net: kalmia: fix memory leaks
[linux/fpc-iii.git] / arch / sparc / kernel / ldc.c
blob9cc600b2d68ced3bf7817f0edf6c498f8eb1e67f
1 /* ldc.c: Logical Domain Channel link-layer protocol driver.
3 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
4 */
6 #include <linux/kernel.h>
7 #include <linux/export.h>
8 #include <linux/slab.h>
9 #include <linux/spinlock.h>
10 #include <linux/delay.h>
11 #include <linux/errno.h>
12 #include <linux/string.h>
13 #include <linux/scatterlist.h>
14 #include <linux/interrupt.h>
15 #include <linux/list.h>
16 #include <linux/init.h>
17 #include <linux/bitmap.h>
18 #include <linux/iommu-common.h>
20 #include <asm/hypervisor.h>
21 #include <asm/iommu.h>
22 #include <asm/page.h>
23 #include <asm/ldc.h>
24 #include <asm/mdesc.h>
26 #define DRV_MODULE_NAME "ldc"
27 #define PFX DRV_MODULE_NAME ": "
28 #define DRV_MODULE_VERSION "1.1"
29 #define DRV_MODULE_RELDATE "July 22, 2008"
31 #define COOKIE_PGSZ_CODE 0xf000000000000000ULL
32 #define COOKIE_PGSZ_CODE_SHIFT 60ULL
35 static char version[] =
36 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
37 #define LDC_PACKET_SIZE 64
39 /* Packet header layout for unreliable and reliable mode frames.
40 * When in RAW mode, packets are simply straight 64-byte payloads
41 * with no headers.
43 struct ldc_packet {
44 u8 type;
45 #define LDC_CTRL 0x01
46 #define LDC_DATA 0x02
47 #define LDC_ERR 0x10
49 u8 stype;
50 #define LDC_INFO 0x01
51 #define LDC_ACK 0x02
52 #define LDC_NACK 0x04
54 u8 ctrl;
55 #define LDC_VERS 0x01 /* Link Version */
56 #define LDC_RTS 0x02 /* Request To Send */
57 #define LDC_RTR 0x03 /* Ready To Receive */
58 #define LDC_RDX 0x04 /* Ready for Data eXchange */
59 #define LDC_CTRL_MSK 0x0f
61 u8 env;
62 #define LDC_LEN 0x3f
63 #define LDC_FRAG_MASK 0xc0
64 #define LDC_START 0x40
65 #define LDC_STOP 0x80
67 u32 seqid;
69 union {
70 u8 u_data[LDC_PACKET_SIZE - 8];
71 struct {
72 u32 pad;
73 u32 ackid;
74 u8 r_data[LDC_PACKET_SIZE - 8 - 8];
75 } r;
76 } u;
79 struct ldc_version {
80 u16 major;
81 u16 minor;
84 /* Ordered from largest major to lowest. */
85 static struct ldc_version ver_arr[] = {
86 { .major = 1, .minor = 0 },
89 #define LDC_DEFAULT_MTU (4 * LDC_PACKET_SIZE)
90 #define LDC_DEFAULT_NUM_ENTRIES (PAGE_SIZE / LDC_PACKET_SIZE)
92 struct ldc_channel;
94 struct ldc_mode_ops {
95 int (*write)(struct ldc_channel *, const void *, unsigned int);
96 int (*read)(struct ldc_channel *, void *, unsigned int);
99 static const struct ldc_mode_ops raw_ops;
100 static const struct ldc_mode_ops nonraw_ops;
101 static const struct ldc_mode_ops stream_ops;
103 int ldom_domaining_enabled;
105 struct ldc_iommu {
106 /* Protects ldc_unmap. */
107 spinlock_t lock;
108 struct ldc_mtable_entry *page_table;
109 struct iommu_map_table iommu_map_table;
112 struct ldc_channel {
113 /* Protects all operations that depend upon channel state. */
114 spinlock_t lock;
116 unsigned long id;
118 u8 *mssbuf;
119 u32 mssbuf_len;
120 u32 mssbuf_off;
122 struct ldc_packet *tx_base;
123 unsigned long tx_head;
124 unsigned long tx_tail;
125 unsigned long tx_num_entries;
126 unsigned long tx_ra;
128 unsigned long tx_acked;
130 struct ldc_packet *rx_base;
131 unsigned long rx_head;
132 unsigned long rx_tail;
133 unsigned long rx_num_entries;
134 unsigned long rx_ra;
136 u32 rcv_nxt;
137 u32 snd_nxt;
139 unsigned long chan_state;
141 struct ldc_channel_config cfg;
142 void *event_arg;
144 const struct ldc_mode_ops *mops;
146 struct ldc_iommu iommu;
148 struct ldc_version ver;
150 u8 hs_state;
151 #define LDC_HS_CLOSED 0x00
152 #define LDC_HS_OPEN 0x01
153 #define LDC_HS_GOTVERS 0x02
154 #define LDC_HS_SENTRTR 0x03
155 #define LDC_HS_GOTRTR 0x04
156 #define LDC_HS_COMPLETE 0x10
158 u8 flags;
159 #define LDC_FLAG_ALLOCED_QUEUES 0x01
160 #define LDC_FLAG_REGISTERED_QUEUES 0x02
161 #define LDC_FLAG_REGISTERED_IRQS 0x04
162 #define LDC_FLAG_RESET 0x10
164 u8 mss;
165 u8 state;
167 #define LDC_IRQ_NAME_MAX 32
168 char rx_irq_name[LDC_IRQ_NAME_MAX];
169 char tx_irq_name[LDC_IRQ_NAME_MAX];
171 struct hlist_head mh_list;
173 struct hlist_node list;
176 #define ldcdbg(TYPE, f, a...) \
177 do { if (lp->cfg.debug & LDC_DEBUG_##TYPE) \
178 printk(KERN_INFO PFX "ID[%lu] " f, lp->id, ## a); \
179 } while (0)
181 static const char *state_to_str(u8 state)
183 switch (state) {
184 case LDC_STATE_INVALID:
185 return "INVALID";
186 case LDC_STATE_INIT:
187 return "INIT";
188 case LDC_STATE_BOUND:
189 return "BOUND";
190 case LDC_STATE_READY:
191 return "READY";
192 case LDC_STATE_CONNECTED:
193 return "CONNECTED";
194 default:
195 return "<UNKNOWN>";
199 static void ldc_set_state(struct ldc_channel *lp, u8 state)
201 ldcdbg(STATE, "STATE (%s) --> (%s)\n",
202 state_to_str(lp->state),
203 state_to_str(state));
205 lp->state = state;
208 static unsigned long __advance(unsigned long off, unsigned long num_entries)
210 off += LDC_PACKET_SIZE;
211 if (off == (num_entries * LDC_PACKET_SIZE))
212 off = 0;
214 return off;
217 static unsigned long rx_advance(struct ldc_channel *lp, unsigned long off)
219 return __advance(off, lp->rx_num_entries);
222 static unsigned long tx_advance(struct ldc_channel *lp, unsigned long off)
224 return __advance(off, lp->tx_num_entries);
227 static struct ldc_packet *handshake_get_tx_packet(struct ldc_channel *lp,
228 unsigned long *new_tail)
230 struct ldc_packet *p;
231 unsigned long t;
233 t = tx_advance(lp, lp->tx_tail);
234 if (t == lp->tx_head)
235 return NULL;
237 *new_tail = t;
239 p = lp->tx_base;
240 return p + (lp->tx_tail / LDC_PACKET_SIZE);
243 /* When we are in reliable or stream mode, have to track the next packet
244 * we haven't gotten an ACK for in the TX queue using tx_acked. We have
245 * to be careful not to stomp over the queue past that point. During
246 * the handshake, we don't have TX data packets pending in the queue
247 * and that's why handshake_get_tx_packet() need not be mindful of
248 * lp->tx_acked.
