arch/sparc/kernel/ldc.c

   1 /* ldc.c: Logical Domain Channel link-layer protocol driver.
   2  *
   3  * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/export.h>
   8 #include <linux/slab.h>
   9 #include <linux/spinlock.h>
  10 #include <linux/delay.h>
  11 #include <linux/errno.h>
  12 #include <linux/string.h>
  13 #include <linux/scatterlist.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/list.h>
  16 #include <linux/init.h>
  17 #include <linux/bitmap.h>
  18 #include <linux/iommu-common.h>
  19
  20 #include <asm/hypervisor.h>
  21 #include <asm/iommu.h>
  22 #include <asm/page.h>
  23 #include <asm/ldc.h>
  24 #include <asm/mdesc.h>
  25
  26 #define DRV_MODULE_NAME         "ldc"
  27 #define PFX DRV_MODULE_NAME     ": "
  28 #define DRV_MODULE_VERSION      "1.1"
  29 #define DRV_MODULE_RELDATE      "July 22, 2008"
  30
  31 #define COOKIE_PGSZ_CODE        0xf000000000000000ULL
  32 #define COOKIE_PGSZ_CODE_SHIFT  60ULL
  33
  34
  35 static char version[] =
  36         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
  37
  38 /* Packet header layout for unreliable and reliable mode frames.
  39  * When in RAW mode, packets are simply straight 64-byte payloads
  40  * with no headers.
  41  */
  42 struct ldc_packet {
  43         u8                      type;
  44 #define LDC_CTRL                0x01
  45 #define LDC_DATA                0x02
  46 #define LDC_ERR                 0x10
  47
  48         u8                      stype;
  49 #define LDC_INFO                0x01
  50 #define LDC_ACK                 0x02
  51 #define LDC_NACK                0x04
  52
  53         u8                      ctrl;
  54 #define LDC_VERS                0x01 /* Link Version            */
  55 #define LDC_RTS                 0x02 /* Request To Send         */
  56 #define LDC_RTR                 0x03 /* Ready To Receive        */
  57 #define LDC_RDX                 0x04 /* Ready for Data eXchange */
  58 #define LDC_CTRL_MSK            0x0f
  59
  60         u8                      env;
  61 #define LDC_LEN                 0x3f
  62 #define LDC_FRAG_MASK           0xc0
  63 #define LDC_START               0x40
  64 #define LDC_STOP                0x80
  65
  66         u32                     seqid;
  67
  68         union {
  69                 u8              u_data[LDC_PACKET_SIZE - 8];
  70                 struct {
  71                         u32     pad;
  72                         u32     ackid;
  73                         u8      r_data[LDC_PACKET_SIZE - 8 - 8];
  74                 } r;
  75         } u;
  76 };
  77
  78 struct ldc_version {
  79         u16 major;
  80         u16 minor;
  81 };
  82
  83 /* Ordered from largest major to lowest.  */
  84 static struct ldc_version ver_arr[] = {
  85         { .major = 1, .minor = 0 },
  86 };
  87
  88 #define LDC_DEFAULT_MTU                 (4 * LDC_PACKET_SIZE)
  89 #define LDC_DEFAULT_NUM_ENTRIES         (PAGE_SIZE / LDC_PACKET_SIZE)
  90
  91 struct ldc_channel;
  92
  93 struct ldc_mode_ops {
  94         int (*write)(struct ldc_channel *, const void *, unsigned int);
  95         int (*read)(struct ldc_channel *, void *, unsigned int);
  96 };
  97
  98 static const struct ldc_mode_ops raw_ops;
  99 static const struct ldc_mode_ops nonraw_ops;
 100 static const struct ldc_mode_ops stream_ops;
 101
 102 int ldom_domaining_enabled;
 103
 104 struct ldc_iommu {
 105         /* Protects ldc_unmap.  */
 106         spinlock_t                      lock;
 107         struct ldc_mtable_entry         *page_table;
 108         struct iommu_map_table          iommu_map_table;
 109 };
 110
 111 struct ldc_channel {
 112         /* Protects all operations that depend upon channel state.  */
 113         spinlock_t                      lock;
 114
 115         unsigned long                   id;
 116
 117         u8                              *mssbuf;
 118         u32                             mssbuf_len;
 119         u32                             mssbuf_off;
 120
 121         struct ldc_packet               *tx_base;
 122         unsigned long                   tx_head;
 123         unsigned long                   tx_tail;
