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sparc64: prepare module_64.c for unification
[deliverable/linux.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/module.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
18 #include <asm/hypervisor.h>
19 #include <asm/iommu.h>
20 #include <asm/page.h>
21 #include <asm/ldc.h>
22 #include <asm/mdesc.h>
23
24 #define DRV_MODULE_NAME "ldc"
25 #define PFX DRV_MODULE_NAME ": "
26 #define DRV_MODULE_VERSION "1.1"
27 #define DRV_MODULE_RELDATE "July 22, 2008"
28
29 static char version[] __devinitdata =
30 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
31 #define LDC_PACKET_SIZE 64
32
33 /* Packet header layout for unreliable and reliable mode frames.
34 * When in RAW mode, packets are simply straight 64-byte payloads
35 * with no headers.
36 */
37 struct ldc_packet {
38 u8 type;
39 #define LDC_CTRL 0x01
40 #define LDC_DATA 0x02
41 #define LDC_ERR 0x10
42
43 u8 stype;
44 #define LDC_INFO 0x01
45 #define LDC_ACK 0x02
46 #define LDC_NACK 0x04
47
48 u8 ctrl;
49 #define LDC_VERS 0x01 /* Link Version */
50 #define LDC_RTS 0x02 /* Request To Send */
51 #define LDC_RTR 0x03 /* Ready To Receive */
52 #define LDC_RDX 0x04 /* Ready for Data eXchange */
53 #define LDC_CTRL_MSK 0x0f
54
55 u8 env;
56 #define LDC_LEN 0x3f
57 #define LDC_FRAG_MASK 0xc0
58 #define LDC_START 0x40
59 #define LDC_STOP 0x80
60
61 u32 seqid;
62
63 union {
64 u8 u_data[LDC_PACKET_SIZE - 8];
65 struct {
66 u32 pad;
67 u32 ackid;
68 u8 r_data[LDC_PACKET_SIZE - 8 - 8];
69 } r;
70 } u;
71 };
72
73 struct ldc_version {
74 u16 major;
75 u16 minor;
76 };
77
78 /* Ordered from largest major to lowest. */
79 static struct ldc_version ver_arr[] = {
80 { .major = 1, .minor = 0 },
81 };
82
83 #define LDC_DEFAULT_MTU (4 * LDC_PACKET_SIZE)
84 #define LDC_DEFAULT_NUM_ENTRIES (PAGE_SIZE / LDC_PACKET_SIZE)
85
86 struct ldc_channel;
87
88 struct ldc_mode_ops {
89 int (*write)(struct ldc_channel *, const void *, unsigned int);
90 int (*read)(struct ldc_channel *, void *, unsigned int);
91 };
92
93 static const struct ldc_mode_ops raw_ops;
94 static const struct ldc_mode_ops nonraw_ops;
95 static const struct ldc_mode_ops stream_ops;
96
97 int ldom_domaining_enabled;
98
99 struct ldc_iommu {
100 /* Protects arena alloc/free. */
101 spinlock_t lock;
102 struct iommu_arena arena;
103 struct ldc_mtable_entry *page_table;
104 };
105
106 struct ldc_channel {
107 /* Protects all operations that depend upon channel state. */
108 spinlock_t lock;
109
110 unsigned long id;
111
112 u8 *mssbuf;
113 u32 mssbuf_len;
114 u32 mssbuf_off;
115
116 struct ldc_packet *tx_base;
117 unsigned long tx_head;
118 unsigned long tx_tail;
119 unsigned long tx_num_entries;
120 unsigned long tx_ra;
121
122 unsigned long tx_acked;
123
124 struct ldc_packet *rx_base;
125 unsigned long rx_head;
126 unsigned long rx_tail;
127 unsigned long rx_num_entries;
128 unsigned long rx_ra;
129
130 u32 rcv_nxt;
131 u32 snd_nxt;
132
133 unsigned long chan_state;
134
135 struct ldc_channel_config cfg;
136 void *event_arg;
137
138 const struct ldc_mode_ops *mops;
139
140 struct ldc_iommu iommu;
141
142 struct ldc_version ver;
143
144 u8 hs_state;
145 #define LDC_HS_CLOSED 0x00
146 #define LDC_HS_OPEN 0x01
147 #define LDC_HS_GOTVERS 0x02
148 #define LDC_HS_SENTRTR 0x03
149 #define LDC_HS_GOTRTR 0x04
150 #define LDC_HS_COMPLETE 0x10
151
152 u8 flags;
153 #define LDC_FLAG_ALLOCED_QUEUES 0x01
154 #define LDC_FLAG_REGISTERED_QUEUES 0x02
155 #define LDC_FLAG_REGISTERED_IRQS 0x04
156 #define LDC_FLAG_RESET 0x10
157
158 u8 mss;
159 u8 state;
160
161 #define LDC_IRQ_NAME_MAX 32
162 char rx_irq_name[LDC_IRQ_NAME_MAX];
163 char tx_irq_name[LDC_IRQ_NAME_MAX];
164
165 struct hlist_head mh_list;
166
167 struct hlist_node list;
168 };
169
170 #define ldcdbg(TYPE, f, a...) \
171 do { if (lp->cfg.debug & LDC_DEBUG_##TYPE) \
172 printk(KERN_INFO PFX "ID[%lu] " f, lp->id, ## a); \
173 } while (0)
174
175 static const char *state_to_str(u8 state)
176 {
177 switch (state) {
178 case LDC_STATE_INVALID:
179 return "INVALID";
180 case LDC_STATE_INIT:
181 return "INIT";
182 case LDC_STATE_BOUND:
183 return "BOUND";
184 case LDC_STATE_READY:
185 return "READY";
186 case LDC_STATE_CONNECTED:
187 return "CONNECTED";
188 default:
189 return "<UNKNOWN>";
190 }
191 }
192
193 static void ldc_set_state(struct ldc_channel *lp, u8 state)
194 {
195 ldcdbg(STATE, "STATE (%s) --> (%s)\n",
196 state_to_str(lp->state),
197 state_to_str(state));
198
199 lp->state = state;
200 }
201
202 static unsigned long __advance(unsigned long off, unsigned long num_entries)
203 {
204 off += LDC_PACKET_SIZE;
205 if (off == (num_entries * LDC_PACKET_SIZE))
206 off = 0;
207
208 return off;
209 }
210
211 static unsigned long rx_advance(struct ldc_channel *lp, unsigned long off)
212 {
213 return __advance(off, lp->rx_num_entries);
214 }
215
216 static unsigned long tx_advance(struct ldc_channel *lp, unsigned long off)
217 {
218 return __advance(off, lp->tx_num_entries);
219 }
220
221 static struct ldc_packet *handshake_get_tx_packet(struct ldc_channel *lp,
222 unsigned long *new_tail)
223 {
224 struct ldc_packet *p;
225 unsigned long t;
226
227 t = tx_advance(lp, lp->tx_tail);
228 if (t == lp->tx_head)
229 return NULL;
230
231 *new_tail = t;
232
233 p = lp->tx_base;
234 return p + (lp->tx_tail / LDC_PACKET_SIZE);
235 }
236
237 /* When we are in reliable or stream mode, have to track the next packet
238 * we haven't gotten an ACK for in the TX queue using tx_acked. We have
239 * to be careful not to stomp over the queue past that point. During
240 * the handshake, we don't have TX data packets pending in the queue
241 * and that's why handshake_get_tx_packet() need not be mindful of
242 * lp->tx_acked.
243 */
244 static unsigned long head_for_data(struct ldc_channel *lp)
245 {
246 if (lp->cfg.mode == LDC_MODE_STREAM)
247 return lp->tx_acked;
248 return lp->tx_head;
249 }
250
251 static int tx_has_space_for(struct ldc_channel *lp, unsigned int size)
252 {
253 unsigned long limit, tail, new_tail, diff;
254 unsigned int mss;
255
256 limit = head_for_data(lp);
257 tail = lp->tx_tail;
258 new_tail = tx_advance(lp, tail);
259 if (new_tail == limit)
260 return 0;
261
262 if (limit > new_tail)
263 diff = limit - new_tail;
264 else
265 diff = (limit +
266 ((lp->tx_num_entries * LDC_PACKET_SIZE) - new_tail));
267 diff /= LDC_PACKET_SIZE;
268 mss = lp->mss;
269
270 if (diff * mss < size)
271 return 0;
272
273 return 1;
274 }
275
276 static struct ldc_packet *data_get_tx_packet(struct ldc_channel *lp,
277 unsigned long *new_tail)
278 {
279 struct ldc_packet *p;
280 unsigned long h, t;
281
282 h = head_for_data(lp);
283 t = tx_advance(lp, lp->tx_tail);
284 if (t == h)
285 return NULL;
286
287 *new_tail = t;
288
289 p = lp->tx_base;
290 return p + (lp->tx_tail / LDC_PACKET_SIZE);
291 }
292
293 static int set_tx_tail(struct ldc_channel *lp, unsigned long tail)
294 {
295 unsigned long orig_tail = lp->tx_tail;
296 int limit = 1000;
297
298 lp->tx_tail = tail;
299 while (limit-- > 0) {
300 unsigned long err;
301
302 err = sun4v_ldc_tx_set_qtail(lp->id, tail);
303 if (!err)
304 return 0;
305
306 if (err != HV_EWOULDBLOCK) {
307 lp->tx_tail = orig_tail;
308 return -EINVAL;
309 }
310 udelay(1);
311 }
312
313 lp->tx_tail = orig_tail;
314 return -EBUSY;
315 }
316
317 /* This just updates the head value in the hypervisor using
318 * a polling loop with a timeout. The caller takes care of
319 * upating software state representing the head change, if any.
