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 struct ldc_packet *p; 629 unsigned long new_tail; 630 631 if (vp->major == 0 && vp->minor == 0) 632 return ldc_abort(lp); 633 634 vap = find_by_major(vp->major); 635 if (!vap) 636 return ldc_abort(lp); 637 638 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS, 639 vap, sizeof(*vap), 640 &new_tail); 641 if (!p) 642 return ldc_abort(lp); 643 644 return send_tx_packet(lp, p, new_tail); 645 } 646 647 static int process_version(struct ldc_channel *lp, 648 struct ldc_packet *p) 649 { 650 struct ldc_version *vp; 651 652 vp = (struct ldc_version *) p->u.u_data; 653 654 switch (p->stype) { 655 case LDC_INFO: 656 return process_ver_info(lp, vp); 657 658 case LDC_ACK: 659 return process_ver_ack(lp, vp); 660 661 case LDC_NACK: 662 return process_ver_nack(lp, vp); 663 664 default: 665 return ldc_abort(lp); 666 } 667 } 668 669 static int process_rts(struct ldc_channel *lp, 670 struct ldc_packet *p) 671 { 672 ldcdbg(HS, "GOT RTS stype[%x] seqid[%x] env[%x]\n", 673 p->stype, p->seqid, p->env); 674 675 if (p->stype != LDC_INFO || 676 lp->hs_state != LDC_HS_GOTVERS || 677 p->env != lp->cfg.mode) 678 return ldc_abort(lp); 679 680 lp->snd_nxt = p->seqid; 681 lp->rcv_nxt = p->seqid; 682 lp->hs_state = LDC_HS_SENTRTR; 683 if (send_rtr(lp)) 684 return ldc_abort(lp); 685 686 return 0; 687 } 688 689 static int process_rtr(struct ldc_channel *lp, 690 struct ldc_packet *p) 691 { 692 ldcdbg(HS, "GOT RTR stype[%x] seqid[%x] env[%x]\n", 693 p->stype, p->seqid, p->env); 694 695 if (p->stype != LDC_INFO || 696 p->env != lp->cfg.mode) 697 return ldc_abort(lp); 698 699 lp->snd_nxt = p->seqid; 700 lp->hs_state = LDC_HS_COMPLETE; 701 ldc_set_state(lp, LDC_STATE_CONNECTED); 702 send_rdx(lp); 703 704 return LDC_EVENT_UP; 705 } 706 707 static int rx_seq_ok(struct ldc_channel *lp, u32 seqid) 708 { 709 return lp->rcv_nxt + 1 == seqid; 710 } 711 712 static int process_rdx(struct ldc_channel *lp, 713 struct ldc_packet *p) 714 { 715 ldcdbg(HS, "GOT RDX stype[%x] seqid[%x] env[%x] ackid[%x]\n", 716 p->stype, p->seqid, p->env, p->u.r.ackid); 717 718 if (p->stype != LDC_INFO || 719 !(rx_seq_ok(lp, p->seqid))) 720 return ldc_abort(lp); 721 722 lp->rcv_nxt = p->seqid; 723 724 lp->hs_state = LDC_HS_COMPLETE; 725 ldc_set_state(lp, LDC_STATE_CONNECTED); 726 727 return LDC_EVENT_UP; 728 } 729 730 static int process_control_frame(struct ldc_channel *lp, 731 struct ldc_packet *p) 732 { 733 switch (p->ctrl) { 734 case LDC_VERS: 735 return process_version(lp, p); 736 737 case LDC_RTS: 738 return process_rts(lp, p); 739 740 case LDC_RTR: 741 return process_rtr(lp, p); 742 743 case LDC_RDX: 744 return process_rdx(lp, p); 745 746 default: 747 return ldc_abort(lp); 748 } 749 } 750 751 static int process_error_frame(struct ldc_channel *lp, 752 struct ldc_packet *p) 753 { 754 return ldc_abort(lp); 755 } 756 757 static int process_data_ack(struct ldc_channel *lp, 758 struct ldc_packet *ack) 759 { 760 unsigned long head = lp->tx_acked; 761 u32 ackid = ack->u.r.ackid; 762 763 while (1) { 764 struct ldc_packet *p = lp->tx_base + (head / LDC_PACKET_SIZE); 765 766 head = tx_advance(lp, head); 767 768 if (p->seqid == ackid) { 769 lp->tx_acked = head; 770 return 0; 771 } 772 if (head == lp->tx_tail) 773 return ldc_abort(lp); 774 } 775 776 return 0; 777 } 778 779 static void send_events(struct ldc_channel *lp, unsigned int event_mask) 780 { 781 if (event_mask & LDC_EVENT_RESET) 782 lp->cfg.event(lp->event_arg, LDC_EVENT_RESET); 783 if (event_mask & LDC_EVENT_UP) 784 lp->cfg.event(lp->event_arg, LDC_EVENT_UP); 785 if (event_mask & LDC_EVENT_DATA_READY) 786 lp->cfg.event(lp->event_arg, LDC_EVENT_DATA_READY); 787 } 788 789 static irqreturn_t ldc_rx(int irq, void *dev_id) 790 { 791 struct ldc_channel *lp = dev_id; 792 unsigned long orig_state, hv_err, flags; 793 unsigned int event_mask; 794 795 spin_lock_irqsave(&lp->lock, flags); 796 797 orig_state = lp->chan_state; 798 hv_err = sun4v_ldc_rx_get_state(lp->id, 799 &lp->rx_head, 800 &lp->rx_tail, 801 &lp->chan_state); 802 803 ldcdbg(RX, "RX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n", 804 orig_state, lp->chan_state, lp->rx_head, lp->rx_tail); 805 806 event_mask = 0; 807 808 if (lp->cfg.mode == LDC_MODE_RAW && 809 lp->chan_state == LDC_CHANNEL_UP) { 810 lp->hs_state = LDC_HS_COMPLETE; 811 ldc_set_state(lp, LDC_STATE_CONNECTED); 812 813 event_mask |= LDC_EVENT_UP; 814 815 orig_state = lp->chan_state; 816 } 817 818 /* If we are in reset state, flush the RX queue and ignore 819 * everything. 820 */ 821 if (lp->flags & LDC_FLAG_RESET) { 822 (void) __set_rx_head(lp, lp->rx_tail); 823 goto out; 824 } 825 826 /* Once we finish the handshake, we let the ldc_read() 827 * paths do all of the control frame and state management. 828 * Just trigger the callback. 