 124         unsigned long                   tx_num_entries;
 125         unsigned long                   tx_ra;
 126
 127         unsigned long                   tx_acked;
 128
 129         struct ldc_packet               *rx_base;
 130         unsigned long                   rx_head;
 131         unsigned long                   rx_tail;
 132         unsigned long                   rx_num_entries;
 133         unsigned long                   rx_ra;
 134
 135         u32                             rcv_nxt;
 136         u32                             snd_nxt;
 137
 138         unsigned long                   chan_state;
 139
 140         struct ldc_channel_config       cfg;
 141         void                            *event_arg;
 142
 143         const struct ldc_mode_ops       *mops;
 144
 145         struct ldc_iommu                iommu;
 146
 147         struct ldc_version              ver;
 148
 149         u8                              hs_state;
 150 #define LDC_HS_CLOSED                   0x00
 151 #define LDC_HS_OPEN                     0x01
 152 #define LDC_HS_GOTVERS                  0x02
 153 #define LDC_HS_SENTRTR                  0x03
 154 #define LDC_HS_GOTRTR                   0x04
 155 #define LDC_HS_COMPLETE                 0x10
 156
 157         u8                              flags;
 158 #define LDC_FLAG_ALLOCED_QUEUES         0x01
 159 #define LDC_FLAG_REGISTERED_QUEUES      0x02
 160 #define LDC_FLAG_REGISTERED_IRQS        0x04
 161 #define LDC_FLAG_RESET                  0x10
 162
 163         u8                              mss;
 164         u8                              state;
 165
 166 #define LDC_IRQ_NAME_MAX                32
 167         char                            rx_irq_name[LDC_IRQ_NAME_MAX];
 168         char                            tx_irq_name[LDC_IRQ_NAME_MAX];
 169
 170         struct hlist_head               mh_list;
 171
 172         struct hlist_node               list;
 173 };
 174
 175 #define ldcdbg(TYPE, f, a...) \
 176 do {    if (lp->cfg.debug & LDC_DEBUG_##TYPE) \
 177                 printk(KERN_INFO PFX "ID[%lu] " f, lp->id, ## a); \
 178 } while (0)
 179
 180 #define LDC_ABORT(lp)   ldc_abort((lp), __func__)
 181
 182 static const char *state_to_str(u8 state)
 183 {
 184         switch (state) {
 185         case LDC_STATE_INVALID:
 186                 return "INVALID";
 187         case LDC_STATE_INIT:
 188                 return "INIT";
 189         case LDC_STATE_BOUND:
 190                 return "BOUND";
 191         case LDC_STATE_READY:
 192                 return "READY";
 193         case LDC_STATE_CONNECTED:
 194                 return "CONNECTED";
 195         default:
 196                 return "<UNKNOWN>";
 197         }
 198 }
 199
 200 static unsigned long __advance(unsigned long off, unsigned long num_entries)
 201 {
 202         off += LDC_PACKET_SIZE;
 203         if (off == (num_entries * LDC_PACKET_SIZE))
 204                 off = 0;
 205
 206         return off;
 207 }
 208
 209 static unsigned long rx_advance(struct ldc_channel *lp, unsigned long off)
 210 {
 211         return __advance(off, lp->rx_num_entries);
 212 }
 213
 214 static unsigned long tx_advance(struct ldc_channel *lp, unsigned long off)
 215 {
 216         return __advance(off, lp->tx_num_entries);
 217 }
 218
 219 static struct ldc_packet *handshake_get_tx_packet(struct ldc_channel *lp,
 220                                                   unsigned long *new_tail)
 221 {
 222         struct ldc_packet *p;
 223         unsigned long t;
 224
 225         t = tx_advance(lp, lp->tx_tail);
 226         if (t == lp->tx_head)
 227                 return NULL;
 228
 229         *new_tail = t;
 230
 231         p = lp->tx_base;
 232         return p + (lp->tx_tail / LDC_PACKET_SIZE);
 233 }
 234
 235 /* When we are in reliable or stream mode, have to track the next packet
 236  * we haven't gotten an ACK for in the TX queue using tx_acked.  We have
 237  * to be careful not to stomp over the queue past that point.  During
 238  * the handshake, we don't have TX data packets pending in the queue
 239  * and that's why handshake_get_tx_packet() need not be mindful of
 240  * lp->tx_acked.
