--- /dev/null
+/* ldc.c: Logical Domain Channel link-layer protocol driver.
+ *
+ * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/scatterlist.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/init.h>
+
+#include <asm/hypervisor.h>
+#include <asm/iommu.h>
+#include <asm/page.h>
+#include <asm/ldc.h>
+#include <asm/mdesc.h>
+
+#define DRV_MODULE_NAME "ldc"
+#define PFX DRV_MODULE_NAME ": "
+#define DRV_MODULE_VERSION "1.0"
+#define DRV_MODULE_RELDATE "June 25, 2007"
+
+static char version[] __devinitdata =
+ DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
+#define LDC_PACKET_SIZE 64
+
+/* Packet header layout for unreliable and reliable mode frames.
+ * When in RAW mode, packets are simply straight 64-byte payloads
+ * with no headers.
+ */
+struct ldc_packet {
+ u8 type;
+#define LDC_CTRL 0x01
+#define LDC_DATA 0x02
+#define LDC_ERR 0x10
+
+ u8 stype;
+#define LDC_INFO 0x01
+#define LDC_ACK 0x02
+#define LDC_NACK 0x04
+
+ u8 ctrl;
+#define LDC_VERS 0x01 /* Link Version */
+#define LDC_RTS 0x02 /* Request To Send */
+#define LDC_RTR 0x03 /* Ready To Receive */
+#define LDC_RDX 0x04 /* Ready for Data eXchange */
+#define LDC_CTRL_MSK 0x0f
+
+ u8 env;
+#define LDC_LEN 0x3f
+#define LDC_FRAG_MASK 0xc0
+#define LDC_START 0x40
+#define LDC_STOP 0x80
+
+ u32 seqid;
+
+ union {
+ u8 u_data[LDC_PACKET_SIZE - 8];
+ struct {
+ u32 pad;
+ u32 ackid;
+ u8 r_data[LDC_PACKET_SIZE - 8 - 8];
+ } r;
+ } u;
+};
+
+struct ldc_version {
+ u16 major;
+ u16 minor;
+};
+
+/* Ordered from largest major to lowest. */
+static struct ldc_version ver_arr[] = {
+ { .major = 1, .minor = 0 },
+};
+
+#define LDC_DEFAULT_MTU (4 * LDC_PACKET_SIZE)
+#define LDC_DEFAULT_NUM_ENTRIES (PAGE_SIZE / LDC_PACKET_SIZE)
+
+struct ldc_channel;
+
+struct ldc_mode_ops {
+ int (*write)(struct ldc_channel *, const void *, unsigned int);
+ int (*read)(struct ldc_channel *, void *, unsigned int);
+};
+
+static const struct ldc_mode_ops raw_ops;
+static const struct ldc_mode_ops nonraw_ops;
+static const struct ldc_mode_ops stream_ops;
+
+int ldom_domaining_enabled;
+
+struct ldc_iommu {
+ /* Protects arena alloc/free. */
+ spinlock_t lock;
+ struct iommu_arena arena;
+ struct ldc_mtable_entry *page_table;
+};
+
+struct ldc_channel {
+ /* Protects all operations that depend upon channel state. */
+ spinlock_t lock;
+
+ unsigned long id;
+
+ u8 *mssbuf;
+ u32 mssbuf_len;
+ u32 mssbuf_off;
+
+ struct ldc_packet *tx_base;
+ unsigned long tx_head;
+ unsigned long tx_tail;
+ unsigned long tx_num_entries;
+ unsigned long tx_ra;
+
+ unsigned long tx_acked;
+
+ struct ldc_packet *rx_base;
+ unsigned long rx_head;
+ unsigned long rx_tail;
+ unsigned long rx_num_entries;
+ unsigned long rx_ra;
+
+ u32 rcv_nxt;
+ u32 snd_nxt;
+
+ unsigned long chan_state;
+
+ struct ldc_channel_config cfg;
+ void *event_arg;
+
+ const struct ldc_mode_ops *mops;
+
+ struct ldc_iommu iommu;
+
+ struct ldc_version ver;
+
+ u8 hs_state;
+#define LDC_HS_CLOSED 0x00
+#define LDC_HS_OPEN 0x01
+#define LDC_HS_GOTVERS 0x02
+#define LDC_HS_SENTRTR 0x03
+#define LDC_HS_GOTRTR 0x04
+#define LDC_HS_COMPLETE 0x10
+
+ u8 flags;
+#define LDC_FLAG_ALLOCED_QUEUES 0x01
+#define LDC_FLAG_REGISTERED_QUEUES 0x02
+#define LDC_FLAG_REGISTERED_IRQS 0x04
+#define LDC_FLAG_RESET 0x10
+
+ u8 mss;
+ u8 state;
+
+ struct hlist_head mh_list;
+
+ struct hlist_node list;
+};
+
+#define ldcdbg(TYPE, f, a...) \
+do { if (lp->cfg.debug & LDC_DEBUG_##TYPE) \
+ printk(KERN_INFO PFX "ID[%lu] " f, lp->id, ## a); \
+} while (0)
+
+static const char *state_to_str(u8 state)
+{
+ switch (state) {
+ case LDC_STATE_INVALID:
+ return "INVALID";
+ case LDC_STATE_INIT:
+ return "INIT";
+ case LDC_STATE_BOUND:
+ return "BOUND";
+ case LDC_STATE_READY:
+ return "READY";
+ case LDC_STATE_CONNECTED:
+ return "CONNECTED";
+ default:
+ return "<UNKNOWN>";
+ }
+}
+
+static void ldc_set_state(struct ldc_channel *lp, u8 state)
+{
+ ldcdbg(STATE, "STATE (%s) --> (%s)\n",
+ state_to_str(lp->state),
+ state_to_str(state));
+
+ lp->state = state;
+}
+
+static unsigned long __advance(unsigned long off, unsigned long num_entries)
+{
+ off += LDC_PACKET_SIZE;
+ if (off == (num_entries * LDC_PACKET_SIZE))
+ off = 0;
+
+ return off;
+}
+
+static unsigned long rx_advance(struct ldc_channel *lp, unsigned long off)
+{
+ return __advance(off, lp->rx_num_entries);
+}
+
+static unsigned long tx_advance(struct ldc_channel *lp, unsigned long off)
+{
+ return __advance(off, lp->tx_num_entries);
+}
+
+static struct ldc_packet *handshake_get_tx_packet(struct ldc_channel *lp,
+ unsigned long *new_tail)
+{
+ struct ldc_packet *p;
+ unsigned long t;
+
+ t = tx_advance(lp, lp->tx_tail);
+ if (t == lp->tx_head)
+ return NULL;
+
+ *new_tail = t;
+
+ p = lp->tx_base;
+ return p + (lp->tx_tail / LDC_PACKET_SIZE);
+}
+
+/* When we are in reliable or stream mode, have to track the next packet
+ * we haven't gotten an ACK for in the TX queue using tx_acked. We have
+ * to be careful not to stomp over the queue past that point. During
+ * the handshake, we don't have TX data packets pending in the queue
+ * and that's why handshake_get_tx_packet() need not be mindful of
+ * lp->tx_acked.
+ */
+static unsigned long head_for_data(struct ldc_channel *lp)
+{
+ if (lp->cfg.mode == LDC_MODE_RELIABLE ||
+ lp->cfg.mode == LDC_MODE_STREAM)
+ return lp->tx_acked;
+ return lp->tx_head;
+}
+
+static int tx_has_space_for(struct ldc_channel *lp, unsigned int size)
+{
+ unsigned long limit, tail, new_tail, diff;
+ unsigned int mss;
+
+ limit = head_for_data(lp);
+ tail = lp->tx_tail;
+ new_tail = tx_advance(lp, tail);
+ if (new_tail == limit)
+ return 0;
+
+ if (limit > new_tail)
+ diff = limit - new_tail;
+ else
+ diff = (limit +
+ ((lp->tx_num_entries * LDC_PACKET_SIZE) - new_tail));
+ diff /= LDC_PACKET_SIZE;
+ mss = lp->mss;
+
+ if (diff * mss < size)
+ return 0;
+
+ return 1;
+}
+
+static struct ldc_packet *data_get_tx_packet(struct ldc_channel *lp,
+ unsigned long *new_tail)
+{
+ struct ldc_packet *p;
+ unsigned long h, t;
+
+ h = head_for_data(lp);
+ t = tx_advance(lp, lp->tx_tail);
+ if (t == h)
+ return NULL;
+
+ *new_tail = t;
+
+ p = lp->tx_base;
+ return p + (lp->tx_tail / LDC_PACKET_SIZE);
+}
+
+static int set_tx_tail(struct ldc_channel *lp, unsigned long tail)
+{
+ unsigned long orig_tail = lp->tx_tail;
+ int limit = 1000;
+
+ lp->tx_tail = tail;
+ while (limit-- > 0) {
+ unsigned long err;
+
+ err = sun4v_ldc_tx_set_qtail(lp->id, tail);
+ if (!err)
+ return 0;
+
+ if (err != HV_EWOULDBLOCK) {
+ lp->tx_tail = orig_tail;
+ return -EINVAL;
+ }
+ udelay(1);
+ }
+
+ lp->tx_tail = orig_tail;
+ return -EBUSY;
+}
+
+/* This just updates the head value in the hypervisor using
+ * a polling loop with a timeout. The caller takes care of
+ * upating software state representing the head change, if any.
