v4.19.13 snapshot.
diff --git a/arch/sparc/kernel/ldc.c b/arch/sparc/kernel/ldc.c
new file mode 100644
index 0000000..c0fa3ef
--- /dev/null
+++ b/arch/sparc/kernel/ldc.c
@@ -0,0 +1,2428 @@
+// SPDX-License-Identifier: GPL-2.0
+/* ldc.c: Logical Domain Channel link-layer protocol driver.
+ *
+ * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
+ */
+
+#include <linux/kernel.h>
+#include <linux/export.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 <linux/bitmap.h>
+#include <asm/iommu-common.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 "1.1"
+#define DRV_MODULE_RELDATE "July 22, 2008"
+
+#define COOKIE_PGSZ_CODE 0xf000000000000000ULL
+#define COOKIE_PGSZ_CODE_SHIFT 60ULL
+
+
+static char version[] =
+ DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
+
+/* 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 ldc_unmap. */
+ spinlock_t lock;
+ struct ldc_mtable_entry *page_table;
+ struct iommu_map_table iommu_map_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;
+
+#define LDC_IRQ_NAME_MAX 32
+ char rx_irq_name[LDC_IRQ_NAME_MAX];
+ char tx_irq_name[LDC_IRQ_NAME_MAX];
+
+ 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)
+
+#define LDC_ABORT(lp) ldc_abort((lp), __func__)
+
+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 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_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 + 1;
+ 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, const char *msg)
+{
+ unsigned long hv_err;
+
+ ldcdbg(STATE, "ABORT[%s]\n", msg);
+ ldc_print(lp);
+
+ /* 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;
+ struct ldc_packet *p;
+ unsigned long new_tail;
+
+ if (vp->major == 0 && vp->minor == 0)
+ return LDC_ABORT(lp);
+
+ vap = find_by_major(vp->major);
+ if (!vap)
+ return LDC_ABORT(lp);
+
+ p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
+ vap, sizeof(*vap),
+ &new_tail);
+ if (!p)
+ return LDC_ABORT(lp);
+
+ return send_tx_packet(lp, p, new_tail);
+}
+
+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_tail)
+ 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, flags;
+ unsigned int event_mask;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ orig_state = lp->chan_state;
+
+ /* We should probably check for hypervisor errors here and
+ * reset the LDC channel if we get one.
+ */
+ 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);
+
+ /*
+ * Generate an LDC_EVENT_UP event if the channel
+ * was not already up.
+ */
+ if (orig_state != LDC_CHANNEL_UP) {
+ 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) ldc_rx_reset(lp);
+ 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, orig_state;
+ unsigned int event_mask = 0;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ orig_state = lp->chan_state;
+
+ /* We should probably check for hypervisor errors here and
+ * reset the LDC channel if we get one.
+ */
+ 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);
+
+ /*
+ * Generate an LDC_EVENT_UP event if the channel
+ * was not already up.
+ */
+ if (orig_state != LDC_CHANNEL_UP) {
+ event_mask |= LDC_EVENT_UP;
+ orig_state = lp->chan_state;
+ }
+ }
+
+ 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;
+
+ hlist_for_each_entry(lp, &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);
+}
+
+static unsigned long ldc_cookie_to_index(u64 cookie, void *arg)
+{
+ u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT;
+ /* struct ldc_iommu *ldc_iommu = (struct ldc_iommu *)arg; */
+
+ cookie &= ~COOKIE_PGSZ_CODE;
+
+ return (cookie >> (13ULL + (szcode * 3ULL)));
+}
+
+static void ldc_demap(struct ldc_iommu *iommu, unsigned long id, u64 cookie,
+ unsigned long entry, unsigned long npages)
+{
+ struct ldc_mtable_entry *base;
+ unsigned long i, shift;
+
+ shift = (cookie >> COOKIE_PGSZ_CODE_SHIFT) * 3;
+ base = iommu->page_table + entry;
+ for (i = 0; i < npages; i++) {
+ if (base->cookie)
+ sun4v_ldc_revoke(id, cookie + (i << shift),
+ base->cookie);
+ base->mte = 0;
+ }
+}
+
+/* XXX Make this configurable... XXX */
+#define LDC_IOTABLE_SIZE (8 * 1024)
+
+static int ldc_iommu_init(const char *name, struct ldc_channel *lp)
+{
+ unsigned long sz, num_tsb_entries, tsbsize, order;
+ struct ldc_iommu *ldc_iommu = &lp->iommu;
+ struct iommu_map_table *iommu = &ldc_iommu->iommu_map_table;
+ 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(&ldc_iommu->lock);
+
+ sz = num_tsb_entries / 8;
+ sz = (sz + 7UL) & ~7UL;
+ iommu->map = kzalloc(sz, GFP_KERNEL);
+ if (!iommu->map) {
+ printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz);
+ return -ENOMEM;
+ }
+ iommu_tbl_pool_init(iommu, num_tsb_entries, PAGE_SHIFT,
+ NULL, false /* no large pool */,
+ 1 /* npools */,
+ true /* skip span boundary check */);
+
+ 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);
+
+ ldc_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);
+ ldc_iommu->page_table = NULL;