 241  */
 242 static unsigned long head_for_data(struct ldc_channel *lp)
 243 {
 244         if (lp->cfg.mode == LDC_MODE_STREAM)
 245                 return lp->tx_acked;
 246         return lp->tx_head;
 247 }
 248
 249 static int tx_has_space_for(struct ldc_channel *lp, unsigned int size)
 250 {
 251         unsigned long limit, tail, new_tail, diff;
 252         unsigned int mss;
 253
 254         limit = head_for_data(lp);
 255         tail = lp->tx_tail;
 256         new_tail = tx_advance(lp, tail);
 257         if (new_tail == limit)
 258                 return 0;
 259
 260         if (limit > new_tail)
 261                 diff = limit - new_tail;
 262         else
 263                 diff = (limit +
 264                         ((lp->tx_num_entries * LDC_PACKET_SIZE) - new_tail));
 265         diff /= LDC_PACKET_SIZE;
 266         mss = lp->mss;
 267
 268         if (diff * mss < size)
 269                 return 0;
 270
 271         return 1;
 272 }
 273
 274 static struct ldc_packet *data_get_tx_packet(struct ldc_channel *lp,
 275                                              unsigned long *new_tail)
 276 {
 277         struct ldc_packet *p;
 278         unsigned long h, t;
 279
 280         h = head_for_data(lp);
 281         t = tx_advance(lp, lp->tx_tail);
 282         if (t == h)
 283                 return NULL;
 284
 285         *new_tail = t;
 286
 287         p = lp->tx_base;
 288         return p + (lp->tx_tail / LDC_PACKET_SIZE);
 289 }
 290
 291 static int set_tx_tail(struct ldc_channel *lp, unsigned long tail)
 292 {
 293         unsigned long orig_tail = lp->tx_tail;
 294         int limit = 1000;
 295
 296         lp->tx_tail = tail;
 297         while (limit-- > 0) {
 298                 unsigned long err;
 299
 300                 err = sun4v_ldc_tx_set_qtail(lp->id, tail);
 301                 if (!err)
 302                         return 0;
 303
 304                 if (err != HV_EWOULDBLOCK) {
 305                         lp->tx_tail = orig_tail;
 306                         return -EINVAL;
 307                 }
 308                 udelay(1);
 309         }
 310
 311         lp->tx_tail = orig_tail;
 312         return -EBUSY;
 313 }
 314
 315 /* This just updates the head value in the hypervisor using
 316  * a polling loop with a timeout.  The caller takes care of
 317  * upating software state representing the head change, if any.