+ */
+static int __set_rx_head(struct ldc_channel *lp, unsigned long head)
+{
+ int limit = 1000;
+
+ while (limit-- > 0) {
+ unsigned long err;
+
+ err = sun4v_ldc_rx_set_qhead(lp->id, head);
+ if (!err)
+ return 0;
+
+ if (err != HV_EWOULDBLOCK)
+ return -EINVAL;
+
+ udelay(1);
+ }
+
+ return -EBUSY;
+}
+
+static int send_tx_packet(struct ldc_channel *lp,
+ struct ldc_packet *p,
+ unsigned long new_tail)
+{
+ BUG_ON(p != (lp->tx_base + (lp->tx_tail / LDC_PACKET_SIZE)));
+
+ return set_tx_tail(lp, new_tail);
+}
+
+static struct ldc_packet *handshake_compose_ctrl(struct ldc_channel *lp,
+ u8 stype, u8 ctrl,
+ void *data, int dlen,
+ unsigned long *new_tail)
+{
+ struct ldc_packet *p = handshake_get_tx_packet(lp, new_tail);
+
+ if (p) {
+ memset(p, 0, sizeof(*p));
+ p->type = LDC_CTRL;
+ p->stype = stype;
+ p->ctrl = ctrl;
+ if (data)
+ memcpy(p->u.u_data, data, dlen);
+ }
+ return p;
+}
+
+static int start_handshake(struct ldc_channel *lp)
+{
+ struct ldc_packet *p;
+ struct ldc_version *ver;
+ unsigned long new_tail;
+
+ ver = &ver_arr[0];
+
+ ldcdbg(HS, "SEND VER INFO maj[%u] min[%u]\n",
+ ver->major, ver->minor);
+
+ p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
+ ver, sizeof(*ver), &new_tail);
+ if (p) {
+ int err = send_tx_packet(lp, p, new_tail);
+ if (!err)
+ lp->flags &= ~LDC_FLAG_RESET;
+ return err;
+ }
+ return -EBUSY;
+}
+
+static int send_version_nack(struct ldc_channel *lp,
+ u16 major, u16 minor)
+{
+ struct ldc_packet *p;
+ struct ldc_version ver;
+ unsigned long new_tail;
+
+ ver.major = major;
+ ver.minor = minor;
+
+ p = handshake_compose_ctrl(lp, LDC_NACK, LDC_VERS,
+ &ver, sizeof(ver), &new_tail);
+ if (p) {
+ ldcdbg(HS, "SEND VER NACK maj[%u] min[%u]\n",
+ ver.major, ver.minor);
+
+ return send_tx_packet(lp, p, new_tail);
+ }
+ return -EBUSY;
+}
+
+static int send_version_ack(struct ldc_channel *lp,
+ struct ldc_version *vp)
+{
+ struct ldc_packet *p;
+ unsigned long new_tail;
+
+ p = handshake_compose_ctrl(lp, LDC_ACK, LDC_VERS,
+ vp, sizeof(*vp), &new_tail);
+ if (p) {
+ ldcdbg(HS, "SEND VER ACK maj[%u] min[%u]\n",
+ vp->major, vp->minor);
+
+ return send_tx_packet(lp, p, new_tail);
+ }
+ return -EBUSY;
+}
+
+static int send_rts(struct ldc_channel *lp)
+{
+ struct ldc_packet *p;
+ unsigned long new_tail;
+
+ p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTS, NULL, 0,
+ &new_tail);
+ if (p) {
+ p->env = lp->cfg.mode;
+ p->seqid = 0;
+ lp->rcv_nxt = 0;
+
+ ldcdbg(HS, "SEND RTS env[0x%x] seqid[0x%x]\n",
+ p->env, p->seqid);
+
+ return send_tx_packet(lp, p, new_tail);
+ }
+ return -EBUSY;
+}
+
+static int send_rtr(struct ldc_channel *lp)
+{
+ struct ldc_packet *p;
+ unsigned long new_tail;
+
+ p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTR, NULL, 0,
+ &new_tail);
+ if (p) {
+ p->env = lp->cfg.mode;
+ p->seqid = 0;
+
+ ldcdbg(HS, "SEND RTR env[0x%x] seqid[0x%x]\n",
+ p->env, p->seqid);
+
+ return send_tx_packet(lp, p, new_tail);
+ }
+ return -EBUSY;
+}
+
+static int send_rdx(struct ldc_channel *lp)
+{
+ struct ldc_packet *p;
+ unsigned long new_tail;
+
+ p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RDX, NULL, 0,
+ &new_tail);
+ if (p) {
+ p->env = 0;
+ p->seqid = ++lp->snd_nxt;
+ p->u.r.ackid = lp->rcv_nxt;
+
+ ldcdbg(HS, "SEND RDX env[0x%x] seqid[0x%x] ackid[0x%x]\n",
+ p->env, p->seqid, p->u.r.ackid);
+
+ return send_tx_packet(lp, p, new_tail);
+ }
+ return -EBUSY;
+}
+
+static int send_data_nack(struct ldc_channel *lp, struct ldc_packet *data_pkt)
+{
+ struct ldc_packet *p;
+ unsigned long new_tail;
+ int err;
+
+ p = data_get_tx_packet(lp, &new_tail);
+ if (!p)
+ return -EBUSY;
+ memset(p, 0, sizeof(*p));
+ p->type = data_pkt->type;
+ p->stype = LDC_NACK;
+ p->ctrl = data_pkt->ctrl & LDC_CTRL_MSK;
+ p->seqid = lp->snd_nxt;
+ p->u.r.ackid = lp->rcv_nxt;
+
+ ldcdbg(HS, "SEND DATA NACK type[0x%x] ctl[0x%x] seq[0x%x] ack[0x%x]\n",
+ p->type, p->ctrl, p->seqid, p->u.r.ackid);
+
+ err = send_tx_packet(lp, p, new_tail);
+ if (!err)
+ lp->snd_nxt++;
+
+ return err;
+}
+
+static int ldc_abort(struct ldc_channel *lp)
+{
+ unsigned long hv_err;
+
+ ldcdbg(STATE, "ABORT\n");
+
+ /* We report but do not act upon the hypervisor errors because
+ * there really isn't much we can do if they fail at this point.
+ */
+ hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
+ if (hv_err)
+ printk(KERN_ERR PFX "ldc_abort: "
+ "sun4v_ldc_tx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
+ lp->id, lp->tx_ra, lp->tx_num_entries, hv_err);
+
+ hv_err = sun4v_ldc_tx_get_state(lp->id,
+ &lp->tx_head,
+ &lp->tx_tail,
+ &lp->chan_state);
+ if (hv_err)
+ printk(KERN_ERR PFX "ldc_abort: "
+ "sun4v_ldc_tx_get_state(%lx,...) failed, err=%lu\n",
+ lp->id, hv_err);
+
+ hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
+ if (hv_err)
+ printk(KERN_ERR PFX "ldc_abort: "
+ "sun4v_ldc_rx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
+ lp->id, lp->rx_ra, lp->rx_num_entries, hv_err);
+
+ /* Refetch the RX queue state as well, because we could be invoked
+ * here in the queue processing context.
