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CRISv32: Remove unnecessary KERN_INFO from sync_serial
[mirror_ubuntu-bionic-kernel.git] / arch / sparc / kernel / ldc.c
1 /* ldc.c: Logical Domain Channel link-layer protocol driver.
2 *
3 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
4 */
5
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
19 #include <asm/hypervisor.h>
20 #include <asm/iommu.h>
21 #include <asm/page.h>
22 #include <asm/ldc.h>
23 #include <asm/mdesc.h>
24
25 #define DRV_MODULE_NAME "ldc"
26 #define PFX DRV_MODULE_NAME ": "
27 #define DRV_MODULE_VERSION "1.1"
28 #define DRV_MODULE_RELDATE "July 22, 2008"
29
30 static char version[] =
31 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
32 #define LDC_PACKET_SIZE 64
33
34 /* Packet header layout for unreliable and reliable mode frames.
35 * When in RAW mode, packets are simply straight 64-byte payloads
36 * with no headers.
37 */
38 struct ldc_packet {
39 u8 type;
40 #define LDC_CTRL 0x01
41 #define LDC_DATA 0x02
42 #define LDC_ERR 0x10
43
44 u8 stype;
45 #define LDC_INFO 0x01
46 #define LDC_ACK 0x02
47 #define LDC_NACK 0x04
48
49 u8 ctrl;
50 #define LDC_VERS 0x01 /* Link Version */
51 #define LDC_RTS 0x02 /* Request To Send */
52 #define LDC_RTR 0x03 /* Ready To Receive */
53 #define LDC_RDX 0x04 /* Ready for Data eXchange */
54 #define LDC_CTRL_MSK 0x0f
55
56 u8 env;
57 #define LDC_LEN 0x3f
58 #define LDC_FRAG_MASK 0xc0
59 #define LDC_START 0x40
60 #define LDC_STOP 0x80
61
62 u32 seqid;
63
64 union {
65 u8 u_data[LDC_PACKET_SIZE - 8];
66 struct {
67 u32 pad;
68 u32 ackid;
69 u8 r_data[LDC_PACKET_SIZE - 8 - 8];
70 } r;
71 } u;
72 };
73
74 struct ldc_version {
75 u16 major;
76 u16 minor;
77 };
78
79 /* Ordered from largest major to lowest. */
80 static struct ldc_version ver_arr[] = {
81 { .major = 1, .minor = 0 },
82 };
83
84 #define LDC_DEFAULT_MTU (4 * LDC_PACKET_SIZE)
85 #define LDC_DEFAULT_NUM_ENTRIES (PAGE_SIZE / LDC_PACKET_SIZE)
86
87 struct ldc_channel;
88
89 struct ldc_mode_ops {
90 int (*write)(struct ldc_channel *, const void *, unsigned int);
91 int (*read)(struct ldc_channel *, void *, unsigned int);
92 };
93
94 static const struct ldc_mode_ops raw_ops;
95 static const struct ldc_mode_ops nonraw_ops;
96 static const struct ldc_mode_ops stream_ops;
97
98 int ldom_domaining_enabled;
99
100 struct ldc_iommu {
101 /* Protects arena alloc/free. */
102 spinlock_t lock;
103 struct iommu_arena arena;
104 struct ldc_mtable_entry *page_table;
105 };
106
107 struct ldc_channel {
108 /* Protects all operations that depend upon channel state. */
109 spinlock_t lock;
110
111 unsigned long id;
112
113 u8 *mssbuf;
114 u32 mssbuf_len;
115 u32 mssbuf_off;
116
117 struct ldc_packet *tx_base;
118 unsigned long tx_head;
119 unsigned long tx_tail;
120 unsigned long tx_num_entries;
121 unsigned long tx_ra;
122
123 unsigned long tx_acked;
124
125 struct ldc_packet *rx_base;
126 unsigned long rx_head;
127 unsigned long rx_tail;
128 unsigned long rx_num_entries;
129 unsigned long rx_ra;
130
131 u32 rcv_nxt;
132 u32 snd_nxt;
133
134 unsigned long chan_state;
135
136 struct ldc_channel_config cfg;
137 void *event_arg;
138
139 const struct ldc_mode_ops *mops;
140
141 struct ldc_iommu iommu;
142
143 struct ldc_version ver;
144
145 u8 hs_state;
146 #define LDC_HS_CLOSED 0x00
147 #define LDC_HS_OPEN 0x01
148 #define LDC_HS_GOTVERS 0x02
149 #define LDC_HS_SENTRTR 0x03
150 #define LDC_HS_GOTRTR 0x04
151 #define LDC_HS_COMPLETE 0x10
152
153 u8 flags;
154 #define LDC_FLAG_ALLOCED_QUEUES 0x01
155 #define LDC_FLAG_REGISTERED_QUEUES 0x02
156 #define LDC_FLAG_REGISTERED_IRQS 0x04
157 #define LDC_FLAG_RESET 0x10
158
159 u8 mss;
160 u8 state;
161
162 #define LDC_IRQ_NAME_MAX 32
163 char rx_irq_name[LDC_IRQ_NAME_MAX];
164 char tx_irq_name[LDC_IRQ_NAME_MAX];
165
166 struct hlist_head mh_list;
167
168 struct hlist_node list;
169 };
170
171 #define ldcdbg(TYPE, f, a...) \
172 do { if (lp->cfg.debug & LDC_DEBUG_##TYPE) \
173 printk(KERN_INFO PFX "ID[%lu] " f, lp->id, ## a); \
174 } while (0)
175
176 static const char *state_to_str(u8 state)
177 {
178 switch (state) {
179 case LDC_STATE_INVALID:
180 return "INVALID";
181 case LDC_STATE_INIT:
182 return "INIT";
183 case LDC_STATE_BOUND:
184 return "BOUND";
185 case LDC_STATE_READY:
186 return "READY";
187 case LDC_STATE_CONNECTED:
188 return "CONNECTED";
189 default:
190 return "<UNKNOWN>";
191 }
192 }
193
194 static void ldc_set_state(struct ldc_channel *lp, u8 state)
195 {
196 ldcdbg(STATE, "STATE (%s) --> (%s)\n",
197 state_to_str(lp->state),
198 state_to_str(state));
199
200 lp->state = state;
201 }
202
203 static unsigned long __advance(unsigned long off, unsigned long num_entries)
204 {
205 off += LDC_PACKET_SIZE;
206 if (off == (num_entries * LDC_PACKET_SIZE))
207 off = 0;
208
209 return off;
210 }
211
212 static unsigned long rx_advance(struct ldc_channel *lp, unsigned long off)
213 {
214 return __advance(off, lp->rx_num_entries);
215 }
216
217 static unsigned long tx_advance(struct ldc_channel *lp, unsigned long off)
218 {
219 return __advance(off, lp->tx_num_entries);
220 }
221
222 static struct ldc_packet *handshake_get_tx_packet(struct ldc_channel *lp,
223 unsigned long *new_tail)
224 {
225 struct ldc_packet *p;
226 unsigned long t;
227
228 t = tx_advance(lp, lp->tx_tail);
229 if (t == lp->tx_head)
230 return NULL;
231
232 *new_tail = t;
233
234 p = lp->tx_base;
235 return p + (lp->tx_tail / LDC_PACKET_SIZE);
236 }
237
238 /* When we are in reliable or stream mode, have to track the next packet
239 * we haven't gotten an ACK for in the TX queue using tx_acked. We have
240 * to be careful not to stomp over the queue past that point. During
241 * the handshake, we don't have TX data packets pending in the queue
242 * and that's why handshake_get_tx_packet() need not be mindful of
243 * lp->tx_acked.
244 */
245 static unsigned long head_for_data(struct ldc_channel *lp)
246 {
247 if (lp->cfg.mode == LDC_MODE_STREAM)
248 return lp->tx_acked;
249 return lp->tx_head;
250 }
251
252 static int tx_has_space_for(struct ldc_channel *lp, unsigned int size)
253 {
254 unsigned long limit, tail, new_tail, diff;
255 unsigned int mss;
256
257 limit = head_for_data(lp);
258 tail = lp->tx_tail;
259 new_tail = tx_advance(lp, tail);
260 if (new_tail == limit)
261 return 0;
262
263 if (limit > new_tail)
264 diff = limit - new_tail;
265 else
266 diff = (limit +
267 ((lp->tx_num_entries * LDC_PACKET_SIZE) - new_tail));
268 diff /= LDC_PACKET_SIZE;
269 mss = lp->mss;
270
271 if (diff * mss < size)
272 return 0;
273
274 return 1;
275 }
276
277 static struct ldc_packet *data_get_tx_packet(struct ldc_channel *lp,
278 unsigned long *new_tail)
279 {
280 struct ldc_packet *p;
281 unsigned long h, t;
282
283 h = head_for_data(lp);
284 t = tx_advance(lp, lp->tx_tail);
285 if (t == h)
286 return NULL;
287
288 *new_tail = t;
289
290 p = lp->tx_base;
291 return p + (lp->tx_tail / LDC_PACKET_SIZE);
292 }
293
294 static int set_tx_tail(struct ldc_channel *lp, unsigned long tail)
295 {
296 unsigned long orig_tail = lp->tx_tail;
297 int limit = 1000;
298
299 lp->tx_tail = tail;
300 while (limit-- > 0) {
301 unsigned long err;
302
303 err = sun4v_ldc_tx_set_qtail(lp->id, tail);
304 if (!err)
305 return 0;
306
307 if (err != HV_EWOULDBLOCK) {
308 lp->tx_tail = orig_tail;
309 return -EINVAL;
310 }
311 udelay(1);
312 }
313
314 lp->tx_tail = orig_tail;
315 return -EBUSY;
316 }
317
318 /* This just updates the head value in the hypervisor using
319 * a polling loop with a timeout. The caller takes care of
320 * upating software state representing the head change, if any.