320 */
321 static int __set_rx_head(struct ldc_channel *lp, unsigned long head)
322 {
323 int limit = 1000;
324
325 while (limit-- > 0) {
326 unsigned long err;
327
328 err = sun4v_ldc_rx_set_qhead(lp->id, head);
329 if (!err)
330 return 0;
331
332 if (err != HV_EWOULDBLOCK)
333 return -EINVAL;
334
335 udelay(1);
336 }
337
338 return -EBUSY;
339 }
340
341 static int send_tx_packet(struct ldc_channel *lp,
342 struct ldc_packet *p,
343 unsigned long new_tail)
344 {
345 BUG_ON(p != (lp->tx_base + (lp->tx_tail / LDC_PACKET_SIZE)));
346
347 return set_tx_tail(lp, new_tail);
348 }
349
350 static struct ldc_packet *handshake_compose_ctrl(struct ldc_channel *lp,
351 u8 stype, u8 ctrl,
352 void *data, int dlen,
353 unsigned long *new_tail)
354 {
355 struct ldc_packet *p = handshake_get_tx_packet(lp, new_tail);
356
357 if (p) {
358 memset(p, 0, sizeof(*p));
359 p->type = LDC_CTRL;
360 p->stype = stype;
361 p->ctrl = ctrl;
362 if (data)
363 memcpy(p->u.u_data, data, dlen);
364 }
365 return p;
366 }
367
368 static int start_handshake(struct ldc_channel *lp)
369 {
370 struct ldc_packet *p;
371 struct ldc_version *ver;
372 unsigned long new_tail;
373
374 ver = &ver_arr[0];
375
376 ldcdbg(HS, "SEND VER INFO maj[%u] min[%u]\n",
377 ver->major, ver->minor);
378
379 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
380 ver, sizeof(*ver), &new_tail);
381 if (p) {
382 int err = send_tx_packet(lp, p, new_tail);
383 if (!err)
384 lp->flags &= ~LDC_FLAG_RESET;
385 return err;
386 }
387 return -EBUSY;
388 }
389
390 static int send_version_nack(struct ldc_channel *lp,
391 u16 major, u16 minor)
392 {
393 struct ldc_packet *p;
394 struct ldc_version ver;
395 unsigned long new_tail;
396
397 ver.major = major;
398 ver.minor = minor;
399
400 p = handshake_compose_ctrl(lp, LDC_NACK, LDC_VERS,
401 &ver, sizeof(ver), &new_tail);
402 if (p) {
403 ldcdbg(HS, "SEND VER NACK maj[%u] min[%u]\n",
404 ver.major, ver.minor);
405
406 return send_tx_packet(lp, p, new_tail);
407 }
408 return -EBUSY;
409 }
410
411 static int send_version_ack(struct ldc_channel *lp,
412 struct ldc_version *vp)
413 {
414 struct ldc_packet *p;
415 unsigned long new_tail;
416
417 p = handshake_compose_ctrl(lp, LDC_ACK, LDC_VERS,
418 vp, sizeof(*vp), &new_tail);
419 if (p) {
420 ldcdbg(HS, "SEND VER ACK maj[%u] min[%u]\n",
421 vp->major, vp->minor);
422
423 return send_tx_packet(lp, p, new_tail);
424 }
425 return -EBUSY;
426 }
427
428 static int send_rts(struct ldc_channel *lp)
429 {
430 struct ldc_packet *p;
431 unsigned long new_tail;
432
433 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTS, NULL, 0,
434 &new_tail);
435 if (p) {
436 p->env = lp->cfg.mode;
437 p->seqid = 0;
438 lp->rcv_nxt = 0;
439
440 ldcdbg(HS, "SEND RTS env[0x%x] seqid[0x%x]\n",
441 p->env, p->seqid);
442
443 return send_tx_packet(lp, p, new_tail);
444 }
445 return -EBUSY;
446 }
447
448 static int send_rtr(struct ldc_channel *lp)
449 {
450 struct ldc_packet *p;
451 unsigned long new_tail;
452
453 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTR, NULL, 0,
454 &new_tail);
455 if (p) {
456 p->env = lp->cfg.mode;
457 p->seqid = 0;
458
459 ldcdbg(HS, "SEND RTR env[0x%x] seqid[0x%x]\n",
460 p->env, p->seqid);
461
462 return send_tx_packet(lp, p, new_tail);
463 }
464 return -EBUSY;
465 }
466
467 static int send_rdx(struct ldc_channel *lp)
468 {
469 struct ldc_packet *p;
470 unsigned long new_tail;
471
472 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RDX, NULL, 0,
473 &new_tail);
474 if (p) {
475 p->env = 0;
476 p->seqid = ++lp->snd_nxt;
477 p->u.r.ackid = lp->rcv_nxt;
478
479 ldcdbg(HS, "SEND RDX env[0x%x] seqid[0x%x] ackid[0x%x]\n",
480 p->env, p->seqid, p->u.r.ackid);
481
482 return send_tx_packet(lp, p, new_tail);
483 }
484 return -EBUSY;
485 }
486
487 static int send_data_nack(struct ldc_channel *lp, struct ldc_packet *data_pkt)
488 {
489 struct ldc_packet *p;
490 unsigned long new_tail;
491 int err;
492
493 p = data_get_tx_packet(lp, &new_tail);
494 if (!p)
495 return -EBUSY;
496 memset(p, 0, sizeof(*p));
497 p->type = data_pkt->type;
498 p->stype = LDC_NACK;
499 p->ctrl = data_pkt->ctrl & LDC_CTRL_MSK;
500 p->seqid = lp->snd_nxt + 1;
501 p->u.r.ackid = lp->rcv_nxt;
502
503 ldcdbg(HS, "SEND DATA NACK type[0x%x] ctl[0x%x] seq[0x%x] ack[0x%x]\n",
504 p->type, p->ctrl, p->seqid, p->u.r.ackid);
505
506 err = send_tx_packet(lp, p, new_tail);
507 if (!err)
508 lp->snd_nxt++;
509
510 return err;
511 }
512
513 static int ldc_abort(struct ldc_channel *lp)
514 {
515 unsigned long hv_err;
516
517 ldcdbg(STATE, "ABORT\n");
518
519 /* We report but do not act upon the hypervisor errors because
520 * there really isn't much we can do if they fail at this point.
521 */
522 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
523 if (hv_err)
524 printk(KERN_ERR PFX "ldc_abort: "
525 "sun4v_ldc_tx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
526 lp->id, lp->tx_ra, lp->tx_num_entries, hv_err);
527
528 hv_err = sun4v_ldc_tx_get_state(lp->id,
529 &lp->tx_head,
530 &lp->tx_tail,
531 &lp->chan_state);
532 if (hv_err)
533 printk(KERN_ERR PFX "ldc_abort: "
534 "sun4v_ldc_tx_get_state(%lx,...) failed, err=%lu\n",
535 lp->id, hv_err);
536
537 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
538 if (hv_err)
539 printk(KERN_ERR PFX "ldc_abort: "
540 "sun4v_ldc_rx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
541 lp->id, lp->rx_ra, lp->rx_num_entries, hv_err);
542
543 /* Refetch the RX queue state as well, because we could be invoked
544 * here in the queue processing context.