+ */
+ hv_err = sun4v_ldc_rx_get_state(lp->id,
+ &lp->rx_head,
+ &lp->rx_tail,
+ &lp->chan_state);
+ if (hv_err)
+ printk(KERN_ERR PFX "ldc_abort: "
+ "sun4v_ldc_rx_get_state(%lx,...) failed, err=%lu\n",
+ lp->id, hv_err);
+
+ return -ECONNRESET;
+}
+
+static struct ldc_version *find_by_major(u16 major)
+{
+ struct ldc_version *ret = NULL;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ver_arr); i++) {
+ struct ldc_version *v = &ver_arr[i];
+ if (v->major <= major) {
+ ret = v;
+ break;
+ }
+ }
+ return ret;
+}
+
+static int process_ver_info(struct ldc_channel *lp, struct ldc_version *vp)
+{
+ struct ldc_version *vap;
+ int err;
+
+ ldcdbg(HS, "GOT VERSION INFO major[%x] minor[%x]\n",
+ vp->major, vp->minor);
+
+ if (lp->hs_state == LDC_HS_GOTVERS) {
+ lp->hs_state = LDC_HS_OPEN;
+ memset(&lp->ver, 0, sizeof(lp->ver));
+ }
+
+ vap = find_by_major(vp->major);
+ if (!vap) {
+ err = send_version_nack(lp, 0, 0);
+ } else if (vap->major != vp->major) {
+ err = send_version_nack(lp, vap->major, vap->minor);
+ } else {
+ struct ldc_version ver = *vp;
+ if (ver.minor > vap->minor)
+ ver.minor = vap->minor;
+ err = send_version_ack(lp, &ver);
+ if (!err) {
+ lp->ver = ver;
+ lp->hs_state = LDC_HS_GOTVERS;
+ }
+ }
+ if (err)
+ return ldc_abort(lp);
+
+ return 0;
+}
+
+static int process_ver_ack(struct ldc_channel *lp, struct ldc_version *vp)
+{
+ ldcdbg(HS, "GOT VERSION ACK major[%x] minor[%x]\n",
+ vp->major, vp->minor);
+
+ if (lp->hs_state == LDC_HS_GOTVERS) {
+ if (lp->ver.major != vp->major ||
+ lp->ver.minor != vp->minor)
+ return ldc_abort(lp);
+ } else {
+ lp->ver = *vp;
+ lp->hs_state = LDC_HS_GOTVERS;
+ }
+ if (send_rts(lp))
+ return ldc_abort(lp);
+ return 0;
+}
+
+static int process_ver_nack(struct ldc_channel *lp, struct ldc_version *vp)
+{
+ struct ldc_version *vap;
+
+ if ((vp->major == 0 && vp->minor == 0) ||
+ !(vap = find_by_major(vp->major))) {
+ return ldc_abort(lp);
+ } else {
+ struct ldc_packet *p;
+ unsigned long new_tail;
+
+ p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
+ vap, sizeof(*vap),
+ &new_tail);
+ if (p)
+ return send_tx_packet(lp, p, new_tail);
+ else
+ return ldc_abort(lp);
+ }
+}
+
+static int process_version(struct ldc_channel *lp,
+ struct ldc_packet *p)
+{
+ struct ldc_version *vp;
+
+ vp = (struct ldc_version *) p->u.u_data;
+
+ switch (p->stype) {
+ case LDC_INFO:
+ return process_ver_info(lp, vp);
+
+ case LDC_ACK:
+ return process_ver_ack(lp, vp);
+
+ case LDC_NACK:
+ return process_ver_nack(lp, vp);
+
+ default:
+ return ldc_abort(lp);
+ }
+}
+
+static int process_rts(struct ldc_channel *lp,
+ struct ldc_packet *p)
+{
+ ldcdbg(HS, "GOT RTS stype[%x] seqid[%x] env[%x]\n",
+ p->stype, p->seqid, p->env);
+
+ if (p->stype != LDC_INFO ||
+ lp->hs_state != LDC_HS_GOTVERS ||
+ p->env != lp->cfg.mode)
+ return ldc_abort(lp);
+
+ lp->snd_nxt = p->seqid;
+ lp->rcv_nxt = p->seqid;
+ lp->hs_state = LDC_HS_SENTRTR;
+ if (send_rtr(lp))
+ return ldc_abort(lp);
+
+ return 0;
+}
+
+static int process_rtr(struct ldc_channel *lp,
+ struct ldc_packet *p)
+{
+ ldcdbg(HS, "GOT RTR stype[%x] seqid[%x] env[%x]\n",
+ p->stype, p->seqid, p->env);
+
+ if (p->stype != LDC_INFO ||
+ p->env != lp->cfg.mode)
+ return ldc_abort(lp);
+
+ lp->snd_nxt = p->seqid;
+ lp->hs_state = LDC_HS_COMPLETE;
+ ldc_set_state(lp, LDC_STATE_CONNECTED);
+ send_rdx(lp);
+
+ return LDC_EVENT_UP;
+}
+
+static int rx_seq_ok(struct ldc_channel *lp, u32 seqid)
+{
+ return lp->rcv_nxt + 1 == seqid;
+}
+
+static int process_rdx(struct ldc_channel *lp,
+ struct ldc_packet *p)
+{
+ ldcdbg(HS, "GOT RDX stype[%x] seqid[%x] env[%x] ackid[%x]\n",
+ p->stype, p->seqid, p->env, p->u.r.ackid);
+
+ if (p->stype != LDC_INFO ||
+ !(rx_seq_ok(lp, p->seqid)))
+ return ldc_abort(lp);
+
+ lp->rcv_nxt = p->seqid;
+
+ lp->hs_state = LDC_HS_COMPLETE;
+ ldc_set_state(lp, LDC_STATE_CONNECTED);
+
+ return LDC_EVENT_UP;
+}
+
+static int process_control_frame(struct ldc_channel *lp,
+ struct ldc_packet *p)
+{
+ switch (p->ctrl) {
+ case LDC_VERS:
+ return process_version(lp, p);
+
+ case LDC_RTS:
+ return process_rts(lp, p);
+
+ case LDC_RTR:
+ return process_rtr(lp, p);
+
+ case LDC_RDX:
+ return process_rdx(lp, p);
+
+ default:
+ return ldc_abort(lp);
+ }
+}
+
+static int process_error_frame(struct ldc_channel *lp,
+ struct ldc_packet *p)
+{
+ return ldc_abort(lp);
+}
+
+static int process_data_ack(struct ldc_channel *lp,
+ struct ldc_packet *ack)
+{
+ unsigned long head = lp->tx_acked;
+ u32 ackid = ack->u.r.ackid;
+
+ while (1) {
+ struct ldc_packet *p = lp->tx_base + (head / LDC_PACKET_SIZE);
+
+ head = tx_advance(lp, head);
+
+ if (p->seqid == ackid) {
+ lp->tx_acked = head;
+ return 0;
+ }
+ if (head == lp->tx_head)
+ return ldc_abort(lp);
+ }
+
+ return 0;
+}
+
+static void send_events(struct ldc_channel *lp, unsigned int event_mask)
+{
+ if (event_mask & LDC_EVENT_RESET)
+ lp->cfg.event(lp->event_arg, LDC_EVENT_RESET);
+ if (event_mask & LDC_EVENT_UP)
+ lp->cfg.event(lp->event_arg, LDC_EVENT_UP);
+ if (event_mask & LDC_EVENT_DATA_READY)
+ lp->cfg.event(lp->event_arg, LDC_EVENT_DATA_READY);
+}
+
+static irqreturn_t ldc_rx(int irq, void *dev_id)
+{
+ struct ldc_channel *lp = dev_id;
+ unsigned long orig_state, hv_err, flags;
+ unsigned int event_mask;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ orig_state = lp->chan_state;
+ hv_err = sun4v_ldc_rx_get_state(lp->id,
+ &lp->rx_head,
+ &lp->rx_tail,
+ &lp->chan_state);
+
+ ldcdbg(RX, "RX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
+ orig_state, lp->chan_state, lp->rx_head, lp->rx_tail);
+
+ event_mask = 0;
+
+ if (lp->cfg.mode == LDC_MODE_RAW &&
+ lp->chan_state == LDC_CHANNEL_UP) {
+ lp->hs_state = LDC_HS_COMPLETE;
+ ldc_set_state(lp, LDC_STATE_CONNECTED);
+
+ event_mask |= LDC_EVENT_UP;
+
+ orig_state = lp->chan_state;
+ }
+
+ /* If we are in reset state, flush the RX queue and ignore
+ * everything.
+ */
+ if (lp->flags & LDC_FLAG_RESET) {
+ (void) __set_rx_head(lp, lp->rx_tail);
+ goto out;
+ }
+
+ /* Once we finish the handshake, we let the ldc_read()
+ * paths do all of the control frame and state management.
+ * Just trigger the callback.