829 */ 830 if (lp->hs_state == LDC_HS_COMPLETE) { 831 handshake_complete: 832 if (lp->chan_state != orig_state) { 833 unsigned int event = LDC_EVENT_RESET; 834 835 if (lp->chan_state == LDC_CHANNEL_UP) 836 event = LDC_EVENT_UP; 837 838 event_mask |= event; 839 } 840 if (lp->rx_head != lp->rx_tail) 841 event_mask |= LDC_EVENT_DATA_READY; 842 843 goto out; 844 } 845 846 if (lp->chan_state != orig_state) 847 goto out; 848 849 while (lp->rx_head != lp->rx_tail) { 850 struct ldc_packet *p; 851 unsigned long new; 852 int err; 853 854 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE); 855 856 switch (p->type) { 857 case LDC_CTRL: 858 err = process_control_frame(lp, p); 859 if (err > 0) 860 event_mask |= err; 861 break; 862 863 case LDC_DATA: 864 event_mask |= LDC_EVENT_DATA_READY; 865 err = 0; 866 break; 867 868 case LDC_ERR: 869 err = process_error_frame(lp, p); 870 break; 871 872 default: 873 err = ldc_abort(lp); 874 break; 875 } 876 877 if (err < 0) 878 break; 879 880 new = lp->rx_head; 881 new += LDC_PACKET_SIZE; 882 if (new == (lp->rx_num_entries * LDC_PACKET_SIZE)) 883 new = 0; 884 lp->rx_head = new; 885 886 err = __set_rx_head(lp, new); 887 if (err < 0) { 888 (void) ldc_abort(lp); 889 break; 890 } 891 if (lp->hs_state == LDC_HS_COMPLETE) 892 goto handshake_complete; 893 } 894 895 out: 896 spin_unlock_irqrestore(&lp->lock, flags); 897 898 send_events(lp, event_mask); 899 900 return IRQ_HANDLED; 901 } 902 903 static irqreturn_t ldc_tx(int irq, void *dev_id) 904 { 905 struct ldc_channel *lp = dev_id; 906 unsigned long flags, hv_err, orig_state; 907 unsigned int event_mask = 0; 908 909 spin_lock_irqsave(&lp->lock, flags); 910 911 orig_state = lp->chan_state; 912 hv_err = sun4v_ldc_tx_get_state(lp->id, 913 &lp->tx_head, 914 &lp->tx_tail, 915 &lp->chan_state); 916 917 ldcdbg(TX, " TX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n", 918 orig_state, lp->chan_state, lp->tx_head, lp->tx_tail); 919 920 if (lp->cfg.mode == LDC_MODE_RAW && 921 lp->chan_state == LDC_CHANNEL_UP) { 922 lp->hs_state = LDC_HS_COMPLETE; 923 ldc_set_state(lp, LDC_STATE_CONNECTED); 924 925 event_mask |= LDC_EVENT_UP; 926 } 927 928 spin_unlock_irqrestore(&lp->lock, flags); 929 930 send_events(lp, event_mask); 931 932 return IRQ_HANDLED; 933 } 934 935 /* XXX ldc_alloc() and ldc_free() needs to run under a mutex so 936 * XXX that addition and removal from the ldc_channel_list has 937 * XXX atomicity, otherwise the __ldc_channel_exists() check is 938 * XXX totally pointless as another thread can slip into ldc_alloc() 939 * XXX and add a channel with the same ID. There also needs to be 940 * XXX a spinlock for ldc_channel_list. 941 */ 942 static HLIST_HEAD(ldc_channel_list); 943 944 static int __ldc_channel_exists(unsigned long id) 945 { 946 struct ldc_channel *lp; 947 struct hlist_node *n; 948 949 hlist_for_each_entry(lp, n, &ldc_channel_list, list) { 950 if (lp->id == id) 951 return 1; 952 } 953 return 0; 954 } 955 956 static int alloc_queue(const char *name, unsigned long num_entries, 957 struct ldc_packet **base, unsigned long *ra) 958 { 959 unsigned long size, order; 960 void *q; 961 962 size = num_entries * LDC_PACKET_SIZE; 963 order = get_order(size); 964 965 q = (void *) __get_free_pages(GFP_KERNEL, order); 966 if (!q) { 967 printk(KERN_ERR PFX "Alloc of %s queue failed with " 968 "size=%lu order=%lu\n", name, size, order); 969 return -ENOMEM; 970 } 971 972 memset(q, 0, PAGE_SIZE << order); 973 974 *base = q; 975 *ra = __pa(q); 976 977 return 0; 978 } 979 980 static void free_queue(unsigned long num_entries, struct ldc_packet *q) 981 { 982 unsigned long size, order; 983 984 if (!q) 985 return; 986 987 size = num_entries * LDC_PACKET_SIZE; 988 order = get_order(size); 989 990 free_pages((unsigned long)q, order); 991 } 992 993 /* XXX Make this configurable... XXX */ 994 #define LDC_IOTABLE_SIZE (8 * 1024) 995 996 static int ldc_iommu_init(struct ldc_channel *lp) 997 { 998 unsigned long sz, num_tsb_entries, tsbsize, order; 999 struct ldc_iommu *iommu = &lp->iommu; 1000 struct ldc_mtable_entry *table; 1001 unsigned long hv_err; 1002 int err; 1003 1004 num_tsb_entries = LDC_IOTABLE_SIZE; 1005 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry); 1006 1007 spin_lock_init(&iommu->lock); 1008 1009 sz = num_tsb_entries / 8; 1010 sz = (sz + 7UL) & ~7UL; 1011 iommu->arena.map = kzalloc(sz, GFP_KERNEL); 1012 if (!iommu->arena.map) { 1013 printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz); 1014 return -ENOMEM; 1015 } 1016 1017 iommu->arena.limit = num_tsb_entries; 1018 1019 order = get_order(tsbsize); 1020 1021 table = (struct ldc_mtable_entry *) 1022 __get_free_pages(GFP_KERNEL, order); 1023 err = -ENOMEM; 1024 if (!table) { 1025 printk(KERN_ERR PFX "Alloc of MTE table failed, " 1026 "size=%lu order=%lu\n", tsbsize, order); 1027 goto out_free_map; 1028 } 1029 1030 memset(table, 0, PAGE_SIZE << order); 1031 1032 iommu->page_table = table; 1033 1034 hv_err = sun4v_ldc_set_map_table(lp->id, __pa(table), 1035 num_tsb_entries); 1036 err = -EINVAL; 1037 if (hv_err) 1038 goto out_free_table; 1039 1040 return 0; 1041 1042 out_free_table: 1043 free_pages((unsigned long) table, order); 1044 iommu->page_table = NULL; 1045 1046 out_free_map: 1047 kfree(iommu->arena.map); 1048 iommu->arena.map = NULL; 1049 1050 return err; 1051 } 1052 1053 static void ldc_iommu_release(struct ldc_channel *lp) 1054 { 1055 struct ldc_iommu *iommu = &lp->iommu; 1056 unsigned long