sizeof(pkt));
+	init_tag(&pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_VER_INFO);
+	pkt.major = major;
+	pkt.minor = minor;
+	pkt.dev_class = vio->dev_class;
+
+	viodbg(HS, "SEND VERSION INFO maj[%u] min[%u] devclass[%u]\n",
+	       major, minor, vio->dev_class);
+
+	return send_ctrl(vio, &pkt.tag, sizeof(pkt));
+}
+
+static int start_handshake(struct vio_driver_state *vio)
+{
+	int err;
+
+	viodbg(HS, "START HANDSHAKE\n");
+
+	vio->hs_state = VIO_HS_INVALID;
+
+	err = send_version(vio,
+			   vio->ver_table[0].major,
+			   vio->ver_table[0].minor);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+void vio_link_state_change(struct vio_driver_state *vio, int event)
+{
+	if (event == LDC_EVENT_UP) {
+		vio->hs_state = VIO_HS_INVALID;
+
+		switch (vio->dev_class) {
+		case VDEV_NETWORK:
+		case VDEV_NETWORK_SWITCH:
+			vio->dr_state = (VIO_DR_STATE_TXREQ |
+					 VIO_DR_STATE_RXREQ);
+			break;
+
+		case VDEV_DISK:
+			vio->dr_state = VIO_DR_STATE_TXREQ;
+			break;
+		case VDEV_DISK_SERVER:
+			vio->dr_state = VIO_DR_STATE_RXREQ;
+			break;
+		}
+		start_handshake(vio);
+	}
+}
+EXPORT_SYMBOL(vio_link_state_change);
+
+static int handshake_failure(struct vio_driver_state *vio)
+{
+	struct vio_dring_state *dr;
+
+	/* XXX Put policy here...  Perhaps start a timer to fire
+	 * XXX in 100 ms, which will bring the link up and retry
+	 * XXX the handshake.
+	 */
+
+	viodbg(HS, "HANDSHAKE FAILURE\n");
+
+	vio->dr_state &= ~(VIO_DR_STATE_TXREG |
+			   VIO_DR_STATE_RXREG);
+
+	dr = &vio->drings[VIO_DRIVER_RX_RING];
+	memset(dr, 0, sizeof(*dr));
+
+	kfree(vio->desc_buf);
+	vio->desc_buf = NULL;
+	vio->desc_buf_len = 0;
+
+	vio->hs_state = VIO_HS_INVALID;
+
+	return -ECONNRESET;
+}
+
+static int process_unknown(struct vio_driver_state *vio, void *arg)
+{
+	struct vio_msg_tag *pkt = arg;
+
+	viodbg(HS, "UNKNOWN CONTROL [%02x:%02x:%04x:%08x]\n",
+	       pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
+
+	printk(KERN_ERR "vio: ID[%lu] Resetting connection.\n",
+	       vio->vdev->channel_id);
+
+	ldc_disconnect(vio->lp);
+
+	return -ECONNRESET;
+}
+
+static int send_dreg(struct vio_driver_state *vio)
+{
+	struct vio_dring_state *dr = &vio->drings[VIO_DRIVER_TX_RING];
+	union {
+		struct vio_dring_register pkt;
+		char all[sizeof(struct vio_dring_register) +
+			 (sizeof(struct ldc_trans_cookie) *
+			  dr->ncookies)];
+	} u;
+	int i;
+
+	memset(&u, 0, sizeof(u));
+	init_tag(&u.pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_DRING_REG);
+	u.pkt.dring_ident = 0;
+	u.pkt.num_descr = dr->num_entries;
+	u.pkt.descr_size = dr->entry_size;
+	u.pkt.options = VIO_TX_DRING;
+	u.pkt.num_cookies = dr->ncookies;
+
+	viodbg(HS, "SEND DRING_REG INFO ndesc[%u] dsz[%u] opt[0x%x] "
+	       "ncookies[%u]\n",
+	       u.pkt.num_descr, u.pkt.descr_size, u.pkt.options,
