1 /* ldc.c: Logical Domain Channel link-layer protocol driver. 2 * 3 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net> 4 */ 5 6 #include <linux/kernel.h> 7 #include <linux/export.h> 8 #include <linux/slab.h> 9 #include <linux/spinlock.h> 10 #include <linux/delay.h> 11 #include <linux/errno.h> 12 #include <linux/string.h> 13 #include <linux/scatterlist.h> 14 #include <linux/interrupt.h> 15 #include <linux/list.h> 16 #include <linux/init.h> 17 #include <linux/bitmap.h> 18 19 #include <asm/hypervisor.h> 20 #include <asm/iommu.h> 21 #include <asm/page.h> 22 #include <asm/ldc.h> 23 #include <asm/mdesc.h> 24 25 #define DRV_MODULE_NAME "ldc" 26 #define PFX DRV_MODULE_NAME ": " 27 #define DRV_MODULE_VERSION "1.1" 28 #define DRV_MODULE_RELDATE "July 22, 2008" 29 30 static char version[] = 31 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n"; 32 #define LDC_PACKET_SIZE 64 33 34 /* Packet header layout for unreliable and reliable mode frames. 35 * When in RAW mode, packets are simply straight 64-byte payloads 36 * with no headers. 37 */ 38 struct ldc_packet { 39 u8 type; 40 #define LDC_CTRL 0x01 41 #define LDC_DATA 0x02 42 #define LDC_ERR 0x10 43 44 u8 stype; 45 #define LDC_INFO 0x01 46 #define LDC_ACK 0x02 47 #define LDC_NACK 0x04 48 49 u8 ctrl; 50 #define LDC_VERS 0x01 /* Link Version */ 51 #define LDC_RTS 0x02 /* Request To Send */ 52 #define LDC_RTR 0x03 /* Ready To Receive */ 53 #define LDC_RDX 0x04 /* Ready for Data eXchange */ 54 #define LDC_CTRL_MSK 0x0f 55 56 u8 env; 57 #define LDC_LEN 0x3f 58 #define LDC_FRAG_MASK 0xc0 59 #define LDC_START 0x40 60 #define LDC_STOP 0x80 61 62 u32 seqid; 63 64 union { 65 u8 u_data[LDC_PACKET_SIZE - 8]; 66 struct { 67 u32 pad; 68 u32 ackid; 69 u8 r_data[LDC_PACKET_SIZE - 8 - 8]; 70 } r; 71 } u; 72 }; 73 74 struct ldc_version { 75 u16 major; 76 u16 minor; 77 }; 78 79 /* Ordered from largest major to lowest. */ 80 static struct ldc_version ver_arr[] = { 81 { .major = 1, .minor = 0 }, 82 }; 83 84 #define LDC_DEFAULT_MTU (4 * LDC_PACKET_SIZE) 85 #define LDC_DEFAULT_NUM_ENTRIES (PAGE_SIZE / LDC_PACKET_SIZE) 86 87 struct ldc_channel; 88 89 struct ldc_mode_ops { 90 int (*write)(struct ldc_channel *, const void *, unsigned int); 91 int (*read)(struct ldc_channel *, void *, unsigned int); 92 }; 93 94 static const struct ldc_mode_ops raw_ops; 95 static const struct ldc_mode_ops nonraw_ops; 96 static const struct ldc_mode_ops stream_ops; 97 98 int ldom_domaining_enabled; 99 100 struct ldc_iommu { 101 /* Protects arena alloc/free. */ 102 spinlock_t lock; 103 struct iommu_arena arena; 104 struct ldc_mtable_entry *page_table; 105 }; 106 107 struct ldc_channel { 108 /* Protects all operations that depend upon channel state. */ 109 spinlock_t lock; 110 111 unsigned long id; 112 113 u8 *mssbuf; 114 u32 mssbuf_len; 115 u32 mssbuf_off; 116 117 struct ldc_packet *tx_base; 118 unsigned long tx_head; 119 unsigned long tx_tail; 120 unsigned long tx_num_entries; 121 unsigned long tx_ra; 122 123 unsigned long tx_acked; 124 125 struct ldc_packet *rx_base; 126 unsigned long rx_head; 127 unsigned long rx_tail; 128 unsigned long rx_num_entries; 129 unsigned long rx_ra; 130 131 u32 rcv_nxt; 132 u32 snd_nxt; 133 134 unsigned long chan_state; 135 136 struct ldc_channel_config cfg; 137 void *event_arg; 138 139 const struct ldc_mode_ops *mops; 140 141 struct ldc_iommu iommu; 142 143 struct ldc_version ver; 144 145 u8 hs_state; 146 #define LDC_HS_CLOSED 0x00 147 #define LDC_HS_OPEN 0x01 148 #define LDC_HS_GOTVERS 0x02 149 #define LDC_HS_SENTRTR 0x03 150 #define LDC_HS_GOTRTR 0x04 151 #define LDC_HS_COMPLETE 0x10 152 153 u8 flags; 154 #define LDC_FLAG_ALLOCED_QUEUES 0x01 155 #define LDC_FLAG_REGISTERED_QUEUES 0x02 156 #define LDC_FLAG_REGISTERED_IRQS 0x04 157 #define LDC_FLAG_RESET 0x10 158 159 u8 mss; 160 u8 state; 161 162 #define LDC_IRQ_NAME_MAX 32 163 char rx_irq_name[LDC_IRQ_NAME_MAX]; 164 char tx_irq_name[LDC_IRQ_NAME_MAX]; 165 166 struct hlist_head mh_list; 167 168 struct hlist_node list; 169 }; 170 171 #define ldcdbg(TYPE, f, a...) \ 172 do { if (lp->cfg.debug & LDC_DEBUG_##TYPE) \ 173 printk(KERN_INFO PFX "ID[%lu] " f, lp->id, ## a); \ 174 } while (0) 175 176 static const char *state_to_str(u8 state) 177 { 178 switch (state) { 179 case LDC_STATE_INVALID: 180 return "INVALID"; 181 case LDC_STATE_INIT: 182 return "INIT"; 183 case LDC_STATE_BOUND: 184 return "BOUND"; 185 case LDC_STATE_READY: 186 return "READY"; 187 case LDC_STATE_CONNECTED: 188 return "CONNECTED"; 189 default: 190 return "<UNKNOWN>"; 191 } 192 } 193 194 static void ldc_set_state(struct ldc_channel *lp, u8 state) 195 { 196 ldcdbg(STATE, "STATE (%s) --> (%s)\n", 197 state_to_str(lp->state), 198 state_to_str(state)); 199 200 lp->state = state; 201 } 202 203 static unsigned long __advance(unsigned long off, unsigned long num_entries) 204 { 205 off += LDC_PACKET_SIZE; 206 if (off == (num_entries * LDC_PACKET_SIZE)) 207 off = 0; 208 209 return off; 210 } 211 212 static unsigned long rx_advance(struct ldc_channel *lp, unsigned long off) 213 { 214 return __advance(off, lp->rx_num_entries); 215 } 216 217 static unsigned long tx_advance(struct ldc_channel *lp, unsigned long off) 218 { 219 return __advance(off, lp->tx_num_entries); 220 } 221 222 static struct ldc_packet *handshake_get_tx_packet(struct ldc_channel *lp, 223 unsigned long *new_tail) 224 { 225 struct ldc_packet *p; 226 unsigned long t; 227 228 t = tx_advance(lp, lp->tx_tail); 229 if (t == lp->tx_head) 230 return NULL; 231 232 *new_tail = t; 233 234 p = lp->tx_base; 235 return p + (lp->tx_tail / LDC_PACKET_SIZE); 236 } 237 238 /* When we are in reliable or stream mode, have to track the next packet 239 * we haven't gotten an ACK for in the TX queue using tx_acked. We have 240 * to be careful not to stomp over the queue past that point. During 241 * the handshake, we don't have TX data packets pending in the queue 242 * and that's why handshake_get_tx_packet() need not be mindful of 243 * lp->tx_acked. 244 */ 245 static unsigned long head_for_data(struct ldc_channel *lp) 246 { 247 if (lp->cfg.mode == LDC_MODE_STREAM) 248 return lp->tx_acked; 249 return lp->tx_head; 250 } 251 252 static int tx_has_space_for(struct ldc_channel *lp, unsigned int size) 253 { 254 unsigned long limit, tail, new_tail, diff; 255 unsigned int mss; 256 257 limit = head_for_data(lp); 258 tail = lp->tx_tail; 259 new_tail = tx_advance(lp, tail); 260 if (new_tail == limit) 261 return 0; 262 263 if (limit > new_tail) 264 diff = limit - new_tail; 265 else 266 diff = (limit + 267 ((lp->tx_num_entries * LDC_PACKET_SIZE) - new_tail)); 268 diff /= LDC_PACKET_SIZE; 269 mss = lp->mss; 270 271 if (diff * mss < size) 272 return 0; 273 274 return 1; 275 } 276 277 static struct ldc_packet *data_get_tx_packet(struct ldc_channel *lp, 278 unsigned long *new_tail) 279 { 280 struct ldc_packet *p; 281 unsigned long h, t; 282 283 h = head_for_data(lp); 284 t = tx_advance(lp, lp->tx_tail); 285 if (t == h) 286 return NULL; 287 288 *new_tail = t; 289 290 p = lp->tx_base; 291 return p + (lp->tx_tail / LDC_PACKET_SIZE); 292 } 293 294 static int set_tx_tail(struct ldc_channel *lp, unsigned