250 static unsigned long head_for_data(struct ldc_channel *lp)
252 if (lp->cfg.mode == LDC_MODE_STREAM)
253 return lp->tx_acked;
254 return lp->tx_head;
257 static int tx_has_space_for(struct ldc_channel *lp, unsigned int size)
259 unsigned long limit, tail, new_tail, diff;
260 unsigned int mss;
262 limit = head_for_data(lp);
263 tail = lp->tx_tail;
264 new_tail = tx_advance(lp, tail);
265 if (new_tail == limit)
266 return 0;
268 if (limit > new_tail)
269 diff = limit - new_tail;
270 else
271 diff = (limit +
272 ((lp->tx_num_entries * LDC_PACKET_SIZE) - new_tail));
273 diff /= LDC_PACKET_SIZE;
274 mss = lp->mss;
276 if (diff * mss < size)
277 return 0;
279 return 1;
282 static struct ldc_packet *data_get_tx_packet(struct ldc_channel *lp,
283 unsigned long *new_tail)
285 struct ldc_packet *p;
286 unsigned long h, t;
288 h = head_for_data(lp);
289 t = tx_advance(lp, lp->tx_tail);
290 if (t == h)
291 return NULL;
293 *new_tail = t;
295 p = lp->tx_base;
296 return p + (lp->tx_tail / LDC_PACKET_SIZE);
299 static int set_tx_tail(struct ldc_channel *lp, unsigned long tail)
301 unsigned long orig_tail = lp->tx_tail;
302 int limit = 1000;
304 lp->tx_tail = tail;
305 while (limit-- > 0) {
306 unsigned long err;
308 err = sun4v_ldc_tx_set_qtail(lp->id, tail);
309 if (!err)
310 return 0;
312 if (err != HV_EWOULDBLOCK) {
313 lp->tx_tail = orig_tail;
314 return -EINVAL;
316 udelay(1);
319 lp->tx_tail = orig_tail;
320 return -EBUSY;
323 /* This just updates the head value in the hypervisor using
324 * a polling loop with a timeout. The caller takes care of
325 * upating software state representing the head change, if any.
327 static int __set_rx_head(struct ldc_channel *lp, unsigned long head)
329 int limit = 1000;
331 while (limit-- > 0) {
332 unsigned long err;
334 err = sun4v_ldc_rx_set_qhead(lp->id, head);
335 if (!err)
336 return 0;
338 if (err != HV_EWOULDBLOCK)
339 return -EINVAL;
341 udelay(1);
344 return -EBUSY;
347 static int send_tx_packet(struct ldc_channel *lp,
348 struct ldc_packet *p,
349 unsigned long new_tail)
351 BUG_ON(p != (lp->tx_base + (lp->tx_tail / LDC_PACKET_SIZE)));
353 return set_tx_tail(lp, new_tail);
356 static struct ldc_packet *handshake_compose_ctrl(struct ldc_channel *lp,
357 u8 stype, u8 ctrl,
358 void *data, int dlen,
359 unsigned long *new_tail)
361 struct ldc_packet *p = handshake_get_tx_packet(lp, new_tail);
363 if (p) {
364 memset(p, 0, sizeof(*p));
365 p->type = LDC_CTRL;
366 p->stype = stype;
367 p->ctrl = ctrl;
368 if (data)
369 memcpy(p->u.u_data, data, dlen);
371 return p;
374 static int start_handshake(struct ldc_channel *lp)
376 struct ldc_packet *p;
377 struct ldc_version *ver;
378 unsigned long new_tail;
380 ver = &ver_arr[0];
382 ldcdbg(HS, "SEND VER INFO maj[%u] min[%u]\n",
383 ver->major, ver->minor);
385 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
386 ver, sizeof(*ver), &new_tail);
387 if (p) {
388 int err = send_tx_packet(lp, p, new_tail);
389 if (!err)
390 lp->flags &= ~LDC_FLAG_RESET;
391 return err;
393 return -EBUSY;
396 static int send_version_nack(struct ldc_channel *lp,
397 u16 major, u16 minor)
399 struct ldc_packet *p;
400 struct ldc_version ver;
401 unsigned long new_tail;
403 ver.major = major;
404 ver.minor = minor;
406 p = handshake_compose_ctrl(lp, LDC_NACK, LDC_VERS,
407 &ver, sizeof(ver), &new_tail);
408 if (p) {
409 ldcdbg(HS, "SEND VER NACK maj[%u] min[%u]\n",
410 ver.major, ver.minor);
412 return send_tx_packet(lp, p, new_tail);
414 return -EBUSY;
417 static int send_version_ack(struct ldc_channel *lp,
418 struct ldc_version *vp)
420 struct ldc_packet *p;
421 unsigned long new_tail;
423 p = handshake_compose_ctrl(lp, LDC_ACK, LDC_VERS,
424 vp, sizeof(*vp), &new_tail);
425 if (p) {
426 ldcdbg(HS, "SEND VER ACK maj[%u] min[%u]\n",
427 vp->major, vp->minor);
429 return send_tx_packet(lp, p, new_tail);
431 return -EBUSY;
434 static int send_rts(struct ldc_channel *lp)
436 struct ldc_packet *p;
437 unsigned long new_tail;
439 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTS, NULL, 0,
440 &new_tail);
441 if (p) {
442 p->env = lp->cfg.mode;
443 p->seqid = 0;
444 lp->rcv_nxt = 0;
446 ldcdbg(HS, "SEND RTS env[0x%x] seqid[0x%x]\n",
447 p->env, p->seqid);
449 return send_tx_packet(lp, p, new_tail);
451 return -EBUSY;
454 static int send_rtr(struct ldc_channel *lp)
456 struct ldc_packet *p;
457 unsigned long new_tail;
459 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTR, NULL, 0,
460 &new_tail);
461 if (p) {
462 p->env = lp->cfg.mode;
463 p->seqid = 0;
465 ldcdbg(HS, "SEND RTR env[0x%x] seqid[0x%x]\n",
466 p->env, p->seqid);
468 return send_tx_packet(lp, p, new_tail);
470 return -EBUSY;
473 static int send_rdx(struct ldc_channel *lp)
475 struct ldc_packet *p;
476 unsigned long new_tail;
478 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RDX, NULL, 0,
479 &new_tail);
480 if (p) {
481 p->env = 0;
482 p->seqid = ++lp->snd_nxt;
483 p->u.r.ackid = lp->rcv_nxt;
485 ldcdbg(HS, "SEND RDX env[0x%x] seqid[0x%x] ackid[0x%x]\n",
486 p->env, p->seqid, p->u.r.ackid);
488 return send_tx_packet(lp, p, new_tail);
490 return -EBUSY;
493 static int send_data_nack(struct ldc_channel *lp, struct ldc_packet *data_pkt)
495 struct ldc_packet *p;
496 unsigned long new_tail;
497 int err;
499 p = data_get_tx_packet(lp, &new_tail);
500 if (!p)
501 return -EBUSY;
502 memset(p, 0, sizeof(*p));
503 p->type = data_pkt->type;
504 p->stype = LDC_NACK;
505 p->ctrl = data_pkt->ctrl & LDC_CTRL_MSK;
506 p->seqid = lp->snd_nxt + 1;
507 p->u.r.ackid = lp->rcv_nxt;
509 ldcdbg(HS, "SEND DATA NACK type[0x%x] ctl[0x%x] seq[0x%x] ack[0x%x]\n",
510 p->type, p->ctrl, p->seqid, p->u.r.ackid);
512 err = send_tx_packet(lp, p, new_tail);
513 if (!err)
514 lp->snd_nxt++;
516 return err;
519 static int ldc_abort(struct ldc_channel *lp)
521 unsigned long hv_err;
523 ldcdbg(STATE, "ABORT\n");
525 /* We report but do not act upon the hypervisor errors because
526 * there really isn't much we can do if they fail at this point.
528 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
529 if (hv_err)
530 printk(KERN_ERR PFX "ldc_abort: "
531 "sun4v_ldc_tx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
532 lp->id, lp->tx_ra, lp->tx_num_entries, hv_err);
534 hv_err = sun4v_ldc_tx_get_state(lp->id,
535 &lp->tx_head,
536 &lp->tx_tail,
537 &lp->chan_state);
538 if (hv_err)
539 printk(KERN_ERR PFX "ldc_abort: "
540 "sun4v_ldc_tx_get_state(%lx,...) failed, err=%lu\n",
541 lp->id, hv_err);
543 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
544 if (hv_err)
545 printk(KERN_ERR PFX "ldc_abort: "
546 "sun4v_ldc_rx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
547 lp->id, lp->rx_ra, lp->rx_num_entries, hv_err);
549 /* Refetch the RX queue state as well, because we could be invoked
550 * here in the queue processing context.