321 */
322 static int __set_rx_head(struct ldc_channel *lp, unsigned long head)
323 {
324 int limit = 1000;
325
326 while (limit-- > 0) {
327 unsigned long err;
328
329 err = sun4v_ldc_rx_set_qhead(lp->id, head);
330 if (!err)
331 return 0;
332
333 if (err != HV_EWOULDBLOCK)
334 return -EINVAL;
335
336 udelay(1);
337 }
338
339 return -EBUSY;
340 }
341
342 static int send_tx_packet(struct ldc_channel *lp,
343 struct ldc_packet *p,
344 unsigned long new_tail)
345 {
346 BUG_ON(p != (lp->tx_base + (lp->tx_tail / LDC_PACKET_SIZE)));
347
348 return set_tx_tail(lp, new_tail);
349 }
350
351 static struct ldc_packet *handshake_compose_ctrl(struct ldc_channel *lp,
352 u8 stype, u8 ctrl,
353 void *data, int dlen,
354 unsigned long *new_tail)
355 {
356 struct ldc_packet *p = handshake_get_tx_packet(lp, new_tail);
357
358 if (p) {
359 memset(p, 0, sizeof(*p));
360 p->type = LDC_CTRL;
361 p->stype = stype;
362 p->ctrl = ctrl;
363 if (data)
364 memcpy(p->u.u_data, data, dlen);
365 }
366 return p;
367 }
368
369 static int start_handshake(struct ldc_channel *lp)
370 {
371 struct ldc_packet *p;
372 struct ldc_version *ver;
373 unsigned long new_tail;
374
375 ver = &ver_arr[0];
376
377 ldcdbg(HS, "SEND VER INFO maj[%u] min[%u]\n",
378 ver->major, ver->minor);
379
380 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
381 ver, sizeof(*ver), &new_tail);
382 if (p) {
383 int err = send_tx_packet(lp, p, new_tail);
384 if (!err)
385 lp->flags &= ~LDC_FLAG_RESET;
386 return err;
387 }
388 return -EBUSY;
389 }
390
391 static int send_version_nack(struct ldc_channel *lp,
392 u16 major, u16 minor)
393 {
394 struct ldc_packet *p;
395 struct ldc_version ver;
396 unsigned long new_tail;
397
398 ver.major = major;
399 ver.minor = minor;
400
401 p = handshake_compose_ctrl(lp, LDC_NACK, LDC_VERS,
402 &ver, sizeof(ver), &new_tail);
403 if (p) {
404 ldcdbg(HS, "SEND VER NACK maj[%u] min[%u]\n",
405 ver.major, ver.minor);
406
407 return send_tx_packet(lp, p, new_tail);
408 }
409 return -EBUSY;
410 }
411
412 static int send_version_ack(struct ldc_channel *lp,
413 struct ldc_version *vp)
414 {
415 struct ldc_packet *p;
416 unsigned long new_tail;
417
418 p = handshake_compose_ctrl(lp, LDC_ACK, LDC_VERS,
419 vp, sizeof(*vp), &new_tail);
420 if (p) {
421 ldcdbg(HS, "SEND VER ACK maj[%u] min[%u]\n",
422 vp->major, vp->minor);
423
424 return send_tx_packet(lp, p, new_tail);
425 }
426 return -EBUSY;
427 }
428
429 static int send_rts(struct ldc_channel *lp)
430 {
431 struct ldc_packet *p;
432 unsigned long new_tail;
433
434 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTS, NULL, 0,
435 &new_tail);
436 if (p) {
437 p->env = lp->cfg.mode;
438 p->seqid = 0;
439 lp->rcv_nxt = 0;
440
441 ldcdbg(HS, "SEND RTS env[0x%x] seqid[0x%x]\n",
442 p->env, p->seqid);
443
444 return send_tx_packet(lp, p, new_tail);
445 }
446 return -EBUSY;
447 }
448
449 static int send_rtr(struct ldc_channel *lp)
450 {
451 struct ldc_packet *p;
452 unsigned long new_tail;
453
454 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTR, NULL, 0,
455 &new_tail);
456 if (p) {
457 p->env = lp->cfg.mode;
458 p->seqid = 0;
459
460 ldcdbg(HS, "SEND RTR env[0x%x] seqid[0x%x]\n",
461 p->env, p->seqid);
462
463 return send_tx_packet(lp, p, new_tail);
464 }
465 return -EBUSY;
466 }
467
468 static int send_rdx(struct ldc_channel *lp)
469 {
470 struct ldc_packet *p;
471 unsigned long new_tail;
472
473 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RDX, NULL, 0,
474 &new_tail);
475 if (p) {
476 p->env = 0;
477 p->seqid = ++lp->snd_nxt;
478 p->u.r.ackid = lp->rcv_nxt;
479
480 ldcdbg(HS, "SEND RDX env[0x%x] seqid[0x%x] ackid[0x%x]\n",
481 p->env, p->seqid, p->u.r.ackid);
482
483 return send_tx_packet(lp, p, new_tail);
484 }
485 return -EBUSY;
486 }
487
488 static int send_data_nack(struct ldc_channel *lp, struct ldc_packet *data_pkt)
489 {
490 struct ldc_packet *p;
491 unsigned long new_tail;
492 int err;
493
494 p = data_get_tx_packet(lp, &new_tail);
495 if (!p)
496 return -EBUSY;
497 memset(p, 0, sizeof(*p));
498 p->type = data_pkt->type;
499 p->stype = LDC_NACK;
500 p->ctrl = data_pkt->ctrl & LDC_CTRL_MSK;
501 p->seqid = lp->snd_nxt + 1;
502 p->u.r.ackid = lp->rcv_nxt;
503
504 ldcdbg(HS, "SEND DATA NACK type[0x%x] ctl[0x%x] seq[0x%x] ack[0x%x]\n",
505 p->type, p->ctrl, p->seqid, p->u.r.ackid);
506
507 err = send_tx_packet(lp, p, new_tail);
508 if (!err)
509 lp->snd_nxt++;
510
511 return err;
512 }
513
514 static int ldc_abort(struct ldc_channel *lp)
515 {
516 unsigned long hv_err;
517
518 ldcdbg(STATE, "ABORT\n");
519
520 /* We report but do not act upon the hypervisor errors because
521 * there really isn't much we can do if they fail at this point.
522 */
523 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
524 if (hv_err)
525 printk(KERN_ERR PFX "ldc_abort: "
526 "sun4v_ldc_tx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
527 lp->id, lp->tx_ra, lp->tx_num_entries, hv_err);
528
529 hv_err = sun4v_ldc_tx_get_state(lp->id,
530 &lp->tx_head,
531 &lp->tx_tail,
532 &lp->chan_state);
533 if (hv_err)
534 printk(KERN_ERR PFX "ldc_abort: "
535 "sun4v_ldc_tx_get_state(%lx,...) failed, err=%lu\n",
536 lp->id, hv_err);
537
538 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
539 if (hv_err)
540 printk(KERN_ERR PFX "ldc_abort: "
541 "sun4v_ldc_rx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
542 lp->id, lp->rx_ra, lp->rx_num_entries, hv_err);
543
544 /* Refetch the RX queue state as well, because we could be invoked
545 * here in the queue processing context.