long tail) 295 { 296 unsigned long orig_tail = lp->tx_tail; 297 int limit = 1000; 298 299 lp->tx_tail = tail; 300 while (limit-- > 0) { 301 unsigned long err; 302 303 err = sun4v_ldc_tx_set_qtail(lp->id, tail); 304 if (!err) 305 return 0; 306 307 if (err != HV_EWOULDBLOCK) { 308 lp->tx_tail = orig_tail; 309 return -EINVAL; 310 } 311 udelay(1); 312 } 313 314 lp->tx_tail = orig_tail; 315 return -EBUSY; 316 } 317 318 /* This just updates the head value in the hypervisor using 319 * a polling loop with a timeout. The caller takes care of 320 * upating software state representing the head change, if any. 321 */ 322 static int __set_rx_head(struct ldc_channel *lp, unsigned long head) 323 { 324 int limit = 1000; 325 326 while (limit-- > 0) { 327 unsigned long err; 328 329 err = sun4v_ldc_rx_set_qhead(lp->id, head); 330 if (!err) 331 return 0; 332 333 if (err != HV_EWOULDBLOCK) 334 return -EINVAL; 335 336 udelay(1); 337 } 338 339 return -EBUSY; 340 } 341 342 static int send_tx_packet(struct ldc_channel *lp, 343 struct ldc_packet *p, 344 unsigned long new_tail) 345 { 346 BUG_ON(p != (lp->tx_base + (lp->tx_tail / LDC_PACKET_SIZE))); 347 348 return set_tx_tail(lp, new_tail); 349 } 350 351 static struct ldc_packet *handshake_compose_ctrl(struct ldc_channel *lp, 352 u8 stype, u8 ctrl, 353 void *data, int dlen, 354 unsigned long *new_tail) 355 { 356 struct ldc_packet *p = handshake_get_tx_packet(lp, new_tail); 357 358 if (p) { 359 memset(p, 0, sizeof(*p)); 360 p->type = LDC_CTRL; 361 p->stype = stype; 362 p->ctrl = ctrl; 363 if (data) 364 memcpy(p->u.u_data, data, dlen); 365 } 366 return p; 367 } 368 369 static int start_handshake(struct ldc_channel *lp) 370 { 371 struct ldc_packet *p; 372 struct ldc_version *ver; 373 unsigned long new_tail; 374 375 ver = &ver_arr[0]; 376 377 ldcdbg(HS, "SEND VER INFO maj[%u] min[%u]\n", 378 ver->major, ver->minor); 379 380 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS, 381 ver, sizeof(*ver), &new_tail); 382 if (p) { 383 int err = send_tx_packet(lp, p, new_tail); 384 if (!err) 385 lp->flags &= ~LDC_FLAG_RESET; 386 return err; 387 } 388 return -EBUSY; 389 } 390 391 static int send_version_nack(struct ldc_channel *lp, 392 u16 major, u16 minor) 393 { 394 struct ldc_packet *p; 395 struct ldc_version ver; 396 unsigned long new_tail; 397 398 ver.major = major; 399 ver.minor = minor; 400 401 p = handshake_compose_ctrl(lp, LDC_NACK, LDC_VERS, 402 &ver, sizeof(ver), &new_tail); 403 if (p) { 404 ldcdbg(HS, "SEND VER NACK maj[%u] min[%u]\n", 405 ver.major, ver.minor); 406 407 return send_tx_packet(lp, p, new_tail); 408 } 409 return -EBUSY; 410 } 411 412 static int send_version_ack(struct ldc_channel *lp, 413 struct ldc_version *vp) 414 { 415 struct ldc_packet *p; 416 unsigned long new_tail; 417 418 p = handshake_compose_ctrl(lp, LDC_ACK, LDC_VERS, 419 vp, sizeof(*vp), &new_tail); 420 if (p) { 421 ldcdbg(HS, "SEND VER ACK maj[%u] min[%u]\n", 422 vp->major, vp->minor); 423 424 return send_tx_packet(lp, p, new_tail); 425 } 426 return -EBUSY; 427 } 428 429 static int send_rts(struct ldc_channel *lp) 430 { 431 struct ldc_packet *p; 432 unsigned long new_tail; 433 434 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTS, NULL, 0, 435 &new_tail); 436 if (p) { 437 p->env = lp->cfg.mode; 438 p->seqid = 0; 439 lp->rcv_nxt = 0; 440 441 ldcdbg(HS, "SEND RTS env[0x%x] seqid[0x%x]\n", 442 p->env, p->seqid); 443 444 return send_tx_packet(lp, p, new_tail); 445 } 446 return -EBUSY; 447 } 448 449 static int send_rtr(struct ldc_channel *lp) 450 { 451 struct ldc_packet *p; 452 unsigned long new_tail; 453 454 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTR, NULL, 0, 455 &new_tail); 456 if (p) { 457 p->env = lp->cfg.mode; 458 p->seqid = 0; 459 460 ldcdbg(HS, "SEND RTR env[0x%x] seqid[0x%x]\n", 461 p->env, p->seqid); 462 463 return send_tx_packet(lp, p, new_tail); 464 } 465 return -EBUSY; 466 } 467 468 static int send_rdx(struct ldc_channel *lp) 469 { 470 struct ldc_packet *p; 471 unsigned long new_tail; 472 473 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RDX, NULL, 0, 474 &new_tail); 475 if (p) { 476 p->env = 0; 477 p->seqid = ++lp->snd_nxt; 478 p->u.r.ackid = lp->rcv_nxt; 479 480 ldcdbg(HS, "SEND RDX env[0x%x] seqid[0x%x] ackid[0x%x]\n", 481 p->env, p->seqid, p->u.r.ackid); 482 483 return send_tx_packet(lp, p, new_tail); 484 } 485 return -EBUSY; 486 } 487 488 static int send_data_nack(struct ldc_channel *lp, struct ldc_packet *data_pkt) 489 { 490 struct ldc_packet *p; 491 unsigned long new_tail; 492 int err; 493 494 p = data_get_tx_packet(lp, &new_tail); 495 if (!p) 496 return -EBUSY; 497 memset(p, 0, sizeof(*p)); 498 p->type = data_pkt->type; 499 p->stype = LDC_NACK; 500 p->ctrl = data_pkt->ctrl & LDC_CTRL_MSK; 501 p->seqid = lp->snd_nxt + 1; 502 p->u.r.ackid = lp->rcv_nxt; 503 504 ldcdbg(HS, "SEND DATA NACK type[0x%x] ctl[0x%x] seq[0x%x] ack[0x%x]\n", 505 p->type, p->ctrl, p->seqid, p->u.r.ackid); 506 507 err = send_tx_packet(lp, p, new_tail); 508 if (!err) 509 lp->snd_nxt++; 510 511 return err; 512 } 513 514 static int ldc_abort(struct ldc_channel *lp) 515 { 516 unsigned long hv_err; 517 518 ldcdbg(STATE, "ABORT\n"); 519 520 /* We report but do not act upon the hypervisor errors because 521 * there really isn't much we can do if they fail at this point. 522 */ 523 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries); 524 if (hv_err) 525 printk(KERN_ERR PFX "ldc_abort: " 526 "sun4v_ldc_tx_qconf(%lx,%lx,%lx) failed, err=%lu\n", 527 lp->id, lp->tx_ra, lp->tx_num_entries, hv_err); 528 529 hv_err = sun4v_ldc_tx_get_state(lp->id, 530 &lp->tx_head, 531 &lp->tx_tail, 532 &lp->chan_state); 533 if (hv_err) 534 printk(KERN_ERR PFX "ldc_abort: " 535 "sun4v_ldc_tx_get_state(%lx,...) failed, err=%lu\n", 536 lp->id, hv_err); 537 538 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries); 539 if (hv_err) 540 printk(KERN_ERR PFX "ldc_abort: " 541 "sun4v_ldc_rx_qconf(%lx,%lx,%lx) failed, err=%lu\n", 542 lp->id, lp->rx_ra, lp->rx_num_entries, hv_err); 543 544 /* Refetch the RX queue state as well, because we could be invoked 545 * here in the queue processing context. 