545 */
546 hv_err = sun4v_ldc_rx_get_state(lp->id,
547 &lp->rx_head,
548 &lp->rx_tail,
549 &lp->chan_state);
550 if (hv_err)
551 printk(KERN_ERR PFX "ldc_abort: "
552 "sun4v_ldc_rx_get_state(%lx,...) failed, err=%lu\n",
553 lp->id, hv_err);
554
555 return -ECONNRESET;
556 }
557
558 static struct ldc_version *find_by_major(u16 major)
559 {
560 struct ldc_version *ret = NULL;
561 int i;
562
563 for (i = 0; i < ARRAY_SIZE(ver_arr); i++) {
564 struct ldc_version *v = &ver_arr[i];
565 if (v->major <= major) {
566 ret = v;
567 break;
568 }
569 }
570 return ret;
571 }
572
573 static int process_ver_info(struct ldc_channel *lp, struct ldc_version *vp)
574 {
575 struct ldc_version *vap;
576 int err;
577
578 ldcdbg(HS, "GOT VERSION INFO major[%x] minor[%x]\n",
579 vp->major, vp->minor);
580
581 if (lp->hs_state == LDC_HS_GOTVERS) {
582 lp->hs_state = LDC_HS_OPEN;
583 memset(&lp->ver, 0, sizeof(lp->ver));
584 }
585
586 vap = find_by_major(vp->major);
587 if (!vap) {
588 err = send_version_nack(lp, 0, 0);
589 } else if (vap->major != vp->major) {
590 err = send_version_nack(lp, vap->major, vap->minor);
591 } else {
592 struct ldc_version ver = *vp;
593 if (ver.minor > vap->minor)
594 ver.minor = vap->minor;
595 err = send_version_ack(lp, &ver);
596 if (!err) {
597 lp->ver = ver;
598 lp->hs_state = LDC_HS_GOTVERS;
599 }
600 }
601 if (err)
602 return ldc_abort(lp);
603
604 return 0;
605 }
606
607 static int process_ver_ack(struct ldc_channel *lp, struct ldc_version *vp)
608 {
609 ldcdbg(HS, "GOT VERSION ACK major[%x] minor[%x]\n",
610 vp->major, vp->minor);
611
612 if (lp->hs_state == LDC_HS_GOTVERS) {
613 if (lp->ver.major != vp->major ||
614 lp->ver.minor != vp->minor)
615 return ldc_abort(lp);
616 } else {
617 lp->ver = *vp;
618 lp->hs_state = LDC_HS_GOTVERS;
619 }
620 if (send_rts(lp))
621 return ldc_abort(lp);
622 return 0;
623 }
624
625 static int process_ver_nack(struct ldc_channel *lp, struct ldc_version *vp)
626 {
627 struct ldc_version *vap;
628
629 if ((vp->major == 0 && vp->minor == 0) ||
630 !(vap = find_by_major(vp->major))) {
631 return ldc_abort(lp);
632 } else {
633 struct ldc_packet *p;
634 unsigned long new_tail;
635
636 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
637 vap, sizeof(*vap),
638 &new_tail);
639 if (p)
640 return send_tx_packet(lp, p, new_tail);
641 else
642 return ldc_abort(lp);
643 }
644 }
645
646 static int process_version(struct ldc_channel *lp,
647 struct ldc_packet *p)
648 {
649 struct ldc_version *vp;
650
651 vp = (struct ldc_version *) p->u.u_data;
652
653 switch (p->stype) {
654 case LDC_INFO:
655 return process_ver_info(lp, vp);
656
657 case LDC_ACK:
658 return process_ver_ack(lp, vp);
659
660 case LDC_NACK:
661 return process_ver_nack(lp, vp);
662
663 default:
664 return ldc_abort(lp);
665 }
666 }
667
668 static int process_rts(struct ldc_channel *lp,
669 struct ldc_packet *p)
670 {
671 ldcdbg(HS, "GOT RTS stype[%x] seqid[%x] env[%x]\n",
672 p->stype, p->seqid, p->env);
673
674 if (p->stype != LDC_INFO ||
675 lp->hs_state != LDC_HS_GOTVERS ||
676 p->env != lp->cfg.mode)
677 return ldc_abort(lp);
678
679 lp->snd_nxt = p->seqid;
680 lp->rcv_nxt = p->seqid;
681 lp->hs_state = LDC_HS_SENTRTR;
682 if (send_rtr(lp))
683 return ldc_abort(lp);
684
685 return 0;
686 }
687
688 static int process_rtr(struct ldc_channel *lp,
689 struct ldc_packet *p)
690 {
691 ldcdbg(HS, "GOT RTR stype[%x] seqid[%x] env[%x]\n",
692 p->stype, p->seqid, p->env);
693
694 if (p->stype != LDC_INFO ||
695 p->env != lp->cfg.mode)
696 return ldc_abort(lp);
697
698 lp->snd_nxt = p->seqid;
699 lp->hs_state = LDC_HS_COMPLETE;
700 ldc_set_state(lp, LDC_STATE_CONNECTED);
701 send_rdx(lp);
702
703 return LDC_EVENT_UP;
704 }
705
706 static int rx_seq_ok(struct ldc_channel *lp, u32 seqid)
707 {
708 return lp->rcv_nxt + 1 == seqid;
709 }
710
711 static int process_rdx(struct ldc_channel *lp,
712 struct ldc_packet *p)
713 {
714 ldcdbg(HS, "GOT RDX stype[%x] seqid[%x] env[%x] ackid[%x]\n",
715 p->stype, p->seqid, p->env, p->u.r.ackid);
716
717 if (p->stype != LDC_INFO ||
718 !(rx_seq_ok(lp, p->seqid)))
719 return ldc_abort(lp);
720
721 lp->rcv_nxt = p->seqid;
722
723 lp->hs_state = LDC_HS_COMPLETE;
724 ldc_set_state(lp, LDC_STATE_CONNECTED);
725
726 return LDC_EVENT_UP;
727 }
728
729 static int process_control_frame(struct ldc_channel *lp,
730 struct ldc_packet *p)
731 {
732 switch (p->ctrl) {
733 case LDC_VERS:
734 return process_version(lp, p);
735
736 case LDC_RTS:
737 return process_rts(lp, p);
738
739 case LDC_RTR:
740 return process_rtr(lp, p);
741
742 case LDC_RDX:
743 return process_rdx(lp, p);
744
745 default:
746 return ldc_abort(lp);
747 }
748 }
749
750 static int process_error_frame(struct ldc_channel *lp,
751 struct ldc_packet *p)
752 {
753 return ldc_abort(lp);
754 }
755
756 static int process_data_ack(struct ldc_channel *lp,
757 struct ldc_packet *ack)
758 {
759 unsigned long head = lp->tx_acked;
760 u32 ackid = ack->u.r.ackid;
761
762 while (1) {
763 struct ldc_packet *p = lp->tx_base + (head / LDC_PACKET_SIZE);
764
765 head = tx_advance(lp, head);
766
767 if (p->seqid == ackid) {
768 lp->tx_acked = head;
769 return 0;
770 }
771 if (head == lp->tx_tail)
772 return ldc_abort(lp);
773 }
774
775 return 0;
776 }
777
778 static void send_events(struct ldc_channel *lp, unsigned int event_mask)
779 {
780 if (event_mask & LDC_EVENT_RESET)
781 lp->cfg.event(lp->event_arg, LDC_EVENT_RESET);
782 if (event_mask & LDC_EVENT_UP)
783 lp->cfg.event(lp->event_arg, LDC_EVENT_UP);
784 if (event_mask & LDC_EVENT_DATA_READY)
785 lp->cfg.event(lp->event_arg, LDC_EVENT_DATA_READY);
786 }
787
788 static irqreturn_t ldc_rx(int irq, void *dev_id)
789 {
790 struct ldc_channel *lp = dev_id;
791 unsigned long orig_state, hv_err, flags;
792 unsigned int event_mask;
793
794 spin_lock_irqsave(&lp->lock, flags);
795
796 orig_state = lp->chan_state;
797 hv_err = sun4v_ldc_rx_get_state(lp->id,
798 &lp->rx_head,
799 &lp->rx_tail,
800 &lp->chan_state);
801
802 ldcdbg(RX, "RX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
803 orig_state, lp->chan_state, lp->rx_head, lp->rx_tail);
804
805 event_mask = 0;
806
807 if (lp->cfg.mode == LDC_MODE_RAW &&
808 lp->chan_state == LDC_CHANNEL_UP) {
809 lp->hs_state = LDC_HS_COMPLETE;
810 ldc_set_state(lp, LDC_STATE_CONNECTED);
811
812 event_mask |= LDC_EVENT_UP;
813
814 orig_state = lp->chan_state;
815 }
816
817 /* If we are in reset state, flush the RX queue and ignore
818 * everything.
819 */
820 if (lp->flags & LDC_FLAG_RESET) {
821 (void) __set_rx_head(lp, lp->rx_tail);
822 goto out;
823 }
824
825 /* Once we finish the handshake, we let the ldc_read()
826 * paths do all of the control frame and state management.
827 * Just trigger the callback.
828 */
829 if (lp->hs_state == LDC_HS_COMPLETE) {
830 handshake_complete:
831 if (lp->chan_state != orig_state) {
832 unsigned int event = LDC_EVENT_RESET;
833
834 if (lp->chan_state == LDC_CHANNEL_UP)
835 event = LDC_EVENT_UP;
836
837 event_mask |= event;
838 }
839 if (lp->rx_head != lp->rx_tail)
840 event_mask |= LDC_EVENT_DATA_READY;
841
842 goto out;
843 }
844
845 if (lp->chan_state != orig_state)
846 goto out;
847
848 while (lp->rx_head != lp->rx_tail) {
849 struct ldc_packet *p;
850 unsigned long new;
851 int err;
852
853 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
854
855 switch (p->type) {
856 case LDC_CTRL:
857 err = process_control_frame(lp, p);
858 if (err > 0)
859 event_mask |= err;
860 break;
861
862 case LDC_DATA:
863 event_mask |= LDC_EVENT_DATA_READY;
864 err = 0;
865 break;
866
867 case LDC_ERR:
868 err = process_error_frame(lp, p);
869 break;
870
871 default:
872 err = ldc_abort(lp);
873 break;
874 }
875
876 if (err < 0)
877 break;
878
879 new = lp->rx_head;
880 new += LDC_PACKET_SIZE;
881 if (new == (lp->rx_num_entries * LDC_PACKET_SIZE))
882 new = 0;
883 lp->rx_head = new;
884
885 err = __set_rx_head(lp, new);
886 if (err < 0) {
887 (void) ldc_abort(lp);
888 break;
889 }
890 if (lp->hs_state == LDC_HS_COMPLETE)
891 goto handshake_complete;
892 }
893
894 out:
895 spin_unlock_irqrestore(&lp->lock, flags);
896
897 send_events(lp, event_mask);
898
899 return IRQ_HANDLED;
900 }
901
902 static irqreturn_t ldc_tx(int irq, void *dev_id)
903 {
904 struct ldc_channel *lp = dev_id;
905 unsigned long flags, hv_err, orig_state;
906 unsigned int event_mask = 0;
907
908 spin_lock_irqsave(&lp->lock, flags);
909
910 orig_state = lp->chan_state;
911 hv_err = sun4v_ldc_tx_get_state(lp->id,
912 &lp->tx_head,
913 &lp->tx_tail,
914 &lp->chan_state);
915
916 ldcdbg(TX, " TX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
917 orig_state, lp->chan_state, lp->tx_head, lp->tx_tail);
918
919 if (lp->cfg.mode == LDC_MODE_RAW &&
920 lp->chan_state == LDC_CHANNEL_UP) {
921 lp->hs_state = LDC_HS_COMPLETE;
922 ldc_set_state(lp, LDC_STATE_CONNECTED);
923
924 event_mask |= LDC_EVENT_UP;
925 }
926
927 spin_unlock_irqrestore(&lp->lock, flags);
928
929 send_events(lp, event_mask);
930
931 return IRQ_HANDLED;
932 }
933
934 /* XXX ldc_alloc() and ldc_free() needs to run under a mutex so
935 * XXX that addition and removal from the ldc_channel_list has
936 * XXX atomicity, otherwise the __ldc_channel_exists() check is
937 * XXX totally pointless as another thread can slip into ldc_alloc()
938 * XXX and add a channel with the same ID. There also needs to be
939 * XXX a spinlock for ldc_channel_list.