num_tsb_entries, tsbsize, order; 1057 1058 (void) sun4v_ldc_set_map_table(lp->id, 0, 0); 1059 1060 num_tsb_entries = iommu->arena.limit; 1061 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry); 1062 order = get_order(tsbsize); 1063 1064 free_pages((unsigned long) iommu->page_table, order); 1065 iommu->page_table = NULL; 1066 1067 kfree(iommu->arena.map); 1068 iommu->arena.map = NULL; 1069 } 1070 1071 struct ldc_channel *ldc_alloc(unsigned long id, 1072 const struct ldc_channel_config *cfgp, 1073 void *event_arg) 1074 { 1075 struct ldc_channel *lp; 1076 const struct ldc_mode_ops *mops; 1077 unsigned long dummy1, dummy2, hv_err; 1078 u8 mss, *mssbuf; 1079 int err; 1080 1081 err = -ENODEV; 1082 if (!ldom_domaining_enabled) 1083 goto out_err; 1084 1085 err = -EINVAL; 1086 if (!cfgp) 1087 goto out_err; 1088 1089 switch (cfgp->mode) { 1090 case LDC_MODE_RAW: 1091 mops = &raw_ops; 1092 mss = LDC_PACKET_SIZE; 1093 break; 1094 1095 case LDC_MODE_UNRELIABLE: 1096 mops = &nonraw_ops; 1097 mss = LDC_PACKET_SIZE - 8; 1098 break; 1099 1100 case LDC_MODE_STREAM: 1101 mops = &stream_ops; 1102 mss = LDC_PACKET_SIZE - 8 - 8; 1103 break; 1104 1105 default: 1106 goto out_err; 1107 } 1108 1109 if (!cfgp->event || !event_arg || !cfgp->rx_irq || !cfgp->tx_irq) 1110 goto out_err; 1111 1112 hv_err = sun4v_ldc_tx_qinfo(id, &dummy1, &dummy2); 1113 err = -ENODEV; 1114 if (hv_err == HV_ECHANNEL) 1115 goto out_err; 1116 1117 err = -EEXIST; 1118 if (__ldc_channel_exists(id)) 1119 goto out_err; 1120 1121 mssbuf = NULL; 1122 1123 lp = kzalloc(sizeof(*lp), GFP_KERNEL); 1124 err = -ENOMEM; 1125 if (!lp) 1126 goto out_err; 1127 1128 spin_lock_init(&lp->lock); 1129 1130 lp->id = id; 1131 1132 err = ldc_iommu_init(lp); 1133 if (err) 1134 goto out_free_ldc; 1135 1136 lp->mops = mops; 1137 lp->mss = mss; 1138 1139 lp->cfg = *cfgp; 1140 if (!lp->cfg.mtu) 1141 lp->cfg.mtu = LDC_DEFAULT_MTU; 1142 1143 if (lp->cfg.mode == LDC_MODE_STREAM) { 1144 mssbuf = kzalloc(lp->cfg.mtu, GFP_KERNEL); 1145 if (!mssbuf) { 1146 err = -ENOMEM; 1147 goto out_free_iommu; 1148 } 1149 lp->mssbuf = mssbuf; 1150 } 1151 1152 lp->event_arg = event_arg; 1153 1154 /* XXX allow setting via ldc_channel_config to override defaults 1155 * XXX or use some formula based upon mtu 1156 */ 1157 lp->tx_num_entries = LDC_DEFAULT_NUM_ENTRIES; 1158 lp->rx_num_entries = LDC_DEFAULT_NUM_ENTRIES; 1159 1160 err = alloc_queue("TX", lp->tx_num_entries, 1161 &lp->tx_base, &lp->tx_ra); 1162 if (err) 1163 goto out_free_mssbuf; 1164 1165 err = alloc_queue("RX", lp->rx_num_entries, 1166 &lp->rx_base, &lp->rx_ra); 1167 if (err) 1168 goto out_free_txq; 1169 1170 lp->flags |= LDC_FLAG_ALLOCED_QUEUES; 1171 1172 lp->hs_state = LDC_HS_CLOSED; 1173 ldc_set_state(lp, LDC_STATE_INIT); 1174 1175 INIT_HLIST_NODE(&lp->list); 1176 hlist_add_head(&lp->list, &ldc_channel_list); 1177 1178 INIT_HLIST_HEAD(&lp->mh_list); 1179 1180 return lp; 1181 1182 out_free_txq: 1183 free_queue(lp->tx_num_entries, lp->tx_base); 1184 1185 out_free_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 kfree(lp->mssbuf); 1220 1221 ldc_iommu_release(lp); 1222 1223 kfree(lp); 1224 } 1225 EXPORT_SYMBOL(ldc_free); 1226 1227 /* Bind the channel. This registers the LDC queues with 1228 * the hypervisor and puts the channel into a pseudo-listening 1229 * state. This does not initiate a handshake, ldc_connect() does 1230 * that. 1231 */ 1232 int ldc_bind(struct ldc_channel *lp, const char *name) 1233 { 1234 unsigned long hv_err, flags; 1235 int err = -EINVAL; 1236 1237 if (!name || 1238 (lp->state != LDC_STATE_INIT)) 1239 return -EINVAL; 1240 1241 snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name); 1242 snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name); 1243 1244 err = request_irq(lp->cfg.rx_irq, ldc_rx, 1245 IRQF_SAMPLE_RANDOM | IRQF_DISABLED | IRQF_SHARED, 1246 lp->rx_irq_name, lp); 1247 if (err) 1248 return err; 1249 1250 err = request_irq(lp->cfg.tx_irq, ldc_tx, 1251 IRQF_SAMPLE_RANDOM | IRQF_DISABLED | IRQF_SHARED, 1252 lp->tx_irq_name, lp); 1253 if (err) { 1254 free_irq(lp->cfg.rx_irq, lp); 1255 return err; 1256 } 1257 1258 1259 spin_lock_irqsave(&lp->lock, flags); 1260 1261 enable_irq(lp->cfg.rx_irq); 1262 enable_irq(lp->cfg.tx_irq); 1263 1264 lp->flags |= LDC_FLAG_REGISTERED_IRQS; 1265 1266 err = -ENODEV; 1267 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0); 1268 if (hv_err) 1269 goto out_free_irqs; 1270 1271 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries); 1272 if (hv_err) 1273 goto out_free_irqs; 1274 1275 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0); 1276 if (hv_err) 1277 goto out_unmap_tx; 1278 1279 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries); 1280 if (hv_err) 1281 goto out_unmap_tx; 1282 1283 lp->flags |= LDC_FLAG_REGISTERED_QUEUES; 1284 1285 hv_err = sun4v_ldc_tx_get_state(lp->id, 1286 &lp->tx_head, 1287 &lp->tx_tail, 1288 &lp->chan_state); 1289 err = -EBUSY; 1290 if (hv_err) 1291 goto out_unmap_rx; 1292 1293 lp->tx_acked = lp->tx_head; 1294 1295 lp->hs_state = LDC_HS_OPEN; 1296 ldc_set_state(lp, LDC_STATE_BOUND); 1297 1298 spin_unlock_irqrestore(&lp->lock, flags); 1299 1300 return 