546 */ 547 hv_err = sun4v_ldc_rx_get_state(lp->id, 548 &lp->rx_head, 549 &lp->rx_tail, 550 &lp->chan_state); 551 if (hv_err) 552 printk(KERN_ERR PFX "ldc_abort: " 553 "sun4v_ldc_rx_get_state(%lx,...) failed, err=%lu\n", 554 lp->id, hv_err); 555 556 return -ECONNRESET; 557 } 558 559 static struct ldc_version *find_by_major(u16 major) 560 { 561 struct ldc_version *ret = NULL; 562 int i; 563 564 for (i = 0; i < ARRAY_SIZE(ver_arr); i++) { 565 struct ldc_version *v = &ver_arr[i]; 566 if (v->major <= major) { 567 ret = v; 568 break; 569 } 570 } 571 return ret; 572 } 573 574 static int process_ver_info(struct ldc_channel *lp, struct ldc_version *vp) 575 { 576 struct ldc_version *vap; 577 int err; 578 579 ldcdbg(HS, "GOT VERSION INFO major[%x] minor[%x]\n", 580 vp->major, vp->minor); 581 582 if (lp->hs_state == LDC_HS_GOTVERS) { 583 lp->hs_state = LDC_HS_OPEN; 584 memset(&lp->ver, 0, sizeof(lp->ver)); 585 } 586 587 vap = find_by_major(vp->major); 588 if (!vap) { 589 err = send_version_nack(lp, 0, 0); 590 } else if (vap->major != vp->major) { 591 err = send_version_nack(lp, vap->major, vap->minor); 592 } else { 593 struct ldc_version ver = *vp; 594 if (ver.minor > vap->minor) 595 ver.minor = vap->minor; 596 err = send_version_ack(lp, &ver); 597 if (!err) { 598 lp->ver = ver; 599 lp->hs_state = LDC_HS_GOTVERS; 600 } 601 } 602 if (err) 603 return ldc_abort(lp); 604 605 return 0; 606 } 607 608 static int process_ver_ack(struct ldc_channel *lp, struct ldc_version *vp) 609 { 610 ldcdbg(HS, "GOT VERSION ACK major[%x] minor[%x]\n", 611 vp->major, vp->minor); 612 613 if (lp->hs_state == LDC_HS_GOTVERS) { 614 if (lp->ver.major != vp->major || 615 lp->ver.minor != vp->minor) 616 return ldc_abort(lp); 617 } else { 618 lp->ver = *vp; 619 lp->hs_state = LDC_HS_GOTVERS; 620 } 621 if (send_rts(lp)) 622 return ldc_abort(lp); 623 return 0; 624 } 625 626 static int process_ver_nack(struct ldc_channel *lp, struct ldc_version *vp) 627 { 628 struct ldc_version *vap; 629 struct ldc_packet *p; 630 unsigned long new_tail; 631 632 if (vp->major == 0 && vp->minor == 0) 633 return ldc_abort(lp); 634 635 vap = find_by_major(vp->major); 636 if (!vap) 637 return ldc_abort(lp); 638 639 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS, 640 vap, sizeof(*vap), 641 &new_tail); 642 if (!p) 643 return ldc_abort(lp); 644 645 return send_tx_packet(lp, p, new_tail); 646 } 647 648 static int process_version(struct ldc_channel *lp, 649 struct ldc_packet *p) 650 { 651 struct ldc_version *vp; 652 653 vp = (struct ldc_version *) p->u.u_data; 654 655 switch (p->stype) { 656 case LDC_INFO: 657 return process_ver_info(lp, vp); 658 659 case LDC_ACK: 660 return process_ver_ack(lp, vp); 661 662 case LDC_NACK: 663 return process_ver_nack(lp, vp); 664 665 default: 666 return ldc_abort(lp); 667 } 668 } 669 670 static int process_rts(struct ldc_channel *lp, 671 struct ldc_packet *p) 672 { 673 ldcdbg(HS, "GOT RTS stype[%x] seqid[%x] env[%x]\n", 674 p->stype, p->seqid, p->env); 675 676 if (p->stype != LDC_INFO || 677 lp->hs_state != LDC_HS_GOTVERS || 678 p->env != lp->cfg.mode) 679 return ldc_abort(lp); 680 681 lp->snd_nxt = p->seqid; 682 lp->rcv_nxt = p->seqid; 683 lp->hs_state = LDC_HS_SENTRTR; 684 if (send_rtr(lp)) 685 return ldc_abort(lp); 686 687 return 0; 688 } 689 690 static int process_rtr(struct ldc_channel *lp, 691 struct ldc_packet *p) 692 { 693 ldcdbg(HS, "GOT RTR stype[%x] seqid[%x] env[%x]\n", 694 p->stype, p->seqid, p->env); 695 696 if (p->stype != LDC_INFO || 697 p->env != lp->cfg.mode) 698 return ldc_abort(lp); 699 700 lp->snd_nxt = p->seqid; 701 lp->hs_state = LDC_HS_COMPLETE; 702 ldc_set_state(lp, LDC_STATE_CONNECTED); 703 send_rdx(lp); 704 705 return LDC_EVENT_UP; 706 } 707 708 static int rx_seq_ok(struct ldc_channel *lp, u32 seqid) 709 { 710 return lp->rcv_nxt + 1 == seqid; 711 } 712 713 static int process_rdx(struct ldc_channel *lp, 714 struct ldc_packet *p) 715 { 716 ldcdbg(HS, "GOT RDX stype[%x] seqid[%x] env[%x] ackid[%x]\n", 717 p->stype, p->seqid, p->env, p->u.r.ackid); 718 719 if (p->stype != LDC_INFO || 720 !(rx_seq_ok(lp, p->seqid))) 721 return ldc_abort(lp); 722 723 lp->rcv_nxt = p->seqid; 724 725 lp->hs_state = LDC_HS_COMPLETE; 726 ldc_set_state(lp, LDC_STATE_CONNECTED); 727 728 return LDC_EVENT_UP; 729 } 730 731 static int process_control_frame(struct ldc_channel *lp, 732 struct ldc_packet *p) 733 { 734 switch (p->ctrl) { 735 case LDC_VERS: 736 return process_version(lp, p); 737 738 case LDC_RTS: 739 return process_rts(lp, p); 740 741 case LDC_RTR: 742 return process_rtr(lp, p); 743 744 case LDC_RDX: 745 return process_rdx(lp, p); 746 747 default: 748 return ldc_abort(lp); 749 } 750 } 751 752 static int process_error_frame(struct ldc_channel *lp, 753 struct ldc_packet *p) 754 { 755 return ldc_abort(lp); 756 } 757 758 static int process_data_ack(struct ldc_channel *lp, 759 struct ldc_packet *ack) 760 { 761 unsigned long head = lp->tx_acked; 762 u32 ackid = ack->u.r.ackid; 763 764 while (1) { 765 struct ldc_packet *p = lp->tx_base + (head / LDC_PACKET_SIZE); 766 767 head = tx_advance(lp, head); 768 769 if (p->seqid == ackid) { 770 lp->tx_acked = head; 771 return 0; 772 } 773 if (head == lp->tx_tail) 774 return ldc_abort(lp); 775 } 776 777 return 0; 778 } 779 780 static void send_events(struct ldc_channel *lp, unsigned int event_mask) 781 { 782 if (event_mask & LDC_EVENT_RESET) 783 lp->cfg.event(lp->event_arg, LDC_EVENT_RESET); 784 if (event_mask & LDC_EVENT_UP) 785 lp->cfg.event(lp->event_arg, LDC_EVENT_UP); 786 if (event_mask & LDC_EVENT_DATA_READY) 787 lp->cfg.event(lp->event_arg, LDC_EVENT_DATA_READY); 788 } 789 790 static irqreturn_t ldc_rx(int irq, void *dev_id) 791 { 792 struct ldc_channel *lp = dev_id; 793 unsigned long orig_state, flags; 794 unsigned int event_mask; 795 796 spin_lock_irqsave(&lp->lock, flags); 797 798 orig_state = lp->chan_state; 799 800 /* We should probably check for hypervisor errors here and 801 * reset the LDC channel if we get one. 802 */ 803 sun4v_ldc_rx_get_state(lp->id, 804 &lp->rx_head, 805 &lp->rx_tail, 806 &lp->chan_state); 807 808 ldcdbg(RX, "RX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n", 809 orig_state, lp->chan_state, lp->rx_head, lp->rx_tail); 810 811 event_mask = 0; 812 813 if (lp->cfg.mode == LDC_MODE_RAW && 814 lp->chan_state == LDC_CHANNEL_UP) { 815 lp->hs_state = LDC_HS_COMPLETE; 816 ldc_set_state(lp, LDC_STATE_CONNECTED); 817 818 event_mask |= LDC_EVENT_UP; 819 820 orig_state = lp->chan_state; 821 } 822 823 /* If we are in reset state, flush the RX queue and ignore 824 * everything. 825 */ 826 if (lp->flags & LDC_FLAG_RESET) { 827 (void) __set_rx_head(lp, lp->rx_tail); 828 goto out; 829 } 830 831 /* Once we finish the handshake, we let the ldc_read() 832 * paths do all of the control frame and state management. 833 * Just trigger the callback. 834 */ 835 if (lp->hs_state == LDC_HS_COMPLETE) { 836 handshake_complete: 837 if (lp->chan_state != orig_state) { 838 unsigned int event = LDC_EVENT_RESET; 839 840 if (lp->chan_state == LDC_CHANNEL_UP) 841 event = LDC_EVENT_UP; 842 843 event_mask |= event; 844 } 845 if (lp->rx_head != lp->rx_tail) 846 event_mask |= LDC_EVENT_DATA_READY; 847 848 goto out; 849 } 850 851 if (lp->chan_state != orig_state) 852 goto out; 853 854 while (lp->rx_head != lp->rx_tail) { 855 struct ldc_packet *p; 856 unsigned long new; 857 int err; 858 859 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE); 860 861 switch (p->type) { 862 case LDC_CTRL: 863 err = process_control_frame(lp, p); 864 if (err > 0) 865 event_mask |= err; 866 break; 867 868 case LDC_DATA: 869 event_mask |= LDC_EVENT_DATA_READY; 870 err = 0; 871 break; 872 873 case LDC_ERR: 874 err = process_error_frame(lp, p); 875 break; 876 877 default: 878 err = ldc_abort(lp); 879 break; 880 } 881 882 if (err < 0) 883 break; 884 885 new = lp->rx_head; 886 new += LDC_PACKET_SIZE; 887 if (new == (lp->rx_num_entries * LDC_PACKET_SIZE)) 888 new = 0; 889 lp->rx_head = new; 890 891 err = __set_rx_head(lp, new); 892 if (err < 0) { 893 (void) ldc_abort(lp); 894 break; 895 } 896 if (lp->hs_state == LDC_HS_COMPLETE) 897 goto handshake_complete; 