+	       u.pkt.num_cookies);
+
+	for (i = 0; i < dr->ncookies; i++) {
+		u.pkt.cookies[i] = dr->cookies[i];
+
+		viodbg(HS, "DRING COOKIE(%d) [%016llx:%016llx]\n",
+		       i,
+		       (unsigned long long) u.pkt.cookies[i].cookie_addr,
+		       (unsigned long long) u.pkt.cookies[i].cookie_size);
+	}
+
+	return send_ctrl(vio, &u.pkt.tag, sizeof(u));
+}
+
+static int send_rdx(struct vio_driver_state *vio)
+{
+	struct vio_rdx pkt;
+
+	memset(&pkt, 0, sizeof(pkt));
+
+	init_tag(&pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_RDX);
+
+	viodbg(HS, "SEND RDX INFO\n");
+
+	return send_ctrl(vio, &pkt.tag, sizeof(pkt));
+}
+
+static int send_attr(struct vio_driver_state *vio)
+{
+	return vio->ops->send_attr(vio);
+}
+
+static struct vio_version *find_by_major(struct vio_driver_state *vio,
+					 u16 major)
+{
+	struct vio_version *ret = NULL;
+	int i;
+
+	for (i = 0; i < vio->ver_table_entries; i++) {
+		struct vio_version *v = &vio->ver_table[i];
+		if (v->major <= major) {
+			ret = v;
+			break;
+		}
+	}
+	return ret;
+}
+
+static int process_ver_info(struct vio_driver_state *vio,
+			    struct vio_ver_info *pkt)
+{
+	struct vio_version *vap;
+	int err;
+
+	viodbg(HS, "GOT VERSION INFO maj[%u] min[%u] devclass[%u]\n",
+	       pkt->major, pkt->minor, pkt->dev_class);
+
+	if (vio->hs_state != VIO_HS_INVALID) {
+		/* XXX Perhaps invoke start_handshake? XXX */
+		memset(&vio->ver, 0, sizeof(vio->ver));
+		vio->hs_state = VIO_HS_INVALID;
+	}
+
+	vap = find_by_major(vio, pkt->major);
+
+	vio->_peer_sid = pkt->tag.sid;
+
+	if (!vap) {
+		pkt->tag.stype = VIO_SUBTYPE_NACK;
+		pkt->major = 0;
+		pkt->minor = 0;
+		viodbg(HS, "SEND VERSION NACK maj[0] min[0]\n");
+		err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
+	} else if (vap->major != pkt->major) {
+		pkt->tag.stype = VIO_SUBTYPE_NACK;
+		pkt->major = vap->major;
+		pkt->minor = vap->minor;
+		viodbg(HS, "SEND VERSION NACK maj[%u] min[%u]\n",
+		       pkt->major, pkt->minor);
+		err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
+	} else {
+		struct vio_version ver = {
+			.major = pkt->major,
+			.minor = pkt->minor,
+		};
+		if (ver.minor > vap->minor)
+			ver.minor = vap->minor;
+		pkt->minor = ver.minor;
+		pkt->tag.stype = VIO_SUBTYPE_ACK;
+		viodbg(HS, "SEND VERSION ACK maj[%u] min[%u]\n",
+		       pkt->major, pkt->minor);
+		err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
+		if (err > 0) {
+			vio->ver = ver;
+			vio->hs_state = VIO_HS_GOTVERS;
+		}
+	}
+	if (err < 0)
+		return handshake_failure(vio);
+
+	return 0;
+}
+
+static int process_ver_ack(struct vio_driver_state *vio,
+			   struct vio_ver_info *pkt)
+{
+	viodbg(HS, "GOT VERSION ACK maj[%u] min[%u] devclass[%u]\n",
+	       pkt->major, pkt->minor, pkt->dev_class);