0; 1301 1302 out_unmap_rx: 1303 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES; 1304 sun4v_ldc_rx_qconf(lp->id, 0, 0); 1305 1306 out_unmap_tx: 1307 sun4v_ldc_tx_qconf(lp->id, 0, 0); 1308 1309 out_free_irqs: 1310 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS; 1311 free_irq(lp->cfg.tx_irq, lp); 1312 free_irq(lp->cfg.rx_irq, lp); 1313 1314 spin_unlock_irqrestore(&lp->lock, flags); 1315 1316 return err; 1317 } 1318 EXPORT_SYMBOL(ldc_bind); 1319 1320 int ldc_connect(struct ldc_channel *lp) 1321 { 1322 unsigned long flags; 1323 int err; 1324 1325 if (lp->cfg.mode == LDC_MODE_RAW) 1326 return -EINVAL; 1327 1328 spin_lock_irqsave(&lp->lock, flags); 1329 1330 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) || 1331 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES) || 1332 lp->hs_state != LDC_HS_OPEN) 1333 err = -EINVAL; 1334 else 1335 err = start_handshake(lp); 1336 1337 spin_unlock_irqrestore(&lp->lock, flags); 1338 1339 return err; 1340 } 1341 EXPORT_SYMBOL(ldc_connect); 1342 1343 int ldc_disconnect(struct ldc_channel *lp) 1344 { 1345 unsigned long hv_err, flags; 1346 int err; 1347 1348 if (lp->cfg.mode == LDC_MODE_RAW) 1349 return -EINVAL; 1350 1351 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) || 1352 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES)) 1353 return -EINVAL; 1354 1355 spin_lock_irqsave(&lp->lock, flags); 1356 1357 err = -ENODEV; 1358 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0); 1359 if (hv_err) 1360 goto out_err; 1361 1362 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries); 1363 if (hv_err) 1364 goto out_err; 1365 1366 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0); 1367 if (hv_err) 1368 goto out_err; 1369 1370 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries); 1371 if (hv_err) 1372 goto out_err; 1373 1374 ldc_set_state(lp, LDC_STATE_BOUND); 1375 lp->hs_state = LDC_HS_OPEN; 1376 lp->flags |= LDC_FLAG_RESET; 1377 1378 spin_unlock_irqrestore(&lp->lock, flags); 1379 1380 return 0; 1381 1382 out_err: 1383 sun4v_ldc_tx_qconf(lp->id, 0, 0); 1384 sun4v_ldc_rx_qconf(lp->id, 0, 0); 1385 free_irq(lp->cfg.tx_irq, lp); 1386 free_irq(lp->cfg.rx_irq, lp); 1387 lp->flags &= ~(LDC_FLAG_REGISTERED_IRQS | 1388 LDC_FLAG_REGISTERED_QUEUES); 1389 ldc_set_state(lp, LDC_STATE_INIT); 1390 1391 spin_unlock_irqrestore(&lp->lock, flags); 1392 1393 return err; 1394 } 1395 EXPORT_SYMBOL(ldc_disconnect); 1396 1397 int ldc_state(struct ldc_channel *lp) 1398 { 1399 return lp->state; 1400 } 1401 EXPORT_SYMBOL(ldc_state); 1402 1403 static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size) 1404 { 1405 struct ldc_packet *p; 1406 unsigned long new_tail; 1407 int err; 1408 1409 if (size > LDC_PACKET_SIZE) 1410 return -EMSGSIZE; 1411 1412 p = data_get_tx_packet(lp, &new_tail); 1413 if (!p) 1414 return -EAGAIN; 1415 1416 memcpy(p, buf, size); 1417 1418 err = send_tx_packet(lp, p, new_tail); 1419 if (!err) 1420 err = size; 1421 1422 return err; 1423 } 1424 1425 static int read_raw(struct ldc_channel *lp, void *buf, unsigned int size) 1426 { 1427 struct ldc_packet *p; 1428 unsigned long hv_err, new; 1429 int err; 1430 1431 if (size < LDC_PACKET_SIZE) 1432 return -EINVAL; 1433 1434 hv_err = sun4v_ldc_rx_get_state(lp->id, 1435 &lp->rx_head, 1436 &lp->rx_tail, 1437 &lp->chan_state); 1438 if (hv_err) 1439 return ldc_abort(lp); 1440 1441 if (lp->chan_state == LDC_CHANNEL_DOWN || 1442 lp->chan_state == LDC_CHANNEL_RESETTING) 1443 return -ECONNRESET; 1444 1445 if (lp->rx_head == lp->rx_tail) 1446 return 0; 1447 1448 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE); 1449 memcpy(buf, p, LDC_PACKET_SIZE); 1450 1451 new = rx_advance(lp, lp->rx_head); 1452 lp->rx_head = new; 1453 1454 err = __set_rx_head(lp, new); 1455 if (err < 0) 1456 err = -ECONNRESET; 1457 else 1458 err = LDC_PACKET_SIZE; 1459 1460 return err; 1461 } 1462 1463 static const struct ldc_mode_ops raw_ops = { 1464 .write = write_raw, 1465 .read = read_raw, 1466 }; 1467 1468 static int write_nonraw(struct ldc_channel *lp, const void *buf, 1469 unsigned int size) 1470 { 1471 unsigned long hv_err, tail; 1472 unsigned int copied; 1473 u32 seq; 1474 int err; 1475 1476 hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail, 1477 &lp->chan_state); 1478 if (unlikely(hv_err)) 1479 return -EBUSY; 1480 1481 if (unlikely(lp->chan_state != LDC_CHANNEL_UP)) 1482 return ldc_abort(lp); 1483 1484 if (!tx_has_space_for(lp, size)) 1485 return -EAGAIN; 1486 1487 seq = lp->snd_nxt; 1488 copied = 0; 1489 tail = lp->tx_tail; 1490 while (copied < size) { 1491 struct ldc_packet *p = lp->tx_base + (tail / LDC_PACKET_SIZE); 1492 u8 *data = ((lp->cfg.mode == LDC_MODE_UNRELIABLE) ? 