898 } 899 900 out: 901 spin_unlock_irqrestore(&lp->lock, flags); 902 903 send_events(lp, event_mask); 904 905 return IRQ_HANDLED; 906 } 907 908 static irqreturn_t ldc_tx(int irq, void *dev_id) 909 { 910 struct ldc_channel *lp = dev_id; 911 unsigned long flags, orig_state; 912 unsigned int event_mask = 0; 913 914 spin_lock_irqsave(&lp->lock, flags); 915 916 orig_state = lp->chan_state; 917 918 /* We should probably check for hypervisor errors here and 919 * reset the LDC channel if we get one. 920 */ 921 sun4v_ldc_tx_get_state(lp->id, 922 &lp->tx_head, 923 &lp->tx_tail, 924 &lp->chan_state); 925 926 ldcdbg(TX, " TX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n", 927 orig_state, lp->chan_state, lp->tx_head, lp->tx_tail); 928 929 if (lp->cfg.mode == LDC_MODE_RAW && 930 lp->chan_state == LDC_CHANNEL_UP) { 931 lp->hs_state = LDC_HS_COMPLETE; 932 ldc_set_state(lp, LDC_STATE_CONNECTED); 933 934 event_mask |= LDC_EVENT_UP; 935 } 936 937 spin_unlock_irqrestore(&lp->lock, flags); 938 939 send_events(lp, event_mask); 940 941 return IRQ_HANDLED; 942 } 943 944 /* XXX ldc_alloc() and ldc_free() needs to run under a mutex so 945 * XXX that addition and removal from the ldc_channel_list has 946 * XXX atomicity, otherwise the __ldc_channel_exists() check is 947 * XXX totally pointless as another thread can slip into ldc_alloc() 948 * XXX and add a channel with the same ID. There also needs to be 949 * XXX a spinlock for ldc_channel_list. 950 */ 951 static HLIST_HEAD(ldc_channel_list); 952 953 static int __ldc_channel_exists(unsigned long id) 954 { 955 struct ldc_channel *lp; 956 957 hlist_for_each_entry(lp, &ldc_channel_list, list) { 958 if (lp->id == id) 959 return 1; 960 } 961 return 0; 962 } 963 964 static int alloc_queue(const char *name, unsigned long num_entries, 965 struct ldc_packet **base, unsigned long *ra) 966 { 967 unsigned long size, order; 968 void *q; 969 970 size = num_entries * LDC_PACKET_SIZE; 971 order = get_order(size); 972 973 q = (void *) __get_free_pages(GFP_KERNEL, order); 974 if (!q) { 975 printk(KERN_ERR PFX "Alloc of %s queue failed with " 976 "size=%lu order=%lu\n", name, size, order); 977 return -ENOMEM; 978 } 979 980 memset(q, 0, PAGE_SIZE << order); 981 982 *base = q; 983 *ra = __pa(q); 984 985 return 0; 986 } 987 988 static void free_queue(unsigned long num_entries, struct ldc_packet *q) 989 { 990 unsigned long size, order; 991 992 if (!q) 993 return; 994 995 size = num_entries * LDC_PACKET_SIZE; 996 order = get_order(size); 997 998 free_pages((unsigned long)q, order); 999 } 1000 1001 /* XXX Make this configurable... XXX */ 1002 #define LDC_IOTABLE_SIZE (8 * 1024) 1003 1004 static int ldc_iommu_init(struct ldc_channel *lp) 1005 { 1006 unsigned long sz, num_tsb_entries, tsbsize, order; 1007 struct ldc_iommu *iommu = &lp->iommu; 1008 struct ldc_mtable_entry *table; 1009 unsigned long hv_err; 1010 int err; 1011 1012 num_tsb_entries = LDC_IOTABLE_SIZE; 1013 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry); 1014 1015 spin_lock_init(&iommu->lock); 1016 1017 sz = num_tsb_entries / 8; 1018 sz = (sz + 7UL) & ~7UL; 1019 iommu->arena.map = kzalloc(sz, GFP_KERNEL); 1020 if (!iommu->arena.map) { 1021 printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz); 1022 return -ENOMEM; 1023 } 1024 1025 iommu->arena.limit = num_tsb_entries; 1026 1027 order = get_order(tsbsize); 1028 1029 table = (struct ldc_mtable_entry *) 1030 __get_free_pages(GFP_KERNEL, order); 1031 err = -ENOMEM; 1032 if (!table) { 1033 printk(KERN_ERR PFX "Alloc of MTE table failed, " 1034 "size=%lu order=%lu\n", tsbsize, order); 1035 goto out_free_map; 1036 } 1037 1038 memset(table, 0, PAGE_SIZE << order); 1039 1040 iommu->page_table = table; 1041 1042 hv_err = sun4v_ldc_set_map_table(lp->id, __pa(table), 1043 num_tsb_entries); 1044 err = -EINVAL; 1045 if (hv_err) 1046 goto out_free_table; 1047 1048 return 0; 1049 1050 out_free_table: 1051 free_pages((unsigned long) table, order); 1052 iommu->page_table = NULL; 1053 1054 out_free_map: 1055 kfree(iommu->arena.map); 1056 iommu->arena.map = NULL; 1057 1058 return err; 1059 } 1060 1061 static void ldc_iommu_release(struct ldc_channel *lp) 1062 { 1063 struct ldc_iommu *iommu = &lp->iommu; 1064 unsigned long num_tsb_entries, tsbsize, order; 1065 1066 (void) sun4v_ldc_set_map_table(lp->id, 0, 0); 1067 1068 num_tsb_entries = iommu->arena.limit; 1069 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry); 1070 order = get_order(tsbsize); 1071 1072 free_pages((unsigned long) iommu->page_table, order); 1073 iommu->page_table = NULL; 1074 1075 kfree(iommu->arena.map); 1076 iommu->arena.map = NULL; 1077 } 1078 1079 struct ldc_channel *ldc_alloc(unsigned long id, 1080 const struct ldc_channel_config *cfgp, 1081 void *event_arg) 1082 { 1083 struct ldc_channel *lp; 1084 const struct ldc_mode_ops *mops; 1085 unsigned long dummy1, dummy2, hv_err; 1086 u8 mss, *mssbuf; 1087 int err; 1088 1089 err = -ENODEV; 1090 if (!ldom_domaining_enabled) 1091 goto out_err; 1092 1093 err = -EINVAL; 1094 if (!cfgp) 1095 goto out_err; 1096 1097 switch (cfgp->mode) { 1098 case LDC_MODE_RAW: 1099 mops = &raw_ops; 1100 mss = LDC_PACKET_SIZE; 1101 break; 1102 1103 case LDC_MODE_UNRELIABLE: 1104 mops = &nonraw_ops; 1105 mss = LDC_PACKET_SIZE - 8; 1106 break; 1107 1108 case LDC_MODE_STREAM: 1109 mops = &stream_ops; 1110 mss = LDC_PACKET_SIZE - 8 - 8; 1111 break; 1112 1113 default: 1114 goto out_err; 1115 } 1116 1117 if (!cfgp->event || !event_arg || !cfgp->rx_irq || !cfgp->tx_irq) 1118 goto out_err; 1119 1120 hv_err = sun4v_ldc_tx_qinfo(id, &dummy1, &dummy2); 1121 err = -ENODEV; 1122 if (hv_err == HV_ECHANNEL) 1123 goto out_err; 1124 1125 err = -EEXIST; 1126 if (__ldc_channel_exists(id)) 1127 goto out_err; 1128 1129 mssbuf = NULL; 1130 1131 lp = kzalloc(sizeof(*lp), GFP_KERNEL); 1132 err = -ENOMEM; 1133 if (!lp) 1134 goto out_err; 1135 1136 spin_lock_init(&lp->lock); 1137 1138 lp->id = id; 1139 1140 err = ldc_iommu_init(lp); 1141 if (err) 1142 goto out_free_ldc; 1143 1144 lp->mops = mops; 1145 lp->mss = mss; 1146 1147 lp->cfg = *cfgp; 1148 if (!lp->cfg.mtu) 1149 lp->cfg.mtu = LDC_DEFAULT_MTU; 1150 1151 if (lp->cfg.mode == LDC_MODE_STREAM) { 1152 mssbuf = kzalloc(lp->cfg.mtu, GFP_KERNEL); 1153 if (!mssbuf) { 1154 err = -ENOMEM; 1155 goto out_free_iommu; 1156 } 1157 lp->mssbuf = mssbuf; 1158 } 1159 1160 lp->event_arg = event_arg; 1161 1162 /* XXX allow setting via ldc_channel_config to override defaults 1163 * XXX or use some formula based upon mtu 1164 */ 1165 lp->tx_num_entries = LDC_DEFAULT_NUM_ENTRIES; 1166 lp->rx_num_entries = LDC_DEFAULT_NUM_ENTRIES; 1167 1168 err = alloc_queue("TX", lp->tx_num_entries, 1169 &lp->tx_base, &lp->tx_ra); 1170 if (err) 1171 goto out_free_mssbuf; 1172 1173 err = alloc_queue("RX", lp->rx_num_entries, 1174 &lp->rx_base, &lp->rx_ra); 1175 if (err) 1176 goto out_free_txq; 1177 1178 lp->flags |= LDC_FLAG_ALLOCED_QUEUES; 1179 1180 lp->hs_state = LDC_HS_CLOSED; 1181 ldc_set_state(lp, LDC_STATE_INIT); 1182 1183 INIT_HLIST_NODE(&lp->list); 1184 hlist_add_head(&lp->list, &ldc_channel_list); 1185 1186 INIT_HLIST_HEAD(&lp->mh_list); 1187 1188 