940 */
941 static HLIST_HEAD(ldc_channel_list);
942
943 static int __ldc_channel_exists(unsigned long id)
944 {
945 struct ldc_channel *lp;
946 struct hlist_node *n;
947
948 hlist_for_each_entry(lp, n, &ldc_channel_list, list) {
949 if (lp->id == id)
950 return 1;
951 }
952 return 0;
953 }
954
955 static int alloc_queue(const char *name, unsigned long num_entries,
956 struct ldc_packet **base, unsigned long *ra)
957 {
958 unsigned long size, order;
959 void *q;
960
961 size = num_entries * LDC_PACKET_SIZE;
962 order = get_order(size);
963
964 q = (void *) __get_free_pages(GFP_KERNEL, order);
965 if (!q) {
966 printk(KERN_ERR PFX "Alloc of %s queue failed with "
967 "size=%lu order=%lu\n", name, size, order);
968 return -ENOMEM;
969 }
970
971 memset(q, 0, PAGE_SIZE << order);
972
973 *base = q;
974 *ra = __pa(q);
975
976 return 0;
977 }
978
979 static void free_queue(unsigned long num_entries, struct ldc_packet *q)
980 {
981 unsigned long size, order;
982
983 if (!q)
984 return;
985
986 size = num_entries * LDC_PACKET_SIZE;
987 order = get_order(size);
988
989 free_pages((unsigned long)q, order);
990 }
991
992 /* XXX Make this configurable... XXX */
993 #define LDC_IOTABLE_SIZE (8 * 1024)
994
995 static int ldc_iommu_init(struct ldc_channel *lp)
996 {
997 unsigned long sz, num_tsb_entries, tsbsize, order;
998 struct ldc_iommu *iommu = &lp->iommu;
999 struct ldc_mtable_entry *table;
1000 unsigned long hv_err;
1001 int err;
1002
1003 num_tsb_entries = LDC_IOTABLE_SIZE;
1004 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1005
1006 spin_lock_init(&iommu->lock);
1007
1008 sz = num_tsb_entries / 8;
1009 sz = (sz + 7UL) & ~7UL;
1010 iommu->arena.map = kzalloc(sz, GFP_KERNEL);
1011 if (!iommu->arena.map) {
1012 printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz);
1013 return -ENOMEM;
1014 }
1015
1016 iommu->arena.limit = num_tsb_entries;
1017
1018 order = get_order(tsbsize);
1019
1020 table = (struct ldc_mtable_entry *)
1021 __get_free_pages(GFP_KERNEL, order);
1022 err = -ENOMEM;
1023 if (!table) {
1024 printk(KERN_ERR PFX "Alloc of MTE table failed, "
1025 "size=%lu order=%lu\n", tsbsize, order);
1026 goto out_free_map;
1027 }
1028
1029 memset(table, 0, PAGE_SIZE << order);
1030
1031 iommu->page_table = table;
1032
1033 hv_err = sun4v_ldc_set_map_table(lp->id, __pa(table),
1034 num_tsb_entries);
1035 err = -EINVAL;
1036 if (hv_err)
1037 goto out_free_table;
1038
1039 return 0;
1040
1041 out_free_table:
1042 free_pages((unsigned long) table, order);
1043 iommu->page_table = NULL;
1044
1045 out_free_map:
1046 kfree(iommu->arena.map);
1047 iommu->arena.map = NULL;
1048
1049 return err;
1050 }
1051
1052 static void ldc_iommu_release(struct ldc_channel *lp)
1053 {
1054 struct ldc_iommu *iommu = &lp->iommu;
1055 unsigned long num_tsb_entries, tsbsize, order;
1056
1057 (void) sun4v_ldc_set_map_table(lp->id, 0, 0);
1058
1059 num_tsb_entries = iommu->arena.limit;
1060 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1061 order = get_order(tsbsize);
1062
1063 free_pages((unsigned long) iommu->page_table, order);
1064 iommu->page_table = NULL;
1065
1066 kfree(iommu->arena.map);
1067 iommu->arena.map = NULL;
1068 }
1069
1070 struct ldc_channel *ldc_alloc(unsigned long id,
1071 const struct ldc_channel_config *cfgp,
1072 void *event_arg)
1073 {
1074 struct ldc_channel *lp;
1075 const struct ldc_mode_ops *mops;
1076 unsigned long dummy1, dummy2, hv_err;
1077 u8 mss, *mssbuf;
1078 int err;
1079
1080 err = -ENODEV;
1081 if (!ldom_domaining_enabled)
1082 goto out_err;
1083
1084 err = -EINVAL;
1085 if (!cfgp)
1086 goto out_err;
1087
1088 switch (cfgp->mode) {
1089 case LDC_MODE_RAW:
1090 mops = &raw_ops;
1091 mss = LDC_PACKET_SIZE;
1092 break;
1093
1094 case LDC_MODE_UNRELIABLE:
1095 mops = &nonraw_ops;
1096 mss = LDC_PACKET_SIZE - 8;
1097 break;
1098
1099 case LDC_MODE_STREAM:
1100 mops = &stream_ops;
1101 mss = LDC_PACKET_SIZE - 8 - 8;
1102 break;
1103
1104 default:
1105 goto out_err;
1106 }
1107
1108 if (!cfgp->event || !event_arg || !cfgp->rx_irq || !cfgp->tx_irq)
1109 goto out_err;
1110
1111 hv_err = sun4v_ldc_tx_qinfo(id, &dummy1, &dummy2);
1112 err = -ENODEV;
1113 if (hv_err == HV_ECHANNEL)
1114 goto out_err;
1115
1116 err = -EEXIST;
1117 if (__ldc_channel_exists(id))
1118 goto out_err;
1119
1120 mssbuf = NULL;
1121
1122 lp = kzalloc(sizeof(*lp), GFP_KERNEL);
1123 err = -ENOMEM;
1124 if (!lp)
1125 goto out_err;
1126
1127 spin_lock_init(&lp->lock);
1128
1129 lp->id = id;
1130
1131 err = ldc_iommu_init(lp);
1132 if (err)
1133 goto out_free_ldc;
1134
1135 lp->mops = mops;
1136 lp->mss = mss;
1137
1138 lp->cfg = *cfgp;
1139 if (!lp->cfg.mtu)
1140 lp->cfg.mtu = LDC_DEFAULT_MTU;
1141
1142 if (lp->cfg.mode == LDC_MODE_STREAM) {
1143 mssbuf = kzalloc(lp->cfg.mtu, GFP_KERNEL);
1144 if (!mssbuf) {
1145 err = -ENOMEM;
1146 goto out_free_iommu;
1147 }
1148 lp->mssbuf = mssbuf;
1149 }
1150
1151 lp->event_arg = event_arg;
1152
1153 /* XXX allow setting via ldc_channel_config to override defaults
1154 * XXX or use some formula based upon mtu
1155 */
1156 lp->tx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1157 lp->rx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1158
1159 err = alloc_queue("TX", lp->tx_num_entries,
1160 &lp->tx_base, &lp->tx_ra);
1161 if (err)
1162 goto out_free_mssbuf;
1163
1164 err = alloc_queue("RX", lp->rx_num_entries,
1165 &lp->rx_base, &lp->rx_ra);
1166 if (err)
1167 goto out_free_txq;
1168
1169 lp->flags |= LDC_FLAG_ALLOCED_QUEUES;
1170
1171 lp->hs_state = LDC_HS_CLOSED;
1172 ldc_set_state(lp, LDC_STATE_INIT);
1173
1174 INIT_HLIST_NODE(&lp->list);
1175 hlist_add_head(&lp->list, &ldc_channel_list);
1176
1177 INIT_HLIST_HEAD(&lp->mh_list);
1178
1179 return lp;
1180
1181 out_free_txq:
1182 free_queue(lp->tx_num_entries, lp->tx_base);
1183
1184 out_free_mssbuf:
1185 if (mssbuf)
1186 kfree(mssbuf);
1187
1188 out_free_iommu:
1189 ldc_iommu_release(lp);
1190
1191 out_free_ldc:
1192 kfree(lp);
1193
1194 out_err:
1195 return ERR_PTR(err);
1196 }
1197 EXPORT_SYMBOL(ldc_alloc);
1198
1199 void ldc_free(struct ldc_channel *lp)
1200 {
1201 if (lp->flags & LDC_FLAG_REGISTERED_IRQS) {
1202 free_irq(lp->cfg.rx_irq, lp);
1203 free_irq(lp->cfg.tx_irq, lp);
1204 }
1205
1206 if (lp->flags & LDC_FLAG_REGISTERED_QUEUES) {
1207 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1208 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1209 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1210 }
1211 if (lp->flags & LDC_FLAG_ALLOCED_QUEUES) {
1212 free_queue(lp->tx_num_entries, lp->tx_base);
1213 free_queue(lp->rx_num_entries, lp->rx_base);
1214 lp->flags &= ~LDC_FLAG_ALLOCED_QUEUES;
1215 }
1216
1217 hlist_del(&lp->list);
1218
1219 if (lp->mssbuf)
1220 kfree(lp->mssbuf);
1221
1222 ldc_iommu_release(lp);
1223
1224 kfree(lp);
1225 }
1226 EXPORT_SYMBOL(ldc_free);
1227
1228 /* Bind the channel. This registers the LDC queues with
1229 * the hypervisor and puts the channel into a pseudo-listening
1230 * state. This does not initiate a handshake, ldc_connect() does
1231 * that.