+ */
+ if (lp->hs_state == LDC_HS_COMPLETE) {
+handshake_complete:
+ if (lp->chan_state != orig_state) {
+ unsigned int event = LDC_EVENT_RESET;
+
+ if (lp->chan_state == LDC_CHANNEL_UP)
+ event = LDC_EVENT_UP;
+
+ event_mask |= event;
+ }
+ if (lp->rx_head != lp->rx_tail)
+ event_mask |= LDC_EVENT_DATA_READY;
+
+ goto out;
+ }
+
+ if (lp->chan_state != orig_state)
+ goto out;
+
+ while (lp->rx_head != lp->rx_tail) {
+ struct ldc_packet *p;
+ unsigned long new;
+ int err;
+
+ p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
+
+ switch (p->type) {
+ case LDC_CTRL:
+ err = process_control_frame(lp, p);
+ if (err > 0)
+ event_mask |= err;
+ break;
+
+ case LDC_DATA:
+ event_mask |= LDC_EVENT_DATA_READY;
+ err = 0;
+ break;
+
+ case LDC_ERR:
+ err = process_error_frame(lp, p);
+ break;
+
+ default:
+ err = ldc_abort(lp);
+ break;
+ }
+
+ if (err < 0)
+ break;
+
+ new = lp->rx_head;
+ new += LDC_PACKET_SIZE;
+ if (new == (lp->rx_num_entries * LDC_PACKET_SIZE))
+ new = 0;
+ lp->rx_head = new;
+
+ err = __set_rx_head(lp, new);
+ if (err < 0) {
+ (void) ldc_abort(lp);
+ break;
+ }
+ if (lp->hs_state == LDC_HS_COMPLETE)
+ goto handshake_complete;
+ }
+
+out:
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ send_events(lp, event_mask);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ldc_tx(int irq, void *dev_id)
+{
+ struct ldc_channel *lp = dev_id;
+ unsigned long flags, hv_err, orig_state;
+ unsigned int event_mask = 0;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ orig_state = lp->chan_state;
+ hv_err = sun4v_ldc_tx_get_state(lp->id,
+ &lp->tx_head,
+ &lp->tx_tail,
+ &lp->chan_state);
+
+ ldcdbg(TX, " TX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
+ orig_state, lp->chan_state, lp->tx_head, lp->tx_tail);
+
+ if (lp->cfg.mode == LDC_MODE_RAW &&
+ lp->chan_state == LDC_CHANNEL_UP) {
+ lp->hs_state = LDC_HS_COMPLETE;
+ ldc_set_state(lp, LDC_STATE_CONNECTED);
+
+ event_mask |= LDC_EVENT_UP;
+ }
+
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ send_events(lp, event_mask);
+
+ return IRQ_HANDLED;
+}
+
+/* XXX ldc_alloc() and ldc_free() needs to run under a mutex so
+ * XXX that addition and removal from the ldc_channel_list has
+ * XXX atomicity, otherwise the __ldc_channel_exists() check is
+ * XXX totally pointless as another thread can slip into ldc_alloc()
+ * XXX and add a channel with the same ID. There also needs to be
+ * XXX a spinlock for ldc_channel_list.
+ */
+static HLIST_HEAD(ldc_channel_list);
+
+static int __ldc_channel_exists(unsigned long id)
+{
+ struct ldc_channel *lp;
+ struct hlist_node *n;
+
+ hlist_for_each_entry(lp, n, &ldc_channel_list, list) {
+ if (lp->id == id)
+ return 1;
+ }
+ return 0;
+}
+
+static int alloc_queue(const char *name, unsigned long num_entries,
+ struct ldc_packet **base, unsigned long *ra)
+{
+ unsigned long size, order;
+ void *q;
+
+ size = num_entries * LDC_PACKET_SIZE;
+ order = get_order(size);
+
+ q = (void *) __get_free_pages(GFP_KERNEL, order);
+ if (!q) {
+ printk(KERN_ERR PFX "Alloc of %s queue failed with "
+ "size=%lu order=%lu\n", name, size, order);
+ return -ENOMEM;
+ }
+
+ memset(q, 0, PAGE_SIZE << order);
+
+ *base = q;
+ *ra = __pa(q);
+
+ return 0;
+}
+
+static void free_queue(unsigned long num_entries, struct ldc_packet *q)
+{
+ unsigned long size, order;
+
+ if (!q)
+ return;
+
+ size = num_entries * LDC_PACKET_SIZE;
+ order = get_order(size);
+
+ free_pages((unsigned long)q, order);
+}
+
+/* XXX Make this configurable... XXX */
+#define LDC_IOTABLE_SIZE (8 * 1024)
+
+static int ldc_iommu_init(struct ldc_channel *lp)
+{
+ unsigned long sz, num_tsb_entries, tsbsize, order;
+ struct ldc_iommu *iommu = &lp->iommu;
+ struct ldc_mtable_entry *table;
+ unsigned long hv_err;
+ int err;
+
+ num_tsb_entries = LDC_IOTABLE_SIZE;
+ tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
+
+ spin_lock_init(&iommu->lock);
+
+ sz = num_tsb_entries / 8;
+ sz = (sz + 7UL) & ~7UL;
+ iommu->arena.map = kzalloc(sz, GFP_KERNEL);
+ if (!iommu->arena.map) {
+ printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz);
+ return -ENOMEM;
+ }
+
+ iommu->arena.limit = num_tsb_entries;
+
+ order = get_order(tsbsize);
+
+ table = (struct ldc_mtable_entry *)
+ __get_free_pages(GFP_KERNEL, order);
+ err = -ENOMEM;
+ if (!table) {
+ printk(KERN_ERR PFX "Alloc of MTE table failed, "
+ "size=%lu order=%lu\n", tsbsize, order);
+ goto out_free_map;
+ }
+
+ memset(table, 0, PAGE_SIZE << order);
+
+ iommu->page_table = table;
+
+ hv_err = sun4v_ldc_set_map_table(lp->id, __pa(table),
+ num_tsb_entries);
+ err = -EINVAL;
+ if (hv_err)
+ goto out_free_table;
+
+ return 0;
+
+out_free_table:
+ free_pages((unsigned long) table, order);
+ iommu->page_table = NULL;
+
+out_free_map:
+ kfree(iommu->arena.map);
+ iommu->arena.map = NULL;
+
+ return err;
+}
+
+static void ldc_iommu_release(struct ldc_channel *lp)
+{
+ struct ldc_iommu *iommu = &lp->iommu;
+ unsigned long num_tsb_entries, tsbsize, order;
+
+ (void) sun4v_ldc_set_map_table(lp->id, 0, 0);
+
+ num_tsb_entries = iommu->arena.limit;
+ tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
+ order = get_order(tsbsize);
+
+ free_pages((unsigned long) iommu->page_table, order);
+ iommu->page_table = NULL;
+
+ kfree(iommu->arena.map);
+ iommu->arena.map = NULL;
+}
+
+struct ldc_channel *ldc_alloc(unsigned long id,
+ const struct ldc_channel_config *cfgp,
+ void *event_arg)
+{
+ struct ldc_channel *lp;
+ const struct ldc_mode_ops *mops;
+ unsigned long dummy1, dummy2, hv_err;
+ u8 mss, *mssbuf;
+ int err;
+
+ err = -ENODEV;
+ if (!ldom_domaining_enabled)
+ goto out_err;
+
+ err = -EINVAL;
+ if (!cfgp)
+ goto out_err;
+
+ switch (cfgp->mode) {
+ case LDC_MODE_RAW:
+ mops = &raw_ops;
+ mss = LDC_PACKET_SIZE;
+ break;
+
+ case LDC_MODE_UNRELIABLE:
+ mops = &nonraw_ops;
+ mss = LDC_PACKET_SIZE - 8;
+ break;
+
+ case LDC_MODE_RELIABLE:
+ mops = &nonraw_ops;
+ mss = LDC_PACKET_SIZE - 8 - 8;
+ break;
+
+ case LDC_MODE_STREAM:
+ mops = &stream_ops;
+ mss = LDC_PACKET_SIZE - 8 - 8;
+ break;
+
+ default:
+ goto out_err;
+ }
+
+ if (!cfgp->event || !event_arg || !cfgp->rx_irq || !cfgp->tx_irq)
+ goto out_err;
+
+ hv_err = sun4v_ldc_tx_qinfo(id, &dummy1, &dummy2);
+ err = -ENODEV;
+ if (hv_err == HV_ECHANNEL)
+ goto out_err;
+
+ err = -EEXIST;
+ if (__ldc_channel_exists(id))
+ goto out_err;
+
+ mssbuf = NULL;
+
+ lp = kzalloc(sizeof(*lp), GFP_KERNEL);
+ err = -ENOMEM;
+ if (!lp)
+ goto out_err;
+
+ spin_lock_init(&lp->lock);
+
+ lp->id = id;
+
+ err = ldc_iommu_init(lp);
+ if (err)
+ goto out_free_ldc;
+
+ lp->mops = mops;
+ lp->mss = mss;
+
+ lp->cfg = *cfgp;
+ if (!lp->cfg.mtu)
+ lp->cfg.mtu = LDC_DEFAULT_MTU;
+
+ if (lp->cfg.mode == LDC_MODE_STREAM) {
+ mssbuf = kzalloc(lp->cfg.mtu, GFP_KERNEL);
+ if (!mssbuf) {
+ err = -ENOMEM;
+ goto out_free_iommu;
+ }
+ lp->mssbuf = mssbuf;
+ }
+
+ lp->event_arg = event_arg;
+
+ /* XXX allow setting via ldc_channel_config to override defaults
+ * XXX or use some formula based upon mtu
+ */