552 hv_err = sun4v_ldc_rx_get_state(lp->id,
553 &lp->rx_head,
554 &lp->rx_tail,
555 &lp->chan_state);
556 if (hv_err)
557 printk(KERN_ERR PFX "ldc_abort: "
558 "sun4v_ldc_rx_get_state(%lx,...) failed, err=%lu\n",
559 lp->id, hv_err);
561 return -ECONNRESET;
564 static struct ldc_version *find_by_major(u16 major)
566 struct ldc_version *ret = NULL;
567 int i;
569 for (i = 0; i < ARRAY_SIZE(ver_arr); i++) {
570 struct ldc_version *v = &ver_arr[i];
571 if (v->major <= major) {
572 ret = v;
573 break;
576 return ret;
579 static int process_ver_info(struct ldc_channel *lp, struct ldc_version *vp)
581 struct ldc_version *vap;
582 int err;
584 ldcdbg(HS, "GOT VERSION INFO major[%x] minor[%x]\n",
585 vp->major, vp->minor);
587 if (lp->hs_state == LDC_HS_GOTVERS) {
588 lp->hs_state = LDC_HS_OPEN;
589 memset(&lp->ver, 0, sizeof(lp->ver));
592 vap = find_by_major(vp->major);
593 if (!vap) {
594 err = send_version_nack(lp, 0, 0);
595 } else if (vap->major != vp->major) {
596 err = send_version_nack(lp, vap->major, vap->minor);
597 } else {
598 struct ldc_version ver = *vp;
599 if (ver.minor > vap->minor)
600 ver.minor = vap->minor;
601 err = send_version_ack(lp, &ver);
602 if (!err) {
603 lp->ver = ver;
604 lp->hs_state = LDC_HS_GOTVERS;
607 if (err)
608 return ldc_abort(lp);
610 return 0;
613 static int process_ver_ack(struct ldc_channel *lp, struct ldc_version *vp)
615 ldcdbg(HS, "GOT VERSION ACK major[%x] minor[%x]\n",
616 vp->major, vp->minor);
618 if (lp->hs_state == LDC_HS_GOTVERS) {
619 if (lp->ver.major != vp->major ||
620 lp->ver.minor != vp->minor)
621 return ldc_abort(lp);
622 } else {
623 lp->ver = *vp;
624 lp->hs_state = LDC_HS_GOTVERS;
626 if (send_rts(lp))
627 return ldc_abort(lp);
628 return 0;
631 static int process_ver_nack(struct ldc_channel *lp, struct ldc_version *vp)
633 struct ldc_version *vap;
634 struct ldc_packet *p;
635 unsigned long new_tail;
637 if (vp->major == 0 && vp->minor == 0)
638 return ldc_abort(lp);
640 vap = find_by_major(vp->major);
641 if (!vap)
642 return ldc_abort(lp);
644 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
645 vap, sizeof(*vap),
646 &new_tail);
647 if (!p)
648 return ldc_abort(lp);
650 return send_tx_packet(lp, p, new_tail);
653 static int process_version(struct ldc_channel *lp,
654 struct ldc_packet *p)
656 struct ldc_version *vp;
658 vp = (struct ldc_version *) p->u.u_data;
660 switch (p->stype) {
661 case LDC_INFO:
662 return process_ver_info(lp, vp);
664 case LDC_ACK:
665 return process_ver_ack(lp, vp);
667 case LDC_NACK:
668 return process_ver_nack(lp, vp);
670 default:
671 return ldc_abort(lp);
675 static int process_rts(struct ldc_channel *lp,
676 struct ldc_packet *p)
678 ldcdbg(HS, "GOT RTS stype[%x] seqid[%x] env[%x]\n",
679 p->stype, p->seqid, p->env);
681 if (p->stype != LDC_INFO ||
682 lp->hs_state != LDC_HS_GOTVERS ||
683 p->env != lp->cfg.mode)
684 return ldc_abort(lp);
686 lp->snd_nxt = p->seqid;
687 lp->rcv_nxt = p->seqid;
688 lp->hs_state = LDC_HS_SENTRTR;
689 if (send_rtr(lp))
690 return ldc_abort(lp);
692 return 0;
695 static int process_rtr(struct ldc_channel *lp,
696 struct ldc_packet *p)
698 ldcdbg(HS, "GOT RTR stype[%x] seqid[%x] env[%x]\n",
699 p->stype, p->seqid, p->env);
701 if (p->stype != LDC_INFO ||
702 p->env != lp->cfg.mode)
703 return ldc_abort(lp);
705 lp->snd_nxt = p->seqid;
706 lp->hs_state = LDC_HS_COMPLETE;
707 ldc_set_state(lp, LDC_STATE_CONNECTED);
708 send_rdx(lp);
710 return LDC_EVENT_UP;
713 static int rx_seq_ok(struct ldc_channel *lp, u32 seqid)
715 return lp->rcv_nxt + 1 == seqid;
718 static int process_rdx(struct ldc_channel *lp,
719 struct ldc_packet *p)
721 ldcdbg(HS, "GOT RDX stype[%x] seqid[%x] env[%x] ackid[%x]\n",
722 p->stype, p->seqid, p->env, p->u.r.ackid);
724 if (p->stype != LDC_INFO ||
725 !(rx_seq_ok(lp, p->seqid)))
726 return ldc_abort(lp);
728 lp->rcv_nxt = p->seqid;
730 lp->hs_state = LDC_HS_COMPLETE;
731 ldc_set_state(lp, LDC_STATE_CONNECTED);
733 return LDC_EVENT_UP;
736 static int process_control_frame(struct ldc_channel *lp,
737 struct ldc_packet *p)
739 switch (p->ctrl) {
740 case LDC_VERS:
741 return process_version(lp, p);
743 case LDC_RTS:
744 return process_rts(lp, p);
746 case LDC_RTR:
747 return process_rtr(lp, p);
749 case LDC_RDX:
750 return process_rdx(lp, p);
752 default:
753 return ldc_abort(lp);
757 static int process_error_frame(struct ldc_channel *lp,
758 struct ldc_packet *p)
760 return ldc_abort(lp);
763 static int process_data_ack(struct ldc_channel *lp,
764 struct ldc_packet *ack)
766 unsigned long head = lp->tx_acked;
767 u32 ackid = ack->u.r.ackid;
769 while (1) {
770 struct ldc_packet *p = lp->tx_base + (head / LDC_PACKET_SIZE);
772 head = tx_advance(lp, head);
774 if (p->seqid == ackid) {
775 lp->tx_acked = head;
776 return 0;
778 if (head == lp->tx_tail)
779 return ldc_abort(lp);
782 return 0;
785 static void send_events(struct ldc_channel *lp, unsigned int event_mask)
787 if (event_mask & LDC_EVENT_RESET)
788 lp->cfg.event(lp->event_arg, LDC_EVENT_RESET);
789 if (event_mask & LDC_EVENT_UP)
790 lp->cfg.event(lp->event_arg, LDC_EVENT_UP);
791 if (event_mask & LDC_EVENT_DATA_READY)
792 lp->cfg.event(lp->event_arg, LDC_EVENT_DATA_READY);
795 static irqreturn_t ldc_rx(int irq, void *dev_id)
797 struct ldc_channel *lp = dev_id;
798 unsigned long orig_state, flags;
799 unsigned int event_mask;
801 spin_lock_irqsave(&lp->lock, flags);
803 orig_state = lp->chan_state;
805 /* We should probably check for hypervisor errors here and
806 * reset the LDC channel if we get one.
808 sun4v_ldc_rx_get_state(lp->id,
809 &lp->rx_head,
810 &lp->rx_tail,
811 &lp->chan_state);
813 ldcdbg(RX, "RX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
814 orig_state, lp->chan_state, lp->rx_head, lp->rx_tail);
816 event_mask = 0;
818 if (lp->cfg.mode == LDC_MODE_RAW &&
819 lp->chan_state == LDC_CHANNEL_UP) {
820 lp->hs_state = LDC_HS_COMPLETE;
821 ldc_set_state(lp, LDC_STATE_CONNECTED);
823 event_mask |= LDC_EVENT_UP;
825 orig_state = lp->chan_state;
828 /* If we are in reset state, flush the RX queue and ignore
829 * everything.
831 if (lp->flags & LDC_FLAG_RESET) {
832 (void) __set_rx_head(lp, lp->rx_tail);
833 goto out;
836 /* Once we finish the handshake, we let the ldc_read()
837 * paths do all of the control frame and state management.
838 * Just trigger the callback.