+
+	if (vio->hs_state & VIO_HS_GOTVERS) {
+		if (vio->ver.major != pkt->major ||
+		    vio->ver.minor != pkt->minor) {
+			pkt->tag.stype = VIO_SUBTYPE_NACK;
+			(void) send_ctrl(vio, &pkt->tag, sizeof(*pkt));
+			return handshake_failure(vio);
+		}
+	} else {
+		vio->ver.major = pkt->major;
+		vio->ver.minor = pkt->minor;
+		vio->hs_state = VIO_HS_GOTVERS;
+	}
+
+	switch (vio->dev_class) {
+	case VDEV_NETWORK:
+	case VDEV_DISK:
+		if (send_attr(vio) < 0)
+			return handshake_failure(vio);
+		break;
+
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int process_ver_nack(struct vio_driver_state *vio,
+			    struct vio_ver_info *pkt)
+{
+	struct vio_version *nver;
+
+	viodbg(HS, "GOT VERSION NACK maj[%u] min[%u] devclass[%u]\n",
+	       pkt->major, pkt->minor, pkt->dev_class);
+
+	if ((pkt->major == 0 && pkt->minor == 0) ||
+	    !(nver = find_by_major(vio, pkt->major)))
+		return handshake_failure(vio);
+
+	if (send_version(vio, nver->major, nver->minor) < 0)
+		return handshake_failure(vio);
+
+	return 0;
+}
+
+static int process_ver(struct vio_driver_state *vio, struct vio_ver_info *pkt)
+{
+	switch (pkt->tag.stype) {
+	case VIO_SUBTYPE_INFO:
+		return process_ver_info(vio, pkt);
+
+	case VIO_SUBTYPE_ACK:
+		return process_ver_ack(vio, pkt);
+
+	case VIO_SUBTYPE_NACK:
+		return process_ver_nack(vio, pkt);
+
+	default:
+		return handshake_failure(vio);
+	};
+}
+
+static int process_attr(struct vio_driver_state *vio, void *pkt)
+{
+	int err;
+
+	if (!(vio->hs_state & VIO_HS_GOTVERS))
+		return handshake_failure(vio);
+
+	err = vio->ops->handle_attr(vio, pkt);
+	if (err < 0) {
+		return handshake_failure(vio);
+	} else {
+		vio->hs_state |= VIO_HS_GOT_ATTR;
+
+		if ((vio->dr_state & VIO_DR_STATE_TXREQ) &&
+		    !(vio->hs_state & VIO_HS_SENT_DREG)) {
+			if (send_dreg(vio) < 0)
+				return handshake_failure(vio);
+
+			vio->hs_state |= VIO_HS_SENT_DREG;
+		}
+	}
+	return 0;
+}
+
+static int all_drings_registered(struct vio_driver_state *vio)
+{
+	int need_rx, need_tx;
+
+	need_rx = (vio->dr_state & VIO_DR_STATE_RXREQ);
+	need_tx = (vio->dr_state & VIO_DR_STATE_TXREQ);
+
+	if (need_rx &&
+	    !(vio->dr_state & VIO_DR_STATE_RXREG))
+		return 0;
+
+	if (need_tx &&
+	    !(vio->dr_state & VIO_DR_STATE_TXREG))
+		return 0;
+
+	return 1;
+}
+
+static int process_dreg_info(struct vio_driver_state *vio,
+			     struct vio_dring_register *pkt)
+{
+	struct vio_dring_state *dr;
+	int i, len;
+
+	viodbg(HS, "GOT DRING_REG INFO ident[%llx] "
+	       "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
+	       (unsigned long long) pkt->dring_ident,
+	       pkt->num_descr, pkt->descr_size, pkt->options,
+	       pkt->num_cookies);
+
+	if (!(vio->dr_state & VIO_DR_STATE_RXREQ))
+		goto send_nack;
+
+	if (vio->dr_state & VIO_DR_STATE_RXREG)