+ lp->tx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
+ lp->rx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
+
+ err = alloc_queue("TX", lp->tx_num_entries,
+ &lp->tx_base, &lp->tx_ra);
+ if (err)
+ goto out_free_mssbuf;
+
+ err = alloc_queue("RX", lp->rx_num_entries,
+ &lp->rx_base, &lp->rx_ra);
+ if (err)
+ goto out_free_txq;
+
+ lp->flags |= LDC_FLAG_ALLOCED_QUEUES;
+
+ lp->hs_state = LDC_HS_CLOSED;
+ ldc_set_state(lp, LDC_STATE_INIT);
+
+ INIT_HLIST_NODE(&lp->list);
+ hlist_add_head(&lp->list, &ldc_channel_list);
+
+ INIT_HLIST_HEAD(&lp->mh_list);
+
+ return lp;
+
+out_free_txq:
+ free_queue(lp->tx_num_entries, lp->tx_base);
+
+out_free_mssbuf:
+ if (mssbuf)
+ kfree(mssbuf);
+
+out_free_iommu:
+ ldc_iommu_release(lp);
+
+out_free_ldc:
+ kfree(lp);
+
+out_err:
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(ldc_alloc);
+
+void ldc_free(struct ldc_channel *lp)
+{
+ if (lp->flags & LDC_FLAG_REGISTERED_IRQS) {
+ free_irq(lp->cfg.rx_irq, lp);
+ free_irq(lp->cfg.tx_irq, lp);
+ }
+
+ if (lp->flags & LDC_FLAG_REGISTERED_QUEUES) {
+ sun4v_ldc_tx_qconf(lp->id, 0, 0);
+ sun4v_ldc_rx_qconf(lp->id, 0, 0);
+ lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
+ }
+ if (lp->flags & LDC_FLAG_ALLOCED_QUEUES) {
+ free_queue(lp->tx_num_entries, lp->tx_base);
+ free_queue(lp->rx_num_entries, lp->rx_base);
+ lp->flags &= ~LDC_FLAG_ALLOCED_QUEUES;
+ }
+
+ hlist_del(&lp->list);
+
+ if (lp->mssbuf)
+ kfree(lp->mssbuf);
+
+ ldc_iommu_release(lp);
+
+ kfree(lp);
+}
+EXPORT_SYMBOL(ldc_free);
+
+/* Bind the channel. This registers the LDC queues with
+ * the hypervisor and puts the channel into a pseudo-listening
+ * state. This does not initiate a handshake, ldc_connect() does
+ * that.
+ */
+int ldc_bind(struct ldc_channel *lp)
+{
+ unsigned long hv_err, flags;
+ int err = -EINVAL;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ if (lp->state != LDC_STATE_INIT)
+ goto out_err;
+
+ err = request_irq(lp->cfg.rx_irq, ldc_rx,
+ IRQF_SAMPLE_RANDOM | IRQF_SHARED,
+ "LDC RX", lp);
+ if (err)
+ goto out_err;
+
+ err = request_irq(lp->cfg.tx_irq, ldc_tx,
+ IRQF_SAMPLE_RANDOM | IRQF_SHARED,
+ "LDC TX", lp);
+ if (err)
+ goto out_free_rx_irq;
+
+
+ lp->flags |= LDC_FLAG_REGISTERED_IRQS;
+
+ err = -ENODEV;
+ hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
+ if (hv_err)
+ goto out_free_tx_irq;
+
+ hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
+ if (hv_err)
+ goto out_free_tx_irq;
+
+ hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
+ if (hv_err)
+ goto out_unmap_tx;
+
+ hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
+ if (hv_err)
+ goto out_unmap_tx;
+
+ lp->flags |= LDC_FLAG_REGISTERED_QUEUES;
+
+ hv_err = sun4v_ldc_tx_get_state(lp->id,
+ &lp->tx_head,
+ &lp->tx_tail,
+ &lp->chan_state);
+ err = -EBUSY;
+ if (hv_err)
+ goto out_unmap_rx;
+
+ lp->tx_acked = lp->tx_head;
+
+ lp->hs_state = LDC_HS_OPEN;
+ ldc_set_state(lp, LDC_STATE_BOUND);
+
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ return 0;
+
+out_unmap_rx:
+ lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
+ sun4v_ldc_rx_qconf(lp->id, 0, 0);
+
+out_unmap_tx:
+ sun4v_ldc_tx_qconf(lp->id, 0, 0);
+
+out_free_tx_irq:
+ lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
+ free_irq(lp->cfg.tx_irq, lp);
+
+out_free_rx_irq:
+ free_irq(lp->cfg.rx_irq, lp);
+
+out_err:
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ return err;
+}
+EXPORT_SYMBOL(ldc_bind);
+
+int ldc_connect(struct ldc_channel *lp)
+{
+ unsigned long flags;
+ int err;
+
+ if (lp->cfg.mode == LDC_MODE_RAW)
+ return -EINVAL;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
+ !(lp->flags & LDC_FLAG_REGISTERED_QUEUES) ||
+ lp->hs_state != LDC_HS_OPEN)
+ err = -EINVAL;
+ else
+ err = start_handshake(lp);
+
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ return err;
+}
+EXPORT_SYMBOL(ldc_connect);
+
+int ldc_disconnect(struct ldc_channel *lp)
+{
+ unsigned long hv_err, flags;
+ int err;
+
+ if (lp->cfg.mode == LDC_MODE_RAW)
+ return -EINVAL;
+
+ if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
+ !(lp->flags & LDC_FLAG_REGISTERED_QUEUES))
+ return -EINVAL;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ err = -ENODEV;
+ hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
+ if (hv_err)
+ goto out_err;
+
+ hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
+ if (hv_err)
+ goto out_err;
+
+ hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
+ if (hv_err)
+ goto out_err;
+
+ hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
+ if (hv_err)
+ goto out_err;
+
+ ldc_set_state(lp, LDC_STATE_BOUND);
+ lp->hs_state = LDC_HS_OPEN;
+ lp->flags |= LDC_FLAG_RESET;
+
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ return 0;
+
+out_err:
+ sun4v_ldc_tx_qconf(lp->id, 0, 0);
+ sun4v_ldc_rx_qconf(lp->id, 0, 0);
+ free_irq(lp->cfg.tx_irq, lp);
+ free_irq(lp->cfg.rx_irq, lp);
+ lp->flags &= ~(LDC_FLAG_REGISTERED_IRQS |
+ LDC_FLAG_REGISTERED_QUEUES);
+ ldc_set_state(lp, LDC_STATE_INIT);
+
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ return err;
+}
+EXPORT_SYMBOL(ldc_disconnect);
+
+int ldc_state(struct ldc_channel *lp)
+{
+ return lp->state;
+}
+EXPORT_SYMBOL(ldc_state);
+
+static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size)
+{
+ struct ldc_packet *p;
+ unsigned long new_tail;
+ int err;
+
+ if (size > LDC_PACKET_SIZE)
+ return -EMSGSIZE;
+
+ p = data_get_tx_packet(lp, &new_tail);
+ if (!p)
+ return -EAGAIN;
+
+ memcpy(p, buf, size);
+
+ err = send_tx_packet(lp, p, new_tail);
+ if (!err)
+ err = size;
+
+ return err;
+}
+
+static int read_raw(struct ldc_channel *lp, void *buf, unsigned int size)
+{
+ struct ldc_packet *p;
+ unsigned long hv_err, new;
+ int err;
+
+ if (size < LDC_PACKET_SIZE)
+ return -EINVAL;
+
+ hv_err = sun4v_ldc_rx_get_state(lp->id,
+ &lp->rx_head,
+ &lp->rx_tail,
+ &lp->chan_state);
+ if (hv_err)
+ return ldc_abort(lp);
+
+ if (lp->chan_state == LDC_CHANNEL_DOWN ||
+ lp->chan_state == LDC_CHANNEL_RESETTING)
+ return -ECONNRESET;
+
+ if (lp->rx_head == lp->rx_tail)
+ return 0;
+
+ p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
+ memcpy(buf, p, LDC_PACKET_SIZE);
+
+ new = rx_advance(lp, lp->rx_head);
+ lp->rx_head = new;
+
+ err = __set_rx_head(lp, new);
+ if (err < 0)
+ err = -ECONNRESET;
+ else
+ err = LDC_PACKET_SIZE;
+
+ return err;
+}
+
+static const struct ldc_mode_ops raw_ops = {
+ .write = write_raw,
+ .read = read_raw,
+};
+
+static int write_nonraw(struct ldc_channel *lp, const void *buf,
+ unsigned int size)
+{
+ unsigned long hv_err, tail;
+ unsigned int copied;
+ u32 seq;
+ int err;
+
+ hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail,
+ &lp->chan_state);
+ if (unlikely(hv_err))
+ return -EBUSY;
+
+ if (unlikely(lp->chan_state != LDC_CHANNEL_UP))
+ return ldc_abort(lp);
+
+ if (!tx_has_space_for(lp, size))
+ return -EAGAIN;
+
+ seq = lp->snd_nxt;
+ copied = 0;
+ tail = lp->tx_tail;
+ while (copied < size) {
+ struct ldc_packet *p = lp->tx_base + (tail / LDC_PACKET_SIZE);
+ u8 *data = ((lp->cfg.mode == LDC_MODE_UNRELIABLE) ?