840 if (lp->hs_state == LDC_HS_COMPLETE) {
841 handshake_complete:
842 if (lp->chan_state != orig_state) {
843 unsigned int event = LDC_EVENT_RESET;
845 if (lp->chan_state == LDC_CHANNEL_UP)
846 event = LDC_EVENT_UP;
848 event_mask |= event;
850 if (lp->rx_head != lp->rx_tail)
851 event_mask |= LDC_EVENT_DATA_READY;
853 goto out;
856 if (lp->chan_state != orig_state)
857 goto out;
859 while (lp->rx_head != lp->rx_tail) {
860 struct ldc_packet *p;
861 unsigned long new;
862 int err;
864 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
866 switch (p->type) {
867 case LDC_CTRL:
868 err = process_control_frame(lp, p);
869 if (err > 0)
870 event_mask |= err;
871 break;
873 case LDC_DATA:
874 event_mask |= LDC_EVENT_DATA_READY;
875 err = 0;
876 break;
878 case LDC_ERR:
879 err = process_error_frame(lp, p);
880 break;
882 default:
883 err = ldc_abort(lp);
884 break;
887 if (err < 0)
888 break;
890 new = lp->rx_head;
891 new += LDC_PACKET_SIZE;
892 if (new == (lp->rx_num_entries * LDC_PACKET_SIZE))
893 new = 0;
894 lp->rx_head = new;
896 err = __set_rx_head(lp, new);
897 if (err < 0) {
898 (void) ldc_abort(lp);
899 break;
901 if (lp->hs_state == LDC_HS_COMPLETE)
902 goto handshake_complete;
905 out:
906 spin_unlock_irqrestore(&lp->lock, flags);
908 send_events(lp, event_mask);
910 return IRQ_HANDLED;
913 static irqreturn_t ldc_tx(int irq, void *dev_id)
915 struct ldc_channel *lp = dev_id;
916 unsigned long flags, orig_state;
917 unsigned int event_mask = 0;
919 spin_lock_irqsave(&lp->lock, flags);
921 orig_state = lp->chan_state;
923 /* We should probably check for hypervisor errors here and
924 * reset the LDC channel if we get one.
926 sun4v_ldc_tx_get_state(lp->id,
927 &lp->tx_head,
928 &lp->tx_tail,
929 &lp->chan_state);
931 ldcdbg(TX, " TX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
932 orig_state, lp->chan_state, lp->tx_head, lp->tx_tail);
934 if (lp->cfg.mode == LDC_MODE_RAW &&
935 lp->chan_state == LDC_CHANNEL_UP) {
936 lp->hs_state = LDC_HS_COMPLETE;
937 ldc_set_state(lp, LDC_STATE_CONNECTED);
939 event_mask |= LDC_EVENT_UP;
942 spin_unlock_irqrestore(&lp->lock, flags);
944 send_events(lp, event_mask);
946 return IRQ_HANDLED;
949 /* XXX ldc_alloc() and ldc_free() needs to run under a mutex so
950 * XXX that addition and removal from the ldc_channel_list has
951 * XXX atomicity, otherwise the __ldc_channel_exists() check is
952 * XXX totally pointless as another thread can slip into ldc_alloc()
953 * XXX and add a channel with the same ID. There also needs to be
954 * XXX a spinlock for ldc_channel_list.
956 static HLIST_HEAD(ldc_channel_list);
958 static int __ldc_channel_exists(unsigned long id)
960 struct ldc_channel *lp;
962 hlist_for_each_entry(lp, &ldc_channel_list, list) {
963 if (lp->id == id)
964 return 1;
966 return 0;
969 static int alloc_queue(const char *name, unsigned long num_entries,
970 struct ldc_packet **base, unsigned long *ra)
972 unsigned long size, order;
973 void *q;
975 size = num_entries * LDC_PACKET_SIZE;
976 order = get_order(size);
978 q = (void *) __get_free_pages(GFP_KERNEL, order);
979 if (!q) {
980 printk(KERN_ERR PFX "Alloc of %s queue failed with "
981 "size=%lu order=%lu\n", name, size, order);
982 return -ENOMEM;
985 memset(q, 0, PAGE_SIZE << order);
987 *base = q;
988 *ra = __pa(q);
990 return 0;
993 static void free_queue(unsigned long num_entries, struct ldc_packet *q)
995 unsigned long size, order;
997 if (!q)
998 return;
1000 size = num_entries * LDC_PACKET_SIZE;
1001 order = get_order(size);
1003 free_pages((unsigned long)q, order);
1006 static unsigned long ldc_cookie_to_index(u64 cookie, void *arg)
1008 u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT;
1009 /* struct ldc_iommu *ldc_iommu = (struct ldc_iommu *)arg; */
1011 cookie &= ~COOKIE_PGSZ_CODE;
1013 return (cookie >> (13ULL + (szcode * 3ULL)));
1016 static void ldc_demap(struct ldc_iommu *iommu, unsigned long id, u64 cookie,
1017 unsigned long entry, unsigned long npages)
1019 struct ldc_mtable_entry *base;
1020 unsigned long i, shift;
1022 shift = (cookie >> COOKIE_PGSZ_CODE_SHIFT) * 3;
1023 base = iommu->page_table + entry;
1024 for (i = 0; i < npages; i++) {
1025 if (base->cookie)
1026 sun4v_ldc_revoke(id, cookie + (i << shift),
1027 base->cookie);
1028 base->mte = 0;
1032 /* XXX Make this configurable... XXX */
1033 #define LDC_IOTABLE_SIZE (8 * 1024)
1035 static int ldc_iommu_init(const char *name, struct ldc_channel *lp)
1037 unsigned long sz, num_tsb_entries, tsbsize, order;
1038 struct ldc_iommu *ldc_iommu = &lp->iommu;
1039 struct iommu_map_table *iommu = &ldc_iommu->iommu_map_table;
1040 struct ldc_mtable_entry *table;
1041 unsigned long hv_err;
1042 int err;
1044 num_tsb_entries = LDC_IOTABLE_SIZE;
1045 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1046 spin_lock_init(&ldc_iommu->lock);
1048 sz = num_tsb_entries / 8;
1049 sz = (sz + 7UL) & ~7UL;
1050 iommu->map = kzalloc(sz, GFP_KERNEL);
1051 if (!iommu->map) {
1052 printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz);
1053 return -ENOMEM;
1055 iommu_tbl_pool_init(iommu, num_tsb_entries, PAGE_SHIFT,
1056 NULL, false /* no large pool */,
1057 1 /* npools */,
1058 true /* skip span boundary check */);
1060 order = get_order(tsbsize);
1062 table = (struct ldc_mtable_entry *)
1063 __get_free_pages(GFP_KERNEL, order);
1064 err = -ENOMEM;
1065 if (!table) {
1066 printk(KERN_ERR PFX "Alloc of MTE table failed, "
1067 "size=%lu order=%lu\n", tsbsize, order);
1068 goto out_free_map;
1071 memset(table, 0, PAGE_SIZE << order);
1073 ldc_iommu->page_table = table;
1075 hv_err = sun4v_ldc_set_map_table(lp->id, __pa(table),
1076 num_tsb_entries);
1077 err = -EINVAL;
1078 if (hv_err)
1079 goto out_free_table;
1081 return 0;
1083 out_free_table:
1084 free_pages((unsigned long) table, order);
1085 ldc_iommu->page_table = NULL;
1087 out_free_map:
1088 kfree(iommu->map);
1089 iommu->map = NULL;
1091 return err;
1094 static void ldc_iommu_release(struct ldc_channel *lp)
1096 struct ldc_iommu *ldc_iommu = &lp->iommu;
1097 struct iommu_map_table *iommu = &ldc_iommu->iommu_map_table;
1098 unsigned long num_tsb_entries, tsbsize, order;
1100 (void) sun4v_ldc_set_map_table(lp->id, 0, 0);
1102 num_tsb_entries = iommu->poolsize * iommu->nr_pools;
1103 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1104 order = get_order(tsbsize);
1106 free_pages((unsigned long) ldc_iommu->page_table, order);
1107 ldc_iommu->page_table = NULL;
1109 kfree(iommu->map);
1110 iommu->map = NULL;
1113 struct ldc_channel *ldc_alloc(unsigned long id,
1114 const struct ldc_channel_config *cfgp,
1115 void *event_arg,
1116 const char *name)
1118 struct ldc_channel *lp;
1119 const struct ldc_mode_ops *mops;
1120 unsigned long dummy1, dummy2, hv_err;
1121 u8 mss, *mssbuf;
1122 int err;
1124 err = -ENODEV;
1125 if (!ldom_domaining_enabled)
1126 goto out_err;
1128 err = -EINVAL;
1129 if (!cfgp)
1130 goto out_err;
1131 if (!name)
1132 goto out_err;
1134 switch (cfgp->mode) {
1135 case LDC_MODE_RAW:
1136 mops = &raw_ops;
1137 mss = LDC_PACKET_SIZE;
1138 break;
1140 case LDC_MODE_UNRELIABLE:
1141 mops = &nonraw_ops;
1142 mss = LDC_PACKET_SIZE - 8;
1143 break;
1145 case LDC_MODE_STREAM:
1146 mops = &stream_ops;
1147 mss = LDC_PACKET_SIZE - 8 - 8;
1148 break;
1150 default:
1151 goto out_err;
1154 if (!cfgp->event || !event_arg || !cfgp->rx_irq || !cfgp->tx_irq)
1155 goto out_err;
1157 hv_err = sun4v_ldc_tx_qinfo(id, &dummy1, &dummy2);
1158 err = -ENODEV;
1159 if (hv_err == HV_ECHANNEL)
1160 goto out_err;
1162 err = -EEXIST;
1163 if (__ldc_channel_exists(id))
1164 goto out_err;
1166 mssbuf = NULL;
1168 lp = kzalloc(sizeof(*lp), GFP_KERNEL);
1169 err = -ENOMEM;
1170 if (!lp)
1171 goto out_err;
1173 spin_lock_init(&lp->lock);
1175 lp->id = id;
1177 err = ldc_iommu_init(name, lp);
1178 if (err)
1179 goto out_free_ldc;
1181 lp->mops = mops;
1182 lp->mss = mss;
1184 lp->cfg = *cfgp;
1185 if (!lp->cfg.mtu)
1186 lp->cfg.mtu = LDC_DEFAULT_MTU;
1188 if (lp->cfg.mode == LDC_MODE_STREAM) {
1189 mssbuf = kzalloc(lp->cfg.mtu, GFP_KERNEL);
1190 if (!mssbuf) {
1191 err = -ENOMEM;
1192 goto out_free_iommu;