+
+out_free_map:
+ kfree(iommu->map);
+ iommu->map = NULL;
+
+ return err;
+}
+
+static void ldc_iommu_release(struct ldc_channel *lp)
+{
+ struct ldc_iommu *ldc_iommu = &lp->iommu;
+ struct iommu_map_table *iommu = &ldc_iommu->iommu_map_table;
+ unsigned long num_tsb_entries, tsbsize, order;
+
+ (void) sun4v_ldc_set_map_table(lp->id, 0, 0);
+
+ num_tsb_entries = iommu->poolsize * iommu->nr_pools;
+ tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
+ order = get_order(tsbsize);
+
+ free_pages((unsigned long) ldc_iommu->page_table, order);
+ ldc_iommu->page_table = NULL;
+
+ kfree(iommu->map);
+ iommu->map = NULL;
+}
+
+struct ldc_channel *ldc_alloc(unsigned long id,
+ const struct ldc_channel_config *cfgp,
+ void *event_arg,
+ const char *name)
+{
+ 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;
+ if (!name)
+ 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_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(name, 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);
+
+ snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name);
+ snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name);
+
+ err = request_irq(lp->cfg.rx_irq, ldc_rx, 0,
+ lp->rx_irq_name, lp);
+ if (err)
+ goto out_free_txq;
+
+ err = request_irq(lp->cfg.tx_irq, ldc_tx, 0,
+ lp->tx_irq_name, lp);
+ if (err) {
+ free_irq(lp->cfg.rx_irq, lp);
+ goto out_free_txq;
+ }
+
+ return lp;
+
+out_free_txq:
+ free_queue(lp->tx_num_entries, lp->tx_base);
+
+out_free_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_unbind(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);
+ lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
+ }
+
+ 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;
+ }
+
+ ldc_set_state(lp, LDC_STATE_INIT);
+}
+EXPORT_SYMBOL(ldc_unbind);
+
+void ldc_free(struct ldc_channel *lp)
+{
+ ldc_unbind(lp);
+ hlist_del(&lp->list);
+ 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;
+
+ if (lp->state != LDC_STATE_INIT)
+ return -EINVAL;
+
+ spin_lock_irqsave(&lp->lock, flags);
+
+ enable_irq(lp->cfg.rx_irq);
+ enable_irq(lp->cfg.tx_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_irqs;
+
+ hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
+ if (hv_err)
+ goto out_free_irqs;
+
+ 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);
+
+ if (lp->cfg.mode == LDC_MODE_RAW) {
+ /*
+ * There is no handshake in RAW mode, so handshake
+ * is completed.
+ */
+ lp->hs_state = LDC_HS_COMPLETE;
+ }
+
+ 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_irqs:
+ lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
+ free_irq(lp->cfg.tx_irq, lp);
+ free_irq(lp->cfg.rx_irq, lp);
+
+ 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 = ((lp->hs_state > LDC_HS_OPEN) ? 0 : -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);
+
+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;
+}
+EXPORT_SYMBOL(ldc_set_state);
+
+int ldc_mode(struct ldc_channel *lp)
+{
+ return lp->cfg.mode;
+}
+EXPORT_SYMBOL(ldc_mode);
+
+int ldc_rx_reset(struct ldc_channel *lp)
+{
+ return __set_rx_head(lp, lp->rx_tail);
+}
+EXPORT_SYMBOL(ldc_rx_reset);
+
+void __ldc_print(struct ldc_channel *lp, const char *caller)
+{
+ pr_info("%s: id=0x%lx flags=0x%x state=%s cstate=0x%lx hsstate=0x%x\n"
+ "\trx_h=0x%lx rx_t=0x%lx rx_n=%ld\n"
+ "\ttx_h=0x%lx tx_t=0x%lx tx_n=%ld\n"
+ "\trcv_nxt=%u snd_nxt=%u\n",
+ caller, lp->id, lp->flags, state_to_str(lp->state),
+ lp->chan_state, lp->hs_state,
+ lp->rx_head, lp->rx_tail, lp->rx_num_entries,
+ lp->tx_head, lp->tx_tail, lp->tx_num_entries,
+ lp->rcv_nxt, lp->snd_nxt);
+}
+EXPORT_SYMBOL(__ldc_print);
+
+static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size)
+{
+ struct ldc_packet *p;
+ unsigned long new_tail, hv_err;
+ 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 (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 = ldc_rx_reset(lp);
+ 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);
+
+ 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 "
+ "head[%lx] tail[%lx] chan_state[%lx]\n",
+ dummy, lp->rx_tail, lp->chan_state);
+ 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 void send_data_ack(struct ldc_channel *lp)
+{
+ unsigned long new_tail;
+ struct ldc_packet *p;
+
+ p = data_get_tx_packet(lp, &new_tail);
+ if (likely(p)) {
+ int err;
+
+ memset(p, 0, sizeof(*p));
+ p->type = LDC_DATA;
+ p->stype = LDC_ACK;
+ p->ctrl = 0;
+ p->seqid = lp->snd_nxt + 1;
+ p->u.r.ackid = lp->rcv_nxt;
+
+ err = send_tx_packet(lp, p, new_tail);
+ if (!err)
+ lp->snd_nxt++;
+ }
+}
+
+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:%08x] "
+ "rcv_nxt[%08x]\n",
+ p->type,
+ p->stype,
+ p->ctrl,
+ p->env,
+ p->seqid,
+ p->u.r.ackid,
+ 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 this is a control-only packet, there is nothing
+ * else to do but advance the rx queue since the packet
+ * was already processed above.