+ p->u.u_data :
+ p->u.r.r_data);
+ int data_len;
+
+ p->type = LDC_DATA;
+ p->stype = LDC_INFO;
+ p->ctrl = 0;
+
+ data_len = size - copied;
+ if (data_len > lp->mss)
+ data_len = lp->mss;
+
+ BUG_ON(data_len > LDC_LEN);
+
+ p->env = (data_len |
+ (copied == 0 ? LDC_START : 0) |
+ (data_len == size - copied ? LDC_STOP : 0));
+
+ p->seqid = ++seq;
+
+ ldcdbg(DATA, "SENT DATA [%02x:%02x:%02x:%02x:%08x]\n",
+ p->type,
+ p->stype,
+ p->ctrl,
+ p->env,
+ p->seqid);
+
+ memcpy(data, buf, data_len);
+ buf += data_len;
+ copied += data_len;
+
+ tail = tx_advance(lp, tail);
+ }
+
+ err = set_tx_tail(lp, tail);
+ if (!err) {
+ lp->snd_nxt = seq;
+ err = size;
+ }
+
+ return err;
+}
+
+static int rx_bad_seq(struct ldc_channel *lp, struct ldc_packet *p,
+ struct ldc_packet *first_frag)
+{
+ int err;
+
+ if (first_frag)
+ lp->rcv_nxt = first_frag->seqid - 1;
+
+ err = send_data_nack(lp, p);
+ if (err)
+ return err;
+
+ err = __set_rx_head(lp, lp->rx_tail);
+ if (err < 0)
+ return ldc_abort(lp);
+
+ return 0;
+}
+
+static int data_ack_nack(struct ldc_channel *lp, struct ldc_packet *p)
+{
+ if (p->stype & LDC_ACK) {
+ int err = process_data_ack(lp, p);
+ if (err)
+ return err;
+ }
+ if (p->stype & LDC_NACK)
+ return ldc_abort(lp);
+
+ return 0;
+}
+
+static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head)
+{
+ unsigned long dummy;
+ int limit = 1000;
+
+ ldcdbg(DATA, "DATA WAIT cur_head[%lx] rx_head[%lx] rx_tail[%lx]\n",
+ cur_head, lp->rx_head, lp->rx_tail);
+ while (limit-- > 0) {
+ unsigned long hv_err;
+
+ hv_err = sun4v_ldc_rx_get_state(lp->id,
+ &dummy,
+ &lp->rx_tail,
+ &lp->chan_state);
+ if (hv_err)
+ return ldc_abort(lp);
+
+ ldcdbg(DATA, "REREAD head[%lx] tail[%lx] chan_state[%lx]\n",
+ dummy, lp->rx_tail, lp->chan_state);
+
+ if (lp->chan_state == LDC_CHANNEL_DOWN ||
+ lp->chan_state == LDC_CHANNEL_RESETTING)
+ return -ECONNRESET;
+
+ if (cur_head != lp->rx_tail) {
+ ldcdbg(DATA, "DATA WAIT DONE\n");
+ return 0;
+ }
+
+ udelay(1);
+ }
+ return -EAGAIN;
+}
+
+static int rx_set_head(struct ldc_channel *lp, unsigned long head)
+{
+ int err = __set_rx_head(lp, head);
+
+ if (err < 0)
+ return ldc_abort(lp);
+
+ lp->rx_head = head;
+ return 0;
+}
+
+static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
+{
+ struct ldc_packet *first_frag;
+ unsigned long hv_err, new;
+ int err, copied;
+
+ hv_err = sun4v_ldc_rx_get_state(lp->id,
+ &lp->rx_head,
+ &lp->rx_tail,
+ &lp->chan_state);
+ if (hv_err)
+ return ldc_abort(lp);
+
+ if (lp->chan_state == LDC_CHANNEL_DOWN ||
+ lp->chan_state == LDC_CHANNEL_RESETTING)
+ return -ECONNRESET;
+
+ if (lp->rx_head == lp->rx_tail)
+ return 0;
+
+ first_frag = NULL;
+ copied = err = 0;
+ new = lp->rx_head;
+ while (1) {
+ struct ldc_packet *p;
+ int pkt_len;
+
+ BUG_ON(new == lp->rx_tail);
+ p = lp->rx_base + (new / LDC_PACKET_SIZE);
+
+ ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x] "
+ "rcv_nxt[%08x]\n",
+ p->type,
+ p->stype,
+ p->ctrl,
+ p->env,
+ p->seqid,
+ lp->rcv_nxt);
+
+ if (unlikely(!rx_seq_ok(lp, p->seqid))) {
+ err = rx_bad_seq(lp, p, first_frag);
+ copied = 0;
+ break;
+ }
+
+ if (p->type & LDC_CTRL) {
+ err = process_control_frame(lp, p);
+ if (err < 0)
+ break;
+ err = 0;
+ }
+
+ lp->rcv_nxt = p->seqid;
+
+ if (!(p->type & LDC_DATA)) {
+ new = rx_advance(lp, new);
+ goto no_data;
+ }
+ if (p->stype & (LDC_ACK | LDC_NACK)) {
+ err = data_ack_nack(lp, p);
+ if (err)
+ break;
+ }
+ if (!(p->stype & LDC_INFO)) {
+ new = rx_advance(lp, new);
+ goto no_data;
+ }
+
+ pkt_len = p->env & LDC_LEN;
+
+ /* Every initial packet starts with the START bit set.
+ *
+ * Singleton packets will have both START+STOP set.
+ *
+ * Fragments will have START set in the first frame, STOP
+ * set in the last frame, and neither bit set in middle
+ * frames of the packet.
+ *
+ * Therefore if we are at the beginning of a packet and
+ * we don't see START, or we are in the middle of a fragmented
+ * packet and do see START, we are unsynchronized and should
+ * flush the RX queue.
+ */
+ if ((first_frag == NULL && !(p->env & LDC_START)) ||
+ (first_frag != NULL && (p->env & LDC_START))) {
+ if (!first_frag)
+ new = rx_advance(lp, new);
+
+ err = rx_set_head(lp, new);
+ if (err)
+ break;
+
+ if (!first_frag)
+ goto no_data;
+ }
+ if (!first_frag)
+ first_frag = p;
+
+ if (pkt_len > size - copied) {
+ /* User didn't give us a big enough buffer,
+ * what to do? This is a pretty serious error.
+ *
+ * Since we haven't updated the RX ring head to
+ * consume any of the packets, signal the error
+ * to the user and just leave the RX ring alone.
+ *
+ * This seems the best behavior because this allows
+ * a user of the LDC layer to start with a small
+ * RX buffer for ldc_read() calls and use -EMSGSIZE
+ * as a cue to enlarge it's read buffer.
+ */
+ err = -EMSGSIZE;
+ break;
+ }
+
+ /* Ok, we are gonna eat this one. */
+ new = rx_advance(lp, new);
+
+ memcpy(buf,
+ (lp->cfg.mode == LDC_MODE_UNRELIABLE ?
+ p->u.u_data : p->u.r.r_data), pkt_len);
+ buf += pkt_len;
+ copied += pkt_len;
+
+ if (p->env & LDC_STOP)
+ break;
+
+no_data:
+ if (new == lp->rx_tail) {
+ err = rx_data_wait(lp, new);
+ if (err)
+ break;
+ }
+ }
+
+ if (!err)
+ err = rx_set_head(lp, new);
+
+ if (err && first_frag)
+ lp->rcv_nxt = first_frag->seqid - 1;
+
+ if (!err)
+ err = copied;
+
+ return err;
+}
+
+static const struct ldc_mode_ops nonraw_ops = {
+ .write = write_nonraw,
+ .read = read_nonraw,
+};
+
+static int write_stream(struct ldc_channel *lp, const void *buf,
+ unsigned int size)
+{
+ if (size > lp->cfg.mtu)
+ size = lp->cfg.mtu;
+ return write_nonraw(lp, buf, size);
+}
+
+static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size)
+{
+ if (!lp->mssbuf_len) {
+ int err = read_nonraw(lp, lp->mssbuf,
+ (size > lp->cfg.mtu ?