1232 */
1233 int ldc_bind(struct ldc_channel *lp, const char *name)
1234 {
1235 unsigned long hv_err, flags;
1236 int err = -EINVAL;
1237
1238 if (!name ||
1239 (lp->state != LDC_STATE_INIT))
1240 return -EINVAL;
1241
1242 snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name);
1243 snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name);
1244
1245 err = request_irq(lp->cfg.rx_irq, ldc_rx,
1246 IRQF_SAMPLE_RANDOM | IRQF_SHARED,
1247 lp->rx_irq_name, lp);
1248 if (err)
1249 return err;
1250
1251 err = request_irq(lp->cfg.tx_irq, ldc_tx,
1252 IRQF_SAMPLE_RANDOM | IRQF_SHARED,
1253 lp->tx_irq_name, lp);
1254 if (err) {
1255 free_irq(lp->cfg.rx_irq, lp);
1256 return err;
1257 }
1258
1259
1260 spin_lock_irqsave(&lp->lock, flags);
1261
1262 enable_irq(lp->cfg.rx_irq);
1263 enable_irq(lp->cfg.tx_irq);
1264
1265 lp->flags |= LDC_FLAG_REGISTERED_IRQS;
1266
1267 err = -ENODEV;
1268 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1269 if (hv_err)
1270 goto out_free_irqs;
1271
1272 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1273 if (hv_err)
1274 goto out_free_irqs;
1275
1276 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1277 if (hv_err)
1278 goto out_unmap_tx;
1279
1280 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1281 if (hv_err)
1282 goto out_unmap_tx;
1283
1284 lp->flags |= LDC_FLAG_REGISTERED_QUEUES;
1285
1286 hv_err = sun4v_ldc_tx_get_state(lp->id,
1287 &lp->tx_head,
1288 &lp->tx_tail,
1289 &lp->chan_state);
1290 err = -EBUSY;
1291 if (hv_err)
1292 goto out_unmap_rx;
1293
1294 lp->tx_acked = lp->tx_head;
1295
1296 lp->hs_state = LDC_HS_OPEN;
1297 ldc_set_state(lp, LDC_STATE_BOUND);
1298
1299 spin_unlock_irqrestore(&lp->lock, flags);
1300
1301 return 0;
1302
1303 out_unmap_rx:
1304 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1305 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1306
1307 out_unmap_tx:
1308 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1309
1310 out_free_irqs:
1311 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
1312 free_irq(lp->cfg.tx_irq, lp);
1313 free_irq(lp->cfg.rx_irq, lp);
1314
1315 spin_unlock_irqrestore(&lp->lock, flags);
1316
1317 return err;
1318 }
1319 EXPORT_SYMBOL(ldc_bind);
1320
1321 int ldc_connect(struct ldc_channel *lp)
1322 {
1323 unsigned long flags;
1324 int err;
1325
1326 if (lp->cfg.mode == LDC_MODE_RAW)
1327 return -EINVAL;
1328
1329 spin_lock_irqsave(&lp->lock, flags);
1330
1331 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1332 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES) ||
1333 lp->hs_state != LDC_HS_OPEN)
1334 err = -EINVAL;
1335 else
1336 err = start_handshake(lp);
1337
1338 spin_unlock_irqrestore(&lp->lock, flags);
1339
1340 return err;
1341 }
1342 EXPORT_SYMBOL(ldc_connect);
1343
1344 int ldc_disconnect(struct ldc_channel *lp)
1345 {
1346 unsigned long hv_err, flags;
1347 int err;
1348
1349 if (lp->cfg.mode == LDC_MODE_RAW)
1350 return -EINVAL;
1351
1352 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1353 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES))
1354 return -EINVAL;
1355
1356 spin_lock_irqsave(&lp->lock, flags);
1357
1358 err = -ENODEV;
1359 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1360 if (hv_err)
1361 goto out_err;
1362
1363 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1364 if (hv_err)
1365 goto out_err;
1366
1367 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1368 if (hv_err)
1369 goto out_err;
1370
1371 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1372 if (hv_err)
1373 goto out_err;
1374
1375 ldc_set_state(lp, LDC_STATE_BOUND);
1376 lp->hs_state = LDC_HS_OPEN;
1377 lp->flags |= LDC_FLAG_RESET;
1378
1379 spin_unlock_irqrestore(&lp->lock, flags);
1380
1381 return 0;
1382
1383 out_err:
1384 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1385 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1386 free_irq(lp->cfg.tx_irq, lp);
1387 free_irq(lp->cfg.rx_irq, lp);
1388 lp->flags &= ~(LDC_FLAG_REGISTERED_IRQS |
1389 LDC_FLAG_REGISTERED_QUEUES);
1390 ldc_set_state(lp, LDC_STATE_INIT);
1391
1392 spin_unlock_irqrestore(&lp->lock, flags);
1393
1394 return err;
1395 }
1396 EXPORT_SYMBOL(ldc_disconnect);
1397
1398 int ldc_state(struct ldc_channel *lp)
1399 {
1400 return lp->state;
1401 }
1402 EXPORT_SYMBOL(ldc_state);
1403
1404 static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size)
1405 {
1406 struct ldc_packet *p;
1407 unsigned long new_tail;
1408 int err;
1409
1410 if (size > LDC_PACKET_SIZE)
1411 return -EMSGSIZE;
1412
1413 p = data_get_tx_packet(lp, &new_tail);
1414 if (!p)
1415 return -EAGAIN;
1416
1417 memcpy(p, buf, size);
1418
1419 err = send_tx_packet(lp, p, new_tail);
1420 if (!err)
1421 err = size;
1422
1423 return err;
1424 }
1425
1426 static int read_raw(struct ldc_channel *lp, void *buf, unsigned int size)
1427 {
1428 struct ldc_packet *p;
1429 unsigned long hv_err, new;
1430 int err;
1431
1432 if (size < LDC_PACKET_SIZE)
1433 return -EINVAL;
1434
1435 hv_err = sun4v_ldc_rx_get_state(lp->id,
1436 &lp->rx_head,
1437 &lp->rx_tail,
1438 &lp->chan_state);
1439 if (hv_err)
1440 return ldc_abort(lp);
1441
1442 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1443 lp->chan_state == LDC_CHANNEL_RESETTING)
1444 return -ECONNRESET;
1445
1446 if (lp->rx_head == lp->rx_tail)
1447 return 0;
1448
1449 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
1450 memcpy(buf, p, LDC_PACKET_SIZE);
1451
1452 new = rx_advance(lp, lp->rx_head);
1453 lp->rx_head = new;
1454
1455 err = __set_rx_head(lp, new);
1456 if (err < 0)
1457 err = -ECONNRESET;
1458 else
1459 err = LDC_PACKET_SIZE;
1460
1461 return err;
1462 }
1463
1464 static const struct ldc_mode_ops raw_ops = {
1465 .write = write_raw,
1466 .read = read_raw,
1467 };
1468
1469 static int write_nonraw(struct ldc_channel *lp, const void *buf,
1470 unsigned int size)
1471 {
1472 unsigned long hv_err, tail;
1473 unsigned int copied;
1474 u32 seq;
1475 int err;
1476
1477 hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail,
1478 &lp->chan_state);
1479 if (unlikely(hv_err))
1480 return -EBUSY;
1481
1482 if (unlikely(lp->chan_state != LDC_CHANNEL_UP))
1483 return ldc_abort(lp);
1484
1485 if (!tx_has_space_for(lp, size))
1486 return -EAGAIN;
1487
1488 seq = lp->snd_nxt;
1489 copied = 0;
1490 tail = lp->tx_tail;
1491 while (copied < size) {
1492 struct ldc_packet *p = lp->tx_base + (tail / LDC_PACKET_SIZE);
1493 u8 *data = ((lp->cfg.mode == LDC_MODE_UNRELIABLE) ?