1194 lp->mssbuf = mssbuf;
1197 lp->event_arg = event_arg;
1199 /* XXX allow setting via ldc_channel_config to override defaults
1200 * XXX or use some formula based upon mtu
1202 lp->tx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1203 lp->rx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1205 err = alloc_queue("TX", lp->tx_num_entries,
1206 &lp->tx_base, &lp->tx_ra);
1207 if (err)
1208 goto out_free_mssbuf;
1210 err = alloc_queue("RX", lp->rx_num_entries,
1211 &lp->rx_base, &lp->rx_ra);
1212 if (err)
1213 goto out_free_txq;
1215 lp->flags |= LDC_FLAG_ALLOCED_QUEUES;
1217 lp->hs_state = LDC_HS_CLOSED;
1218 ldc_set_state(lp, LDC_STATE_INIT);
1220 INIT_HLIST_NODE(&lp->list);
1221 hlist_add_head(&lp->list, &ldc_channel_list);
1223 INIT_HLIST_HEAD(&lp->mh_list);
1225 snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name);
1226 snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name);
1228 err = request_irq(lp->cfg.rx_irq, ldc_rx, 0,
1229 lp->rx_irq_name, lp);
1230 if (err)
1231 goto out_free_txq;
1233 err = request_irq(lp->cfg.tx_irq, ldc_tx, 0,
1234 lp->tx_irq_name, lp);
1235 if (err) {
1236 free_irq(lp->cfg.rx_irq, lp);
1237 goto out_free_txq;
1240 return lp;
1242 out_free_txq:
1243 free_queue(lp->tx_num_entries, lp->tx_base);
1245 out_free_mssbuf:
1246 kfree(mssbuf);
1248 out_free_iommu:
1249 ldc_iommu_release(lp);
1251 out_free_ldc:
1252 kfree(lp);
1254 out_err:
1255 return ERR_PTR(err);
1257 EXPORT_SYMBOL(ldc_alloc);
1259 void ldc_unbind(struct ldc_channel *lp)
1261 if (lp->flags & LDC_FLAG_REGISTERED_IRQS) {
1262 free_irq(lp->cfg.rx_irq, lp);
1263 free_irq(lp->cfg.tx_irq, lp);
1264 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
1267 if (lp->flags & LDC_FLAG_REGISTERED_QUEUES) {
1268 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1269 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1270 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1272 if (lp->flags & LDC_FLAG_ALLOCED_QUEUES) {
1273 free_queue(lp->tx_num_entries, lp->tx_base);
1274 free_queue(lp->rx_num_entries, lp->rx_base);
1275 lp->flags &= ~LDC_FLAG_ALLOCED_QUEUES;
1278 ldc_set_state(lp, LDC_STATE_INIT);
1280 EXPORT_SYMBOL(ldc_unbind);
1282 void ldc_free(struct ldc_channel *lp)
1284 ldc_unbind(lp);
1285 hlist_del(&lp->list);
1286 kfree(lp->mssbuf);
1287 ldc_iommu_release(lp);
1289 kfree(lp);
1291 EXPORT_SYMBOL(ldc_free);
1293 /* Bind the channel. This registers the LDC queues with
1294 * the hypervisor and puts the channel into a pseudo-listening
1295 * state. This does not initiate a handshake, ldc_connect() does
1296 * that.
1298 int ldc_bind(struct ldc_channel *lp)
1300 unsigned long hv_err, flags;
1301 int err = -EINVAL;
1303 if (lp->state != LDC_STATE_INIT)
1304 return -EINVAL;
1306 spin_lock_irqsave(&lp->lock, flags);
1308 enable_irq(lp->cfg.rx_irq);
1309 enable_irq(lp->cfg.tx_irq);
1311 lp->flags |= LDC_FLAG_REGISTERED_IRQS;
1313 err = -ENODEV;
1314 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1315 if (hv_err)
1316 goto out_free_irqs;
1318 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1319 if (hv_err)
1320 goto out_free_irqs;
1322 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1323 if (hv_err)
1324 goto out_unmap_tx;
1326 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1327 if (hv_err)
1328 goto out_unmap_tx;
1330 lp->flags |= LDC_FLAG_REGISTERED_QUEUES;
1332 hv_err = sun4v_ldc_tx_get_state(lp->id,
1333 &lp->tx_head,
1334 &lp->tx_tail,
1335 &lp->chan_state);
1336 err = -EBUSY;
1337 if (hv_err)
1338 goto out_unmap_rx;
1340 lp->tx_acked = lp->tx_head;
1342 lp->hs_state = LDC_HS_OPEN;
1343 ldc_set_state(lp, LDC_STATE_BOUND);
1345 spin_unlock_irqrestore(&lp->lock, flags);
1347 return 0;
1349 out_unmap_rx:
1350 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1351 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1353 out_unmap_tx:
1354 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1356 out_free_irqs:
1357 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
1358 free_irq(lp->cfg.tx_irq, lp);
1359 free_irq(lp->cfg.rx_irq, lp);
1361 spin_unlock_irqrestore(&lp->lock, flags);
1363 return err;
1365 EXPORT_SYMBOL(ldc_bind);
1367 int ldc_connect(struct ldc_channel *lp)
1369 unsigned long flags;
1370 int err;
1372 if (lp->cfg.mode == LDC_MODE_RAW)
1373 return -EINVAL;
1375 spin_lock_irqsave(&lp->lock, flags);
1377 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1378 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES) ||
1379 lp->hs_state != LDC_HS_OPEN)
1380 err = ((lp->hs_state > LDC_HS_OPEN) ? 0 : -EINVAL);
1381 else
1382 err = start_handshake(lp);
1384 spin_unlock_irqrestore(&lp->lock, flags);
1386 return err;
1388 EXPORT_SYMBOL(ldc_connect);
1390 int ldc_disconnect(struct ldc_channel *lp)
1392 unsigned long hv_err, flags;
1393 int err;
1395 if (lp->cfg.mode == LDC_MODE_RAW)
1396 return -EINVAL;
1398 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1399 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES))
1400 return -EINVAL;
1402 spin_lock_irqsave(&lp->lock, flags);
1404 err = -ENODEV;
1405 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1406 if (hv_err)
1407 goto out_err;
1409 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1410 if (hv_err)
1411 goto out_err;
1413 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1414 if (hv_err)
1415 goto out_err;
1417 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1418 if (hv_err)
1419 goto out_err;
1421 ldc_set_state(lp, LDC_STATE_BOUND);
1422 lp->hs_state = LDC_HS_OPEN;
1423 lp->flags |= LDC_FLAG_RESET;
1425 spin_unlock_irqrestore(&lp->lock, flags);
1427 return 0;
1429 out_err:
1430 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1431 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1432 free_irq(lp->cfg.tx_irq, lp);
1433 free_irq(lp->cfg.rx_irq, lp);
1434 lp->flags &= ~(LDC_FLAG_REGISTERED_IRQS |
1435 LDC_FLAG_REGISTERED_QUEUES);
1436 ldc_set_state(lp, LDC_STATE_INIT);
1438 spin_unlock_irqrestore(&lp->lock, flags);
1440 return err;
1442 EXPORT_SYMBOL(ldc_disconnect);
1444 int ldc_state(struct ldc_channel *lp)
1446 return lp->state;
1448 EXPORT_SYMBOL(ldc_state);
1450 static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size)
1452 struct ldc_packet *p;
1453 unsigned long new_tail;
1454 int err;
1456 if (size > LDC_PACKET_SIZE)
1457 return -EMSGSIZE;
1459 p = data_get_tx_packet(lp, &new_tail);
1460 if (!p)
1461 return -EAGAIN;
1463 memcpy(p, buf, size);
1465 err = send_tx_packet(lp, p, new_tail);
1466 if (!err)
1467 err = size;
1469 return err;
1472 static int read_raw(struct ldc_channel *lp, void *buf, unsigned int size)
1474 struct ldc_packet *p;
1475 unsigned long hv_err, new;
1476 int err;
1478 if (size < LDC_PACKET_SIZE)
1479 return -EINVAL;
1481 hv_err = sun4v_ldc_rx_get_state(lp->id,
1482 &lp->rx_head,
1483 &lp->rx_tail,
1484 &lp->chan_state);
1485 if (hv_err)
1486 return ldc_abort(lp);
1488 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1489 lp->chan_state == LDC_CHANNEL_RESETTING)
1490 return -ECONNRESET;
1492 if (lp->rx_head == lp->rx_tail)
1493 return 0;
1495 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
1496 memcpy(buf, p, LDC_PACKET_SIZE);
1498 new = rx_advance(lp, lp->rx_head);
1499 lp->rx_head = new;
1501 err = __set_rx_head(lp, new);
1502 if (err < 0)
1503 err = -ECONNRESET;
1504 else
1505 err = LDC_PACKET_SIZE;
1507 return err;
1510 static const struct ldc_mode_ops raw_ops = {
1511 .write = write_raw,
1512 .read = read_raw,
1515 static int write_nonraw(struct ldc_channel *lp, const void *buf,
1516 unsigned int size)
1518 unsigned long hv_err, tail;
1519 unsigned int copied;
1520 u32 seq;
1521 int err;
1523 hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail,
1524 &lp->chan_state);
1525 if (unlikely(hv_err))
1526 return -EBUSY;
1528 if (unlikely(lp->chan_state != LDC_CHANNEL_UP))
1529 return ldc_abort(lp);
1531 if (!tx_has_space_for(lp, size))
1532 return -EAGAIN;
1534 seq = lp->snd_nxt;
1535 copied = 0;
1536 tail = lp->tx_tail;
1537 while (copied < size) {
1538 struct ldc_packet *p = lp->tx_base + (tail / LDC_PACKET_SIZE);
1539 u8 *data = ((lp->cfg.mode == LDC_MODE_UNRELIABLE) ?