+		goto send_nack;
+
+	vio->desc_buf = kzalloc(pkt->descr_size, GFP_ATOMIC);
+	if (!vio->desc_buf)
+		goto send_nack;
+
+	vio->desc_buf_len = pkt->descr_size;
+
+	dr = &vio->drings[VIO_DRIVER_RX_RING];
+
+	dr->num_entries = pkt->num_descr;
+	dr->entry_size = pkt->descr_size;
+	dr->ncookies = pkt->num_cookies;
+	for (i = 0; i < dr->ncookies; i++) {
+		dr->cookies[i] = pkt->cookies[i];
+
+		viodbg(HS, "DRING COOKIE(%d) [%016llx:%016llx]\n",
+		       i,
+		       (unsigned long long)
+		       pkt->cookies[i].cookie_addr,
+		       (unsigned long long)
+		       pkt->cookies[i].cookie_size);
+	}
+
+	pkt->tag.stype = VIO_SUBTYPE_ACK;
+	pkt->dring_ident = ++dr->ident;
+
+	viodbg(HS, "SEND DRING_REG ACK ident[%llx]\n",
+	       (unsigned long long) pkt->dring_ident);
+
+	len = (sizeof(*pkt) +
+	       (dr->ncookies * sizeof(struct ldc_trans_cookie)));
+	if (send_ctrl(vio, &pkt->tag, len) < 0)
+		goto send_nack;
+
+	vio->dr_state |= VIO_DR_STATE_RXREG;
+
+	return 0;
+
+send_nack:
+	pkt->tag.stype = VIO_SUBTYPE_NACK;
+	viodbg(HS, "SEND DRING_REG NACK\n");
+	(void) send_ctrl(vio, &pkt->tag, sizeof(*pkt));
+
+	return handshake_failure(vio);
+}
+
+static int process_dreg_ack(struct vio_driver_state *vio,
+			    struct vio_dring_register *pkt)
+{
+	struct vio_dring_state *dr;
+
+	viodbg(HS, "GOT DRING_REG ACK ident[%llx] "
+	       "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
+	       (unsigned long long) pkt->dring_ident,
+	       pkt->num_descr, pkt->descr_size, pkt->options,
+	       pkt->num_cookies);
+
+	dr = &vio->drings[VIO_DRIVER_TX_RING];
+
+	if (!(vio->dr_state & VIO_DR_STATE_TXREQ))
+		return handshake_failure(vio);
+
+	dr->ident = pkt->dring_ident;
+	vio->dr_state |= VIO_DR_STATE_TXREG;
+
+	if (all_drings_registered(vio)) {
+		if (send_rdx(vio) < 0)
+			return handshake_failure(vio);
+		vio->hs_state = VIO_HS_SENT_RDX;
+	}
+	return 0;
+}
+
+static int process_dreg_nack(struct vio_driver_state *vio,
+			     struct vio_dring_register *pkt)
+{
+	viodbg(HS, "GOT DRING_REG NACK ident[%llx] "
+	       "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
+	       (unsigned long long) pkt->dring_ident,
+	       pkt->num_descr, pkt->descr_size, pkt->options,
+	       pkt->num_cookies);
+
+	return handshake_failure(vio);
+}
+
+static int process_dreg(struct vio_driver_state *vio,
+			struct vio_dring_register *pkt)
+{
+	if (!(vio->hs_state & VIO_HS_GOTVERS))
+		return handshake_failure(vio);
+
+	switch (pkt->tag.stype) {
+	case VIO_SUBTYPE_INFO:
+		return process_dreg_info(vio, pkt);
+
+	case VIO_SUBTYPE_ACK:
+		return process_dreg_ack(vio, pkt);
+
+	case VIO_SUBTYPE_NACK:
+		return process_dreg_nack(vio, pkt);
+
+	default:
+		return handshake_failure(vio);
+	}
+}
+
+static int process_dunreg(struct vio_driver_state *vio,