1494 p->u.u_data :
1495 p->u.r.r_data);
1496 int data_len;
1497
1498 p->type = LDC_DATA;
1499 p->stype = LDC_INFO;
1500 p->ctrl = 0;
1501
1502 data_len = size - copied;
1503 if (data_len > lp->mss)
1504 data_len = lp->mss;
1505
1506 BUG_ON(data_len > LDC_LEN);
1507
1508 p->env = (data_len |
1509 (copied == 0 ? LDC_START : 0) |
1510 (data_len == size - copied ? LDC_STOP : 0));
1511
1512 p->seqid = ++seq;
1513
1514 ldcdbg(DATA, "SENT DATA [%02x:%02x:%02x:%02x:%08x]\n",
1515 p->type,
1516 p->stype,
1517 p->ctrl,
1518 p->env,
1519 p->seqid);
1520
1521 memcpy(data, buf, data_len);
1522 buf += data_len;
1523 copied += data_len;
1524
1525 tail = tx_advance(lp, tail);
1526 }
1527
1528 err = set_tx_tail(lp, tail);
1529 if (!err) {
1530 lp->snd_nxt = seq;
1531 err = size;
1532 }
1533
1534 return err;
1535 }
1536
1537 static int rx_bad_seq(struct ldc_channel *lp, struct ldc_packet *p,
1538 struct ldc_packet *first_frag)
1539 {
1540 int err;
1541
1542 if (first_frag)
1543 lp->rcv_nxt = first_frag->seqid - 1;
1544
1545 err = send_data_nack(lp, p);
1546 if (err)
1547 return err;
1548
1549 err = __set_rx_head(lp, lp->rx_tail);
1550 if (err < 0)
1551 return ldc_abort(lp);
1552
1553 return 0;
1554 }
1555
1556 static int data_ack_nack(struct ldc_channel *lp, struct ldc_packet *p)
1557 {
1558 if (p->stype & LDC_ACK) {
1559 int err = process_data_ack(lp, p);
1560 if (err)
1561 return err;
1562 }
1563 if (p->stype & LDC_NACK)
1564 return ldc_abort(lp);
1565
1566 return 0;
1567 }
1568
1569 static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head)
1570 {
1571 unsigned long dummy;
1572 int limit = 1000;
1573
1574 ldcdbg(DATA, "DATA WAIT cur_head[%lx] rx_head[%lx] rx_tail[%lx]\n",
1575 cur_head, lp->rx_head, lp->rx_tail);
1576 while (limit-- > 0) {
1577 unsigned long hv_err;
1578
1579 hv_err = sun4v_ldc_rx_get_state(lp->id,
1580 &dummy,
1581 &lp->rx_tail,
1582 &lp->chan_state);
1583 if (hv_err)
1584 return ldc_abort(lp);
1585
1586 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1587 lp->chan_state == LDC_CHANNEL_RESETTING)
1588 return -ECONNRESET;
1589
1590 if (cur_head != lp->rx_tail) {
1591 ldcdbg(DATA, "DATA WAIT DONE "
1592 "head[%lx] tail[%lx] chan_state[%lx]\n",
1593 dummy, lp->rx_tail, lp->chan_state);
1594 return 0;
1595 }
1596
1597 udelay(1);
1598 }
1599 return -EAGAIN;
1600 }
1601
1602 static int rx_set_head(struct ldc_channel *lp, unsigned long head)
1603 {
1604 int err = __set_rx_head(lp, head);
1605
1606 if (err < 0)
1607 return ldc_abort(lp);
1608
1609 lp->rx_head = head;
1610 return 0;
1611 }
1612
1613 static void send_data_ack(struct ldc_channel *lp)
1614 {
1615 unsigned long new_tail;
1616 struct ldc_packet *p;
1617
1618 p = data_get_tx_packet(lp, &new_tail);
1619 if (likely(p)) {
1620 int err;
1621
1622 memset(p, 0, sizeof(*p));
1623 p->type = LDC_DATA;
1624 p->stype = LDC_ACK;
1625 p->ctrl = 0;
1626 p->seqid = lp->snd_nxt + 1;
1627 p->u.r.ackid = lp->rcv_nxt;
1628
1629 err = send_tx_packet(lp, p, new_tail);
1630 if (!err)
1631 lp->snd_nxt++;
1632 }
1633 }
1634
1635 static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
1636 {
1637 struct ldc_packet *first_frag;
1638 unsigned long hv_err, new;
1639 int err, copied;
1640
1641 hv_err = sun4v_ldc_rx_get_state(lp->id,
1642 &lp->rx_head,
1643 &lp->rx_tail,
1644 &lp->chan_state);
1645 if (hv_err)
1646 return ldc_abort(lp);
1647
1648 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1649 lp->chan_state == LDC_CHANNEL_RESETTING)
1650 return -ECONNRESET;
1651
1652 if (lp->rx_head == lp->rx_tail)
1653 return 0;
1654
1655 first_frag = NULL;
1656 copied = err = 0;
1657 new = lp->rx_head;
1658 while (1) {
1659 struct ldc_packet *p;
1660 int pkt_len;
1661
1662 BUG_ON(new == lp->rx_tail);
1663 p = lp->rx_base + (new / LDC_PACKET_SIZE);
1664
1665 ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x:%08x] "
1666 "rcv_nxt[%08x]\n",
1667 p->type,
1668 p->stype,
1669 p->ctrl,
1670 p->env,
1671 p->seqid,
1672 p->u.r.ackid,
1673 lp->rcv_nxt);
1674
1675 if (unlikely(!rx_seq_ok(lp, p->seqid))) {
1676 err = rx_bad_seq(lp, p, first_frag);
1677 copied = 0;
1678 break;
1679 }
1680
1681 if (p->type & LDC_CTRL) {
1682 err = process_control_frame(lp, p);
1683 if (err < 0)
1684 break;
1685 err = 0;
1686 }
1687
1688 lp->rcv_nxt = p->seqid;
1689
1690 if (!(p->type & LDC_DATA)) {
1691 new = rx_advance(lp, new);
1692 goto no_data;
1693 }
1694 if (p->stype & (LDC_ACK | LDC_NACK)) {
1695 err = data_ack_nack(lp, p);
1696 if (err)
1697 break;
1698 }
1699 if (!(p->stype & LDC_INFO)) {
1700 new = rx_advance(lp, new);
1701 err = rx_set_head(lp, new);
1702 if (err)
1703 break;
1704 goto no_data;
1705 }
1706
1707 pkt_len = p->env & LDC_LEN;
1708
1709 /* Every initial packet starts with the START bit set.
1710 *
1711 * Singleton packets will have both START+STOP set.
1712 *
1713 * Fragments will have START set in the first frame, STOP
1714 * set in the last frame, and neither bit set in middle
1715 * frames of the packet.
1716 *
1717 * Therefore if we are at the beginning of a packet and
1718 * we don't see START, or we are in the middle of a fragmented
1719 * packet and do see START, we are unsynchronized and should
1720 * flush the RX queue.
1721 */
1722 if ((first_frag == NULL && !(p->env & LDC_START)) ||
1723 (first_frag != NULL && (p->env & LDC_START))) {
1724 if (!first_frag)
1725 new = rx_advance(lp, new);
1726
1727 err = rx_set_head(lp, new);
1728 if (err)
1729 break;
1730
1731 if (!first_frag)
1732 goto no_data;
1733 }
1734 if (!first_frag)
1735 first_frag = p;
1736
1737 if (pkt_len > size - copied) {
1738 /* User didn't give us a big enough buffer,
1739 * what to do? This is a pretty serious error.
1740 *
1741 * Since we haven't updated the RX ring head to
1742 * consume any of the packets, signal the error
1743 * to the user and just leave the RX ring alone.
1744 *
1745 * This seems the best behavior because this allows
1746 * a user of the LDC layer to start with a small
1747 * RX buffer for ldc_read() calls and use -EMSGSIZE
1748 * as a cue to enlarge it's read buffer.
1749 */
1750 err = -EMSGSIZE;
1751 break;
1752 }
1753
1754 /* Ok, we are gonna eat this one. */
1755 new = rx_advance(lp, new);
1756
1757 memcpy(buf,
1758 (lp->cfg.mode == LDC_MODE_UNRELIABLE ?