1540 p->u.u_data :
1541 p->u.r.r_data);
1542 int data_len;
1544 p->type = LDC_DATA;
1545 p->stype = LDC_INFO;
1546 p->ctrl = 0;
1548 data_len = size - copied;
1549 if (data_len > lp->mss)
1550 data_len = lp->mss;
1552 BUG_ON(data_len > LDC_LEN);
1554 p->env = (data_len |
1555 (copied == 0 ? LDC_START : 0) |
1556 (data_len == size - copied ? LDC_STOP : 0));
1558 p->seqid = ++seq;
1560 ldcdbg(DATA, "SENT DATA [%02x:%02x:%02x:%02x:%08x]\n",
1561 p->type,
1562 p->stype,
1563 p->ctrl,
1564 p->env,
1565 p->seqid);
1567 memcpy(data, buf, data_len);
1568 buf += data_len;
1569 copied += data_len;
1571 tail = tx_advance(lp, tail);
1574 err = set_tx_tail(lp, tail);
1575 if (!err) {
1576 lp->snd_nxt = seq;
1577 err = size;
1580 return err;
1583 static int rx_bad_seq(struct ldc_channel *lp, struct ldc_packet *p,
1584 struct ldc_packet *first_frag)
1586 int err;
1588 if (first_frag)
1589 lp->rcv_nxt = first_frag->seqid - 1;
1591 err = send_data_nack(lp, p);
1592 if (err)
1593 return err;
1595 err = __set_rx_head(lp, lp->rx_tail);
1596 if (err < 0)
1597 return ldc_abort(lp);
1599 return 0;
1602 static int data_ack_nack(struct ldc_channel *lp, struct ldc_packet *p)
1604 if (p->stype & LDC_ACK) {
1605 int err = process_data_ack(lp, p);
1606 if (err)
1607 return err;
1609 if (p->stype & LDC_NACK)
1610 return ldc_abort(lp);
1612 return 0;
1615 static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head)
1617 unsigned long dummy;
1618 int limit = 1000;
1620 ldcdbg(DATA, "DATA WAIT cur_head[%lx] rx_head[%lx] rx_tail[%lx]\n",
1621 cur_head, lp->rx_head, lp->rx_tail);
1622 while (limit-- > 0) {
1623 unsigned long hv_err;
1625 hv_err = sun4v_ldc_rx_get_state(lp->id,
1626 &dummy,
1627 &lp->rx_tail,
1628 &lp->chan_state);
1629 if (hv_err)
1630 return ldc_abort(lp);
1632 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1633 lp->chan_state == LDC_CHANNEL_RESETTING)
1634 return -ECONNRESET;
1636 if (cur_head != lp->rx_tail) {
1637 ldcdbg(DATA, "DATA WAIT DONE "
1638 "head[%lx] tail[%lx] chan_state[%lx]\n",
1639 dummy, lp->rx_tail, lp->chan_state);
1640 return 0;
1643 udelay(1);
1645 return -EAGAIN;
1648 static int rx_set_head(struct ldc_channel *lp, unsigned long head)
1650 int err = __set_rx_head(lp, head);
1652 if (err < 0)
1653 return ldc_abort(lp);
1655 lp->rx_head = head;
1656 return 0;
1659 static void send_data_ack(struct ldc_channel *lp)
1661 unsigned long new_tail;
1662 struct ldc_packet *p;
1664 p = data_get_tx_packet(lp, &new_tail);
1665 if (likely(p)) {
1666 int err;
1668 memset(p, 0, sizeof(*p));
1669 p->type = LDC_DATA;
1670 p->stype = LDC_ACK;
1671 p->ctrl = 0;
1672 p->seqid = lp->snd_nxt + 1;
1673 p->u.r.ackid = lp->rcv_nxt;
1675 err = send_tx_packet(lp, p, new_tail);
1676 if (!err)
1677 lp->snd_nxt++;
1681 static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
1683 struct ldc_packet *first_frag;
1684 unsigned long hv_err, new;
1685 int err, copied;
1687 hv_err = sun4v_ldc_rx_get_state(lp->id,
1688 &lp->rx_head,
1689 &lp->rx_tail,
1690 &lp->chan_state);
1691 if (hv_err)
1692 return ldc_abort(lp);
1694 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1695 lp->chan_state == LDC_CHANNEL_RESETTING)
1696 return -ECONNRESET;
1698 if (lp->rx_head == lp->rx_tail)
1699 return 0;
1701 first_frag = NULL;
1702 copied = err = 0;
1703 new = lp->rx_head;
1704 while (1) {
1705 struct ldc_packet *p;
1706 int pkt_len;
1708 BUG_ON(new == lp->rx_tail);
1709 p = lp->rx_base + (new / LDC_PACKET_SIZE);
1711 ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x:%08x] "
1712 "rcv_nxt[%08x]\n",
1713 p->type,
1714 p->stype,
1715 p->ctrl,
1716 p->env,
1717 p->seqid,
1718 p->u.r.ackid,
1719 lp->rcv_nxt);
1721 if (unlikely(!rx_seq_ok(lp, p->seqid))) {
1722 err = rx_bad_seq(lp, p, first_frag);
1723 copied = 0;
1724 break;
1727 if (p->type & LDC_CTRL) {
1728 err = process_control_frame(lp, p);
1729 if (err < 0)
1730 break;
1731 err = 0;
1734 lp->rcv_nxt = p->seqid;
1737 * If this is a control-only packet, there is nothing
1738 * else to do but advance the rx queue since the packet
1739 * was already processed above.
1741 if (!(p->type & LDC_DATA)) {
1742 new = rx_advance(lp, new);
1743 break;
1745 if (p->stype & (LDC_ACK | LDC_NACK)) {
1746 err = data_ack_nack(lp, p);
1747 if (err)
1748 break;
1750 if (!(p->stype & LDC_INFO)) {
1751 new = rx_advance(lp, new);
1752 err = rx_set_head(lp, new);
1753 if (err)
1754 break;
1755 goto no_data;
1758 pkt_len = p->env & LDC_LEN;
1760 /* Every initial packet starts with the START bit set.
1762 * Singleton packets will have both START+STOP set.
1764 * Fragments will have START set in the first frame, STOP
1765 * set in the last frame, and neither bit set in middle
1766 * frames of the packet.
1768 * Therefore if we are at the beginning of a packet and
1769 * we don't see START, or we are in the middle of a fragmented
1770 * packet and do see START, we are unsynchronized and should
1771 * flush the RX queue.