+			  struct vio_dring_unregister *pkt)
+{
+	struct vio_dring_state *dr = &vio->drings[VIO_DRIVER_RX_RING];
+
+	viodbg(HS, "GOT DRING_UNREG\n");
+
+	if (pkt->dring_ident != dr->ident)
+		return 0;
+
+	vio->dr_state &= ~VIO_DR_STATE_RXREG;
+
+	memset(dr, 0, sizeof(*dr));
+
+	kfree(vio->desc_buf);
+	vio->desc_buf = NULL;
+	vio->desc_buf_len = 0;
+
+	return 0;
+}
+
+static int process_rdx_info(struct vio_driver_state *vio, struct vio_rdx *pkt)
+{
+	viodbg(HS, "GOT RDX INFO\n");
+
+	pkt->tag.stype = VIO_SUBTYPE_ACK;
+	viodbg(HS, "SEND RDX ACK\n");
+	if (send_ctrl(vio, &pkt->tag, sizeof(*pkt)) < 0)
+		return handshake_failure(vio);
+
+	vio->hs_state |= VIO_HS_SENT_RDX_ACK;
+	return 0;
+}
+
+static int process_rdx_ack(struct vio_driver_state *vio, struct vio_rdx *pkt)
+{
+	viodbg(HS, "GOT RDX ACK\n");
+
+	if (!(vio->hs_state & VIO_HS_SENT_RDX))
+		return handshake_failure(vio);
+
+	vio->hs_state |= VIO_HS_GOT_RDX_ACK;
+	return 0;
+}
+
+static int process_rdx_nack(struct vio_driver_state *vio, struct vio_rdx *pkt)
+{
+	viodbg(HS, "GOT RDX NACK\n");
+
+	return handshake_failure(vio);
+}
+
+static int process_rdx(struct vio_driver_state *vio, struct vio_rdx *pkt)
+{
+	if (!all_drings_registered(vio))
+		handshake_failure(vio);
+
+	switch (pkt->tag.stype) {
+	case VIO_SUBTYPE_INFO:
+		return process_rdx_info(vio, pkt);
+
+	case VIO_SUBTYPE_ACK:
+		return process_rdx_ack(vio, pkt);
+
+	case VIO_SUBTYPE_NACK:
+		return process_rdx_nack(vio, pkt);
+
+	default:
+		return handshake_failure(vio);
+	}
+}
+
+int vio_control_pkt_engine(struct vio_driver_state *vio, void *pkt)
+{
+	struct vio_msg_tag *tag = pkt;
+	u8 prev_state = vio->hs_state;
+	int err;
+
+	switch (tag->stype_env) {
+	case VIO_VER_INFO:
+		err = process_ver(vio, pkt);
+		break;
+
+	case VIO_ATTR_INFO:
+		err = process_attr(vio, pkt);
+		break;
+
+	case VIO_DRING_REG:
+		err = process_dreg(vio, pkt);
+		break;
+
+	case VIO_DRING_UNREG:
+		err = process_dunreg(vio, pkt);
+		break;
+
+	case VIO_RDX:
+		err = process_rdx(vio, pkt);
+		break;
+
+	default:
+		err = process_unknown(vio, pkt);
+		break;
+	}
+	if (!err &&
+	    vio->hs_state != prev_state &&
+	    (vio->hs_state & VIO_HS_COMPLETE))
+		vio->ops->handshake_complete(vio);
+
+	return err;
+}
+EXPORT_SYMBOL(vio_control_pkt_engine);
+
+void vio_conn_reset(struct vio_driver_state *vio)
+{
+}
+EXPORT_SYMBOL(vio_conn_reset);
+
+/* The issue is that the Solaris virtual disk server just mirrors the
+ * SID values it gets from the client peer.  So we work around that
+ * here in vio_{validate,send}_sid() so that the drivers don't need
+ * to be aware of this crap.
+ */
+int vio_validate_sid(struct vio_driver_state *vio, struct vio_msg_tag *tp)
+{
+	u32 sid;
+
+	/* Always let VERSION+INFO packets through unchecked, they
+	 * define the new SID.