1493 p->u.u_data : 1494 p->u.r.r_data); 1495 int data_len; 1496 1497 p->type = LDC_DATA; 1498 p->stype = LDC_INFO; 1499 p->ctrl = 0; 1500 1501 data_len = size - copied; 1502 if (data_len > lp->mss) 1503 data_len = lp->mss; 1504 1505 BUG_ON(data_len > LDC_LEN); 1506 1507 p->env = (data_len | 1508 (copied == 0 ? LDC_START : 0) | 1509 (data_len == size - copied ? LDC_STOP : 0)); 1510 1511 p->seqid = ++seq; 1512 1513 ldcdbg(DATA, "SENT DATA [%02x:%02x:%02x:%02x:%08x]\n", 1514 p->type, 1515 p->stype, 1516 p->ctrl, 1517 p->env, 1518 p->seqid); 1519 1520 memcpy(data, buf, data_len); 1521 buf += data_len; 1522 copied += data_len; 1523 1524 tail = tx_advance(lp, tail); 1525 } 1526 1527 err = set_tx_tail(lp, tail); 1528 if (!err) { 1529 lp->snd_nxt = seq; 1530 err = size; 1531 } 1532 1533 return err; 1534 } 1535 1536 static int rx_bad_seq(struct ldc_channel *lp, struct ldc_packet *p, 1537 struct ldc_packet *first_frag) 1538 { 1539 int err; 1540 1541 if (first_frag) 1542 lp->rcv_nxt = first_frag->seqid - 1; 1543 1544 err = send_data_nack(lp, p); 1545 if (err) 1546 return err; 1547 1548 err = __set_rx_head(lp, lp->rx_tail); 1549 if (err < 0) 1550 return ldc_abort(lp); 1551 1552 return 0; 1553 } 1554 1555 static int data_ack_nack(struct ldc_channel *lp, struct ldc_packet *p) 1556 { 1557 if (p->stype & LDC_ACK) { 1558 int err = process_data_ack(lp, p); 1559 if (err) 1560 return err; 1561 } 1562 if (p->stype & LDC_NACK) 1563 return ldc_abort(lp); 1564 1565 return 0; 1566 } 1567 1568 static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head) 1569 { 1570 unsigned long dummy; 1571 int limit = 1000; 1572 1573 ldcdbg(DATA, "DATA WAIT cur_head[%lx] rx_head[%lx] rx_tail[%lx]\n", 1574 cur_head, lp->rx_head, lp->rx_tail); 1575 while (limit-- > 0) { 1576 unsigned long hv_err; 1577 1578 hv_err = sun4v_ldc_rx_get_state(lp->id, 1579 &dummy, 1580 &lp->rx_tail, 1581 &lp->chan_state); 1582 if (hv_err) 1583 return ldc_abort(lp); 1584 1585 if (lp->chan_state == LDC_CHANNEL_DOWN || 1586 lp->chan_state == LDC_CHANNEL_RESETTING) 1587 return -ECONNRESET; 1588 1589 if (cur_head != lp->rx_tail) { 1590 ldcdbg(DATA, "DATA WAIT DONE " 1591 "head[%lx] tail[%lx] chan_state[%lx]\n", 1592 dummy, lp->rx_tail, lp->chan_state); 1593 return 0; 1594 } 1595 1596 udelay(1); 1597 } 1598 return -EAGAIN; 1599 } 1600 1601 static int rx_set_head(struct ldc_channel *lp, unsigned long head) 1602 { 1603 int err = __set_rx_head(lp, head); 1604 1605 if (err < 0) 1606 return ldc_abort(lp); 1607 1608 lp->rx_head = head; 1609 return 0; 1610 } 1611 1612 static void send_data_ack(struct ldc_channel *lp) 1613 { 1614 unsigned long new_tail; 1615 struct ldc_packet *p; 1616 1617 p = data_get_tx_packet(lp, &new_tail); 1618 if (likely(p)) { 1619 int err; 1620 1621 memset(p, 0, sizeof(*p)); 1622 p->type = LDC_DATA; 1623 p->stype = LDC_ACK; 1624 p->ctrl = 0; 1625 p->seqid = lp->snd_nxt + 1; 1626 p->u.r.ackid = lp->rcv_nxt; 1627 1628 err = send_tx_packet(lp, p, new_tail); 1629 if (!err) 1630 lp->snd_nxt++; 1631 } 1632 } 1633 1634 static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size) 1635 { 1636 struct ldc_packet *first_frag; 1637 unsigned long hv_err, new; 1638 int err, copied; 1639 1640 hv_err = sun4v_ldc_rx_get_state(lp->id, 1641 &lp->rx_head, 1642 &lp->rx_tail, 1643 &lp->chan_state); 1644 if (hv_err) 1645 return ldc_abort(lp); 1646 1647 if (lp->chan_state == LDC_CHANNEL_DOWN || 1648 lp->chan_state == LDC_CHANNEL_RESETTING) 1649 return -ECONNRESET; 1650 1651 if (lp->rx_head == lp->rx_tail) 1652 return 0; 1653 1654 first_frag = NULL; 1655 copied = err = 0; 1656 new = lp->rx_head; 1657 while (1) { 1658 struct ldc_packet *p; 1659 int pkt_len; 1660 1661 BUG_ON(new == lp->rx_tail); 1662 p = lp->rx_base + (new / LDC_PACKET_SIZE); 1663 1664 ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x:%08x] " 1665 "rcv_nxt[%08x]\n", 1666 p->type, 1667 p->stype, 1668 p->ctrl, 1669 p->env, 1670 p->seqid, 1671 p->u.r.ackid, 1672 lp->rcv_nxt); 1673 1674 if (unlikely(!rx_seq_ok(lp, p->seqid))) { 1675 err = rx_bad_seq(lp, p, first_frag); 1676 copied = 0; 1677 break; 1678 } 1679 1680 if (p->type & LDC_CTRL) { 1681 err = process_control_frame(lp, p); 1682 if (err < 0) 1683 break; 1684 err = 0; 1685 } 1686 1687 lp->rcv_nxt = p->seqid; 1688 1689 if (!(p->type & LDC_DATA)) { 1690 new = rx_advance(lp, new); 1691 goto no_data; 1692 } 1693 if (p->stype & (LDC_ACK | LDC_NACK)) { 1694 err = data_ack_nack(lp, p); 1695 if (err) 1696 break; 1697 } 1698 if (!(p->stype & LDC_INFO)) { 1699 new = rx_advance(lp, new); 1700 err = rx_set_head(lp, new); 1701 if (err) 1702 break; 1703 goto no_data; 1704 } 1705 1706 pkt_len = p->env & LDC_LEN; 1707 1708 /* Every initial packet starts with the START bit set. 1709 * 1710 * Singleton packets will have both START+STOP set. 1711 * 1712 * Fragments will have START set in the first frame, STOP 1713 * set in the last frame, and neither bit set in middle 1714 * frames of the packet. 1715 * 1716 * Therefore if we are at the beginning of a packet and 1717 * we don't see START, or we are in the middle of a fragmented 1718 * packet and do see START, we are unsynchronized and should 1719 * flush the RX queue. 1720 */ 1721 if ((first_frag == NULL && !(p->env & LDC_START)) || 1722 (first_frag != NULL && (p->env & LDC_START))) { 1723 if (!first_frag) 1724 new = rx_advance(lp, new); 1725 1726 err = rx_set_head(lp, new); 1727 if (err) 1728 break; 1729 1730 if (!first_frag) 1731 goto no_data; 1732 } 1733 if (!first_frag) 1734 first_frag = p; 1735 1736 if (pkt_len > size - copied) { 1737 /* User didn't give us a big enough buffer, 1738 * what to do? This is a pretty serious error. 