546 */
547 hv_err = sun4v_ldc_rx_get_state(lp->id,
548 &lp->rx_head,
549 &lp->rx_tail,
550 &lp->chan_state);
551 if (hv_err)
552 printk(KERN_ERR PFX "ldc_abort: "
553 "sun4v_ldc_rx_get_state(%lx,...) failed, err=%lu\n",
554 lp->id, hv_err);
555
556 return -ECONNRESET;
557 }
558
559 static struct ldc_version *find_by_major(u16 major)
560 {
561 struct ldc_version *ret = NULL;
562 int i;
563
564 for (i = 0; i < ARRAY_SIZE(ver_arr); i++) {
565 struct ldc_version *v = &ver_arr[i];
566 if (v->major <= major) {
567 ret = v;
568 break;
569 }
570 }
571 return ret;
572 }
573
574 static int process_ver_info(struct ldc_channel *lp, struct ldc_version *vp)
575 {
576 struct ldc_version *vap;
577 int err;
578
579 ldcdbg(HS, "GOT VERSION INFO major[%x] minor[%x]\n",
580 vp->major, vp->minor);
581
582 if (lp->hs_state == LDC_HS_GOTVERS) {
583 lp->hs_state = LDC_HS_OPEN;
584 memset(&lp->ver, 0, sizeof(lp->ver));
585 }
586
587 vap = find_by_major(vp->major);
588 if (!vap) {
589 err = send_version_nack(lp, 0, 0);
590 } else if (vap->major != vp->major) {
591 err = send_version_nack(lp, vap->major, vap->minor);
592 } else {
593 struct ldc_version ver = *vp;
594 if (ver.minor > vap->minor)
595 ver.minor = vap->minor;
596 err = send_version_ack(lp, &ver);
597 if (!err) {
598 lp->ver = ver;
599 lp->hs_state = LDC_HS_GOTVERS;
600 }
601 }
602 if (err)
603 return ldc_abort(lp);
604
605 return 0;
606 }
607
608 static int process_ver_ack(struct ldc_channel *lp, struct ldc_version *vp)
609 {
610 ldcdbg(HS, "GOT VERSION ACK major[%x] minor[%x]\n",
611 vp->major, vp->minor);
612
613 if (lp->hs_state == LDC_HS_GOTVERS) {
614 if (lp->ver.major != vp->major ||
615 lp->ver.minor != vp->minor)
616 return ldc_abort(lp);
617 } else {
618 lp->ver = *vp;
619 lp->hs_state = LDC_HS_GOTVERS;
620 }
621 if (send_rts(lp))
622 return ldc_abort(lp);
623 return 0;
624 }
625
626 static int process_ver_nack(struct ldc_channel *lp, struct ldc_version *vp)
627 {
628 struct ldc_version *vap;
629 struct ldc_packet *p;
630 unsigned long new_tail;
631
632 if (vp->major == 0 && vp->minor == 0)
633 return ldc_abort(lp);
634
635 vap = find_by_major(vp->major);
636 if (!vap)
637 return ldc_abort(lp);
638
639 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
640 vap, sizeof(*vap),
641 &new_tail);
642 if (!p)
643 return ldc_abort(lp);
644
645 return send_tx_packet(lp, p, new_tail);
646 }
647
648 static int process_version(struct ldc_channel *lp,
649 struct ldc_packet *p)
650 {
651 struct ldc_version *vp;
652
653 vp = (struct ldc_version *) p->u.u_data;
654
655 switch (p->stype) {
656 case LDC_INFO:
657 return process_ver_info(lp, vp);
658
659 case LDC_ACK:
660 return process_ver_ack(lp, vp);
661
662 case LDC_NACK:
663 return process_ver_nack(lp, vp);
664
665 default:
666 return ldc_abort(lp);
667 }
668 }
669
670 static int process_rts(struct ldc_channel *lp,
671 struct ldc_packet *p)
672 {
673 ldcdbg(HS, "GOT RTS stype[%x] seqid[%x] env[%x]\n",
674 p->stype, p->seqid, p->env);
675
676 if (p->stype != LDC_INFO ||
677 lp->hs_state != LDC_HS_GOTVERS ||
678 p->env != lp->cfg.mode)
679 return ldc_abort(lp);
680
681 lp->snd_nxt = p->seqid;
682 lp->rcv_nxt = p->seqid;
683 lp->hs_state = LDC_HS_SENTRTR;
684 if (send_rtr(lp))
685 return ldc_abort(lp);
686
687 return 0;
688 }
689
690 static int process_rtr(struct ldc_channel *lp,
691 struct ldc_packet *p)
692 {
693 ldcdbg(HS, "GOT RTR stype[%x] seqid[%x] env[%x]\n",
694 p->stype, p->seqid, p->env);
695
696 if (p->stype != LDC_INFO ||
697 p->env != lp->cfg.mode)
698 return ldc_abort(lp);
699
700 lp->snd_nxt = p->seqid;
701 lp->hs_state = LDC_HS_COMPLETE;
702 ldc_set_state(lp, LDC_STATE_CONNECTED);
703 send_rdx(lp);
704
705 return LDC_EVENT_UP;
706 }
707
708 static int rx_seq_ok(struct ldc_channel *lp, u32 seqid)
709 {
710 return lp->rcv_nxt + 1 == seqid;
711 }
712
713 static int process_rdx(struct ldc_channel *lp,
714 struct ldc_packet *p)
715 {
716 ldcdbg(HS, "GOT RDX stype[%x] seqid[%x] env[%x] ackid[%x]\n",
717 p->stype, p->seqid, p->env, p->u.r.ackid);
718
719 if (p->stype != LDC_INFO ||
720 !(rx_seq_ok(lp, p->seqid)))
721 return ldc_abort(lp);
722
723 lp->rcv_nxt = p->seqid;
724
725 lp->hs_state = LDC_HS_COMPLETE;
726 ldc_set_state(lp, LDC_STATE_CONNECTED);
727
728 return LDC_EVENT_UP;
729 }
730
731 static int process_control_frame(struct ldc_channel *lp,
732 struct ldc_packet *p)
733 {
734 switch (p->ctrl) {
735 case LDC_VERS:
736 return process_version(lp, p);
737
738 case LDC_RTS:
739 return process_rts(lp, p);
740
741 case LDC_RTR:
742 return process_rtr(lp, p);
743
744 case LDC_RDX:
745 return process_rdx(lp, p);
746
747 default:
748 return ldc_abort(lp);
749 }
750 }
751
752 static int process_error_frame(struct ldc_channel *lp,
753 struct ldc_packet *p)
754 {
755 return ldc_abort(lp);
756 }
757
758 static int process_data_ack(struct ldc_channel *lp,
759 struct ldc_packet *ack)
760 {
761 unsigned long head = lp->tx_acked;
762 u32 ackid = ack->u.r.ackid;
763
764 while (1) {
765 struct ldc_packet *p = lp->tx_base + (head / LDC_PACKET_SIZE);
766
767 head = tx_advance(lp, head);
768
769 if (p->seqid == ackid) {
770 lp->tx_acked = head;
771 return 0;
772 }
773 if (head == lp->tx_tail)
774 return ldc_abort(lp);
775 }
776
777 return 0;
778 }
779
780 static void send_events(struct ldc_channel *lp, unsigned int event_mask)
781 {
782 if (event_mask & LDC_EVENT_RESET)
783 lp->cfg.event(lp->event_arg, LDC_EVENT_RESET);
784 if (event_mask & LDC_EVENT_UP)
785 lp->cfg.event(lp->event_arg, LDC_EVENT_UP);
786 if (event_mask & LDC_EVENT_DATA_READY)
787 lp->cfg.event(lp->event_arg, LDC_EVENT_DATA_READY);
788 }
789
790 static irqreturn_t ldc_rx(int irq, void *dev_id)
791 {
792 struct ldc_channel *lp = dev_id;
793 unsigned long orig_state, flags;
794 unsigned int event_mask;
795
796 spin_lock_irqsave(&lp->lock, flags);
797
798 orig_state = lp->chan_state;
799
800 /* We should probably check for hypervisor errors here and
801 * reset the LDC channel if we get one.
802 */
803 sun4v_ldc_rx_get_state(lp->id,
804 &lp->rx_head,
805 &lp->rx_tail,
806 &lp->chan_state);
807
808 ldcdbg(RX, "RX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
809 orig_state, lp->chan_state, lp->rx_head, lp->rx_tail);
810
811 event_mask = 0;
812
813 if (lp->cfg.mode == LDC_MODE_RAW &&
814 lp->chan_state == LDC_CHANNEL_UP) {
815 lp->hs_state = LDC_HS_COMPLETE;
816 ldc_set_state(lp, LDC_STATE_CONNECTED);
817
818 event_mask |= LDC_EVENT_UP;
819
820 orig_state = lp->chan_state;
821 }
822
823 /* If we are in reset state, flush the RX queue and ignore
824 * everything.
825 */
826 if (lp->flags & LDC_FLAG_RESET) {
827 (void) __set_rx_head(lp, lp->rx_tail);
828 goto out;
829 }
830
831 /* Once we finish the handshake, we let the ldc_read()
832 * paths do all of the control frame and state management.
833 * Just trigger the callback.
834 */
835 if (lp->hs_state == LDC_HS_COMPLETE) {
836 handshake_complete:
837 if (lp->chan_state != orig_state) {
838 unsigned int event = LDC_EVENT_RESET;
839
840 if (lp->chan_state == LDC_CHANNEL_UP)
841 event = LDC_EVENT_UP;
842
843 event_mask |= event;
844 }
845 if (lp->rx_head != lp->rx_tail)
846 event_mask |= LDC_EVENT_DATA_READY;
847
848 goto out;
849 }
850
851 if (lp->chan_state != orig_state)
852 goto out;
853
854 while (lp->rx_head != lp->rx_tail) {
855 struct ldc_packet *p;
856 unsigned long new;
857 int err;
858
859 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
860
861 switch (p->type) {
862 case LDC_CTRL:
863 err = process_control_frame(lp, p);
864 if (err > 0)
865 event_mask |= err;
866 break;
867
868 case LDC_DATA:
869 event_mask |= LDC_EVENT_DATA_READY;
870 err = 0;
871 break;
872
873 case LDC_ERR:
874 err = process_error_frame(lp, p);
875 break;
876
877 default:
878 err = ldc_abort(lp);
879 break;
880 }
881
882 if (err < 0)
883 break;
884
885 new = lp->rx_head;
886 new += LDC_PACKET_SIZE;
887 if (new == (lp->rx_num_entries * LDC_PACKET_SIZE))
888 new = 0;
889 lp->rx_head = new;
890
891 err = __set_rx_head(lp, new);
892 if (err < 0) {
893 (void) ldc_abort(lp);
894 break;
895 }
896 if (lp->hs_state == LDC_HS_COMPLETE)
897 goto handshake_complete;
898 }
899
900 out:
901 spin_unlock_irqrestore(&lp->lock, flags);
902
903 send_events(lp, event_mask);
904
905 return IRQ_HANDLED;
906 }
907
908 static irqreturn_t ldc_tx(int irq, void *dev_id)
909 {
910 struct ldc_channel *lp = dev_id;
911 unsigned long flags, orig_state;
912 unsigned int event_mask = 0;
913
914 spin_lock_irqsave(&lp->lock, flags);
915
916 orig_state = lp->chan_state;
917
918 /* We should probably check for hypervisor errors here and
919 * reset the LDC channel if we get one.