+	 */
+	if (tp->type == VIO_TYPE_CTRL &&
+	    tp->stype == VIO_SUBTYPE_INFO &&
+	    tp->stype_env == VIO_VER_INFO)
+		return 0;
+
+	/* Ok, now figure out which SID to use.  */
+	switch (vio->dev_class) {
+	case VDEV_NETWORK:
+	case VDEV_NETWORK_SWITCH:
+	case VDEV_DISK_SERVER:
+	default:
+		sid = vio->_peer_sid;
+		break;
+
+	case VDEV_DISK:
+		sid = vio->_local_sid;
+		break;
+	}
+
+	if (sid == tp->sid)
+		return 0;
+	viodbg(DATA, "BAD SID tag->sid[%08x] peer_sid[%08x] local_sid[%08x]\n",
+	       tp->sid, vio->_peer_sid, vio->_local_sid);
+	return -EINVAL;
+}
+EXPORT_SYMBOL(vio_validate_sid);
+
+u32 vio_send_sid(struct vio_driver_state *vio)
+{
+	switch (vio->dev_class) {
+	case VDEV_NETWORK:
+	case VDEV_NETWORK_SWITCH:
+	case VDEV_DISK:
+	default:
+		return vio->_local_sid;
+
+	case VDEV_DISK_SERVER:
+		return vio->_peer_sid;
+	}
+}
+EXPORT_SYMBOL(vio_send_sid);
+
+extern int vio_ldc_alloc(struct vio_driver_state *vio,
+			 struct ldc_channel_config *base_cfg,
+			 void *event_arg)
+{
+	struct ldc_channel_config cfg = *base_cfg;
+	struct ldc_channel *lp;
+
+	cfg.tx_irq = vio->vdev->tx_irq;
+	cfg.rx_irq = vio->vdev->rx_irq;
+
+	lp = ldc_alloc(vio->vdev->channel_id, &cfg, event_arg);
+	if (IS_ERR(lp))
+		return PTR_ERR(lp);
+
+	vio->lp = lp;
+
+	return 0;
+}
+EXPORT_SYMBOL(vio_ldc_alloc);
+
+void vio_ldc_free(struct vio_driver_state *vio)
+{
+	ldc_free(vio->lp);
+	vio->lp = NULL;
+
+	kfree(vio->desc_buf);
+	vio->desc_buf = NULL;
+	vio->desc_buf_len = 0;
+}
+EXPORT_SYMBOL(vio_ldc_free);
+
+void vio_port_up(struct vio_driver_state *vio)
+{
+	unsigned long flags;
+	int err, state;
+
+	spin_lock_irqsave(&vio->lock, flags);
+
+	state = ldc_state(vio->lp);
+
+	err = 0;
+	if (state == LDC_STATE_INIT) {
+		err = ldc_bind(vio->lp, vio->name);
+		if (err)
+			printk(KERN_WARNING "%s: Port %lu bind failed, "
+			       "err=%d\n",
+			       vio->name, vio->vdev->channel_id, err);
+	}
+
+	if (!err) {
+		err = ldc_connect(vio->lp);
+		if (err)
+			printk(KERN_WARNING "%s: Port %lu connect failed, "
+			       "err=%d\n",
+			       vio->name, vio->vdev->channel_id, err);
+	}
+	if (err) {
+		unsigned long expires = jiffies + HZ;
+
+		expires = round_jiffies(expires);
+		mod_timer(&vio->timer, expires);
+	}
+
+	spin_unlock_irqrestore(&vio->lock, flags);
+}
+EXPORT_SYMBOL(vio_port_up);
+
+static void vio_port_timer(unsigned long _arg)
+{
+	struct vio_driver_state *vio = (struct vio_driver_state *) _arg;
+
+	vio_port_up(vio);
+}
+
+int vio_driver_init(struct vio_driver_state *vio, struct vio_dev *vdev,
+		    u8 dev_class, struct vio_version *ver_table,
+		    int ver_table_size, struct vio_driver_ops *ops,
+		    char *name)
+{
+	switch (dev_class) {
+	case VDEV_NETWORK:
+	case VDEV_NETWORK_SWITCH:
+	case VDEV_DISK:
+	case VDEV_DISK_SERVER:
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	if (!ops->send_attr ||
+	    !ops->handle_attr ||
+	    !ops->handshake_complete)
+		return -EINVAL;
+
+	if (!ver_table || ver_table_size < 0)
+		return -EINVAL;
+
+	if (!name)
+		return -EINVAL;
+
+	spin_lock_init(&vio->lock);
+
+	vio->name = name;
+
+	vio->dev_class = dev_class;
+	vio->vdev = vdev;
+
+	vio->ver_table = ver_table;
+	vio->ver_table_entries = ver_table_size;
+
+	vio->ops = ops;
+
+	setup_timer(&vio->timer, vio_port_timer, (unsigned long) vio);
+
+	return 0;
+}
+EXPORT_SYMBOL(vio_driver_init);