 318  */
 319 static int __set_rx_head(struct ldc_channel *lp, unsigned long head)
 320 {
 321         int limit = 1000;
 322
 323         while (limit-- > 0) {
 324                 unsigned long err;
 325
 326                 err = sun4v_ldc_rx_set_qhead(lp->id, head);
 327                 if (!err)
 328                         return 0;
 329
 330                 if (err != HV_EWOULDBLOCK)
 331                         return -EINVAL;
 332
 333                 udelay(1);
 334         }
 335
 336         return -EBUSY;
 337 }
 338
 339 static int send_tx_packet(struct ldc_channel *lp,
 340                           struct ldc_packet *p,
 341                           unsigned long new_tail)
 342 {
 343         BUG_ON(p != (lp->tx_base + (lp->tx_tail / LDC_PACKET_SIZE)));
 344
 345         return set_tx_tail(lp, new_tail);
 346 }
 347
 348 static struct ldc_packet *handshake_compose_ctrl(struct ldc_channel *lp,
 349                                                  u8 stype, u8 ctrl,
 350                                                  void *data, int dlen,
 351                                                  unsigned long *new_tail)
 352 {
 353         struct ldc_packet *p = handshake_get_tx_packet(lp, new_tail);
 354
 355         if (p) {
 356                 memset(p, 0, sizeof(*p));
 357                 p->type = LDC_CTRL;
 358                 p->stype = stype;
 359                 p->ctrl = ctrl;
 360                 if (data)
 361                         memcpy(p->u.u_data, data, dlen);
 362         }
 363         return p;
 364 }
 365
 366 static int start_handshake(struct ldc_channel *lp)
 367 {
 368         struct ldc_packet *p;
 369         struct ldc_version *ver;
 370         unsigned long new_tail;
 371
 372         ver = &ver_arr[0];
 373
 374         ldcdbg(HS, "SEND VER INFO maj[%u] min[%u]\n",
 375                ver->major, ver->minor);
 376
 377         p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
 378                                    ver, sizeof(*ver), &new_tail);
 379         if (p) {
 380                 int err = send_tx_packet(lp, p, new_tail);
 381                 if (!err)
 382                         lp->flags &= ~LDC_FLAG_RESET;
 383                 return err;
 384         }
 385         return -EBUSY;
 386 }
 387
 388 static int send_version_nack(struct ldc_channel *lp,
 389                              u16 major, u16 minor)
 390 {
 391         struct ldc_packet *p;
 392         struct ldc_version ver;
 393         unsigned long new_tail;
 394
 395         ver.major = major;
 396         ver.minor = minor;
 397
 398         p = handshake_compose_ctrl(lp, LDC_NACK, LDC_VERS,
 399                                    &ver, sizeof(ver), &new_tail);
 400         if (p) {
 401                 ldcdbg(HS, "SEND VER NACK maj[%u] min[%u]\n",
 402                        ver.major, ver.minor);
 403
 404                 return send_tx_packet(lp, p, new_tail);
 405         }
 406         return -EBUSY;
 407 }
 408
 409 static int send_version_ack(struct ldc_channel *lp,
 410                             struct ldc_version *vp)
 411 {
 412         struct ldc_packet *p;
 413         unsigned long new_tail;
 414
 415         p = handshake_compose_ctrl(lp, LDC_ACK, LDC_VERS,
 416                                    vp, sizeof(*vp), &new_tail);
 417         if (p) {
 418                 ldcdbg(HS, "SEND VER ACK maj[%u] min[%u]\n",
 419                        vp->major, vp->minor);
 420
 421                 return send_tx_packet(lp, p, new_tail);
 422         }
 423         return -EBUSY;
 424 }
 425
 426 static int send_rts(struct ldc_channel *lp)
 427 {
 428         struct ldc_packet *p;
 429         unsigned long new_tail;
 430
 431         p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTS, NULL, 0,
 432                                    &new_tail);
 433         if (p) {
 434                 p->env = lp->cfg.mode;
 435                 p->seqid = 0;
 436                 lp->rcv_nxt = 0;