+ lp->cfg.mtu : size));
+ if (err < 0)
+ return err;
+
+ lp->mssbuf_len = err;
+ lp->mssbuf_off = 0;
+ }
+
+ if (size > lp->mssbuf_len)
+ size = lp->mssbuf_len;
+ memcpy(buf, lp->mssbuf + lp->mssbuf_off, size);
+
+ lp->mssbuf_off += size;
+ lp->mssbuf_len -= size;
+
+ return size;
+}
+
+static const struct ldc_mode_ops stream_ops = {
+ .write = write_stream,
+ .read = read_stream,
+};
+
+int ldc_write(struct ldc_channel *lp, const void *buf, unsigned int size)
+{
+ unsigned long flags;
+ int err;
+
+ if (!buf)
+ return -EINVAL;
+
+ if (!size)
+ return 0;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ if (lp->hs_state != LDC_HS_COMPLETE)
+ err = -ENOTCONN;
+ else
+ err = lp->mops->write(lp, buf, size);
+
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ return err;
+}
+EXPORT_SYMBOL(ldc_write);
+
+int ldc_read(struct ldc_channel *lp, void *buf, unsigned int size)
+{
+ unsigned long flags;
+ int err;
+
+ if (!buf)
+ return -EINVAL;
+
+ if (!size)
+ return 0;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ if (lp->hs_state != LDC_HS_COMPLETE)
+ err = -ENOTCONN;
+ else
+ err = lp->mops->read(lp, buf, size);
+
+ spin_unlock_irqrestore(&lp->lock, flags);
+
+ return err;
+}
+EXPORT_SYMBOL(ldc_read);
+
+static long arena_alloc(struct ldc_iommu *iommu, unsigned long npages)
+{
+ struct iommu_arena *arena = &iommu->arena;
+ unsigned long n, i, start, end, limit;
+ int pass;
+
+ limit = arena->limit;
+ start = arena->hint;
+ pass = 0;
+
+again:
+ n = find_next_zero_bit(arena->map, limit, start);
+ end = n + npages;
+ if (unlikely(end >= limit)) {
+ if (likely(pass < 1)) {
+ limit = start;
+ start = 0;
+ pass++;
+ goto again;
+ } else {
+ /* Scanned the whole thing, give up. */
+ return -1;
+ }
+ }
+
+ for (i = n; i < end; i++) {
+ if (test_bit(i, arena->map)) {
+ start = i + 1;
+ goto again;
+ }
+ }
+
+ for (i = n; i < end; i++)
+ __set_bit(i, arena->map);
+
+ arena->hint = end;
+
+ return n;
+}
+
+#define COOKIE_PGSZ_CODE 0xf000000000000000ULL
+#define COOKIE_PGSZ_CODE_SHIFT 60ULL
+
+static u64 pagesize_code(void)
+{
+ switch (PAGE_SIZE) {
+ default:
+ case (8ULL * 1024ULL):
+ return 0;
+ case (64ULL * 1024ULL):
+ return 1;
+ case (512ULL * 1024ULL):
+ return 2;
+ case (4ULL * 1024ULL * 1024ULL):
+ return 3;
+ case (32ULL * 1024ULL * 1024ULL):
+ return 4;
+ case (256ULL * 1024ULL * 1024ULL):
+ return 5;
+ }
+}
+
+static u64 make_cookie(u64 index, u64 pgsz_code, u64 page_offset)
+{
+ return ((pgsz_code << COOKIE_PGSZ_CODE_SHIFT) |
+ (index << PAGE_SHIFT) |
+ page_offset);
+}
+
+static u64 cookie_to_index(u64 cookie, unsigned long *shift)
+{
+ u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT;
+
+ cookie &= ~COOKIE_PGSZ_CODE;
+
+ *shift = szcode * 3;
+
+ return (cookie >> (13ULL + (szcode * 3ULL)));
+}
+
+static struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu,
+ unsigned long npages)
+{
+ long entry;
+
+ entry = arena_alloc(iommu, npages);
+ if (unlikely(entry < 0))
+ return NULL;
+
+ return iommu->page_table + entry;
+}
+
+static u64 perm_to_mte(unsigned int map_perm)
+{
+ u64 mte_base;
+
+ mte_base = pagesize_code();
+
+ if (map_perm & LDC_MAP_SHADOW) {
+ if (map_perm & LDC_MAP_R)
+ mte_base |= LDC_MTE_COPY_R;
+ if (map_perm & LDC_MAP_W)
+ mte_base |= LDC_MTE_COPY_W;
+ }
+ if (map_perm & LDC_MAP_DIRECT) {
+ if (map_perm & LDC_MAP_R)
+ mte_base |= LDC_MTE_READ;
+ if (map_perm & LDC_MAP_W)
+ mte_base |= LDC_MTE_WRITE;
+ if (map_perm & LDC_MAP_X)
+ mte_base |= LDC_MTE_EXEC;
+ }
+ if (map_perm & LDC_MAP_IO) {
+ if (map_perm & LDC_MAP_R)
+ mte_base |= LDC_MTE_IOMMU_R;
+ if (map_perm & LDC_MAP_W)
+ mte_base |= LDC_MTE_IOMMU_W;
+ }
+
+ return mte_base;
+}
+
+static int pages_in_region(unsigned long base, long len)
+{
+ int count = 0;
+
+ do {
+ unsigned long new = (base + PAGE_SIZE) & PAGE_MASK;
+
+ len -= (new - base);
+ base = new;
+ count++;
+ } while (len > 0);
+
+ return count;
+}
+
+struct cookie_state {
+ struct ldc_mtable_entry *page_table;
+ struct ldc_trans_cookie *cookies;
+ u64 mte_base;
+ u64 prev_cookie;
+ u32 pte_idx;
+ u32 nc;
+};
+
+static void fill_cookies(struct cookie_state *sp, unsigned long pa,
+ unsigned long off, unsigned long len)
+{
+ do {
+ unsigned long tlen, new = pa + PAGE_SIZE;
+ u64 this_cookie;
+
+ sp->page_table[sp->pte_idx].mte = sp->mte_base | pa;
+
+ tlen = PAGE_SIZE;
+ if (off)
+ tlen = PAGE_SIZE - off;
+ if (tlen > len)
+ tlen = len;
+
+ this_cookie = make_cookie(sp->pte_idx,
+ pagesize_code(), off);
+
+ off = 0;
+
+ if (this_cookie == sp->prev_cookie) {
+ sp->cookies[sp->nc - 1].cookie_size += tlen;
+ } else {
+ sp->cookies[sp->nc].cookie_addr = this_cookie;
+ sp->cookies[sp->nc].cookie_size = tlen;
+ sp->nc++;
+ }
+ sp->prev_cookie = this_cookie + tlen;
+
+ sp->pte_idx++;
+
+ len -= tlen;
+ pa = new;
+ } while (len > 0);
+}
+
+static int sg_count_one(struct scatterlist *sg)
+{
+ unsigned long base = page_to_pfn(sg->page) << PAGE_SHIFT;
+ long len = sg->length;
+
+ if ((sg->offset | len) & (8UL - 1))
+ return -EFAULT;
+
+ return pages_in_region(base + sg->offset, len);
+}
+
+static int sg_count_pages(struct scatterlist *sg, int num_sg)
+{
+ int count;
+ int i;
+
+ count = 0;
+ for (i = 0; i < num_sg; i++) {
+ int err = sg_count_one(sg + i);
+ if (err < 0)
+ return err;
+ count += err;
+ }
+
+ return count;
+}
+
+int ldc_map_sg(struct ldc_channel *lp,
+ struct scatterlist *sg, int num_sg,
+ struct ldc_trans_cookie *cookies, int ncookies,
+ unsigned int map_perm)
+{
+ unsigned long i, npages, flags;
+ struct ldc_mtable_entry *base;
+ struct cookie_state state;
+ struct ldc_iommu *iommu;
+ int err;
+
+ if (map_perm & ~LDC_MAP_ALL)
+ return -EINVAL;
+
+ err = sg_count_pages(sg, num_sg);
+ if (err < 0)
+ return err;
+
+ npages = err;
+ if (err > ncookies)
+ return -EMSGSIZE;
+
+ iommu = &lp->iommu;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+ base = alloc_npages(iommu, npages);
+ spin_unlock_irqrestore(&iommu->lock, flags);
+
+ if (!base)
+ return -ENOMEM;
+
+ state.page_table = iommu->page_table;
+ state.cookies = cookies;
+ state.mte_base = perm_to_mte(map_perm);
+ state.prev_cookie = ~(u64)0;
+ state.pte_idx = (base - iommu->page_table);
+ state.nc = 0;
+
+ for (i = 0; i < num_sg; i++)
+ fill_cookies(&state, page_to_pfn(sg[i].page) << PAGE_SHIFT,
+ sg[i].offset, sg[i].length);
+
+ return state.nc;
+}
+EXPORT_SYMBOL(ldc_map_sg);
+
+int ldc_map_single(struct ldc_channel *lp,