return lp; 1189 1190 out_free_txq: 1191 free_queue(lp->tx_num_entries, lp->tx_base); 1192 1193 out_free_mssbuf: 1194 kfree(mssbuf); 1195 1196 out_free_iommu: 1197 ldc_iommu_release(lp); 1198 1199 out_free_ldc: 1200 kfree(lp); 1201 1202 out_err: 1203 return ERR_PTR(err); 1204 } 1205 EXPORT_SYMBOL(ldc_alloc); 1206 1207 void ldc_free(struct ldc_channel *lp) 1208 { 1209 if (lp->flags & LDC_FLAG_REGISTERED_IRQS) { 1210 free_irq(lp->cfg.rx_irq, lp); 1211 free_irq(lp->cfg.tx_irq, lp); 1212 } 1213 1214 if (lp->flags & LDC_FLAG_REGISTERED_QUEUES) { 1215 sun4v_ldc_tx_qconf(lp->id, 0, 0); 1216 sun4v_ldc_rx_qconf(lp->id, 0, 0); 1217 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES; 1218 } 1219 if (lp->flags & LDC_FLAG_ALLOCED_QUEUES) { 1220 free_queue(lp->tx_num_entries, lp->tx_base); 1221 free_queue(lp->rx_num_entries, lp->rx_base); 1222 lp->flags &= ~LDC_FLAG_ALLOCED_QUEUES; 1223 } 1224 1225 hlist_del(&lp->list); 1226 1227 kfree(lp->mssbuf); 1228 1229 ldc_iommu_release(lp); 1230 1231 kfree(lp); 1232 } 1233 EXPORT_SYMBOL(ldc_free); 1234 1235 /* Bind the channel. This registers the LDC queues with 1236 * the hypervisor and puts the channel into a pseudo-listening 1237 * state. This does not initiate a handshake, ldc_connect() does 1238 * that. 1239 */ 1240 int ldc_bind(struct ldc_channel *lp, const char *name) 1241 { 1242 unsigned long hv_err, flags; 1243 int err = -EINVAL; 1244 1245 if (!name || 1246 (lp->state != LDC_STATE_INIT)) 1247 return -EINVAL; 1248 1249 snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name); 1250 snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name); 1251 1252 err = request_irq(lp->cfg.rx_irq, ldc_rx, 0, 1253 lp->rx_irq_name, lp); 1254 if (err) 1255 return err; 1256 1257 err = request_irq(lp->cfg.tx_irq, ldc_tx, 0, 1258 lp->tx_irq_name, lp); 1259 if (err) { 1260 free_irq(lp->cfg.rx_irq, lp); 1261 return err; 1262 } 1263 1264 1265 spin_lock_irqsave(&lp->lock, flags); 1266 1267 enable_irq(lp->cfg.rx_irq); 1268 enable_irq(lp->cfg.tx_irq); 1269 1270 lp->flags |= LDC_FLAG_REGISTERED_IRQS; 1271 1272 err = -ENODEV; 1273 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0); 1274 if (hv_err) 1275 goto out_free_irqs; 1276 1277 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries); 1278 if (hv_err) 1279 goto out_free_irqs; 1280 1281 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0); 1282 if (hv_err) 1283 goto out_unmap_tx; 1284 1285 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries); 1286 if (hv_err) 1287 goto out_unmap_tx; 1288 1289 lp->flags |= LDC_FLAG_REGISTERED_QUEUES; 1290 1291 hv_err = sun4v_ldc_tx_get_state(lp->id, 1292 &lp->tx_head, 1293 &lp->tx_tail, 1294 &lp->chan_state); 1295 err = -EBUSY; 1296 if (hv_err) 1297 goto out_unmap_rx; 1298 1299 lp->tx_acked = lp->tx_head; 1300 1301 lp->hs_state = LDC_HS_OPEN; 1302 ldc_set_state(lp, LDC_STATE_BOUND); 1303 1304 spin_unlock_irqrestore(&lp->lock, flags); 1305 1306 return 0; 1307 1308 out_unmap_rx: 1309 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES; 1310 sun4v_ldc_rx_qconf(lp->id, 0, 0); 1311 1312 out_unmap_tx: 1313 sun4v_ldc_tx_qconf(lp->id, 0, 0); 1314 1315 out_free_irqs: 1316 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS; 1317 free_irq(lp->cfg.tx_irq, lp); 1318 free_irq(lp->cfg.rx_irq, lp); 1319 1320 spin_unlock_irqrestore(&lp->lock, flags); 1321 1322 return err; 1323 } 1324 EXPORT_SYMBOL(ldc_bind); 1325 1326 int ldc_connect(struct ldc_channel *lp) 1327 { 1328 unsigned long flags; 1329 int err; 1330 1331 if (lp->cfg.mode == LDC_MODE_RAW) 1332 return -EINVAL; 1333 1334 spin_lock_irqsave(&lp->lock, flags); 1335 1336 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) || 1337 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES) || 1338 lp->hs_state != LDC_HS_OPEN) 1339 err = ((lp->hs_state > LDC_HS_OPEN) ? 0 : -EINVAL); 1340 else 1341 err = start_handshake(lp); 1342 1343 spin_unlock_irqrestore(&lp->lock, flags); 1344 1345 return err; 1346 } 1347 EXPORT_SYMBOL(ldc_connect); 1348 1349 int ldc_disconnect(struct ldc_channel *lp) 1350 { 1351 unsigned long hv_err, flags; 1352 int err; 1353 1354 if (lp->cfg.mode == LDC_MODE_RAW) 1355 return -EINVAL; 1356 1357 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) || 1358 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES)) 1359 return -EINVAL; 1360 1361 spin_lock_irqsave(&lp->lock, flags); 1362 1363 err = -ENODEV; 1364 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0); 1365 if (hv_err) 1366 goto out_err; 1367 1368 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries); 1369 if (hv_err) 1370 goto out_err; 1371 1372 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0); 1373 if (hv_err) 1374 goto out_err; 1375 1376 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries); 1377 if (hv_err) 1378 goto out_err; 1379 1380 ldc_set_state(lp, LDC_STATE_BOUND); 1381 lp->hs_state = LDC_HS_OPEN; 1382 lp->flags |= LDC_FLAG_RESET; 1383 1384 spin_unlock_irqrestore(&lp->lock, flags); 1385 1386 return 0; 1387 1388 out_err: 1389 sun4v_ldc_tx_qconf(lp->id, 0, 0); 1390 sun4v_ldc_rx_qconf(lp->id, 0, 0); 1391 free_irq(lp->cfg.tx_irq, lp); 1392 free_irq(lp->cfg.rx_irq, lp); 1393 lp->flags &= ~(LDC_FLAG_REGISTERED_IRQS | 1394 LDC_FLAG_REGISTERED_QUEUES); 1395 ldc_set_state(lp, LDC_STATE_INIT); 1396 1397 spin_unlock_irqrestore(&lp->lock, flags); 1398 1399 return err; 1400 } 1401 EXPORT_SYMBOL(ldc_disconnect); 1402 1403 int ldc_state(struct ldc_channel *lp) 1404 { 1405 return lp->state; 1406 } 1407 EXPORT_SYMBOL(ldc_state); 1408 1409 static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size) 1410 { 1411 struct ldc_packet *p; 1412 unsigned long new_tail; 1413 int err; 1414 1415 if (size > LDC_PACKET_SIZE) 1416 return -EMSGSIZE; 1417 1418 p = data_get_tx_packet(lp, &new_tail); 1419 if (!p) 1420 return -EAGAIN; 1421 1422 memcpy(p, buf, size); 1423 1424 err = send_tx_packet(lp, p, new_tail); 1425 if (!err) 1426 err = size; 1427 1428 return err; 1429 } 1430 1431 static int read_raw(struct ldc_channel *lp, void *buf, unsigned int size) 1432 { 1433 struct ldc_packet *p; 1434 unsigned long hv_err, new; 1435 int err; 1436 1437 if (size < LDC_PACKET_SIZE) 1438 return -EINVAL; 1439 1440 hv_err = sun4v_ldc_rx_get_state(lp->id, 1441 &lp->rx_head, 1442 &lp->rx_tail, 1443 &lp->chan_state); 1444 if (hv_err) 1445 return ldc_abort(lp); 1446 1447 if (lp->chan_state == LDC_CHANNEL_DOWN || 1448 lp->chan_state == LDC_CHANNEL_RESETTING) 1449 return -ECONNRESET; 1450 1451 if (lp->rx_head == lp->rx_tail) 1452 return 0; 1453 1454 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE); 1455 memcpy(buf, p, LDC_PACKET_SIZE); 1456 1457 new = rx_advance(lp, lp->rx_head); 1458 lp->rx_head = new; 1459 1460 err = __set_rx_head(lp, new); 1461 if (err < 0) 1462 err = -ECONNRESET; 1463 else 1464 err = LDC_PACKET_SIZE; 1465 1466 return err; 1467 } 1468 1469 static const struct ldc_mode_ops raw_ops = { 1470 .write = write_raw, 1471 .read = read_raw, 1472 }; 1473 1474 static int write_nonraw(struct ldc_channel *lp, const void *buf, 1475 unsigned int size) 1476 { 1477 unsigned long hv_err, tail; 1478 unsigned int copied; 1479 u32 seq; 1480 int err; 1481 1482 hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail, 1483 &lp->chan_state); 1484 if (unlikely(hv_err)) 1485 return -EBUSY; 1486 1487 if (unlikely(lp->chan_state != LDC_CHANNEL_UP)) 1488 return ldc_abort(lp); 1489 1490 if (!tx_has_space_for(lp, size)) 1491 return -EAGAIN; 1492 1493 seq = lp->snd_nxt; 1494 copied = 0; 1495 tail = lp->tx_tail; 1496 while (copied < size) { 1497 struct ldc_packet *p = lp->tx_base + (tail / LDC_PACKET_SIZE); 1498 u8 *data = ((lp->cfg.mode == LDC_MODE_UNRELIABLE) ? 