blob: 635d67ffc9a39f72f3acd24f94b052e754fcfcb1 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/* viohs.c: LDOM Virtual I/O handshake helper layer.
*
* Copyright (C) 2007 David S. Miller <davem@davemloft.net>
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/sched/clock.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;
}
static void flush_rx_dring(struct vio_driver_state *vio)
{
struct vio_dring_state *dr;
u64 ident;
BUG_ON(!(vio->dr_state & VIO_DR_STATE_RXREG));
dr = &vio->drings[VIO_DRIVER_RX_RING];
ident = dr->ident;
BUG_ON(!vio->desc_buf);
kfree(vio->desc_buf);
vio->desc_buf = NULL;
memset(dr, 0, sizeof(*dr));
dr->ident = ident;
}
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);
} else if (event == LDC_EVENT_RESET) {
vio->hs_state = VIO_HS_INVALID;
if (vio->dr_state & VIO_DR_STATE_RXREG)
flush_rx_dring(vio);
vio->dr_state = 0x00;
memset(&vio->ver, 0, sizeof(vio->ver));
ldc_disconnect(vio->lp);
}
}
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)
{
if (!vio->ops)
return -EINVAL;
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;
pkt->dev_class = vio->dev_class;
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)
return handshake_failure(vio);
nver = find_by_major(vio, pkt->major);
if (!nver)
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);
if (!vio->ops)
return 0;
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;
/* v1.6 and higher, ACK with desired, supported mode, or NACK */
if (vio_version_after_eq(vio, 1, 6)) {
if (!(pkt->options & VIO_TX_DRING))
goto send_nack;
pkt->options = VIO_TX_DRING;
}
BUG_ON(vio->desc_buf);
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] "
"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);
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)) {
if (vio->ops)
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);
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, vio->name);
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);
if (err)
printk(KERN_WARNING "%s: Port %lu bind failed, "
"err=%d\n",
vio->name, vio->vdev->channel_id, err);
}
if (!err) {
if (ldc_mode(vio->lp) == LDC_MODE_RAW)
ldc_set_state(vio->lp, LDC_STATE_CONNECTED);
else
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(struct timer_list *t)
{
struct vio_driver_state *vio = from_timer(vio, t, timer);
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:
case VDEV_CONSOLE_CON:
break;
default:
return -EINVAL;
}
if (dev_class == VDEV_NETWORK ||
dev_class == VDEV_NETWORK_SWITCH ||
dev_class == VDEV_DISK ||
dev_class == VDEV_DISK_SERVER) {
if (!ops || !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;
timer_setup(&vio->timer, vio_port_timer, 0);
return 0;
}
EXPORT_SYMBOL(vio_driver_init);