920 */
921 sun4v_ldc_tx_get_state(lp->id,
922 &lp->tx_head,
923 &lp->tx_tail,
924 &lp->chan_state);
925
926 ldcdbg(TX, " TX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
927 orig_state, lp->chan_state, lp->tx_head, lp->tx_tail);
928
929 if (lp->cfg.mode == LDC_MODE_RAW &&
930 lp->chan_state == LDC_CHANNEL_UP) {
931 lp->hs_state = LDC_HS_COMPLETE;
932 ldc_set_state(lp, LDC_STATE_CONNECTED);
933
934 event_mask |= LDC_EVENT_UP;
935 }
936
937 spin_unlock_irqrestore(&lp->lock, flags);
938
939 send_events(lp, event_mask);
940
941 return IRQ_HANDLED;
942 }
943
944 /* XXX ldc_alloc() and ldc_free() needs to run under a mutex so
945 * XXX that addition and removal from the ldc_channel_list has
946 * XXX atomicity, otherwise the __ldc_channel_exists() check is
947 * XXX totally pointless as another thread can slip into ldc_alloc()
948 * XXX and add a channel with the same ID. There also needs to be
949 * XXX a spinlock for ldc_channel_list.
950 */
951 static HLIST_HEAD(ldc_channel_list);
952
953 static int __ldc_channel_exists(unsigned long id)
954 {
955 struct ldc_channel *lp;
956
957 hlist_for_each_entry(lp, &ldc_channel_list, list) {
958 if (lp->id == id)
959 return 1;
960 }
961 return 0;
962 }
963
964 static int alloc_queue(const char *name, unsigned long num_entries,
965 struct ldc_packet **base, unsigned long *ra)
966 {
967 unsigned long size, order;
968 void *q;
969
970 size = num_entries * LDC_PACKET_SIZE;
971 order = get_order(size);
972
973 q = (void *) __get_free_pages(GFP_KERNEL, order);
974 if (!q) {
975 printk(KERN_ERR PFX "Alloc of %s queue failed with "
976 "size=%lu order=%lu\n", name, size, order);
977 return -ENOMEM;
978 }
979
980 memset(q, 0, PAGE_SIZE << order);
981
982 *base = q;
983 *ra = __pa(q);
984
985 return 0;
986 }
987
988 static void free_queue(unsigned long num_entries, struct ldc_packet *q)
989 {
990 unsigned long size, order;
991
992 if (!q)
993 return;
994
995 size = num_entries * LDC_PACKET_SIZE;
996 order = get_order(size);
997
998 free_pages((unsigned long)q, order);
999 }
1000
1001 /* XXX Make this configurable... XXX */
1002 #define LDC_IOTABLE_SIZE (8 * 1024)
1003
1004 static int ldc_iommu_init(struct ldc_channel *lp)
1005 {
1006 unsigned long sz, num_tsb_entries, tsbsize, order;
1007 struct ldc_iommu *iommu = &lp->iommu;
1008 struct ldc_mtable_entry *table;
1009 unsigned long hv_err;
1010 int err;
1011
1012 num_tsb_entries = LDC_IOTABLE_SIZE;
1013 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1014
1015 spin_lock_init(&iommu->lock);
1016
1017 sz = num_tsb_entries / 8;
1018 sz = (sz + 7UL) & ~7UL;
1019 iommu->arena.map = kzalloc(sz, GFP_KERNEL);
1020 if (!iommu->arena.map) {
1021 printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz);
1022 return -ENOMEM;
1023 }
1024
1025 iommu->arena.limit = num_tsb_entries;
1026
1027 order = get_order(tsbsize);
1028
1029 table = (struct ldc_mtable_entry *)
1030 __get_free_pages(GFP_KERNEL, order);
1031 err = -ENOMEM;
1032 if (!table) {
1033 printk(KERN_ERR PFX "Alloc of MTE table failed, "
1034 "size=%lu order=%lu\n", tsbsize, order);
1035 goto out_free_map;
1036 }
1037
1038 memset(table, 0, PAGE_SIZE << order);
1039
1040 iommu->page_table = table;
1041
1042 hv_err = sun4v_ldc_set_map_table(lp->id, __pa(table),
1043 num_tsb_entries);
1044 err = -EINVAL;
1045 if (hv_err)
1046 goto out_free_table;
1047
1048 return 0;
1049
1050 out_free_table:
1051 free_pages((unsigned long) table, order);
1052 iommu->page_table = NULL;
1053
1054 out_free_map:
1055 kfree(iommu->arena.map);
1056 iommu->arena.map = NULL;
1057
1058 return err;
1059 }
1060
1061 static void ldc_iommu_release(struct ldc_channel *lp)
1062 {
1063 struct ldc_iommu *iommu = &lp->iommu;
1064 unsigned long num_tsb_entries, tsbsize, order;
1065
1066 (void) sun4v_ldc_set_map_table(lp->id, 0, 0);
1067
1068 num_tsb_entries = iommu->arena.limit;
1069 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1070 order = get_order(tsbsize);
1071
1072 free_pages((unsigned long) iommu->page_table, order);
1073 iommu->page_table = NULL;
1074
1075 kfree(iommu->arena.map);
1076 iommu->arena.map = NULL;
1077 }
1078
1079 struct ldc_channel *ldc_alloc(unsigned long id,
1080 const struct ldc_channel_config *cfgp,
1081 void *event_arg,
1082 const char *name)
1083 {
1084 struct ldc_channel *lp;
1085 const struct ldc_mode_ops *mops;
1086 unsigned long dummy1, dummy2, hv_err;
1087 u8 mss, *mssbuf;
1088 int err;
1089
1090 err = -ENODEV;
1091 if (!ldom_domaining_enabled)
1092 goto out_err;
1093
1094 err = -EINVAL;
1095 if (!cfgp)
1096 goto out_err;
1097 if (!name)
1098 goto out_err;
1099
1100 switch (cfgp->mode) {
1101 case LDC_MODE_RAW:
1102 mops = &raw_ops;
1103 mss = LDC_PACKET_SIZE;
1104 break;
1105
1106 case LDC_MODE_UNRELIABLE:
1107 mops = &nonraw_ops;
1108 mss = LDC_PACKET_SIZE - 8;
1109 break;
1110
1111 case LDC_MODE_STREAM:
1112 mops = &stream_ops;
1113 mss = LDC_PACKET_SIZE - 8 - 8;
1114 break;
1115
1116 default:
1117 goto out_err;
1118 }
1119
1120 if (!cfgp->event || !event_arg || !cfgp->rx_irq || !cfgp->tx_irq)
1121 goto out_err;
1122
1123 hv_err = sun4v_ldc_tx_qinfo(id, &dummy1, &dummy2);
1124 err = -ENODEV;
1125 if (hv_err == HV_ECHANNEL)
1126 goto out_err;
1127
1128 err = -EEXIST;
1129 if (__ldc_channel_exists(id))
1130 goto out_err;
1131
1132 mssbuf = NULL;
1133
1134 lp = kzalloc(sizeof(*lp), GFP_KERNEL);
1135 err = -ENOMEM;
1136 if (!lp)
1137 goto out_err;
1138
1139 spin_lock_init(&lp->lock);
1140
1141 lp->id = id;
1142
1143 err = ldc_iommu_init(lp);
1144 if (err)
1145 goto out_free_ldc;
1146
1147 lp->mops = mops;
1148 lp->mss = mss;
1149
1150 lp->cfg = *cfgp;
1151 if (!lp->cfg.mtu)
1152 lp->cfg.mtu = LDC_DEFAULT_MTU;
1153
1154 if (lp->cfg.mode == LDC_MODE_STREAM) {
1155 mssbuf = kzalloc(lp->cfg.mtu, GFP_KERNEL);
1156 if (!mssbuf) {
1157 err = -ENOMEM;
1158 goto out_free_iommu;
1159 }
1160 lp->mssbuf = mssbuf;
1161 }
1162
1163 lp->event_arg = event_arg;
1164
1165 /* XXX allow setting via ldc_channel_config to override defaults
1166 * XXX or use some formula based upon mtu
1167 */
1168 lp->tx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1169 lp->rx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1170
1171 err = alloc_queue("TX", lp->tx_num_entries,
1172 &lp->tx_base, &lp->tx_ra);
1173 if (err)
1174 goto out_free_mssbuf;
1175
1176 err = alloc_queue("RX", lp->rx_num_entries,
1177 &lp->rx_base, &lp->rx_ra);
1178 if (err)
1179 goto out_free_txq;
1180
1181 lp->flags |= LDC_FLAG_ALLOCED_QUEUES;
1182
1183 lp->hs_state = LDC_HS_CLOSED;
1184 ldc_set_state(lp, LDC_STATE_INIT);
1185
1186 INIT_HLIST_NODE(&lp->list);
1187 hlist_add_head(&lp->list, &ldc_channel_list);
1188
1189 INIT_HLIST_HEAD(&lp->mh_list);
1190
1191 snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name);
1192 snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name);
1193
1194 err = request_irq(lp->cfg.rx_irq, ldc_rx, 0,
1195 lp->rx_irq_name, lp);
1196 if (err)
1197 goto out_free_txq;
1198
1199 err = request_irq(lp->cfg.tx_irq, ldc_tx, 0,
1200 lp->tx_irq_name, lp);
1201 if (err) {
1202 free_irq(lp->cfg.rx_irq, lp);
1203 goto out_free_txq;
1204 }
1205
1206 return lp;
1207
1208 out_free_txq:
1209 free_queue(lp->tx_num_entries, lp->tx_base);
1210
1211 out_free_mssbuf:
1212 kfree(mssbuf);
1213
1214 out_free_iommu:
1215 ldc_iommu_release(lp);
1216
1217 out_free_ldc:
1218 kfree(lp);
1219
1220 out_err:
1221 return ERR_PTR(err);
1222 }
1223 EXPORT_SYMBOL(ldc_alloc);
1224
1225 void ldc_unbind(struct ldc_channel *lp)
1226 {
1227 if (lp->flags & LDC_FLAG_REGISTERED_IRQS) {
1228 free_irq(lp->cfg.rx_irq, lp);
1229 free_irq(lp->cfg.tx_irq, lp);
1230 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
1231 }
1232
1233 if (lp->flags & LDC_FLAG_REGISTERED_QUEUES) {
1234 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1235 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1236 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1237 }
1238 if (lp->flags & LDC_FLAG_ALLOCED_QUEUES) {
1239 free_queue(lp->tx_num_entries, lp->tx_base);
1240 free_queue(lp->rx_num_entries, lp->rx_base);
1241 lp->flags &= ~LDC_FLAG_ALLOCED_QUEUES;
1242 }
1243
1244 ldc_set_state(lp, LDC_STATE_INIT);
1245 }
1246 EXPORT_SYMBOL(ldc_unbind);
1247
1248 void ldc_free(struct ldc_channel *lp)
1249 {
1250 ldc_unbind(lp);
1251 hlist_del(&lp->list);
1252 kfree(lp->mssbuf);
1253 ldc_iommu_release(lp);
1254
1255 kfree(lp);
1256 }
1257 EXPORT_SYMBOL(ldc_free);
1258
1259 /* Bind the channel. This registers the LDC queues with
1260 * the hypervisor and puts the channel into a pseudo-listening
1261 * state. This does not initiate a handshake, ldc_connect() does
1262 * that.