 437
 438                 ldcdbg(HS, "SEND RTS env[0x%x] seqid[0x%x]\n",
 439                        p->env, p->seqid);
 440
 441                 return send_tx_packet(lp, p, new_tail);
 442         }
 443         return -EBUSY;
 444 }
 445
 446 static int send_rtr(struct ldc_channel *lp)
 447 {
 448         struct ldc_packet *p;
 449         unsigned long new_tail;
 450
 451         p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTR, NULL, 0,
 452                                    &new_tail);
 453         if (p) {
 454                 p->env = lp->cfg.mode;
 455                 p->seqid = 0;
 456
 457                 ldcdbg(HS, "SEND RTR env[0x%x] seqid[0x%x]\n",
 458                        p->env, p->seqid);
 459
 460                 return send_tx_packet(lp, p, new_tail);
 461         }
 462         return -EBUSY;
 463 }
 464
 465 static int send_rdx(struct ldc_channel *lp)
 466 {
 467         struct ldc_packet *p;
 468         unsigned long new_tail;
 469
 470         p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RDX, NULL, 0,
 471                                    &new_tail);
 472         if (p) {
 473                 p->env = 0;
 474                 p->seqid = ++lp->snd_nxt;
 475                 p->u.r.ackid = lp->rcv_nxt;
 476
 477                 ldcdbg(HS, "SEND RDX env[0x%x] seqid[0x%x] ackid[0x%x]\n",
 478                        p->env, p->seqid, p->u.r.ackid);
 479
 480                 return send_tx_packet(lp, p, new_tail);
 481         }
 482         return -EBUSY;
 483 }
 484
 485 static int send_data_nack(struct ldc_channel *lp, struct ldc_packet *data_pkt)
 486 {
 487         struct ldc_packet *p;
 488         unsigned long new_tail;
 489         int err;
 490
 491         p = data_get_tx_packet(lp, &new_tail);
 492         if (!p)
 493                 return -EBUSY;
 494         memset(p, 0, sizeof(*p));
 495         p->type = data_pkt->type;
 496         p->stype = LDC_NACK;
 497         p->ctrl = data_pkt->ctrl & LDC_CTRL_MSK;
 498         p->seqid = lp->snd_nxt + 1;
 499         p->u.r.ackid = lp->rcv_nxt;
 500
 501         ldcdbg(HS, "SEND DATA NACK type[0x%x] ctl[0x%x] seq[0x%x] ack[0x%x]\n",
 502                p->type, p->ctrl, p->seqid, p->u.r.ackid);
 503
 504         err = send_tx_packet(lp, p, new_tail);
 505         if (!err)
 506                 lp->snd_nxt++;
 507
 508         return err;
 509 }
 510
 511 static int ldc_abort(struct ldc_channel *lp, const char *msg)
 512 {
 513         unsigned long hv_err;
 514
 515         ldcdbg(STATE, "ABORT[%s]\n", msg);
 516         ldc_print(lp);
 517
 518         /* We report but do not act upon the hypervisor errors because
 519          * there really isn't much we can do if they fail at this point.
 520          */
 521         hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
 522         if (hv_err)
 523                 printk(KERN_ERR PFX "ldc_abort: "
 524                        "sun4v_ldc_tx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
 525                        lp->id, lp->tx_ra, lp->tx_num_entries, hv_err);
 526
 527         hv_err = sun4v_ldc_tx_get_state(lp->id,
 528                                         &lp->tx_head,
 529                                         &lp->tx_tail,
 530                                         &lp->chan_state);
 531         if (hv_err)
 532                 printk(KERN_ERR PFX "ldc_abort: "
 533                        "sun4v_ldc_tx_get_state(%lx,...) failed, err=%lu\n",
 534                        lp->id, hv_err);
 535
 536         hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
 537         if (hv_err)
 538                 printk(KERN_ERR PFX "ldc_abort: "
 539                        "sun4v_ldc_rx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
 540                        lp->id, lp->rx_ra, lp->rx_num_entries, hv_err);
 541
 542         /* Refetch the RX queue state as well, because we could be invoked
 543          * here in the queue processing context.