1759 p->u.u_data : p->u.r.r_data), pkt_len);
1760 buf += pkt_len;
1761 copied += pkt_len;
1762
1763 if (p->env & LDC_STOP)
1764 break;
1765
1766 no_data:
1767 if (new == lp->rx_tail) {
1768 err = rx_data_wait(lp, new);
1769 if (err)
1770 break;
1771 }
1772 }
1773
1774 if (!err)
1775 err = rx_set_head(lp, new);
1776
1777 if (err && first_frag)
1778 lp->rcv_nxt = first_frag->seqid - 1;
1779
1780 if (!err) {
1781 err = copied;
1782 if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE)
1783 send_data_ack(lp);
1784 }
1785
1786 return err;
1787 }
1788
1789 static const struct ldc_mode_ops nonraw_ops = {
1790 .write = write_nonraw,
1791 .read = read_nonraw,
1792 };
1793
1794 static int write_stream(struct ldc_channel *lp, const void *buf,
1795 unsigned int size)
1796 {
1797 if (size > lp->cfg.mtu)
1798 size = lp->cfg.mtu;
1799 return write_nonraw(lp, buf, size);
1800 }
1801
1802 static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size)
1803 {
1804 if (!lp->mssbuf_len) {
1805 int err = read_nonraw(lp, lp->mssbuf, lp->cfg.mtu);
1806 if (err < 0)
1807 return err;
1808
1809 lp->mssbuf_len = err;
1810 lp->mssbuf_off = 0;
1811 }
1812
1813 if (size > lp->mssbuf_len)
1814 size = lp->mssbuf_len;
1815 memcpy(buf, lp->mssbuf + lp->mssbuf_off, size);
1816
1817 lp->mssbuf_off += size;
1818 lp->mssbuf_len -= size;
1819
1820 return size;
1821 }
1822
1823 static const struct ldc_mode_ops stream_ops = {
1824 .write = write_stream,
1825 .read = read_stream,
1826 };
1827
1828 int ldc_write(struct ldc_channel *lp, const void *buf, unsigned int size)
1829 {
1830 unsigned long flags;
1831 int err;
1832
1833 if (!buf)
1834 return -EINVAL;
1835
1836 if (!size)
1837 return 0;
1838
1839 spin_lock_irqsave(&lp->lock, flags);
1840
1841 if (lp->hs_state != LDC_HS_COMPLETE)
1842 err = -ENOTCONN;
1843 else
1844 err = lp->mops->write(lp, buf, size);
1845
1846 spin_unlock_irqrestore(&lp->lock, flags);
1847
1848 return err;
1849 }
1850 EXPORT_SYMBOL(ldc_write);
1851
1852 int ldc_read(struct ldc_channel *lp, void *buf, unsigned int size)
1853 {
1854 unsigned long flags;
1855 int err;
1856
1857 if (!buf)
1858 return -EINVAL;
1859
1860 if (!size)
1861 return 0;
1862
1863 spin_lock_irqsave(&lp->lock, flags);
1864
1865 if (lp->hs_state != LDC_HS_COMPLETE)
1866 err = -ENOTCONN;
1867 else
1868 err = lp->mops->read(lp, buf, size);
1869
1870 spin_unlock_irqrestore(&lp->lock, flags);
1871
1872 return err;
1873 }
1874 EXPORT_SYMBOL(ldc_read);
1875
1876 static long arena_alloc(struct ldc_iommu *iommu, unsigned long npages)
1877 {
1878 struct iommu_arena *arena = &iommu->arena;
1879 unsigned long n, i, start, end, limit;
1880 int pass;
1881
1882 limit = arena->limit;
1883 start = arena->hint;
1884 pass = 0;
1885
1886 again:
1887 n = find_next_zero_bit(arena->map, limit, start);
1888 end = n + npages;
1889 if (unlikely(end >= limit)) {
1890 if (likely(pass < 1)) {
1891 limit = start;
1892 start = 0;
1893 pass++;
1894 goto again;
1895 } else {
1896 /* Scanned the whole thing, give up. */
1897 return -1;
1898 }
1899 }
1900
1901 for (i = n; i < end; i++) {
1902 if (test_bit(i, arena->map)) {
1903 start = i + 1;
1904 goto again;
1905 }
1906 }
1907
1908 for (i = n; i < end; i++)
1909 __set_bit(i, arena->map);
1910
1911 arena->hint = end;
1912
1913 return n;
1914 }
1915
1916 #define COOKIE_PGSZ_CODE 0xf000000000000000ULL
1917 #define COOKIE_PGSZ_CODE_SHIFT 60ULL
1918
1919 static u64 pagesize_code(void)
1920 {
1921 switch (PAGE_SIZE) {
1922 default:
1923 case (8ULL * 1024ULL):
1924 return 0;
1925 case (64ULL * 1024ULL):
1926 return 1;
1927 case (512ULL * 1024ULL):
1928 return 2;
1929 case (4ULL * 1024ULL * 1024ULL):
1930 return 3;
1931 case (32ULL * 1024ULL * 1024ULL):
1932 return 4;
1933 case (256ULL * 1024ULL * 1024ULL):
1934 return 5;
1935 }
1936 }
1937
1938 static u64 make_cookie(u64 index, u64 pgsz_code, u64 page_offset)
1939 {
1940 return ((pgsz_code << COOKIE_PGSZ_CODE_SHIFT) |
1941 (index << PAGE_SHIFT) |
1942 page_offset);
1943 }
1944
1945 static u64 cookie_to_index(u64 cookie, unsigned long *shift)
1946 {
1947 u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT;
1948
1949 cookie &= ~COOKIE_PGSZ_CODE;
1950
1951 *shift = szcode * 3;
1952
1953 return (cookie >> (13ULL + (szcode * 3ULL)));
1954 }
1955
1956 static struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu,
1957 unsigned long npages)
1958 {
1959 long entry;
1960
1961 entry = arena_alloc(iommu, npages);
1962 if (unlikely(entry < 0))
1963 return NULL;
1964
1965 return iommu->page_table + entry;
1966 }
1967
1968 static u64 perm_to_mte(unsigned int map_perm)
1969 {
1970 u64 mte_base;
1971
1972 mte_base = pagesize_code();
1973
1974 if (map_perm & LDC_MAP_SHADOW) {
1975 if (map_perm & LDC_MAP_R)
1976 mte_base |= LDC_MTE_COPY_R;
1977 if (map_perm & LDC_MAP_W)
1978 mte_base |= LDC_MTE_COPY_W;
1979 }
1980 if (map_perm & LDC_MAP_DIRECT) {
1981 if (map_perm & LDC_MAP_R)
1982 mte_base |= LDC_MTE_READ;
1983 if (map_perm & LDC_MAP_W)
1984 mte_base |= LDC_MTE_WRITE;
1985 if (map_perm & LDC_MAP_X)
1986 mte_base |= LDC_MTE_EXEC;
1987 }
1988 if (map_perm & LDC_MAP_IO) {
1989 if (map_perm & LDC_MAP_R)
1990 mte_base |= LDC_MTE_IOMMU_R;
1991 if (map_perm & LDC_MAP_W)
1992 mte_base |= LDC_MTE_IOMMU_W;
1993 }
1994
1995 return mte_base;
1996 }
1997
1998 static int pages_in_region(unsigned long base, long len)
1999 {
2000 int count = 0;
2001
2002 do {
2003 unsigned long new = (base + PAGE_SIZE) & PAGE_MASK;
2004
2005 len -= (new - base);
2006 base = new;
2007 count++;
2008 } while (len > 0);
2009
2010 return count;
2011 }
2012
2013 struct cookie_state {
2014 struct ldc_mtable_entry *page_table;
2015 struct ldc_trans_cookie *cookies;
2016 u64 mte_base;
2017 u64 prev_cookie;
2018 u32 pte_idx;
2019 u32 nc;
2020 };
2021
2022 static void fill_cookies(struct cookie_state *sp, unsigned long pa,
2023 unsigned long off, unsigned long len)
2024 {
2025 do {
2026 unsigned long tlen, new = pa + PAGE_SIZE;
2027 u64 this_cookie;
2028
2029 sp->page_table[sp->pte_idx].mte = sp->mte_base | pa;
2030
2031 tlen = PAGE_SIZE;
2032 if (off)
2033 tlen = PAGE_SIZE - off;
2034 if (tlen > len)
2035 tlen = len;
2036
2037 this_cookie = make_cookie(sp->pte_idx,
2038 pagesize_code(), off);
2039
2040 off = 0;
2041
2042 if (this_cookie == sp->prev_cookie) {
2043 sp->cookies[sp->nc - 1].cookie_size += tlen;
2044 } else {
2045 sp->cookies[sp->nc].cookie_addr = this_cookie;
2046 sp->cookies[sp->nc].cookie_size = tlen;
2047 sp->nc++;
2048 }
2049 sp->prev_cookie = this_cookie + tlen;
2050
2051 sp->pte_idx++;
2052
2053 len -= tlen;
2054 pa = new;
2055 } while (len > 0);
2056 }
2057
2058 static int sg_count_one(struct scatterlist *sg)
2059 {
2060 unsigned long base = page_to_pfn(sg_page(sg)) << PAGE_SHIFT;
2061 long len = sg->length;
2062
2063 if ((sg->offset | len) & (8UL - 1))
2064 return -EFAULT;
2065
2066 return pages_in_region(base + sg->offset, len);
2067 }
2068
2069 static int sg_count_pages(struct scatterlist *sg, int num_sg)
2070 {
2071 int count;
2072 int i;
2073
2074 count = 0;
2075 for (i = 0; i < num_sg; i++) {
2076 int err = sg_count_one(sg + i);
2077 if (err < 0)
2078 return err;
2079 count += err;
2080 }
2081
2082 return count;
2083 }
2084
2085 int ldc_map_sg(struct ldc_channel *lp,
2086 struct scatterlist *sg, int num_sg,
2087 struct ldc_trans_cookie *cookies, int ncookies,
2088 unsigned int map_perm)
2089 {
2090 unsigned long i, npages, flags;
2091 struct ldc_mtable_entry *base;