1263 */
1264 int ldc_bind(struct ldc_channel *lp)
1265 {
1266 unsigned long hv_err, flags;
1267 int err = -EINVAL;
1268
1269 if (lp->state != LDC_STATE_INIT)
1270 return -EINVAL;
1271
1272 spin_lock_irqsave(&lp->lock, flags);
1273
1274 enable_irq(lp->cfg.rx_irq);
1275 enable_irq(lp->cfg.tx_irq);
1276
1277 lp->flags |= LDC_FLAG_REGISTERED_IRQS;
1278
1279 err = -ENODEV;
1280 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1281 if (hv_err)
1282 goto out_free_irqs;
1283
1284 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1285 if (hv_err)
1286 goto out_free_irqs;
1287
1288 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1289 if (hv_err)
1290 goto out_unmap_tx;
1291
1292 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1293 if (hv_err)
1294 goto out_unmap_tx;
1295
1296 lp->flags |= LDC_FLAG_REGISTERED_QUEUES;
1297
1298 hv_err = sun4v_ldc_tx_get_state(lp->id,
1299 &lp->tx_head,
1300 &lp->tx_tail,
1301 &lp->chan_state);
1302 err = -EBUSY;
1303 if (hv_err)
1304 goto out_unmap_rx;
1305
1306 lp->tx_acked = lp->tx_head;
1307
1308 lp->hs_state = LDC_HS_OPEN;
1309 ldc_set_state(lp, LDC_STATE_BOUND);
1310
1311 spin_unlock_irqrestore(&lp->lock, flags);
1312
1313 return 0;
1314
1315 out_unmap_rx:
1316 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1317 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1318
1319 out_unmap_tx:
1320 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1321
1322 out_free_irqs:
1323 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
1324 free_irq(lp->cfg.tx_irq, lp);
1325 free_irq(lp->cfg.rx_irq, lp);
1326
1327 spin_unlock_irqrestore(&lp->lock, flags);
1328
1329 return err;
1330 }
1331 EXPORT_SYMBOL(ldc_bind);
1332
1333 int ldc_connect(struct ldc_channel *lp)
1334 {
1335 unsigned long flags;
1336 int err;
1337
1338 if (lp->cfg.mode == LDC_MODE_RAW)
1339 return -EINVAL;
1340
1341 spin_lock_irqsave(&lp->lock, flags);
1342
1343 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1344 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES) ||
1345 lp->hs_state != LDC_HS_OPEN)
1346 err = ((lp->hs_state > LDC_HS_OPEN) ? 0 : -EINVAL);
1347 else
1348 err = start_handshake(lp);
1349
1350 spin_unlock_irqrestore(&lp->lock, flags);
1351
1352 return err;
1353 }
1354 EXPORT_SYMBOL(ldc_connect);
1355
1356 int ldc_disconnect(struct ldc_channel *lp)
1357 {
1358 unsigned long hv_err, flags;
1359 int err;
1360
1361 if (lp->cfg.mode == LDC_MODE_RAW)
1362 return -EINVAL;
1363
1364 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1365 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES))
1366 return -EINVAL;
1367
1368 spin_lock_irqsave(&lp->lock, flags);
1369
1370 err = -ENODEV;
1371 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1372 if (hv_err)
1373 goto out_err;
1374
1375 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1376 if (hv_err)
1377 goto out_err;
1378
1379 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1380 if (hv_err)
1381 goto out_err;
1382
1383 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1384 if (hv_err)
1385 goto out_err;
1386
1387 ldc_set_state(lp, LDC_STATE_BOUND);
1388 lp->hs_state = LDC_HS_OPEN;
1389 lp->flags |= LDC_FLAG_RESET;
1390
1391 spin_unlock_irqrestore(&lp->lock, flags);
1392
1393 return 0;
1394
1395 out_err:
1396 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1397 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1398 free_irq(lp->cfg.tx_irq, lp);
1399 free_irq(lp->cfg.rx_irq, lp);
1400 lp->flags &= ~(LDC_FLAG_REGISTERED_IRQS |
1401 LDC_FLAG_REGISTERED_QUEUES);
1402 ldc_set_state(lp, LDC_STATE_INIT);
1403
1404 spin_unlock_irqrestore(&lp->lock, flags);
1405
1406 return err;
1407 }
1408 EXPORT_SYMBOL(ldc_disconnect);
1409
1410 int ldc_state(struct ldc_channel *lp)
1411 {
1412 return lp->state;
1413 }
1414 EXPORT_SYMBOL(ldc_state);
1415
1416 static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size)
1417 {
1418 struct ldc_packet *p;
1419 unsigned long new_tail;
1420 int err;
1421
1422 if (size > LDC_PACKET_SIZE)
1423 return -EMSGSIZE;
1424
1425 p = data_get_tx_packet(lp, &new_tail);
1426 if (!p)
1427 return -EAGAIN;
1428
1429 memcpy(p, buf, size);
1430
1431 err = send_tx_packet(lp, p, new_tail);
1432 if (!err)
1433 err = size;
1434
1435 return err;
1436 }
1437
1438 static int read_raw(struct ldc_channel *lp, void *buf, unsigned int size)
1439 {
1440 struct ldc_packet *p;
1441 unsigned long hv_err, new;
1442 int err;
1443
1444 if (size < LDC_PACKET_SIZE)
1445 return -EINVAL;
1446
1447 hv_err = sun4v_ldc_rx_get_state(lp->id,
1448 &lp->rx_head,
1449 &lp->rx_tail,
1450 &lp->chan_state);
1451 if (hv_err)
1452 return ldc_abort(lp);
1453
1454 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1455 lp->chan_state == LDC_CHANNEL_RESETTING)
1456 return -ECONNRESET;
1457
1458 if (lp->rx_head == lp->rx_tail)
1459 return 0;
1460
1461 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
1462 memcpy(buf, p, LDC_PACKET_SIZE);
1463
1464 new = rx_advance(lp, lp->rx_head);
1465 lp->rx_head = new;
1466
1467 err = __set_rx_head(lp, new);
1468 if (err < 0)
1469 err = -ECONNRESET;
1470 else
1471 err = LDC_PACKET_SIZE;
1472
1473 return err;
1474 }
1475
1476 static const struct ldc_mode_ops raw_ops = {
1477 .write = write_raw,
1478 .read = read_raw,
1479 };
1480
1481 static int write_nonraw(struct ldc_channel *lp, const void *buf,
1482 unsigned int size)
1483 {
1484 unsigned long hv_err, tail;
1485 unsigned int copied;
1486 u32 seq;
1487 int err;
1488
1489 hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail,
1490 &lp->chan_state);
1491 if (unlikely(hv_err))
1492 return -EBUSY;
1493
1494 if (unlikely(lp->chan_state != LDC_CHANNEL_UP))
1495 return ldc_abort(lp);
1496
1497 if (!tx_has_space_for(lp, size))
1498 return -EAGAIN;
1499
1500 seq = lp->snd_nxt;
1501 copied = 0;
1502 tail = lp->tx_tail;
1503 while (copied < size) {
1504 struct ldc_packet *p = lp->tx_base + (tail / LDC_PACKET_SIZE);
1505 u8 *data = ((lp->cfg.mode == LDC_MODE_UNRELIABLE) ?