1739 * 1740 * Since we haven't updated the RX ring head to 1741 * consume any of the packets, signal the error 1742 * to the user and just leave the RX ring alone. 1743 * 1744 * This seems the best behavior because this allows 1745 * a user of the LDC layer to start with a small 1746 * RX buffer for ldc_read() calls and use -EMSGSIZE 1747 * as a cue to enlarge it's read buffer. 1748 */ 1749 err = -EMSGSIZE; 1750 break; 1751 } 1752 1753 /* Ok, we are gonna eat this one. */ 1754 new = rx_advance(lp, new); 1755 1756 memcpy(buf, 1757 (lp->cfg.mode == LDC_MODE_UNRELIABLE ? 1758 p->u.u_data : p->u.r.r_data), pkt_len); 1759 buf += pkt_len; 1760 copied += pkt_len; 1761 1762 if (p->env & LDC_STOP) 1763 break; 1764 1765 no_data: 1766 if (new == lp->rx_tail) { 1767 err = rx_data_wait(lp, new); 1768 if (err) 1769 break; 1770 } 1771 } 1772 1773 if (!err) 1774 err = rx_set_head(lp, new); 1775 1776 if (err && first_frag) 1777 lp->rcv_nxt = first_frag->seqid - 1; 1778 1779 if (!err) { 1780 err = copied; 1781 if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE) 1782 send_data_ack(lp); 1783 } 1784 1785 return err; 1786 } 1787 1788 static const struct ldc_mode_ops nonraw_ops = { 1789 .write = write_nonraw, 1790 .read = read_nonraw, 1791 }; 1792 1793 static int write_stream(struct ldc_channel *lp, const void *buf, 1794 unsigned int size) 1795 { 1796 if (size > lp->cfg.mtu) 1797 size = lp->cfg.mtu; 1798 return write_nonraw(lp, buf, size); 1799 } 1800 1801 static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size) 1802 { 1803 if (!lp->mssbuf_len) { 1804 int err = read_nonraw(lp, lp->mssbuf, lp->cfg.mtu); 1805 if (err < 0) 1806 return err; 1807 1808 lp->mssbuf_len = err; 1809 lp->mssbuf_off = 0; 1810 } 1811 1812 if (size > lp->mssbuf_len) 1813 size = lp->mssbuf_len; 1814 memcpy(buf, lp->mssbuf + lp->mssbuf_off, size); 1815 1816 lp->mssbuf_off += size; 1817 lp->mssbuf_len -= size; 1818 1819 return size; 1820 } 1821 1822 static const struct ldc_mode_ops stream_ops = { 1823 .write = write_stream, 1824 .read = read_stream, 1825 }; 1826 1827 int ldc_write(struct ldc_channel *lp, const void *buf, unsigned int size) 1828 { 1829 unsigned long flags; 1830 int err; 1831 1832 if (!buf) 1833 return -EINVAL; 1834 1835 if (!size) 1836 return 0; 1837 1838 spin_lock_irqsave(&lp->lock, flags); 1839 1840 if (lp->hs_state != LDC_HS_COMPLETE) 1841 err = -ENOTCONN; 1842 else 1843 err = lp->mops->write(lp, buf, size); 1844 1845 spin_unlock_irqrestore(&lp->lock, flags); 1846 1847 return err; 1848 } 1849 EXPORT_SYMBOL(ldc_write); 1850 1851 int ldc_read(struct ldc_channel *lp, void *buf, unsigned int size) 1852 { 1853 unsigned long flags; 1854 int err; 1855 1856 if (!buf) 1857 return -EINVAL; 1858 1859 if (!size) 1860 return 0; 1861 1862 spin_lock_irqsave(&lp->lock, flags); 1863 1864 if (lp->hs_state != LDC_HS_COMPLETE) 1865 err = -ENOTCONN; 1866 else 1867 err = lp->mops->read(lp, buf, size); 1868 1869 spin_unlock_irqrestore(&lp->lock, flags); 1870 1871 return err; 1872 } 1873 EXPORT_SYMBOL(ldc_read); 1874 1875 static long arena_alloc(struct ldc_iommu *iommu, unsigned long npages) 1876 { 1877 struct iommu_arena *arena = &iommu->arena; 1878 unsigned long n, i, start, end, limit; 1879 int pass; 1880 1881 limit = arena->limit; 1882 start = arena->hint; 1883 pass = 0; 1884 1885 again: 1886 n = find_next_zero_bit(arena->map, limit, start); 1887 end = n + npages; 1888 if (unlikely(end >= limit)) { 1889 if (likely(pass < 1)) { 1890 limit = start; 1891 start = 0; 1892 pass++; 1893 goto again; 1894 } else { 1895 /* Scanned the whole thing, give up. */ 1896 return -1; 1897 } 1898 } 1899 1900 for (i = n; i < end; i++) { 1901 if (test_bit(i, arena->map)) { 1902 start = i + 1; 1903 goto again; 1904 } 1905 } 1906 1907 for (i = n; i < end; i++) 1908 __set_bit(i, arena->map); 1909 1910 arena->hint = end; 1911 1912 return n; 1913 } 1914 1915 #define COOKIE_PGSZ_CODE 0xf000000000000000ULL 1916 #define COOKIE_PGSZ_CODE_SHIFT 60ULL 1917 1918 static u64 pagesize_code(void) 1919 { 1920 switch (PAGE_SIZE) { 1921 default: 1922 case (8ULL * 1024ULL): 1923 return 0; 1924 case (64ULL * 1024ULL): 1925 return 1; 1926 case (512ULL * 1024ULL): 1927 return 2; 1928 case (4ULL * 1024ULL * 1024ULL): 1929 return 3; 1930 case (32ULL * 1024ULL * 1024ULL): 1931 return 4; 1932 case (256ULL * 1024ULL * 1024ULL): 1933 return 5; 1934 } 1935 } 1936 1937 static u64 make_cookie(u64 index, u64 pgsz_code, u64 page_offset) 1938 { 1939 return ((pgsz_code << COOKIE_PGSZ_CODE_SHIFT) | 1940 (index << PAGE_SHIFT) | 1941 page_offset); 1942 } 1943 1944 static u64 cookie_to_index(u64 cookie, unsigned long *shift) 1945 { 1946 u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT; 1947 1948 cookie &= ~COOKIE_PGSZ_CODE; 1949 1950 *shift = szcode * 3; 1951 1952 return (cookie >> (13ULL + (szcode * 3ULL))); 1953 } 1954 1955 static struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu, 1956 unsigned long npages) 1957 { 1958 long entry; 1959 1960 entry = arena_alloc(iommu, npages); 1961 if (unlikely(entry < 0)) 1962 return NULL; 1963 1964 return