1773 if ((first_frag == NULL && !(p->env & LDC_START)) ||
1774 (first_frag != NULL && (p->env & LDC_START))) {
1775 if (!first_frag)
1776 new = rx_advance(lp, new);
1778 err = rx_set_head(lp, new);
1779 if (err)
1780 break;
1782 if (!first_frag)
1783 goto no_data;
1785 if (!first_frag)
1786 first_frag = p;
1788 if (pkt_len > size - copied) {
1789 /* User didn't give us a big enough buffer,
1790 * what to do? This is a pretty serious error.
1792 * Since we haven't updated the RX ring head to
1793 * consume any of the packets, signal the error
1794 * to the user and just leave the RX ring alone.
1796 * This seems the best behavior because this allows
1797 * a user of the LDC layer to start with a small
1798 * RX buffer for ldc_read() calls and use -EMSGSIZE
1799 * as a cue to enlarge it's read buffer.
1801 err = -EMSGSIZE;
1802 break;
1805 /* Ok, we are gonna eat this one. */
1806 new = rx_advance(lp, new);
1808 memcpy(buf,
1809 (lp->cfg.mode == LDC_MODE_UNRELIABLE ?
1810 p->u.u_data : p->u.r.r_data), pkt_len);
1811 buf += pkt_len;
1812 copied += pkt_len;
1814 if (p->env & LDC_STOP)
1815 break;
1817 no_data:
1818 if (new == lp->rx_tail) {
1819 err = rx_data_wait(lp, new);
1820 if (err)
1821 break;
1825 if (!err)
1826 err = rx_set_head(lp, new);
1828 if (err && first_frag)
1829 lp->rcv_nxt = first_frag->seqid - 1;
1831 if (!err) {
1832 err = copied;
1833 if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE)
1834 send_data_ack(lp);
1837 return err;
1840 static const struct ldc_mode_ops nonraw_ops = {
1841 .write = write_nonraw,
1842 .read = read_nonraw,
1845 static int write_stream(struct ldc_channel *lp, const void *buf,
1846 unsigned int size)
1848 if (size > lp->cfg.mtu)
1849 size = lp->cfg.mtu;
1850 return write_nonraw(lp, buf, size);
1853 static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size)
1855 if (!lp->mssbuf_len) {
1856 int err = read_nonraw(lp, lp->mssbuf, lp->cfg.mtu);
1857 if (err < 0)
1858 return err;
1860 lp->mssbuf_len = err;
1861 lp->mssbuf_off = 0;
1864 if (size > lp->mssbuf_len)
1865 size = lp->mssbuf_len;
1866 memcpy(buf, lp->mssbuf + lp->mssbuf_off, size);
1868 lp->mssbuf_off += size;
1869 lp->mssbuf_len -= size;
1871 return size;
1874 static const struct ldc_mode_ops stream_ops = {
1875 .write = write_stream,
1876 .read = read_stream,
1879 int ldc_write(struct ldc_channel *lp, const void *buf, unsigned int size)
1881 unsigned long flags;
1882 int err;
1884 if (!buf)
1885 return -EINVAL;
1887 if (!size)
1888 return 0;
1890 spin_lock_irqsave(&lp->lock, flags);
1892 if (lp->hs_state != LDC_HS_COMPLETE)
1893 err = -ENOTCONN;
1894 else
1895 err = lp->mops->write(lp, buf, size);
1897 spin_unlock_irqrestore(&lp->lock, flags);
1899 return err;
1901 EXPORT_SYMBOL(ldc_write);
1903 int ldc_read(struct ldc_channel *lp, void *buf, unsigned int size)
1905 unsigned long flags;
1906 int err;
1908 if (!buf)
1909 return -EINVAL;
1911 if (!size)
1912 return 0;
1914 spin_lock_irqsave(&lp->lock, flags);
1916 if (lp->hs_state != LDC_HS_COMPLETE)
1917 err = -ENOTCONN;
1918 else
1919 err = lp->mops->read(lp, buf, size);
1921 spin_unlock_irqrestore(&lp->lock, flags);
1923 return err;
1925 EXPORT_SYMBOL(ldc_read);
1927 static u64 pagesize_code(void)
1929 switch (PAGE_SIZE) {
1930 default:
1931 case (8ULL * 1024ULL):
1932 return 0;
1933 case (64ULL * 1024ULL):
1934 return 1;
1935 case (512ULL * 1024ULL):
1936 return 2;
1937 case (4ULL * 1024ULL * 1024ULL):
1938 return 3;
1939 case (32ULL * 1024ULL * 1024ULL):
1940 return 4;
1941 case (256ULL * 1024ULL * 1024ULL):
1942 return 5;
1946 static u64 make_cookie(u64 index, u64 pgsz_code, u64 page_offset)
1948 return ((pgsz_code << COOKIE_PGSZ_CODE_SHIFT) |
1949 (index << PAGE_SHIFT) |
1950 page_offset);
1954 static struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu,
1955 unsigned long npages)
1957 long entry;
1959 entry = iommu_tbl_range_alloc(NULL, &iommu->iommu_map_table,
1960 npages, NULL, (unsigned long)-1, 0);
1961 if (unlikely(entry == IOMMU_ERROR_CODE))
1962 return NULL;
1964 return iommu->page_table + entry;
1967 static u64 perm_to_mte(unsigned int map_perm)
1969 u64 mte_base;
1971 mte_base = pagesize_code();
1973 if (map_perm & LDC_MAP_SHADOW) {
1974 if (map_perm & LDC_MAP_R)
1975 mte_base |= LDC_MTE_COPY_R;
1976 if (map_perm & LDC_MAP_W)
1977 mte_base |= LDC_MTE_COPY_W;
1979 if (map_perm & LDC_MAP_DIRECT) {
1980 if (map_perm & LDC_MAP_R)
1981 mte_base |= LDC_MTE_READ;
1982 if (map_perm & LDC_MAP_W)
1983 mte_base |= LDC_MTE_WRITE;
1984 if (map_perm & LDC_MAP_X)
1985 mte_base |= LDC_MTE_EXEC;
1987 if (map_perm & LDC_MAP_IO) {
1988 if (map_perm & LDC_MAP_R)
1989 mte_base |= LDC_MTE_IOMMU_R;
1990 if (map_perm & LDC_MAP_W)
1991 mte_base |= LDC_MTE_IOMMU_W;
1994 return mte_base;
1997 static int pages_in_region(unsigned long base, long len)
1999 int count = 0;
2001 do {
2002 unsigned long new = (base + PAGE_SIZE) & PAGE_MASK;
2004 len -= (new - base);
2005 base = new;
2006 count++;
2007 } while (len > 0);
2009 return count;
2012 struct cookie_state {
2013 struct ldc_mtable_entry *page_table;
2014 struct ldc_trans_cookie *cookies;
2015 u64 mte_base;
2016 u64 prev_cookie;
2017 u32 pte_idx;
2018 u32 nc;
2021 static void fill_cookies(struct cookie_state *sp, unsigned long pa,
2022 unsigned long off, unsigned long len)
2024 do {
2025 unsigned long tlen, new = pa + PAGE_SIZE;
2026 u64 this_cookie;
2028 sp->page_table[sp->pte_idx].mte = sp->mte_base | pa;
2030 tlen = PAGE_SIZE;
2031 if (off)
2032 tlen = PAGE_SIZE - off;
2033 if (tlen > len)
2034 tlen = len;
2036 this_cookie = make_cookie(sp->pte_idx,
2037 pagesize_code(), off);
2039 off = 0;
2041 if (this_cookie == sp->prev_cookie) {
2042 sp->cookies[sp->nc - 1].cookie_size += tlen;
2043 } else {
2044 sp->cookies[sp->nc].cookie_addr = this_cookie;
2045 sp->cookies[sp->nc].cookie_size = tlen;
2046 sp->nc++;
2048 sp->prev_cookie = this_cookie + tlen;
2050 sp->pte_idx++;
2052 len -= tlen;
2053 pa = new;
2054 } while (len > 0);
2057 static int sg_count_one(struct scatterlist *sg)
2059 unsigned long base = page_to_pfn(sg_page(sg)) << PAGE_SHIFT;
2060 long len = sg->length;
2062 if ((sg->offset | len) & (8UL - 1))
2063 return -EFAULT;
2065 return pages_in_region(base + sg->offset, len);
2068 static int sg_count_pages(struct scatterlist *sg, int num_sg)
2070 int count;
2071 int i;
2073 count = 0;
2074 for (i = 0; i < num_sg; i++) {
2075 int err = sg_count_one(sg + i);
2076 if (err < 0)
2077 return err;
2078 count += err;
2081 return count;
2084 int ldc_map_sg(struct ldc_channel *lp,
2085 struct scatterlist *sg, int num_sg,