 544          */
 545         hv_err = sun4v_ldc_rx_get_state(lp->id,
 546                                         &lp->rx_head,
 547                                         &lp->rx_tail,
 548                                         &lp->chan_state);
 549         if (hv_err)
 550                 printk(KERN_ERR PFX "ldc_abort: "
 551                        "sun4v_ldc_rx_get_state(%lx,...) failed, err=%lu\n",
 552                        lp->id, hv_err);
 553
 554         return -ECONNRESET;
 555 }
 556
 557 static struct ldc_version *find_by_major(u16 major)
 558 {
 559         struct ldc_version *ret = NULL;
 560         int i;
 561
 562         for (i = 0; i < ARRAY_SIZE(ver_arr); i++) {
 563                 struct ldc_version *v = &ver_arr[i];
 564                 if (v->major <= major) {
 565                         ret = v;
 566                         break;
 567                 }
 568         }
 569         return ret;
 570 }
 571
 572 static int process_ver_info(struct ldc_channel *lp, struct ldc_version *vp)
 573 {
 574         struct ldc_version *vap;
 575         int err;
 576
 577         ldcdbg(HS, "GOT VERSION INFO major[%x] minor[%x]\n",
 578                vp->major, vp->minor);
 579
 580         if (lp->hs_state == LDC_HS_GOTVERS) {
 581                 lp->hs_state = LDC_HS_OPEN;
 582                 memset(&lp->ver, 0, sizeof(lp->ver));
 583         }
 584
 585         vap = find_by_major(vp->major);
 586         if (!vap) {
 587                 err = send_version_nack(lp, 0, 0);
 588         } else if (vap->major != vp->major) {
 589                 err = send_version_nack(lp, vap->major, vap->minor);
 590         } else {
 591                 struct ldc_version ver = *vp;
 592                 if (ver.minor > vap->minor)
 593                         ver.minor = vap->minor;
 594                 err = send_version_ack(lp, &ver);
 595                 if (!err) {
 596                         lp->ver = ver;
 597                         lp->hs_state = LDC_HS_GOTVERS;
 598                 }
 599         }
 600         if (err)
 601                 return LDC_ABORT(lp);
 602
 603         return 0;
 604 }
 605
 606 static int process_ver_ack(struct ldc_channel *lp, struct ldc_version *vp)
 607 {
 608         ldcdbg(HS, "GOT VERSION ACK major[%x] minor[%x]\n",
 609                vp->major, vp->minor);
 610
 611         if (lp->hs_state == LDC_HS_GOTVERS) {
 612                 if (lp->ver.major != vp->major ||
 613                     lp->ver.minor != vp->minor)
 614                         return LDC_ABORT(lp);
 615         } else {
 616                 lp->ver = *vp;
 617                 lp->hs_state = LDC_HS_GOTVERS;
 618         }
 619         if (send_rts(lp))
 620                 return LDC_ABORT(lp);
 621         return 0;
 622 }
 623
 624 static int process_ver_nack(struct ldc_channel *lp, struct ldc_version *vp)
 625 {
 626         struct ldc_version *vap;
 627         struct ldc_packet *p;
 628         unsigned long new_tail;
 629
 630         if (vp->major == 0 && vp->minor == 0)
 631                 return LDC_ABORT(lp);
 632
 633         vap = find_by_major(vp->major);
 634         if (!vap)
 635                 return LDC_ABORT(lp);
 636
 637         p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
 638                                            vap, sizeof(*vap),
 639                                            &new_tail);
 640         if (!p)
 641                 return LDC_ABORT(lp);
 642
 643         return send_tx_packet(lp, p, new_tail);
 644 }
 645
 646 static int process_version(struct ldc_channel *lp,
 647                            struct ldc_packet *p)
 648 {
 649         struct ldc_version *vp;
 650
 651         vp = (struct ldc_version *) p->u.u_data;
 652
 653         switch (p->stype) {
 654         case LDC_INFO:
 655                 return process_ver_info(lp, vp);
 656
 657         case LDC_ACK:
 658                 return process_ver_ack(lp, vp);
 659
 660         case LDC_NACK:
 661                 return process_ver_nack(lp, vp);
 662
 663         default:
 664                 return LDC_ABORT(lp);
 665         }
 666 }
 667
 668 static int process_rts(struct ldc_channel *lp,