1499 p->u.u_data : 1500 p->u.r.r_data); 1501 int data_len; 1502 1503 p->type = LDC_DATA; 1504 p->stype = LDC_INFO; 1505 p->ctrl = 0; 1506 1507 data_len = size - copied; 1508 if (data_len > lp->mss) 1509 data_len = lp->mss; 1510 1511 BUG_ON(data_len > LDC_LEN); 1512 1513 p->env = (data_len | 1514 (copied == 0 ? LDC_START : 0) | 1515 (data_len == size - copied ? LDC_STOP : 0)); 1516 1517 p->seqid = ++seq; 1518 1519 ldcdbg(DATA, "SENT DATA [%02x:%02x:%02x:%02x:%08x]\n", 1520 p->type, 1521 p->stype, 1522 p->ctrl, 1523 p->env, 1524 p->seqid); 1525 1526 memcpy(data, buf, data_len); 1527 buf += data_len; 1528 copied += data_len; 1529 1530 tail = tx_advance(lp, tail); 1531 } 1532 1533 err = set_tx_tail(lp, tail); 1534 if (!err) { 1535 lp->snd_nxt = seq; 1536 err = size; 1537 } 1538 1539 return err; 1540 } 1541 1542 static int rx_bad_seq(struct ldc_channel *lp, struct ldc_packet *p, 1543 struct ldc_packet *first_frag) 1544 { 1545 int err; 1546 1547 if (first_frag) 1548 lp->rcv_nxt = first_frag->seqid - 1; 1549 1550 err = send_data_nack(lp, p); 1551 if (err) 1552 return err; 1553 1554 err = __set_rx_head(lp, lp->rx_tail); 1555 if (err < 0) 1556 return ldc_abort(lp); 1557 1558 return 0; 1559 } 1560 1561 static int data_ack_nack(struct ldc_channel *lp, struct ldc_packet *p) 1562 { 1563 if (p->stype & LDC_ACK) { 1564 int err = process_data_ack(lp, p); 1565 if (err) 1566 return err; 1567 } 1568 if (p->stype & LDC_NACK) 1569 return ldc_abort(lp); 1570 1571 return 0; 1572 } 1573 1574 static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head) 1575 { 1576 unsigned long dummy; 1577 int limit = 1000; 1578 1579 ldcdbg(DATA, "DATA WAIT cur_head[%lx] rx_head[%lx] rx_tail[%lx]\n", 1580 cur_head, lp->rx_head, lp->rx_tail); 1581 while (limit-- > 0) { 1582 unsigned long hv_err; 1583 1584 hv_err = sun4v_ldc_rx_get_state(lp->id, 1585 &dummy, 1586 &lp->rx_tail, 1587 &lp->chan_state); 1588 if (hv_err) 1589 return ldc_abort(lp); 1590 1591 if (lp->chan_state == LDC_CHANNEL_DOWN || 1592 lp->chan_state == LDC_CHANNEL_RESETTING) 1593 return -ECONNRESET; 1594 1595 if (cur_head != lp->rx_tail) { 1596 ldcdbg(DATA, "DATA WAIT DONE " 1597 "head[%lx] tail[%lx] chan_state[%lx]\n", 1598 dummy, lp->rx_tail, lp->chan_state); 1599 return 0; 1600 } 1601 1602 udelay(1); 1603 } 1604 return -EAGAIN; 1605 } 1606 1607 static int rx_set_head(struct ldc_channel *lp, unsigned long head) 1608 { 1609 int err = __set_rx_head(lp, head); 1610 1611 if (err < 0) 1612 return ldc_abort(lp); 1613 1614 lp->rx_head = head; 1615 return 0; 1616 } 1617 1618 static void send_data_ack(struct ldc_channel *lp) 1619 { 1620 unsigned long new_tail; 1621 struct ldc_packet *p; 1622 1623 p = data_get_tx_packet(lp, &new_tail); 1624 if (likely(p)) { 1625 int err; 1626 1627 memset(p, 0, sizeof(*p)); 1628 p->type = LDC_DATA; 1629 p->stype = LDC_ACK; 1630 p->ctrl = 0; 1631 p->seqid = lp->snd_nxt + 1; 1632 p->u.r.ackid = lp->rcv_nxt; 1633 1634 err = send_tx_packet(lp, p, new_tail); 1635 if (!err) 1636 lp->snd_nxt++; 1637 } 1638 } 1639 1640 static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size) 1641 { 1642 struct ldc_packet *first_frag; 1643 unsigned long hv_err, new; 1644 int err, copied; 1645 1646 hv_err = sun4v_ldc_rx_get_state(lp->id, 1647 &lp->rx_head, 1648 &lp->rx_tail, 1649 &lp->chan_state); 1650 if (hv_err) 1651 return ldc_abort(lp); 1652 1653 if (lp->chan_state == LDC_CHANNEL_DOWN || 1654 lp->chan_state == LDC_CHANNEL_RESETTING) 1655 return -ECONNRESET; 1656 1657 if (lp->rx_head == lp->rx_tail) 1658 return 0; 1659 1660 first_frag = NULL; 1661 copied = err = 0; 1662 new = lp->rx_head; 1663 while (1) { 1664 struct ldc_packet *p; 1665 int pkt_len; 1666 1667 BUG_ON(new == lp->rx_tail); 1668 p = lp->rx_base + (new / LDC_PACKET_SIZE); 1669 1670 ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x:%08x] " 1671 "rcv_nxt[%08x]\n", 1672 p->type, 1673 p->stype, 1674 p->ctrl, 1675 p->env, 1676 p->seqid, 1677 p->u.r.ackid, 1678 lp->rcv_nxt); 1679 1680 if (unlikely(!rx_seq_ok(lp, p->seqid))) { 1681 err = rx_bad_seq(lp, p, first_frag); 1682 copied = 0; 1683 break; 1684 } 1685 1686 if (p->type & LDC_CTRL) { 1687 err = process_control_frame(lp, p); 1688 if (err < 0) 1689 break; 1690 err = 0; 1691 } 1692 1693 lp->rcv_nxt = p->seqid; 1694 1695 if (!(p->type & LDC_DATA)) { 1696 new = rx_advance(lp, new); 1697 goto no_data; 1698 } 1699 if (p->stype & (LDC_ACK | LDC_NACK)) { 1700 err = data_ack_nack(lp, p); 1701 if (err) 1702 break; 1703 } 1704 if (!(p->stype & LDC_INFO)) { 1705 new = rx_advance(lp, new); 1706 err = rx_set_head(lp, new); 1707 if (err) 1708 break; 1709 goto no_data; 1710 } 1711 1712 pkt_len = p->env & LDC_LEN; 1713 1714 /* Every initial packet starts with the START bit set. 1715 * 1716 * Singleton packets will have both START+STOP set. 1717 * 1718 * Fragments will have START set in the first frame, STOP 1719 * set in the last frame, and neither bit set in middle 1720 * frames of the packet. 1721 * 1722 * Therefore if we are at the beginning of a packet and 1723 * we don't see START, or we are in the middle of a fragmented 1724 * packet and do see START, we are unsynchronized and should 1725 * flush the RX queue. 1726 */ 1727 if ((first_frag == NULL && !(p->env & LDC_START)) || 1728 (first_frag != NULL && (p->env & LDC_START))) { 1729 if (!first_frag) 1730 new = rx_advance(lp, new); 1731 1732 err = rx_set_head(lp, new); 1733 if (err) 1734 break; 1735 1736 if (!first_frag) 1737 goto no_data; 1738 } 1739 if (!first_frag) 1740 first_frag = p; 1741 1742 if (pkt_len > size - copied) { 1743 /* User didn't give us a big enough buffer, 1744 * what to do? This is a pretty serious error. 1745 * 1746 * Since we haven't updated the RX ring head to 1747 * consume any of the packets, signal the error 1748 * to the user and just leave the RX ring alone. 1749 * 1750 * This seems the best behavior because this allows 1751 * a user of the LDC layer to start with a small 1752 * RX buffer for ldc_read() calls and use -EMSGSIZE 1753 * as a cue to enlarge it's read buffer. 1754 */ 1755 err = -EMSGSIZE; 1756 break; 1757 } 1758 1759 /* Ok, we are gonna eat this one. */ 1760 new = rx_advance(lp, new); 1761 1762 memcpy(buf, 1763 (lp->cfg.mode == LDC_MODE_UNRELIABLE ? 