+ */
+ if (!(p->type & LDC_DATA)) {
+ new = rx_advance(lp, new);
+ break;
+ }
+ 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);
+ err = rx_set_head(lp, new);
+ if (err)
+ break;
+ 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;
+ if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE)
+ send_data_ack(lp);
+ }
+
+ 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, lp->cfg.mtu);
+ 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;
+
+ ldcdbg(RX, "%s: entered size=%d\n", __func__, size);
+
+ 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);
+
+ ldcdbg(RX, "%s: mode=%d, head=%lu, tail=%lu rv=%d\n", __func__,
+ lp->cfg.mode, lp->rx_head, lp->rx_tail, err);
+
+ return err;
+}
+EXPORT_SYMBOL(ldc_read);
+
+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 struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu,
+ unsigned long npages)
+{
+ long entry;
+
+ entry = iommu_tbl_range_alloc(NULL, &iommu->iommu_map_table,
+ npages, NULL, (unsigned long)-1, 0);
+ if (unlikely(entry == IOMMU_ERROR_CODE))
+ 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(sg)) << 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;
+ struct ldc_mtable_entry *base;
+ struct cookie_state state;
+ struct ldc_iommu *iommu;
+ int err;
+ struct scatterlist *s;
+
+ 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;
+
+ base = alloc_npages(iommu, npages);
+
+ 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_each_sg(sg, s, num_sg, i) {
+ fill_cookies(&state, page_to_pfn(sg_page(s)) << PAGE_SHIFT,
+ s->offset, s->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;
+ 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;
+
+ base = alloc_npages(iommu, npages);
+
+ 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 > ncookies);
+
+ return state.nc;
+}
+EXPORT_SYMBOL(ldc_map_single);
+
+
+static void free_npages(unsigned long id, struct ldc_iommu *iommu,
+ u64 cookie, u64 size)
+{
+ unsigned long npages, entry;
+
+ npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT;
+
+ entry = ldc_cookie_to_index(cookie, iommu);
+ ldc_demap(iommu, id, cookie, entry, npages);
+ iommu_tbl_range_free(&iommu->iommu_map_table, cookie, npages, entry);
+}
+
+void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies,
+ int ncookies)
+{
+ struct ldc_iommu *iommu = &lp->iommu;
+ int i;
+ unsigned long flags;
+
+ 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_ATOMIC);
+ 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)
+{
+ unsigned long major, minor;
+ struct mdesc_handle *hp;
+ const u64 *v;
+ int err;
+ u64 mp;
+
+ hp = mdesc_grab();
+ if (!hp)
+ return -ENODEV;
+
+ mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
+ err = -ENODEV;
+ if (mp == MDESC_NODE_NULL)
+ goto out;
+
+ v = mdesc_get_property(hp, mp, "domaining-enabled", NULL);
+ if (!v)
+ goto out;
+
+ major = 1;
+ minor = 0;
+ if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) {
+ printk(KERN_INFO PFX "Could not register LDOM hvapi.\n");
+ goto out;
+ }
+
+ printk(KERN_INFO "%s", version);
+
+ if (!*v) {
+ printk(KERN_INFO PFX "Domaining disabled.\n");
+ goto out;
+ }
+ ldom_domaining_enabled = 1;
+ err = 0;
+
+out:
+ mdesc_release(hp);
+ return err;
+}
+
+core_initcall(ldc_init);