 669                        struct ldc_packet *p)
 670 {
 671         ldcdbg(HS, "GOT RTS stype[%x] seqid[%x] env[%x]\n",
 672                p->stype, p->seqid, p->env);
 673
 674         if (p->stype     != LDC_INFO       ||
 675             lp->hs_state != LDC_HS_GOTVERS ||
 676             p->env       != lp->cfg.mode)
 677                 return LDC_ABORT(lp);
 678
 679         lp->snd_nxt = p->seqid;
 680         lp->rcv_nxt = p->seqid;
 681         lp->hs_state = LDC_HS_SENTRTR;
 682         if (send_rtr(lp))
 683                 return LDC_ABORT(lp);
 684
 685         return 0;
 686 }
 687
 688 static int process_rtr(struct ldc_channel *lp,
 689                        struct ldc_packet *p)
 690 {
 691         ldcdbg(HS, "GOT RTR stype[%x] seqid[%x] env[%x]\n",
 692                p->stype, p->seqid, p->env);
 693
 694         if (p->stype     != LDC_INFO ||
 695             p->env       != lp->cfg.mode)
 696                 return LDC_ABORT(lp);
 697
 698         lp->snd_nxt = p->seqid;
 699         lp->hs_state = LDC_HS_COMPLETE;
 700         ldc_set_state(lp, LDC_STATE_CONNECTED);
 701         send_rdx(lp);
 702
 703         return LDC_EVENT_UP;
 704 }
 705
 706 static int rx_seq_ok(struct ldc_channel *lp, u32 seqid)
 707 {
 708         return lp->rcv_nxt + 1 == seqid;
 709 }
 710
 711 static int process_rdx(struct ldc_channel *lp,
 712                        struct ldc_packet *p)
 713 {
 714         ldcdbg(HS, "GOT RDX stype[%x] seqid[%x] env[%x] ackid[%x]\n",
 715                p->stype, p->seqid, p->env, p->u.r.ackid);
 716
 717         if (p->stype != LDC_INFO ||
 718             !(rx_seq_ok(lp, p->seqid)))
 719                 return LDC_ABORT(lp);
 720
 721         lp->rcv_nxt = p->seqid;
 722
 723         lp->hs_state = LDC_HS_COMPLETE;
 724         ldc_set_state(lp, LDC_STATE_CONNECTED);
 725
 726         return LDC_EVENT_UP;
 727 }
 728
 729 static int process_control_frame(struct ldc_channel *lp,
 730                                  struct ldc_packet *p)
 731 {
 732         switch (p->ctrl) {
 733         case LDC_VERS:
 734                 return process_version(lp, p);
 735
 736         case LDC_RTS:
 737                 return process_rts(lp, p);
 738
 739         case LDC_RTR:
 740                 return process_rtr(lp, p);
 741
 742         case LDC_RDX:
 743                 return process_rdx(lp, p);
 744
 745         default:
 746                 return LDC_ABORT(lp);
 747         }
 748 }
 749
 750 static int process_error_frame(struct ldc_channel *lp,
 751                                struct ldc_packet *p)
 752 {
 753         return LDC_ABORT(lp);
 754 }
 755
 756 static int process_data_ack(struct ldc_channel *lp,
 757                             struct ldc_packet *ack)
 758 {
 759         unsigned long head = lp->tx_acked;
 760         u32 ackid = ack->u.r.ackid;
 761
 762         while (1) {
 763                 struct ldc_packet *p = lp->tx_base + (head / LDC_PACKET_SIZE);
 764
 765                 head = tx_advance(lp, head);
 766
 767                 if (p->seqid == ackid) {
 768                         lp->tx_acked = head;
 769                         return 0;
 770                 }
 771                 if (head == lp->tx_tail)
 772                         return LDC_ABORT(lp);
 773         }
 774
 775         return 0;
 776 }
 777
 778 static void send_events(struct ldc_channel *lp, unsigned int event_mask)
 779 {
 780         if (event_mask & LDC_EVENT_RESET)
 781                 lp->cfg.event(lp->event_arg, LDC_EVENT_RESET);
 782         if (event_mask & LDC_EVENT_UP)
 783                 lp->cfg.event(lp->event_arg, LDC_EVENT_UP);
 784         if (event_mask & LDC_EVENT_DATA_READY)
 785                 lp->cfg.event(lp->event_arg, LDC_EVENT_DATA_READY);
 786 }
 787
 788 static irqreturn_t ldc_rx(int irq, void *dev_id)
 789 {
 790         struct ldc_channel *lp = dev_id;
 791         unsigned long orig_state, flags;
 792         unsigned int event_mask;
 793
 794         spin_lock_irqsave(&lp->lock, flags);
 795
 796         orig_state = lp->chan_state;
 797
 798         /* We should probably check for hypervisor errors here and
 799          * reset the LDC channel if we get one.