1506 p->u.u_data :
1507 p->u.r.r_data);
1508 int data_len;
1509
1510 p->type = LDC_DATA;
1511 p->stype = LDC_INFO;
1512 p->ctrl = 0;
1513
1514 data_len = size - copied;
1515 if (data_len > lp->mss)
1516 data_len = lp->mss;
1517
1518 BUG_ON(data_len > LDC_LEN);
1519
1520 p->env = (data_len |
1521 (copied == 0 ? LDC_START : 0) |
1522 (data_len == size - copied ? LDC_STOP : 0));
1523
1524 p->seqid = ++seq;
1525
1526 ldcdbg(DATA, "SENT DATA [%02x:%02x:%02x:%02x:%08x]\n",
1527 p->type,
1528 p->stype,
1529 p->ctrl,
1530 p->env,
1531 p->seqid);
1532
1533 memcpy(data, buf, data_len);
1534 buf += data_len;
1535 copied += data_len;
1536
1537 tail = tx_advance(lp, tail);
1538 }
1539
1540 err = set_tx_tail(lp, tail);
1541 if (!err) {
1542 lp->snd_nxt = seq;
1543 err = size;
1544 }
1545
1546 return err;
1547 }
1548
1549 static int rx_bad_seq(struct ldc_channel *lp, struct ldc_packet *p,
1550 struct ldc_packet *first_frag)
1551 {
1552 int err;
1553
1554 if (first_frag)
1555 lp->rcv_nxt = first_frag->seqid - 1;
1556
1557 err = send_data_nack(lp, p);
1558 if (err)
1559 return err;
1560
1561 err = __set_rx_head(lp, lp->rx_tail);
1562 if (err < 0)
1563 return ldc_abort(lp);
1564
1565 return 0;
1566 }
1567
1568 static int data_ack_nack(struct ldc_channel *lp, struct ldc_packet *p)
1569 {
1570 if (p->stype & LDC_ACK) {
1571 int err = process_data_ack(lp, p);
1572 if (err)
1573 return err;
1574 }
1575 if (p->stype & LDC_NACK)
1576 return ldc_abort(lp);
1577
1578 return 0;
1579 }
1580
1581 static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head)
1582 {
1583 unsigned long dummy;
1584 int limit = 1000;
1585
1586 ldcdbg(DATA, "DATA WAIT cur_head[%lx] rx_head[%lx] rx_tail[%lx]\n",
1587 cur_head, lp->rx_head, lp->rx_tail);
1588 while (limit-- > 0) {
1589 unsigned long hv_err;
1590
1591 hv_err = sun4v_ldc_rx_get_state(lp->id,
1592 &dummy,
1593 &lp->rx_tail,
1594 &lp->chan_state);
1595 if (hv_err)
1596 return ldc_abort(lp);
1597
1598 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1599 lp->chan_state == LDC_CHANNEL_RESETTING)
1600 return -ECONNRESET;
1601
1602 if (cur_head != lp->rx_tail) {
1603 ldcdbg(DATA, "DATA WAIT DONE "
1604 "head[%lx] tail[%lx] chan_state[%lx]\n",
1605 dummy, lp->rx_tail, lp->chan_state);
1606 return 0;
1607 }
1608
1609 udelay(1);
1610 }
1611 return -EAGAIN;
1612 }
1613
1614 static int rx_set_head(struct ldc_channel *lp, unsigned long head)
1615 {
1616 int err = __set_rx_head(lp, head);
1617
1618 if (err < 0)
1619 return ldc_abort(lp);
1620
1621 lp->rx_head = head;
1622 return 0;
1623 }
1624
1625 static void send_data_ack(struct ldc_channel *lp)
1626 {
1627 unsigned long new_tail;
1628 struct ldc_packet *p;
1629
1630 p = data_get_tx_packet(lp, &new_tail);
1631 if (likely(p)) {
1632 int err;
1633
1634 memset(p, 0, sizeof(*p));
1635 p->type = LDC_DATA;
1636 p->stype = LDC_ACK;
1637 p->ctrl = 0;
1638 p->seqid = lp->snd_nxt + 1;
1639 p->u.r.ackid = lp->rcv_nxt;
1640
1641 err = send_tx_packet(lp, p, new_tail);
1642 if (!err)
1643 lp->snd_nxt++;
1644 }
1645 }
1646
1647 static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
1648 {
1649 struct ldc_packet *first_frag;
1650 unsigned long hv_err, new;
1651 int err, copied;
1652
1653 hv_err = sun4v_ldc_rx_get_state(lp->id,
1654 &lp->rx_head,
1655 &lp->rx_tail,
1656 &lp->chan_state);
1657 if (hv_err)
1658 return ldc_abort(lp);
1659
1660 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1661 lp->chan_state == LDC_CHANNEL_RESETTING)
1662 return -ECONNRESET;
1663
1664 if (lp->rx_head == lp->rx_tail)
1665 return 0;
1666
1667 first_frag = NULL;
1668 copied = err = 0;
1669 new = lp->rx_head;
1670 while (1) {
1671 struct ldc_packet *p;
1672 int pkt_len;
1673
1674 BUG_ON(new == lp->rx_tail);
1675 p = lp->rx_base + (new / LDC_PACKET_SIZE);
1676
1677 ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x:%08x] "
1678 "rcv_nxt[%08x]\n",
1679 p->type,
1680 p->stype,
1681 p->ctrl,
1682 p->env,
1683 p->seqid,
1684 p->u.r.ackid,
1685 lp->rcv_nxt);
1686
1687 if (unlikely(!rx_seq_ok(lp, p->seqid))) {
1688 err = rx_bad_seq(lp, p, first_frag);
1689 copied = 0;
1690 break;
1691 }
1692
1693 if (p->type & LDC_CTRL) {
1694 err = process_control_frame(lp, p);
1695 if (err < 0)
1696 break;
1697 err = 0;
1698 }
1699
1700 lp->rcv_nxt = p->seqid;
1701
1702 if (!(p->type & LDC_DATA)) {
1703 new = rx_advance(lp, new);
1704 goto no_data;
1705 }
1706 if (p->stype & (LDC_ACK | LDC_NACK)) {
1707 err = data_ack_nack(lp, p);
1708 if (err)
1709 break;
1710 }
1711 if (!(p->stype & LDC_INFO)) {
1712 new = rx_advance(lp, new);
1713 err = rx_set_head(lp, new);
1714 if (err)
1715 break;
1716 goto no_data;
1717 }
1718
1719 pkt_len = p->env & LDC_LEN;
1720
1721 /* Every initial packet starts with the START bit set.
1722 *
1723 * Singleton packets will have both START+STOP set.
1724 *
1725 * Fragments will have START set in the first frame, STOP
1726 * set in the last frame, and neither bit set in middle
1727 * frames of the packet.
1728 *
1729 * Therefore if we are at the beginning of a packet and
1730 * we don't see START, or we are in the middle of a fragmented
1731 * packet and do see START, we are unsynchronized and should
1732 * flush the RX queue.
1733 */
1734 if ((first_frag == NULL && !(p->env & LDC_START)) ||
1735 (first_frag != NULL && (p->env & LDC_START))) {
1736 if (!first_frag)
1737 new = rx_advance(lp, new);
1738
1739 err = rx_set_head(lp, new);
1740 if (err)
1741 break;
1742
1743 if (!first_frag)
1744 goto no_data;
1745 }
1746 if (!first_frag)
1747 first_frag = p;
1748
1749 if (pkt_len > size - copied) {
1750 /* User didn't give us a big enough buffer,
1751 * what to do? This is a pretty serious error.
1752 *
1753 * Since we haven't updated the RX ring head to
1754 * consume any of the packets, signal the error
1755 * to the user and just leave the RX ring alone.
1756 *
1757 * This seems the best behavior because this allows
1758 * a user of the LDC layer to start with a small
1759 * RX buffer for ldc_read() calls and use -EMSGSIZE
1760 * as a cue to enlarge it's read buffer.
1761 */
1762 err = -EMSGSIZE;
1763 break;
1764 }
1765
1766 /* Ok, we are gonna eat this one. */
1767 new = rx_advance(lp, new);
1768
1769 memcpy(buf,
1770 (lp->cfg.mode == LDC_MODE_UNRELIABLE ?