1764 p->u.u_data : p->u.r.r_data), pkt_len); 1765 buf += pkt_len; 1766 copied += pkt_len; 1767 1768 if (p->env & LDC_STOP) 1769 break; 1770 1771 no_data: 1772 if (new == lp->rx_tail) { 1773 err = rx_data_wait(lp, new); 1774 if (err) 1775 break; 1776 } 1777 } 1778 1779 if (!err) 1780 err = rx_set_head(lp, new); 1781 1782 if (err && first_frag) 1783 lp->rcv_nxt = first_frag->seqid - 1; 1784 1785 if (!err) { 1786 err = copied; 1787 if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE) 1788 send_data_ack(lp); 1789 } 1790 1791 return err; 1792 } 1793 1794 static const struct ldc_mode_ops nonraw_ops = { 1795 .write = write_nonraw, 1796 .read = read_nonraw, 1797 }; 1798 1799 static int write_stream(struct ldc_channel *lp, const void *buf, 1800 unsigned int size) 1801 { 1802 if (size > lp->cfg.mtu) 1803 size = lp->cfg.mtu; 1804 return write_nonraw(lp, buf, size); 1805 } 1806 1807 static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size) 1808 { 1809 if (!lp->mssbuf_len) { 1810 int err = read_nonraw(lp, lp->mssbuf, lp->cfg.mtu); 1811 if (err < 0) 1812 return err; 1813 1814 lp->mssbuf_len = err; 1815 lp->mssbuf_off = 0; 1816 } 1817 1818 if (size > lp->mssbuf_len) 1819 size = lp->mssbuf_len; 1820 memcpy(buf, lp->mssbuf + lp->mssbuf_off, size); 1821 1822 lp->mssbuf_off += size; 1823 lp->mssbuf_len -= size; 1824 1825 return size; 1826 } 1827 1828 static const struct ldc_mode_ops stream_ops = { 1829 .write = write_stream, 1830 .read = read_stream, 1831 }; 1832 1833 int ldc_write(struct ldc_channel *lp, const void *buf, unsigned int size) 1834 { 1835 unsigned long flags; 1836 int err; 1837 1838 if (!buf) 1839 return -EINVAL; 1840 1841 if (!size) 1842 return 0; 1843 1844 spin_lock_irqsave(&lp->lock, flags); 1845 1846 if (lp->hs_state != LDC_HS_COMPLETE) 1847 err = -ENOTCONN; 1848 else 1849 err = lp->mops->write(lp, buf, size); 1850 1851 spin_unlock_irqrestore(&lp->lock, flags); 1852 1853 return err; 1854 } 1855 EXPORT_SYMBOL(ldc_write); 1856 1857 int ldc_read(struct ldc_channel *lp, void *buf, unsigned int size) 1858 { 1859 unsigned long flags; 1860 int err; 1861 1862 if (!buf) 1863 return -EINVAL; 1864 1865 if (!size) 1866 return 0; 1867 1868 spin_lock_irqsave(&lp->lock, flags); 1869 1870 if (lp->hs_state != LDC_HS_COMPLETE) 1871 err = -ENOTCONN; 1872 else 1873 err = lp->mops->read(lp, buf, size); 1874 1875 spin_unlock_irqrestore(&lp->lock, flags); 1876 1877 return err; 1878 } 1879 EXPORT_SYMBOL(ldc_read); 1880 1881 static long arena_alloc(struct ldc_iommu *iommu, unsigned long npages) 1882 { 1883 struct iommu_arena *arena = &iommu->arena; 1884 unsigned long n, start, end, limit; 1885 int pass; 1886 1887 limit = arena->limit; 1888 start = arena->hint; 1889 pass = 0; 1890 1891 again: 1892 n = bitmap_find_next_zero_area(arena->map, limit, start, npages, 0); 1893 end = n + npages; 1894 if (unlikely(end >= limit)) { 1895 if (likely(pass < 1)) { 1896 limit = start; 1897 start = 0; 1898 pass++; 1899 goto again; 1900 } else { 1901 /* Scanned the whole thing, give up. */ 1902 return -1; 1903 } 1904 } 1905 bitmap_set(arena->map, n, npages); 1906 1907 arena->hint = end; 1908 1909 return n; 1910 } 1911 1912 #define COOKIE_PGSZ_CODE 0xf000000000000000ULL 1913 #define COOKIE_PGSZ_CODE_SHIFT 60ULL 1914 1915 static u64 pagesize_code(void) 1916 { 1917 switch (PAGE_SIZE) { 1918 default: 1919 case (8ULL * 1024ULL): 1920 return 0; 1921 case (64ULL * 1024ULL): 1922 return 1; 1923 case (512ULL * 1024ULL): 1924 return 2; 1925 case (4ULL * 1024ULL * 1024ULL): 1926 return 3; 1927 case (32ULL * 1024ULL * 1024ULL): 1928 return 4; 1929 case (256ULL * 1024ULL * 1024ULL): 1930 return 5; 1931 } 1932 } 1933 1934 static u64 make_cookie(u64 index, u64 pgsz_code, u64 page_offset) 1935 { 1936 return ((pgsz_code << COOKIE_PGSZ_CODE_SHIFT) | 1937 (index << PAGE_SHIFT) | 1938 page_offset); 1939 } 1940 1941 static u64 cookie_to_index(u64 cookie, unsigned long *shift) 1942 { 1943 u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT; 1944 1945 cookie &= ~COOKIE_PGSZ_CODE; 1946 1947 *shift = szcode * 3; 1948 1949 return (cookie >> (13ULL + (szcode * 3ULL))); 1950 } 1951 1952 static struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu, 1953 unsigned long npages) 1954 { 1955 long entry; 1956 1957 entry = arena_alloc(iommu, npages); 1958 if (unlikely(entry < 0)) 1959 return NULL; 1960 1961 return iommu->page_table + entry; 1962 } 1963 1964 static u64 perm_to_mte(unsigned int map_perm) 1965 { 1966 u64 mte_base; 1967 1968 mte_base = pagesize_code(); 1969 1970 if (map_perm & LDC_MAP_SHADOW) { 1971 if (map_perm & LDC_MAP_R) 1972 mte_base |= LDC_MTE_COPY_R; 1973 if (map_perm & LDC_MAP_W) 1974 mte_base |= LDC_MTE_COPY_W; 1975 } 1976 if (map_perm & LDC_MAP_DIRECT) { 1977 if (map_perm & LDC_MAP_R) 1978 mte_base |= LDC_MTE_READ; 1979 if (map_perm & LDC_MAP_W) 1980 mte_base |= LDC_MTE_WRITE; 1981 if (map_perm & LDC_MAP_X) 1982 mte_base |= LDC_MTE_EXEC; 1983 } 1984 if (map_perm & LDC_MAP_IO) { 1985 if (map_perm & LDC_MAP_R) 1986 mte_base |= LDC_MTE_IOMMU_R; 1987 if (map_perm & LDC_MAP_W) 1988 mte_base |= LDC_MTE_IOMMU_W; 1989 } 1990 1991 return mte_base; 1992 } 1993 1994 static int pages_in_region(unsigned long base, long len) 1995 { 1996 int count = 0; 1997 1998 do { 1999 unsigned long new = (base + PAGE_SIZE) & PAGE_MASK; 2000 2001 len -= (new - base); 2002 base = new; 2003 count++; 2004 } while (len > 0); 2005 2006 return count; 2007 } 2008 2009 struct cookie_state { 2010 struct ldc_mtable_entry *page_table; 2011 struct ldc_trans_cookie *cookies; 2012 u64 mte_base; 2013 u64 prev_cookie; 2014 u32 pte_idx; 2015 u32 nc; 2016 }; 2017 2018 static void fill_cookies(struct cookie_state *sp, unsigned long pa, 2019 unsigned long off, unsigned long len) 2020 { 2021 do { 2022 unsigned long tlen, new = pa + PAGE_SIZE; 2023 u64 this_cookie; 2024 2025 sp->page_table[sp->pte_idx].mte = sp->mte_base | pa; 2026 2027 tlen = PAGE_SIZE; 2028 if (off) 2029 tlen = PAGE_SIZE - off; 2030 if (tlen > len) 2031 tlen = len; 2032 2033 this_cookie = make_cookie(sp->pte_idx, 2034 pagesize_code(), off); 2035 2036 off = 0; 2037 2038 if (this_cookie == sp->prev_cookie) { 2039 sp->cookies[sp->nc - 1].cookie_size += tlen; 2040 } else { 2041 sp->cookies[sp->nc].cookie_addr = this_cookie; 2042 sp->cookies[sp->nc].cookie_size = tlen; 2043 sp->nc++; 2044 } 2045 sp->prev_cookie = this_cookie + tlen; 2046 2047 sp->pte_idx++; 2048 2049 len -= tlen; 2050 pa = new; 2051 } while (len > 0); 2052 } 2053 2054 static int sg_count_one(struct scatterlist *sg) 2055 { 2056 unsigned long base = page_to_pfn(sg_page(sg)) << PAGE_SHIFT; 2057 long len = sg->length; 2058 2059 if ((sg->offset | len) & (8UL - 1)) 2060 return -EFAULT; 2061 2062 return pages_in_region(base + sg->offset, len); 2063 } 2064 2065 static int sg_count_pages(struct scatterlist *sg, int num_sg) 2066 { 2067 int count; 2068 int i; 2069 2070 count = 0; 2071 for (i = 0; i < num_sg; i++) { 2072 int err = sg_count_one(sg + i); 2073 if (err < 0) 2074 return err; 2075 count += err; 2076 } 2077 2078 return count; 2079 } 2080 2081 int ldc_map_sg(struct ldc_channel *lp, 2082 struct scatterlist *sg, int num_sg, 2083 struct ldc_trans_cookie *cookies, int ncookies, 2084 unsigned int map_perm) 2085 { 2086 unsigned long i, npages, flags; 2087 struct ldc_mtable_entry *base; 2088 struct cookie_state state; 2089 struct ldc_iommu *iommu; 2090 int err; 2091 2092 if (map_perm & ~LDC_MAP_ALL) 2093 return -EINVAL; 2094 2095 err = sg_count_pages(sg, num_sg); 2096 if (err < 0) 2097 return err; 2098 