2086 struct ldc_trans_cookie *cookies, int ncookies,
2087 unsigned int map_perm)
2089 unsigned long i, npages;
2090 struct ldc_mtable_entry *base;
2091 struct cookie_state state;
2092 struct ldc_iommu *iommu;
2093 int err;
2094 struct scatterlist *s;
2096 if (map_perm & ~LDC_MAP_ALL)
2097 return -EINVAL;
2099 err = sg_count_pages(sg, num_sg);
2100 if (err < 0)
2101 return err;
2103 npages = err;
2104 if (err > ncookies)
2105 return -EMSGSIZE;
2107 iommu = &lp->iommu;
2109 base = alloc_npages(iommu, npages);
2111 if (!base)
2112 return -ENOMEM;
2114 state.page_table = iommu->page_table;
2115 state.cookies = cookies;
2116 state.mte_base = perm_to_mte(map_perm);
2117 state.prev_cookie = ~(u64)0;
2118 state.pte_idx = (base - iommu->page_table);
2119 state.nc = 0;
2121 for_each_sg(sg, s, num_sg, i) {
2122 fill_cookies(&state, page_to_pfn(sg_page(s)) << PAGE_SHIFT,
2123 s->offset, s->length);
2126 return state.nc;
2128 EXPORT_SYMBOL(ldc_map_sg);
2130 int ldc_map_single(struct ldc_channel *lp,
2131 void *buf, unsigned int len,
2132 struct ldc_trans_cookie *cookies, int ncookies,
2133 unsigned int map_perm)
2135 unsigned long npages, pa;
2136 struct ldc_mtable_entry *base;
2137 struct cookie_state state;
2138 struct ldc_iommu *iommu;
2140 if ((map_perm & ~LDC_MAP_ALL) || (ncookies < 1))
2141 return -EINVAL;
2143 pa = __pa(buf);
2144 if ((pa | len) & (8UL - 1))
2145 return -EFAULT;
2147 npages = pages_in_region(pa, len);
2149 iommu = &lp->iommu;
2151 base = alloc_npages(iommu, npages);
2153 if (!base)
2154 return -ENOMEM;
2156 state.page_table = iommu->page_table;
2157 state.cookies = cookies;
2158 state.mte_base = perm_to_mte(map_perm);
2159 state.prev_cookie = ~(u64)0;
2160 state.pte_idx = (base - iommu->page_table);
2161 state.nc = 0;
2162 fill_cookies(&state, (pa & PAGE_MASK), (pa & ~PAGE_MASK), len);
2163 BUG_ON(state.nc > ncookies);
2165 return state.nc;
2167 EXPORT_SYMBOL(ldc_map_single);
2170 static void free_npages(unsigned long id, struct ldc_iommu *iommu,
2171 u64 cookie, u64 size)
2173 unsigned long npages, entry;
2175 npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT;
2177 entry = ldc_cookie_to_index(cookie, iommu);
2178 ldc_demap(iommu, id, cookie, entry, npages);
2179 iommu_tbl_range_free(&iommu->iommu_map_table, cookie, npages, entry);
2182 void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies,
2183 int ncookies)
2185 struct ldc_iommu *iommu = &lp->iommu;
2186 int i;
2187 unsigned long flags;
2189 spin_lock_irqsave(&iommu->lock, flags);
2190 for (i = 0; i < ncookies; i++) {
2191 u64 addr = cookies[i].cookie_addr;
2192 u64 size = cookies[i].cookie_size;
2194 free_npages(lp->id, iommu, addr, size);
2196 spin_unlock_irqrestore(&iommu->lock, flags);
2198 EXPORT_SYMBOL(ldc_unmap);
2200 int ldc_copy(struct ldc_channel *lp, int copy_dir,
2201 void *buf, unsigned int len, unsigned long offset,
2202 struct ldc_trans_cookie *cookies, int ncookies)
2204 unsigned int orig_len;
2205 unsigned long ra;
2206 int i;
2208 if (copy_dir != LDC_COPY_IN && copy_dir != LDC_COPY_OUT) {
2209 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Bad copy_dir[%d]\n",
2210 lp->id, copy_dir);
2211 return -EINVAL;
2214 ra = __pa(buf);
2215 if ((ra | len | offset) & (8UL - 1)) {
2216 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Unaligned buffer "
2217 "ra[%lx] len[%x] offset[%lx]\n",
2218 lp->id, ra, len, offset);
2219 return -EFAULT;
2222 if (lp->hs_state != LDC_HS_COMPLETE ||
2223 (lp->flags & LDC_FLAG_RESET)) {
2224 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Link down hs_state[%x] "
2225 "flags[%x]\n", lp->id, lp->hs_state, lp->flags);
2226 return -ECONNRESET;
2229 orig_len = len;
2230 for (i = 0; i < ncookies; i++) {
2231 unsigned long cookie_raddr = cookies[i].cookie_addr;
2232 unsigned long this_len = cookies[i].cookie_size;
2233 unsigned long actual_len;
2235 if (unlikely(offset)) {
2236 unsigned long this_off = offset;
2238 if (this_off > this_len)
2239 this_off = this_len;
2241 offset -= this_off;
2242 this_len -= this_off;
2243 if (!this_len)
2244 continue;
2245 cookie_raddr += this_off;
2248 if (this_len > len)
2249 this_len = len;
2251 while (1) {
2252 unsigned long hv_err;
2254 hv_err = sun4v_ldc_copy(lp->id, copy_dir,
2255 cookie_raddr, ra,
2256 this_len, &actual_len);
2257 if (unlikely(hv_err)) {
2258 printk(KERN_ERR PFX "ldc_copy: ID[%lu] "
2259 "HV error %lu\n",
2260 lp->id, hv_err);
2261 if (lp->hs_state != LDC_HS_COMPLETE ||
2262 (lp->flags & LDC_FLAG_RESET))
2263 return -ECONNRESET;
2264 else
2265 return -EFAULT;
2268 cookie_raddr += actual_len;
2269 ra += actual_len;
2270 len -= actual_len;
2271 if (actual_len == this_len)
2272 break;
2274 this_len -= actual_len;
2277 if (!len)
2278 break;
2281 /* It is caller policy what to do about short copies.
2282 * For example, a networking driver can declare the
2283 * packet a runt and drop it.
2286 return orig_len - len;
2288 EXPORT_SYMBOL(ldc_copy);
2290 void *ldc_alloc_exp_dring(struct ldc_channel *lp, unsigned int len,
2291 struct ldc_trans_cookie *cookies, int *ncookies,
2292 unsigned int map_perm)
2294 void *buf;
2295 int err;
2297 if (len & (8UL - 1))
2298 return ERR_PTR(-EINVAL);
2300 buf = kzalloc(len, GFP_ATOMIC);
2301 if (!buf)
2302 return ERR_PTR(-ENOMEM);
2304 err = ldc_map_single(lp, buf, len, cookies, *ncookies, map_perm);
2305 if (err < 0) {
2306 kfree(buf);
2307 return ERR_PTR(err);
2309 *ncookies = err;
2311 return buf;
2313 EXPORT_SYMBOL(ldc_alloc_exp_dring);
2315 void ldc_free_exp_dring(struct ldc_channel *lp, void *buf, unsigned int len,
2316 struct ldc_trans_cookie *cookies, int ncookies)
2318 ldc_unmap(lp, cookies, ncookies);
2319 kfree(buf);
2321 EXPORT_SYMBOL(ldc_free_exp_dring);
2323 static int __init ldc_init(void)
2325 unsigned long major, minor;
2326 struct mdesc_handle *hp;
2327 const u64 *v;
2328 int err;
2329 u64 mp;
2331 hp = mdesc_grab();
2332 if (!hp)
2333 return -ENODEV;
2335 mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
2336 err = -ENODEV;
2337 if (mp == MDESC_NODE_NULL)
2338 goto out;
2340 v = mdesc_get_property(hp, mp, "domaining-enabled", NULL);
2341 if (!v)
2342 goto out;
2344 major = 1;
2345 minor = 0;
2346 if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) {
2347 printk(KERN_INFO PFX "Could not register LDOM hvapi.\n");
2348 goto out;
2351 printk(KERN_INFO "%s", version);
2353 if (!*v) {
2354 printk(KERN_INFO PFX "Domaining disabled.\n");
2355 goto out;
2357 ldom_domaining_enabled = 1;
2358 err = 0;
2360 out:
2361 mdesc_release(hp);
2362 return err;
2365 core_initcall(ldc_init);