1771 p->u.u_data : p->u.r.r_data), pkt_len);
1772 buf += pkt_len;
1773 copied += pkt_len;
1774
1775 if (p->env & LDC_STOP)
1776 break;
1777
1778 no_data:
1779 if (new == lp->rx_tail) {
1780 err = rx_data_wait(lp, new);
1781 if (err)
1782 break;
1783 }
1784 }
1785
1786 if (!err)
1787 err = rx_set_head(lp, new);
1788
1789 if (err && first_frag)
1790 lp->rcv_nxt = first_frag->seqid - 1;
1791
1792 if (!err) {
1793 err = copied;
1794 if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE)
1795 send_data_ack(lp);
1796 }
1797
1798 return err;
1799 }
1800
1801 static const struct ldc_mode_ops nonraw_ops = {
1802 .write = write_nonraw,
1803 .read = read_nonraw,
1804 };
1805
1806 static int write_stream(struct ldc_channel *lp, const void *buf,
1807 unsigned int size)
1808 {
1809 if (size > lp->cfg.mtu)
1810 size = lp->cfg.mtu;
1811 return write_nonraw(lp, buf, size);
1812 }
1813
1814 static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size)
1815 {
1816 if (!lp->mssbuf_len) {
1817 int err = read_nonraw(lp, lp->mssbuf, lp->cfg.mtu);
1818 if (err < 0)
1819 return err;
1820
1821 lp->mssbuf_len = err;
1822 lp->mssbuf_off = 0;
1823 }
1824
1825 if (size > lp->mssbuf_len)
1826 size = lp->mssbuf_len;
1827 memcpy(buf, lp->mssbuf + lp->mssbuf_off, size);
1828
1829 lp->mssbuf_off += size;
1830 lp->mssbuf_len -= size;
1831
1832 return size;
1833 }
1834
1835 static const struct ldc_mode_ops stream_ops = {
1836 .write = write_stream,
1837 .read = read_stream,
1838 };
1839
1840 int ldc_write(struct ldc_channel *lp, const void *buf, unsigned int size)
1841 {
1842 unsigned long flags;
1843 int err;
1844
1845 if (!buf)
1846 return -EINVAL;
1847
1848 if (!size)
1849 return 0;
1850
1851 spin_lock_irqsave(&lp->lock, flags);
1852
1853 if (lp->hs_state != LDC_HS_COMPLETE)
1854 err = -ENOTCONN;
1855 else
1856 err = lp->mops->write(lp, buf, size);
1857
1858 spin_unlock_irqrestore(&lp->lock, flags);
1859
1860 return err;
1861 }
1862 EXPORT_SYMBOL(ldc_write);
1863
1864 int ldc_read(struct ldc_channel *lp, void *buf, unsigned int size)
1865 {
1866 unsigned long flags;
1867 int err;
1868
1869 if (!buf)
1870 return -EINVAL;
1871
1872 if (!size)
1873 return 0;
1874
1875 spin_lock_irqsave(&lp->lock, flags);
1876
1877 if (lp->hs_state != LDC_HS_COMPLETE)
1878 err = -ENOTCONN;
1879 else
1880 err = lp->mops->read(lp, buf, size);
1881
1882 spin_unlock_irqrestore(&lp->lock, flags);
1883
1884 return err;
1885 }
1886 EXPORT_SYMBOL(ldc_read);
1887
1888 static long arena_alloc(struct ldc_iommu *iommu, unsigned long npages)
1889 {
1890 struct iommu_arena *arena = &iommu->arena;
1891 unsigned long n, start, end, limit;
1892 int pass;
1893
1894 limit = arena->limit;
1895 start = arena->hint;
1896 pass = 0;
1897
1898 again:
1899 n = bitmap_find_next_zero_area(arena->map, limit, start, npages, 0);
1900 end = n + npages;
1901 if (unlikely(end >= limit)) {
1902 if (likely(pass < 1)) {
1903 limit = start;
1904 start = 0;
1905 pass++;
1906 goto again;
1907 } else {
1908 /* Scanned the whole thing, give up. */
1909 return -1;
1910 }
1911 }
1912 bitmap_set(arena->map, n, npages);
1913
1914 arena->hint = end;
1915
1916 return n;
1917 }
1918
1919 #define COOKIE_PGSZ_CODE 0xf000000000000000ULL
1920 #define COOKIE_PGSZ_CODE_SHIFT 60ULL
1921
1922 static u64 pagesize_code(void)
1923 {
1924 switch (PAGE_SIZE) {
1925 default:
1926 case (8ULL * 1024ULL):
1927 return 0;
1928 case (64ULL * 1024ULL):
1929 return 1;
1930 case (512ULL * 1024ULL):
1931 return 2;
1932 case (4ULL * 1024ULL * 1024ULL):
1933 return 3;
1934 case (32ULL * 1024ULL * 1024ULL):
1935 return 4;
1936 case (256ULL * 1024ULL * 1024ULL):
1937 return 5;
1938 }
1939 }
1940
1941 static u64 make_cookie(u64 index, u64 pgsz_code, u64 page_offset)
1942 {
1943 return ((pgsz_code << COOKIE_PGSZ_CODE_SHIFT) |
1944 (index << PAGE_SHIFT) |
1945 page_offset);
1946 }
1947
1948 static u64 cookie_to_index(u64 cookie, unsigned long *shift)
1949 {
1950 u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT;
1951
1952 cookie &= ~COOKIE_PGSZ_CODE;
1953
1954 *shift = szcode * 3;
1955
1956 return (cookie >> (13ULL + (szcode * 3ULL)));
1957 }
1958
1959 static struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu,
1960 unsigned long npages)
1961 {
1962 long entry;
1963
1964 entry = arena_alloc(iommu, npages);
1965 if (unlikely(entry < 0))
1966 return NULL;
1967
1968 return iommu->page_table + entry;
1969 }
1970
1971 static u64 perm_to_mte(unsigned int map_perm)
1972 {
1973 u64 mte_base;
1974
1975 mte_base = pagesize_code();
1976
1977 if (map_perm & LDC_MAP_SHADOW) {
1978 if (map_perm & LDC_MAP_R)
1979 mte_base |= LDC_MTE_COPY_R;
1980 if (map_perm & LDC_MAP_W)
1981 mte_base |= LDC_MTE_COPY_W;
1982 }
1983 if (map_perm & LDC_MAP_DIRECT) {
1984 if (map_perm & LDC_MAP_R)
1985 mte_base |= LDC_MTE_READ;
1986 if (map_perm & LDC_MAP_W)
1987 mte_base |= LDC_MTE_WRITE;
1988 if (map_perm & LDC_MAP_X)
1989 mte_base |= LDC_MTE_EXEC;
1990 }
1991 if (map_perm & LDC_MAP_IO) {
1992 if (map_perm & LDC_MAP_R)
1993 mte_base |= LDC_MTE_IOMMU_R;
1994 if (map_perm & LDC_MAP_W)
1995 mte_base |= LDC_MTE_IOMMU_W;
1996 }
1997
1998 return mte_base;
1999 }
2000
2001 static int pages_in_region(unsigned long base, long len)
2002 {
2003 int count = 0;
2004
2005 do {
2006 unsigned long new = (base + PAGE_SIZE) & PAGE_MASK;
2007
2008 len -= (new - base);
2009 base = new;
2010 count++;
2011 } while (len > 0);
2012
2013 return count;
2014 }
2015
2016 struct cookie_state {
2017 struct ldc_mtable_entry *page_table;
2018 struct ldc_trans_cookie *cookies;
2019 u64 mte_base;
2020 u64 prev_cookie;
2021 u32 pte_idx;
2022 u32 nc;
2023 };
2024
2025 static void fill_cookies(struct cookie_state *sp, unsigned long pa,
2026 unsigned long off, unsigned long len)
2027 {
2028 do {
2029 unsigned long tlen, new = pa + PAGE_SIZE;
2030 u64 this_cookie;
2031
2032 sp->page_table[sp->pte_idx].mte = sp->mte_base | pa;
2033
2034 tlen = PAGE_SIZE;
2035 if (off)
2036 tlen = PAGE_SIZE - off;
2037 if (tlen > len)
2038 tlen = len;
2039
2040 this_cookie = make_cookie(sp->pte_idx,
2041 pagesize_code(), off);
2042
2043 off = 0;
2044
2045 if (this_cookie == sp->prev_cookie) {
2046 sp->cookies[sp->nc - 1].cookie_size += tlen;
2047 } else {
2048 sp->cookies[sp->nc].cookie_addr = this_cookie;
2049 sp->cookies[sp->nc].cookie_size = tlen;
2050 sp->nc++;
2051 }
2052 sp->prev_cookie = this_cookie + tlen;
2053
2054 sp->pte_idx++;
2055
2056 len -= tlen;
2057 pa = new;
2058 } while (len > 0);
2059 }
2060
2061 static int sg_count_one(struct scatterlist *sg)
2062 {
2063 unsigned long base = page_to_pfn(sg_page(sg)) << PAGE_SHIFT;
2064 long len = sg->length;
2065
2066 if ((sg->offset | len) & (8UL - 1))
2067 return -EFAULT;
2068
2069 return pages_in_region(base + sg->offset, len);
2070 }
2071
2072 static int sg_count_pages(struct scatterlist *sg, int num_sg)
2073 {
2074 int count;
2075 int i;
2076
2077 count = 0;
2078 for (i = 0; i < num_sg; i++) {
2079 int err = sg_count_one(sg + i);
2080 if (err < 0)
2081 return err;
2082 count += err;
2083 }
2084
2085 return count;
2086 }
2087
2088 int ldc_map_sg(struct ldc_channel *lp,
2089 struct scatterlist *sg, int num_sg,
2090 struct ldc_trans_cookie *cookies, int ncookies,
2091 unsigned int map_perm)
2092 {
2093 unsigned long i, npages, flags;
2094 struct ldc_mtable_entry *base;
2095 struct cookie_state state;
2096 struct ldc_iommu *iommu;