2099 npages = err; 2100 if (err > ncookies) 2101 return -EMSGSIZE; 2102 2103 iommu = &lp->iommu; 2104 2105 spin_lock_irqsave(&iommu->lock, flags); 2106 base = alloc_npages(iommu, npages); 2107 spin_unlock_irqrestore(&iommu->lock, flags); 2108 2109 if (!base) 2110 return -ENOMEM; 2111 2112 state.page_table = iommu->page_table; 2113 state.cookies = cookies; 2114 state.mte_base = perm_to_mte(map_perm); 2115 state.prev_cookie = ~(u64)0; 2116 state.pte_idx = (base - iommu->page_table); 2117 state.nc = 0; 2118 2119 for (i = 0; i < num_sg; i++) 2120 fill_cookies(&state, page_to_pfn(sg_page(&sg[i])) << PAGE_SHIFT, 2121 sg[i].offset, sg[i].length); 2122 2123 return state.nc; 2124 } 2125 EXPORT_SYMBOL(ldc_map_sg); 2126 2127 int ldc_map_single(struct ldc_channel *lp, 2128 void *buf, unsigned int len, 2129 struct ldc_trans_cookie *cookies, int ncookies, 2130 unsigned int map_perm) 2131 { 2132 unsigned long npages, pa, flags; 2133 struct ldc_mtable_entry *base; 2134 struct cookie_state state; 2135 struct ldc_iommu *iommu; 2136 2137 if ((map_perm & ~LDC_MAP_ALL) || (ncookies < 1)) 2138 return -EINVAL; 2139 2140 pa = __pa(buf); 2141 if ((pa | len) & (8UL - 1)) 2142 return -EFAULT; 2143 2144 npages = pages_in_region(pa, len); 2145 2146 iommu = &lp->iommu; 2147 2148 spin_lock_irqsave(&iommu->lock, flags); 2149 base = alloc_npages(iommu, npages); 2150 spin_unlock_irqrestore(&iommu->lock, flags); 2151 2152 if (!base) 2153 return -ENOMEM; 2154 2155 state.page_table = iommu->page_table; 2156 state.cookies = cookies; 2157 state.mte_base = perm_to_mte(map_perm); 2158 state.prev_cookie = ~(u64)0; 2159 state.pte_idx = (base - iommu->page_table); 2160 state.nc = 0; 2161 fill_cookies(&state, (pa & PAGE_MASK), (pa & ~PAGE_MASK), len); 2162 BUG_ON(state.nc > ncookies); 2163 2164 return state.nc; 2165 } 2166 EXPORT_SYMBOL(ldc_map_single); 2167 2168 static void free_npages(unsigned long id, struct ldc_iommu *iommu, 2169 u64 cookie, u64 size) 2170 { 2171 struct iommu_arena *arena = &iommu->arena; 2172 unsigned long i, shift, index, npages; 2173 struct ldc_mtable_entry *base; 2174 2175 npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT; 2176 index = cookie_to_index(cookie, &shift); 2177 base = iommu->page_table + index; 2178 2179 BUG_ON(index > arena->limit || 2180 (index + npages) > arena->limit); 2181 2182 for (i = 0; i < npages; i++) { 2183 if (base->cookie) 2184 sun4v_ldc_revoke(id, cookie + (i << shift), 2185 base->cookie); 2186 base->mte = 0; 2187 __clear_bit(index + i, arena->map); 2188 } 2189 } 2190 2191 void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies, 2192 int ncookies) 2193 { 2194 struct ldc_iommu *iommu = &lp->iommu; 2195 unsigned long flags; 2196 int i; 2197 2198 spin_lock_irqsave(&iommu->lock, flags); 2199 for (i = 0; i < ncookies; i++) { 2200 u64 addr = cookies[i].cookie_addr; 2201 u64 size = cookies[i].cookie_size; 2202 2203 free_npages(lp->id, iommu, addr, size); 2204 } 2205 spin_unlock_irqrestore(&iommu->lock, flags); 2206 } 2207 EXPORT_SYMBOL(ldc_unmap); 2208 2209 int ldc_copy(struct ldc_channel *lp, int copy_dir, 2210 void *buf, unsigned int len, unsigned long offset, 2211 struct ldc_trans_cookie *cookies, int ncookies) 2212 { 2213 unsigned int orig_len; 2214 unsigned long ra; 2215 int i; 2216 2217 if (copy_dir != LDC_COPY_IN && copy_dir != LDC_COPY_OUT) { 2218 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Bad copy_dir[%d]\n", 2219 lp->id, copy_dir); 2220 return -EINVAL; 2221 } 2222 2223 ra = __pa(buf); 2224 if ((ra | len | offset) & (8UL - 1)) { 2225 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Unaligned buffer " 2226 "ra[%lx] len[%x] offset[%lx]\n", 2227 lp->id, ra, len, offset); 2228 return -EFAULT; 2229 } 2230 2231 if (lp->hs_state != LDC_HS_COMPLETE || 2232 (lp->flags & LDC_FLAG_RESET)) { 2233 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Link down hs_state[%x] " 2234 "flags[%x]\n", lp->id, lp->hs_state, lp->flags); 2235 return -ECONNRESET; 2236 } 2237 2238 orig_len = len; 2239 for (i = 0; i < ncookies; i++) { 2240 unsigned long cookie_raddr = cookies[i].cookie_addr; 2241 unsigned long this_len = cookies[i].cookie_size; 2242 unsigned long actual_len; 2243 2244 if (unlikely(offset)) { 2245 unsigned long this_off = offset; 2246 2247 if (this_off > this_len) 2248 this_off = this_len; 2249 2250 offset -= this_off; 2251 this_len -= this_off; 2252 if (!this_len) 2253 continue; 2254 cookie_raddr += this_off; 2255 } 2256 2257 if (this_len > len) 2258 this_len = len; 2259 2260 while (1) { 2261 unsigned long hv_err; 2262 2263 hv_err = sun4v_ldc_copy(lp->id, copy_dir, 2264 cookie_raddr, ra, 2265 this_len, &actual_len); 2266 if (unlikely(hv_err)) { 2267 printk(KERN_ERR PFX "ldc_copy: ID[%lu] " 2268 "HV error %lu\n", 2269 lp->id, hv_err); 2270 if (lp->hs_state != LDC_HS_COMPLETE || 2271 (lp->flags & LDC_FLAG_RESET)) 2272 return -ECONNRESET; 2273 else 2274 return -EFAULT; 2275 } 2276 2277 cookie_raddr += actual_len; 2278 ra += actual_len; 2279 len -= actual_len; 2280 if (actual_len == this_len) 2281 break; 2282 2283 this_len -= actual_len; 2284 } 2285 2286 if (!len) 2287 break; 2288 } 2289 2290 /* It is caller policy what to do about short copies. 2291 * For example, a networking driver can declare the 2292 * packet a runt and drop it. 2293 */ 2294 2295 return orig_len - len; 2296 } 2297 EXPORT_SYMBOL(ldc_copy); 2298 2299 void *ldc_alloc_exp_dring(struct ldc_channel *lp, unsigned int len, 2300 struct ldc_trans_cookie *cookies, int *ncookies, 2301 unsigned int map_perm) 2302 { 2303 void *buf; 2304 int err; 2305 2306 if (len & (8UL - 1)) 2307 return ERR_PTR(-EINVAL); 2308 2309 buf = kzalloc(len, GFP_KERNEL); 2310 if (!buf) 2311 return ERR_PTR(-ENOMEM); 2312 2313 err = ldc_map_single(lp, buf, len, cookies, *ncookies, map_perm); 2314 if (err < 0) { 2315 kfree(buf); 2316 return ERR_PTR(err); 2317 } 2318 *ncookies = err; 2319 2320 return buf; 2321 } 2322 EXPORT_SYMBOL(ldc_alloc_exp_dring); 2323 2324 void ldc_free_exp_dring(struct ldc_channel *lp, void *buf, unsigned int len, 2325 struct ldc_trans_cookie *cookies, int ncookies) 2326 { 2327 ldc_unmap(lp, cookies, ncookies); 2328 kfree(buf); 2329 } 2330 EXPORT_SYMBOL(ldc_free_exp_dring); 2331 2332 static int __init ldc_init(void) 2333 { 2334 unsigned long major, minor; 2335 struct mdesc_handle *hp; 2336 const u64 *v; 2337 int err; 2338 u64 mp; 2339 2340 hp = mdesc_grab(); 2341 if (!hp) 2342 return -ENODEV; 2343 2344 mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform"); 2345 err = -ENODEV; 2346 if (mp == MDESC_NODE_NULL) 2347 goto out; 2348 2349 v = mdesc_get_property(hp, mp, "domaining-enabled", NULL); 2350 if (!v) 2351 goto out; 2352 2353 major = 1; 2354 minor = 0; 2355 if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) { 2356 printk(KERN_INFO PFX "Could not register LDOM hvapi.\n"); 2357 goto out; 2358 } 2359 2360 printk(KERN_INFO "%s", version); 2361 2362 if (!*v) { 2363 printk(KERN_INFO PFX "Domaining disabled.\n"); 2364 goto out; 2365 } 2366 ldom_domaining_enabled = 1; 2367 err = 0; 2368 2369 out: 2370 mdesc_release(hp); 2371 return err; 2372 } 2373 2374 core_initcall(ldc_init); 2375