iommu->page_table + entry; 1965 } 1966 1967 static u64 perm_to_mte(unsigned int map_perm) 1968 { 1969 u64 mte_base; 1970 1971 mte_base = pagesize_code(); 1972 1973 if (map_perm & LDC_MAP_SHADOW) { 1974 if (map_perm & LDC_MAP_R) 1975 mte_base |= LDC_MTE_COPY_R; 1976 if (map_perm & LDC_MAP_W) 1977 mte_base |= LDC_MTE_COPY_W; 1978 } 1979 if (map_perm & LDC_MAP_DIRECT) { 1980 if (map_perm & LDC_MAP_R) 1981 mte_base |= LDC_MTE_READ; 1982 if (map_perm & LDC_MAP_W) 1983 mte_base |= LDC_MTE_WRITE; 1984 if (map_perm & LDC_MAP_X) 1985 mte_base |= LDC_MTE_EXEC; 1986 } 1987 if (map_perm & LDC_MAP_IO) { 1988 if (map_perm & LDC_MAP_R) 1989 mte_base |= LDC_MTE_IOMMU_R; 1990 if (map_perm & LDC_MAP_W) 1991 mte_base |= LDC_MTE_IOMMU_W; 1992 } 1993 1994 return mte_base; 1995 } 1996 1997 static int pages_in_region(unsigned long base, long len) 1998 { 1999 int count = 0; 2000 2001 do { 2002 unsigned long new = (base + PAGE_SIZE) & PAGE_MASK; 2003 2004 len -= (new - base); 2005 base = new; 2006 count++; 2007 } while (len > 0); 2008 2009 return count; 2010 } 2011 2012 struct cookie_state { 2013 struct ldc_mtable_entry *page_table; 2014 struct ldc_trans_cookie *cookies; 2015 u64 mte_base; 2016 u64 prev_cookie; 2017 u32 pte_idx; 2018 u32 nc; 2019 }; 2020 2021 static void fill_cookies(struct cookie_state *sp, unsigned long pa, 2022 unsigned long off, unsigned long len) 2023 { 2024 do { 2025 unsigned long tlen, new = pa + PAGE_SIZE; 2026 u64 this_cookie; 2027 2028 sp->page_table[sp->pte_idx].mte = sp->mte_base | pa; 2029 2030 tlen = PAGE_SIZE; 2031 if (off) 2032 tlen = PAGE_SIZE - off; 2033 if (tlen > len) 2034 tlen = len; 2035 2036 this_cookie = make_cookie(sp->pte_idx, 2037 pagesize_code(), off); 2038 2039 off = 0; 2040 2041 if (this_cookie == sp->prev_cookie) { 2042 sp->cookies[sp->nc - 1].cookie_size += tlen; 2043 } else { 2044 sp->cookies[sp->nc].cookie_addr = this_cookie; 2045 sp->cookies[sp->nc].cookie_size = tlen; 2046 sp->nc++; 2047 } 2048 sp->prev_cookie = this_cookie + tlen; 2049 2050 sp->pte_idx++; 2051 2052 len -= tlen; 2053 pa = new; 2054 } while (len > 0); 2055 } 2056 2057 static int sg_count_one(struct scatterlist *sg) 2058 { 2059 unsigned long base = page_to_pfn(sg_page(sg)) << PAGE_SHIFT; 2060 long len = sg->length; 2061 2062 if ((sg->offset | len) & (8UL - 1)) 2063 return -EFAULT; 2064 2065 return pages_in_region(base + sg->offset, len); 2066 } 2067 2068 static int sg_count_pages(struct scatterlist *sg, int num_sg) 2069 { 2070 int count; 2071 int i; 2072 2073 count = 0; 2074 for (i = 0; i < num_sg; i++) { 2075 int err = sg_count_one(sg + i); 2076 if (err < 0) 2077 return err; 2078 count += err; 2079 } 2080 2081 return count; 2082 } 2083 2084 int ldc_map_sg(struct ldc_channel *lp, 2085 struct scatterlist *sg, int num_sg, 2086 struct ldc_trans_cookie *cookies, int ncookies, 2087 unsigned int map_perm) 2088 { 2089 unsigned long i, npages, flags; 2090 struct ldc_mtable_entry *base; 2091 struct cookie_state state; 2092 struct ldc_iommu *iommu; 2093 int err; 2094 2095 if (map_perm & ~LDC_MAP_ALL) 2096 return -EINVAL; 2097 2098 err = sg_count_pages(sg, num_sg); 2099 if (err < 0) 2100 return err; 2101 2102 npages = err; 2103 if (err > ncookies) 2104 return -EMSGSIZE; 2105 2106 iommu = &lp->iommu; 2107 2108 spin_lock_irqsave(&iommu->lock, flags); 2109 base = alloc_npages(iommu, npages); 2110 spin_unlock_irqrestore(&iommu->lock, flags); 2111 2112 if (!base) 2113 return -ENOMEM; 2114 2115 state.page_table = iommu->page_table; 2116 state.cookies = cookies; 2117 state.mte_base = perm_to_mte(map_perm); 2118 state.prev_cookie = ~(u64)0; 2119 state.pte_idx = (base - iommu->page_table); 2120 state.nc = 0; 2121 2122 for (i = 0; i < num_sg; i++) 2123 fill_cookies(&state, page_to_pfn(sg_page(&sg[i])) << PAGE_SHIFT, 2124 sg[i].offset, sg[i].length); 2125 2126 return state.nc; 2127 } 2128 EXPORT_SYMBOL(ldc_map_sg); 2129 2130 int ldc_map_single(struct ldc_channel *lp, 2131 void *buf, unsigned int len, 2132 struct ldc_trans_cookie *cookies, int ncookies, 2133 unsigned int map_perm) 2134 { 2135 unsigned long npages, pa, flags; 2136 struct ldc_mtable_entry *base; 2137 struct cookie_state state; 2138 struct ldc_iommu *iommu; 2139 2140 if ((map_perm & ~LDC_MAP_ALL) || (ncookies < 1)) 2141 return -EINVAL; 2142 2143 pa = __pa(buf); 2144 if ((pa | len) & (8UL - 1)) 2145 return -EFAULT; 2146 2147 npages = pages_in_region(pa, len); 2148 2149 iommu = &lp->iommu; 2150 2151 spin_lock_irqsave(&iommu->lock, flags); 2152 base = alloc_npages(iommu, npages); 2153 spin_unlock_irqrestore(&iommu->lock, flags); 2154 2155 if (!base) 2156 return -ENOMEM; 2157 2158 state.page_table = iommu->page_table; 2159 state.cookies = cookies; 2160 state.mte_base = perm_to_mte(map_perm); 2161 state.prev_cookie = ~(u64)0; 2162 state.pte_idx = (base - iommu->page_table); 2163 state.nc = 0; 2164 fill_cookies(&state, (pa & PAGE_MASK), (pa & ~PAGE_MASK), len); 2165 BUG_ON(state.nc != 1); 2166 2167 return state.nc; 2168 } 2169 EXPORT_SYMBOL(ldc_map_single); 2170 2171 static void free_npages(unsigned long id, struct ldc_iommu *iommu, 2172 u64 cookie, u64 size) 2173 { 2174 struct iommu_arena *arena = &iommu->arena; 2175 unsigned long i, shift, index, npages; 2176 struct ldc_mtable_entry *base; 2177 2178 npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT; 2179 index = cookie_to_index(cookie, &shift); 2180 base = iommu->page_table + index; 2181 2182 BUG_ON(index > arena->limit || 2183 (index + npages) > arena->limit); 2184 2185 for (i = 0; i < npages; i++) { 2186 if (base->cookie) 2187 sun4v_ldc_revoke(id, cookie + (i << shift), 2188 base->cookie); 2189 base->mte = 0; 2190 __clear_bit(index + i, arena->map); 2191 } 2192 } 2193 2194 void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies, 2195 int ncookies) 2196 { 2197 struct ldc_iommu *iommu = &lp->iommu; 2198 unsigned long flags; 2199 int i; 2200 2201 spin_lock_irqsave(&iommu->lock, flags); 2202 for (i = 0; i < ncookies; i++) { 2203 u64 addr = cookies[i].cookie_addr; 2204 u64 size = cookies[i].cookie_size; 2205 2206 free_npages(lp->id, iommu, addr, size); 2207 } 2208 spin_unlock_irqrestore(&iommu->lock, flags); 2209 } 2210 EXPORT_SYMBOL(ldc_unmap); 2211 2212 int ldc_copy(struct ldc_channel *lp, int copy_dir, 2213 void *buf, unsigned int len, unsigned long offset, 2214 struct ldc_trans_cookie *cookies, int ncookies) 2215 { 2216 unsigned int orig_len; 2217 unsigned long ra; 2218 int i; 2219 2220 if (copy_dir != LDC_COPY_IN && copy_dir != LDC_COPY_OUT) { 2221 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Bad copy_dir[%d]\n", 2222 lp->id, copy_dir); 2223 return -EINVAL; 2224 } 2225 2226 ra = __pa(buf); 2227 if ((ra | len | offset) & (8UL - 1)) { 2228 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Unaligned buffer " 2229 "ra[%lx] len[%x] offset[%lx]\n", 2230 lp->id, ra, len, offset); 2231 return -EFAULT; 2232 } 2233 2234 if (lp->hs_state != LDC_HS_COMPLETE || 2235 (lp->flags & LDC_FLAG_RESET)) { 2236 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Link down hs_state[%x] " 2237 "flags[%x]\n", lp->id, lp->hs_state, lp->flags); 2238 return -ECONNRESET; 2239 } 2240 2241 orig_len = len; 2242 for (i = 0; i < ncookies; i++) { 2243 unsigned long cookie_raddr = cookies[i].cookie_addr; 2244 unsigned long this_len = cookies[i].cookie_size; 2245 unsigned long actual_len; 2246 2247 if (unlikely(offset)) { 2248 unsigned long this_off = offset; 2249 2250 if (this_off > this_len) 2251 this_off = this_len; 2252 2253 offset -= this_off; 2254 this_len -= this_off; 2255 if (!this_len) 2256 continue; 2257 cookie_raddr += this_off; 2258 } 2259 2260 if (this_len > len) 2261 this_len = len; 2262 2263 while (1) { 2264 unsigned long hv_err; 2265 2266 hv_err = sun4v_ldc_copy(lp->id, copy_dir, 2267 cookie_raddr, ra, 2268 this_len, &actual_len); 2269 if (unlikely(hv_err)) { 2270 printk(KERN_ERR PFX "ldc_copy: ID[%lu] " 2271 "HV error %lu\n", 2272 lp->id, hv_err); 2273 if (lp->hs_state != LDC_HS_COMPLETE || 2274 (lp->flags & LDC_FLAG_RESET)) 2275 return -ECONNRESET; 2276 else 2277 return -EFAULT; 2278 } 2279 2280 cookie_raddr += actual_len; 2281 ra += actual_len; 2282 len -= actual_len; 2283 if (actual_len == this_len) 2284 break; 2285 2286 this_len -= actual_len; 2287 } 2288 2289 if (!len) 2290 break; 2291 } 2292 2293 /* It is caller policy what to do about short copies. 2294 * For example, a networking driver can declare the 2295 * packet a runt and drop it. 2296 */ 2297 2298 return orig_len - len; 2299 } 2300 EXPORT_SYMBOL(ldc_copy); 2301 2302 void *ldc_alloc_exp_dring(struct ldc_channel *lp, unsigned int len, 2303 struct ldc_trans_cookie *cookies, int *ncookies, 2304 unsigned int map_perm) 2305 { 2306 void *buf; 2307 int err; 2308 2309 if (len & (8UL - 1)) 2310 return ERR_PTR(-EINVAL); 2311 2312 buf = kzalloc(len, GFP_KERNEL); 2313 if (!buf) 2314 return ERR_PTR(-ENOMEM); 2315 2316 err = ldc_map_single(lp, buf, len, cookies, *ncookies, map_perm); 2317 if (err < 0) { 2318 kfree(buf); 2319 return ERR_PTR(err); 2320 } 2321 *ncookies = err; 2322 2323 return buf; 2324 } 2325 EXPORT_SYMBOL(ldc_alloc_exp_dring); 2326 2327 void ldc_free_exp_dring(struct ldc_channel *lp, void *buf, unsigned int len, 2328 struct ldc_trans_cookie *cookies, int ncookies) 2329 { 2330 ldc_unmap(lp, cookies, ncookies); 2331 kfree(buf); 2332 } 2333 EXPORT_SYMBOL(ldc_free_exp_dring); 2334 2335 static int __init ldc_init(void) 2336 { 2337 unsigned long major, minor; 2338 struct mdesc_handle *hp; 2339 const u64 *v; 2340 int err; 2341 u64 mp; 2342 2343 hp = mdesc_grab(); 2344 if (!hp) 2345 return -ENODEV; 2346 2347 mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform"); 2348 err = -ENODEV; 2349 if (mp == MDESC_NODE_NULL) 2350 goto out; 2351 2352 v = mdesc_get_property(hp, mp, "domaining-enabled", NULL); 2353 if (!v) 2354 goto out; 2355 2356 major = 1; 2357 minor = 0; 2358 if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) { 2359 printk(KERN_INFO PFX "Could not register LDOM hvapi.\n"); 2360 goto out; 2361 } 2362 2363 printk(KERN_INFO "%s", version); 2364 2365 if (!*v) { 2366 printk(KERN_INFO PFX "Domaining disabled.\n"); 2367 goto out; 2368 } 2369 ldom_domaining_enabled = 1; 2370 err = 0; 2371 2372 out: 2373 mdesc_release(hp); 2374 return err; 2375 } 2376 2377 core_initcall(ldc_init); 2378