+ void *buf, unsigned int len,
+ struct ldc_trans_cookie *cookies, int ncookies,
+ unsigned int map_perm)
+{
+ unsigned long npages, pa, flags;
+ struct ldc_mtable_entry *base;
+ struct cookie_state state;
+ struct ldc_iommu *iommu;
+
+ if ((map_perm & ~LDC_MAP_ALL) || (ncookies < 1))
+ return -EINVAL;
+
+ pa = __pa(buf);
+ if ((pa | len) & (8UL - 1))
+ return -EFAULT;
+
+ npages = pages_in_region(pa, len);
+
+ iommu = &lp->iommu;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+ base = alloc_npages(iommu, npages);
+ spin_unlock_irqrestore(&iommu->lock, flags);
+
+ if (!base)
+ return -ENOMEM;
+
+ state.page_table = iommu->page_table;
+ state.cookies = cookies;
+ state.mte_base = perm_to_mte(map_perm);
+ state.prev_cookie = ~(u64)0;
+ state.pte_idx = (base - iommu->page_table);
+ state.nc = 0;
+ fill_cookies(&state, (pa & PAGE_MASK), (pa & ~PAGE_MASK), len);
+ BUG_ON(state.nc != 1);
+
+ return state.nc;
+}
+EXPORT_SYMBOL(ldc_map_single);
+
+static void free_npages(unsigned long id, struct ldc_iommu *iommu,
+ u64 cookie, u64 size)
+{
+ struct iommu_arena *arena = &iommu->arena;
+ unsigned long i, shift, index, npages;
+ struct ldc_mtable_entry *base;
+
+ npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT;
+ index = cookie_to_index(cookie, &shift);
+ base = iommu->page_table + index;
+
+ BUG_ON(index > arena->limit ||
+ (index + npages) > arena->limit);
+
+ for (i = 0; i < npages; i++) {
+ if (base->cookie)
+ sun4v_ldc_revoke(id, cookie + (i << shift),
+ base->cookie);
+ base->mte = 0;
+ __clear_bit(index + i, arena->map);
+ }
+}
+
+void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies,
+ int ncookies)
+{
+ struct ldc_iommu *iommu = &lp->iommu;
+ unsigned long flags;
+ int i;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+ for (i = 0; i < ncookies; i++) {
+ u64 addr = cookies[i].cookie_addr;
+ u64 size = cookies[i].cookie_size;
+
+ free_npages(lp->id, iommu, addr, size);
+ }
+ spin_unlock_irqrestore(&iommu->lock, flags);
+}
+EXPORT_SYMBOL(ldc_unmap);
+
+int ldc_copy(struct ldc_channel *lp, int copy_dir,
+ void *buf, unsigned int len, unsigned long offset,
+ struct ldc_trans_cookie *cookies, int ncookies)
+{
+ unsigned int orig_len;
+ unsigned long ra;
+ int i;
+
+ if (copy_dir != LDC_COPY_IN && copy_dir != LDC_COPY_OUT) {
+ printk(KERN_ERR PFX "ldc_copy: ID[%lu] Bad copy_dir[%d]\n",
+ lp->id, copy_dir);
+ return -EINVAL;
+ }
+
+ ra = __pa(buf);
+ if ((ra | len | offset) & (8UL - 1)) {
+ printk(KERN_ERR PFX "ldc_copy: ID[%lu] Unaligned buffer "
+ "ra[%lx] len[%x] offset[%lx]\n",
+ lp->id, ra, len, offset);
+ return -EFAULT;
+ }
+
+ if (lp->hs_state != LDC_HS_COMPLETE ||
+ (lp->flags & LDC_FLAG_RESET)) {
+ printk(KERN_ERR PFX "ldc_copy: ID[%lu] Link down hs_state[%x] "
+ "flags[%x]\n", lp->id, lp->hs_state, lp->flags);
+ return -ECONNRESET;
+ }
+
+ orig_len = len;
+ for (i = 0; i < ncookies; i++) {
+ unsigned long cookie_raddr = cookies[i].cookie_addr;
+ unsigned long this_len = cookies[i].cookie_size;
+ unsigned long actual_len;
+
+ if (unlikely(offset)) {
+ unsigned long this_off = offset;
+
+ if (this_off > this_len)
+ this_off = this_len;
+
+ offset -= this_off;
+ this_len -= this_off;
+ if (!this_len)
+ continue;
+ cookie_raddr += this_off;
+ }
+
+ if (this_len > len)
+ this_len = len;
+
+ while (1) {
+ unsigned long hv_err;
+
+ hv_err = sun4v_ldc_copy(lp->id, copy_dir,
+ cookie_raddr, ra,
+ this_len, &actual_len);
+ if (unlikely(hv_err)) {
+ printk(KERN_ERR PFX "ldc_copy: ID[%lu] "
+ "HV error %lu\n",
+ lp->id, hv_err);
+ if (lp->hs_state != LDC_HS_COMPLETE ||
+ (lp->flags & LDC_FLAG_RESET))
+ return -ECONNRESET;
+ else
+ return -EFAULT;
+ }
+
+ cookie_raddr += actual_len;
+ ra += actual_len;
+ len -= actual_len;
+ if (actual_len == this_len)
+ break;
+
+ this_len -= actual_len;
+ }
+
+ if (!len)
+ break;
+ }
+
+ /* It is caller policy what to do about short copies.
+ * For example, a networking driver can declare the
+ * packet a runt and drop it.
+ */
+
+ return orig_len - len;
+}
+EXPORT_SYMBOL(ldc_copy);
+
+void *ldc_alloc_exp_dring(struct ldc_channel *lp, unsigned int len,
+ struct ldc_trans_cookie *cookies, int *ncookies,
+ unsigned int map_perm)
+{
+ void *buf;
+ int err;
+
+ if (len & (8UL - 1))
+ return ERR_PTR(-EINVAL);
+
+ buf = kzalloc(len, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+
+ err = ldc_map_single(lp, buf, len, cookies, *ncookies, map_perm);
+ if (err < 0) {
+ kfree(buf);
+ return ERR_PTR(err);
+ }
+ *ncookies = err;
+
+ return buf;
+}
+EXPORT_SYMBOL(ldc_alloc_exp_dring);
+
+void ldc_free_exp_dring(struct ldc_channel *lp, void *buf, unsigned int len,
+ struct ldc_trans_cookie *cookies, int ncookies)
+{
+ ldc_unmap(lp, cookies, ncookies);
+ kfree(buf);
+}
+EXPORT_SYMBOL(ldc_free_exp_dring);
+
+static int __init ldc_init(void)
+{
+ struct mdesc_node *mp;
+ unsigned long major, minor;
+ const u64 *v;
+
+ mp = md_find_node_by_name(NULL, "platform");
+ if (!mp)
+ return -ENODEV;
+
+ v = md_get_property(mp, "domaining-enabled", NULL);
+ if (!v)
+ return -ENODEV;
+
+ major = 1;
+ minor = 0;
+ if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) {
+ printk(KERN_INFO PFX "Could not register LDOM hvapi.\n");
+ return -ENODEV;
+ }
+
+ printk(KERN_INFO "%s", version);
+
+ if (!*v) {
+ printk(KERN_INFO PFX "Domaining disabled.\n");
+ return -ENODEV;
+ }
+ ldom_domaining_enabled = 1;
+
+ return 0;
+}
+
+core_initcall(ldc_init);
--- /dev/null
+/* 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->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;
+ const u64 *id;
+
+ id = md_get_property(vio->endpoint, "id", NULL);
+ if (!id) {
+ printk(KERN_ERR "%s: Channel lacks id property.\n",
+ vio->name);
+ return -ENODEV;
+ }
+
+ vio->channel_id = *id;
+
+ cfg.rx_irq = vio->rx_irq;
+ cfg.tx_irq = vio->tx_irq;
+
+ lp = ldc_alloc(vio->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);
+ if (err)
+ printk(KERN_WARNING "%s: Port %lu bind failed, "
+ "err=%d\n",
+ vio->name, vio->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->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 mdesc_node *channel_endpoint,
+ 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 (!channel_endpoint)
+ 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->endpoint = channel_endpoint;
+ vio->tx_irq = channel_endpoint->irqs[0];
+ vio->rx_irq = channel_endpoint->irqs[1];
+
+ 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);