2097 int err;
2098
2099 if (map_perm & ~LDC_MAP_ALL)
2100 return -EINVAL;
2101
2102 err = sg_count_pages(sg, num_sg);
2103 if (err < 0)
2104 return err;
2105
2106 npages = err;
2107 if (err > ncookies)
2108 return -EMSGSIZE;
2109
2110 iommu = &lp->iommu;
2111
2112 spin_lock_irqsave(&iommu->lock, flags);
2113 base = alloc_npages(iommu, npages);
2114 spin_unlock_irqrestore(&iommu->lock, flags);
2115
2116 if (!base)
2117 return -ENOMEM;
2118
2119 state.page_table = iommu->page_table;
2120 state.cookies = cookies;
2121 state.mte_base = perm_to_mte(map_perm);
2122 state.prev_cookie = ~(u64)0;
2123 state.pte_idx = (base - iommu->page_table);
2124 state.nc = 0;
2125
2126 for (i = 0; i < num_sg; i++)
2127 fill_cookies(&state, page_to_pfn(sg_page(&sg[i])) << PAGE_SHIFT,
2128 sg[i].offset, sg[i].length);
2129
2130 return state.nc;
2131 }
2132 EXPORT_SYMBOL(ldc_map_sg);
2133
2134 int ldc_map_single(struct ldc_channel *lp,
2135 void *buf, unsigned int len,
2136 struct ldc_trans_cookie *cookies, int ncookies,
2137 unsigned int map_perm)
2138 {
2139 unsigned long npages, pa, flags;
2140 struct ldc_mtable_entry *base;
2141 struct cookie_state state;
2142 struct ldc_iommu *iommu;
2143
2144 if ((map_perm & ~LDC_MAP_ALL) || (ncookies < 1))
2145 return -EINVAL;
2146
2147 pa = __pa(buf);
2148 if ((pa | len) & (8UL - 1))
2149 return -EFAULT;
2150
2151 npages = pages_in_region(pa, len);
2152
2153 iommu = &lp->iommu;
2154
2155 spin_lock_irqsave(&iommu->lock, flags);
2156 base = alloc_npages(iommu, npages);
2157 spin_unlock_irqrestore(&iommu->lock, flags);
2158
2159 if (!base)
2160 return -ENOMEM;
2161
2162 state.page_table = iommu->page_table;
2163 state.cookies = cookies;
2164 state.mte_base = perm_to_mte(map_perm);
2165 state.prev_cookie = ~(u64)0;
2166 state.pte_idx = (base - iommu->page_table);
2167 state.nc = 0;
2168 fill_cookies(&state, (pa & PAGE_MASK), (pa & ~PAGE_MASK), len);
2169 BUG_ON(state.nc > ncookies);
2170
2171 return state.nc;
2172 }
2173 EXPORT_SYMBOL(ldc_map_single);
2174
2175 static void free_npages(unsigned long id, struct ldc_iommu *iommu,
2176 u64 cookie, u64 size)
2177 {
2178 struct iommu_arena *arena = &iommu->arena;
2179 unsigned long i, shift, index, npages;
2180 struct ldc_mtable_entry *base;
2181
2182 npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT;
2183 index = cookie_to_index(cookie, &shift);
2184 base = iommu->page_table + index;
2185
2186 BUG_ON(index > arena->limit ||
2187 (index + npages) > arena->limit);
2188
2189 for (i = 0; i < npages; i++) {
2190 if (base->cookie)
2191 sun4v_ldc_revoke(id, cookie + (i << shift),
2192 base->cookie);
2193 base->mte = 0;
2194 __clear_bit(index + i, arena->map);
2195 }
2196 }
2197
2198 void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies,
2199 int ncookies)
2200 {
2201 struct ldc_iommu *iommu = &lp->iommu;
2202 unsigned long flags;
2203 int i;
2204
2205 spin_lock_irqsave(&iommu->lock, flags);
2206 for (i = 0; i < ncookies; i++) {
2207 u64 addr = cookies[i].cookie_addr;
2208 u64 size = cookies[i].cookie_size;
2209
2210 free_npages(lp->id, iommu, addr, size);
2211 }
2212 spin_unlock_irqrestore(&iommu->lock, flags);
2213 }
2214 EXPORT_SYMBOL(ldc_unmap);
2215
2216 int ldc_copy(struct ldc_channel *lp, int copy_dir,
2217 void *buf, unsigned int len, unsigned long offset,
2218 struct ldc_trans_cookie *cookies, int ncookies)
2219 {
2220 unsigned int orig_len;
2221 unsigned long ra;
2222 int i;
2223
2224 if (copy_dir != LDC_COPY_IN && copy_dir != LDC_COPY_OUT) {
2225 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Bad copy_dir[%d]\n",
2226 lp->id, copy_dir);
2227 return -EINVAL;
2228 }
2229
2230 ra = __pa(buf);
2231 if ((ra | len | offset) & (8UL - 1)) {
2232 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Unaligned buffer "
2233 "ra[%lx] len[%x] offset[%lx]\n",
2234 lp->id, ra, len, offset);
2235 return -EFAULT;
2236 }
2237
2238 if (lp->hs_state != LDC_HS_COMPLETE ||
2239 (lp->flags & LDC_FLAG_RESET)) {
2240 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Link down hs_state[%x] "
2241 "flags[%x]\n", lp->id, lp->hs_state, lp->flags);
2242 return -ECONNRESET;
2243 }
2244
2245 orig_len = len;
2246 for (i = 0; i < ncookies; i++) {
2247 unsigned long cookie_raddr = cookies[i].cookie_addr;
2248 unsigned long this_len = cookies[i].cookie_size;
2249 unsigned long actual_len;
2250
2251 if (unlikely(offset)) {
2252 unsigned long this_off = offset;
2253
2254 if (this_off > this_len)
2255 this_off = this_len;
2256
2257 offset -= this_off;
2258 this_len -= this_off;
2259 if (!this_len)
2260 continue;
2261 cookie_raddr += this_off;
2262 }
2263
2264 if (this_len > len)
2265 this_len = len;
2266
2267 while (1) {
2268 unsigned long hv_err;
2269
2270 hv_err = sun4v_ldc_copy(lp->id, copy_dir,
2271 cookie_raddr, ra,
2272 this_len, &actual_len);
2273 if (unlikely(hv_err)) {
2274 printk(KERN_ERR PFX "ldc_copy: ID[%lu] "
2275 "HV error %lu\n",
2276 lp->id, hv_err);
2277 if (lp->hs_state != LDC_HS_COMPLETE ||
2278 (lp->flags & LDC_FLAG_RESET))
2279 return -ECONNRESET;
2280 else
2281 return -EFAULT;
2282 }
2283
2284 cookie_raddr += actual_len;
2285 ra += actual_len;
2286 len -= actual_len;
2287 if (actual_len == this_len)
2288 break;
2289
2290 this_len -= actual_len;
2291 }
2292
2293 if (!len)
2294 break;
2295 }
2296
2297 /* It is caller policy what to do about short copies.
2298 * For example, a networking driver can declare the
2299 * packet a runt and drop it.
2300 */
2301
2302 return orig_len - len;
2303 }
2304 EXPORT_SYMBOL(ldc_copy);
2305
2306 void *ldc_alloc_exp_dring(struct ldc_channel *lp, unsigned int len,
2307 struct ldc_trans_cookie *cookies, int *ncookies,
2308 unsigned int map_perm)
2309 {
2310 void *buf;
2311 int err;
2312
2313 if (len & (8UL - 1))
2314 return ERR_PTR(-EINVAL);
2315
2316 buf = kzalloc(len, GFP_KERNEL);
2317 if (!buf)
2318 return ERR_PTR(-ENOMEM);
2319
2320 err = ldc_map_single(lp, buf, len, cookies, *ncookies, map_perm);
2321 if (err < 0) {
2322 kfree(buf);
2323 return ERR_PTR(err);
2324 }
2325 *ncookies = err;
2326
2327 return buf;
2328 }
2329 EXPORT_SYMBOL(ldc_alloc_exp_dring);
2330
2331 void ldc_free_exp_dring(struct ldc_channel *lp, void *buf, unsigned int len,
2332 struct ldc_trans_cookie *cookies, int ncookies)
2333 {
2334 ldc_unmap(lp, cookies, ncookies);
2335 kfree(buf);
2336 }
2337 EXPORT_SYMBOL(ldc_free_exp_dring);
2338
2339 static int __init ldc_init(void)
2340 {
2341 unsigned long major, minor;
2342 struct mdesc_handle *hp;
2343 const u64 *v;
2344 int err;
2345 u64 mp;
2346
2347 hp = mdesc_grab();
2348 if (!hp)
2349 return -ENODEV;
2350
2351 mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
2352 err = -ENODEV;
2353 if (mp == MDESC_NODE_NULL)
2354 goto out;
2355
2356 v = mdesc_get_property(hp, mp, "domaining-enabled", NULL);
2357 if (!v)
2358 goto out;
2359
2360 major = 1;
2361 minor = 0;
2362 if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) {
2363 printk(KERN_INFO PFX "Could not register LDOM hvapi.\n");
2364 goto out;
2365 }
2366
2367 printk(KERN_INFO "%s", version);
2368
2369 if (!*v) {
2370 printk(KERN_INFO PFX "Domaining disabled.\n");
2371 goto out;
2372 }
2373 ldom_domaining_enabled = 1;
2374 err = 0;
2375
2376 out:
2377 mdesc_release(hp);
2378 return err;
2379 }
2380
2381 core_initcall(ldc_init);
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