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