2092 struct cookie_state state;
2093 struct ldc_iommu *iommu;
2094 int err;
2095
2096 if (map_perm & ~LDC_MAP_ALL)
2097 return -EINVAL;
2098
2099 err = sg_count_pages(sg, num_sg);
2100 if (err < 0)
2101 return err;
2102
2103 npages = err;
2104 if (err > ncookies)
2105 return -EMSGSIZE;
2106
2107 iommu = &lp->iommu;
2108
2109 spin_lock_irqsave(&iommu->lock, flags);
2110 base = alloc_npages(iommu, npages);
2111 spin_unlock_irqrestore(&iommu->lock, flags);
2112
2113 if (!base)
2114 return -ENOMEM;
2115
2116 state.page_table = iommu->page_table;
2117 state.cookies = cookies;
2118 state.mte_base = perm_to_mte(map_perm);
2119 state.prev_cookie = ~(u64)0;
2120 state.pte_idx = (base - iommu->page_table);
2121 state.nc = 0;
2122
2123 for (i = 0; i < num_sg; i++)
2124 fill_cookies(&state, page_to_pfn(sg_page(&sg[i])) << PAGE_SHIFT,
2125 sg[i].offset, sg[i].length);
2126
2127 return state.nc;
2128 }
2129 EXPORT_SYMBOL(ldc_map_sg);
2130
2131 int ldc_map_single(struct ldc_channel *lp,
2132 void *buf, unsigned int len,
2133 struct ldc_trans_cookie *cookies, int ncookies,
2134 unsigned int map_perm)
2135 {
2136 unsigned long npages, pa, flags;
2137 struct ldc_mtable_entry *base;
2138 struct cookie_state state;
2139 struct ldc_iommu *iommu;
2140
2141 if ((map_perm & ~LDC_MAP_ALL) || (ncookies < 1))
2142 return -EINVAL;
2143
2144 pa = __pa(buf);
2145 if ((pa | len) & (8UL - 1))
2146 return -EFAULT;
2147
2148 npages = pages_in_region(pa, len);
2149
2150 iommu = &lp->iommu;
2151
2152 spin_lock_irqsave(&iommu->lock, flags);
2153 base = alloc_npages(iommu, npages);
2154 spin_unlock_irqrestore(&iommu->lock, flags);
2155
2156 if (!base)
2157 return -ENOMEM;
2158
2159 state.page_table = iommu->page_table;
2160 state.cookies = cookies;
2161 state.mte_base = perm_to_mte(map_perm);
2162 state.prev_cookie = ~(u64)0;
2163 state.pte_idx = (base - iommu->page_table);
2164 state.nc = 0;
2165 fill_cookies(&state, (pa & PAGE_MASK), (pa & ~PAGE_MASK), len);
2166 BUG_ON(state.nc != 1);
2167
2168 return state.nc;
2169 }
2170 EXPORT_SYMBOL(ldc_map_single);
2171
2172 static void free_npages(unsigned long id, struct ldc_iommu *iommu,
2173 u64 cookie, u64 size)
2174 {
2175 struct iommu_arena *arena = &iommu->arena;
2176 unsigned long i, shift, index, npages;
2177 struct ldc_mtable_entry *base;
2178
2179 npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT;
2180 index = cookie_to_index(cookie, &shift);
2181 base = iommu->page_table + index;
2182
2183 BUG_ON(index > arena->limit ||
2184 (index + npages) > arena->limit);
2185
2186 for (i = 0; i < npages; i++) {
2187 if (base->cookie)
2188 sun4v_ldc_revoke(id, cookie + (i << shift),
2189 base->cookie);
2190 base->mte = 0;
2191 __clear_bit(index + i, arena->map);
2192 }
2193 }
2194
2195 void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies,
2196 int ncookies)
2197 {
2198 struct ldc_iommu *iommu = &lp->iommu;
2199 unsigned long flags;
2200 int i;
2201
2202 spin_lock_irqsave(&iommu->lock, flags);
2203 for (i = 0; i < ncookies; i++) {
2204 u64 addr = cookies[i].cookie_addr;
2205 u64 size = cookies[i].cookie_size;
2206
2207 free_npages(lp->id, iommu, addr, size);
2208 }
2209 spin_unlock_irqrestore(&iommu->lock, flags);
2210 }
2211 EXPORT_SYMBOL(ldc_unmap);
2212
2213 int ldc_copy(struct ldc_channel *lp, int copy_dir,
2214 void *buf, unsigned int len, unsigned long offset,
2215 struct ldc_trans_cookie *cookies, int ncookies)
2216 {
2217 unsigned int orig_len;
2218 unsigned long ra;
2219 int i;
2220
2221 if (copy_dir != LDC_COPY_IN && copy_dir != LDC_COPY_OUT) {
2222 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Bad copy_dir[%d]\n",
2223 lp->id, copy_dir);
2224 return -EINVAL;
2225 }
2226
2227 ra = __pa(buf);
2228 if ((ra | len | offset) & (8UL - 1)) {
2229 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Unaligned buffer "
2230 "ra[%lx] len[%x] offset[%lx]\n",
2231 lp->id, ra, len, offset);
2232 return -EFAULT;
2233 }
2234
2235 if (lp->hs_state != LDC_HS_COMPLETE ||
2236 (lp->flags & LDC_FLAG_RESET)) {
2237 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Link down hs_state[%x] "
2238 "flags[%x]\n", lp->id, lp->hs_state, lp->flags);
2239 return -ECONNRESET;
2240 }
2241
2242 orig_len = len;
2243 for (i = 0; i < ncookies; i++) {
2244 unsigned long cookie_raddr = cookies[i].cookie_addr;
2245 unsigned long this_len = cookies[i].cookie_size;
2246 unsigned long actual_len;
2247
2248 if (unlikely(offset)) {
2249 unsigned long this_off = offset;
2250
2251 if (this_off > this_len)
2252 this_off = this_len;
2253
2254 offset -= this_off;
2255 this_len -= this_off;
2256 if (!this_len)
2257 continue;
2258 cookie_raddr += this_off;
2259 }
2260
2261 if (this_len > len)
2262 this_len = len;
2263
2264 while (1) {
2265 unsigned long hv_err;
2266
2267 hv_err = sun4v_ldc_copy(lp->id, copy_dir,
2268 cookie_raddr, ra,
2269 this_len, &actual_len);
2270 if (unlikely(hv_err)) {
2271 printk(KERN_ERR PFX "ldc_copy: ID[%lu] "
2272 "HV error %lu\n",
2273 lp->id, hv_err);
2274 if (lp->hs_state != LDC_HS_COMPLETE ||
2275 (lp->flags & LDC_FLAG_RESET))
2276 return -ECONNRESET;
2277 else
2278 return -EFAULT;
2279 }
2280
2281 cookie_raddr += actual_len;
2282 ra += actual_len;
2283 len -= actual_len;
2284 if (actual_len == this_len)
2285 break;
2286
2287 this_len -= actual_len;
2288 }
2289
2290 if (!len)
2291 break;
2292 }
2293
2294 /* It is caller policy what to do about short copies.
2295 * For example, a networking driver can declare the
2296 * packet a runt and drop it.
2297 */
2298
2299 return orig_len - len;
2300 }
2301 EXPORT_SYMBOL(ldc_copy);
2302
2303 void *ldc_alloc_exp_dring(struct ldc_channel *lp, unsigned int len,
2304 struct ldc_trans_cookie *cookies, int *ncookies,
2305 unsigned int map_perm)
2306 {
2307 void *buf;
2308 int err;
2309
2310 if (len & (8UL - 1))
2311 return ERR_PTR(-EINVAL);
2312
2313 buf = kzalloc(len, GFP_KERNEL);
2314 if (!buf)
2315 return ERR_PTR(-ENOMEM);
2316
2317 err = ldc_map_single(lp, buf, len, cookies, *ncookies, map_perm);
2318 if (err < 0) {
2319 kfree(buf);
2320 return ERR_PTR(err);
2321 }
2322 *ncookies = err;
2323
2324 return buf;
2325 }
2326 EXPORT_SYMBOL(ldc_alloc_exp_dring);
2327
2328 void ldc_free_exp_dring(struct ldc_channel *lp, void *buf, unsigned int len,
2329 struct ldc_trans_cookie *cookies, int ncookies)
2330 {
2331 ldc_unmap(lp, cookies, ncookies);
2332 kfree(buf);
2333 }
2334 EXPORT_SYMBOL(ldc_free_exp_dring);
2335
2336 static int __init ldc_init(void)
2337 {
2338 unsigned long major, minor;
2339 struct mdesc_handle *hp;
2340 const u64 *v;
2341 int err;
2342 u64 mp;
2343
2344 hp = mdesc_grab();
2345 if (!hp)
2346 return -ENODEV;
2347
2348 mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
2349 err = -ENODEV;
2350 if (mp == MDESC_NODE_NULL)
2351 goto out;
2352
2353 v = mdesc_get_property(hp, mp, "domaining-enabled", NULL);
2354 if (!v)
2355 goto out;
2356
2357 major = 1;
2358 minor = 0;
2359 if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) {
2360 printk(KERN_INFO PFX "Could not register LDOM hvapi.\n");
2361 goto out;
2362 }
2363
2364 printk(KERN_INFO "%s", version);
2365
2366 if (!*v) {
2367 printk(KERN_INFO PFX "Domaining disabled.\n");
2368 goto out;
2369 }
2370 ldom_domaining_enabled = 1;
2371 err = 0;
2372
2373 out:
2374 mdesc_release(hp);
2375 return err;
2376 }
2377
2378 core_initcall(ldc_init);
Linux kernel - Deliverables
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