 800          */
 801         sun4v_ldc_rx_get_state(lp->id,
 802                                &lp->rx_head,
 803                                &lp->rx_tail,
 804                                &lp->chan_state);
 805
 806         ldcdbg(RX, "RX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
 807                orig_state, lp->chan_state, lp->rx_head, lp->rx_tail);
 808
 809         event_mask = 0;
 810
 811         if (lp->cfg.mode == LDC_MODE_RAW &&
 812             lp->chan_state == LDC_CHANNEL_UP) {
 813                 lp->hs_state = LDC_HS_COMPLETE;
 814                 ldc_set_state(lp, LDC_STATE_CONNECTED);
 815
 816                 /*
 817                  * Generate an LDC_EVENT_UP event if the channel
 818                  * was not already up.
 819                  */
 820                 if (orig_state != LDC_CHANNEL_UP) {
 821                         event_mask |= LDC_EVENT_UP;
 822                         orig_state = lp->chan_state;
 823                 }
 824         }
 825
 826         /* If we are in reset state, flush the RX queue and ignore
 827          * everything.
 828          */
 829         if (lp->flags & LDC_FLAG_RESET) {
 830                 (void) ldc_rx_reset(lp);
 831                 goto out;
 832         }
 833
 834         /* Once we finish the handshake, we let the ldc_read()
 835          * paths do all of the control frame and state management.
 836          * Just trigger the callback.
 837          */
 838         if (lp->hs_state == LDC_HS_COMPLETE) {
 839 handshake_complete:
 840                 if (lp->chan_state != orig_state) {
 841                         unsigned int event = LDC_EVENT_RESET;
 842
 843                         if (lp->chan_state == LDC_CHANNEL_UP)
 844                                 event = LDC_EVENT_UP;
 845
 846                         event_mask |= event;
 847                 }
 848                 if (lp->rx_head != lp->rx_tail)
 849                         event_mask |= LDC_EVENT_DATA_READY;
 850
 851                 goto out;
 852         }
 853
 854         if (lp->chan_state != orig_state)
 855                 goto out;
 856
 857         while (lp->rx_head != lp->rx_tail) {
 858                 struct ldc_packet *p;
 859                 unsigned long new;
 860                 int err;
 861
 862                 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
 863
 864                 switch (p->type) {
 865                 case LDC_CTRL:
 866                         err = process_control_frame(lp, p);
 867                         if (err > 0)
 868                                 event_mask |= err;
 869                         break;
 870
 871                 case LDC_DATA:
 872                         event_mask |= LDC_EVENT_DATA_READY;
 873                         err = 0;
 874                         break;
 875
 876                 case LDC_ERR:
 877                         err = process_error_frame(lp, p);
 878                         break;
 879
 880                 default:
 881                         err = LDC_ABORT(lp);
 882                         break;
 883                 }
 884
 885                 if (err < 0)
 886                         break;
 887
 888                 new = lp->rx_head;
 889                 new += LDC_PACKET_SIZE;
 890                 if (new == (lp->rx_num_entries * LDC_PACKET_SIZE))
 891                         new = 0;
 892                 lp->rx_head = new;
 893
 894                 err = __set_rx_head(lp, new);
 895                 if (err < 0) {
 896                         (void) LDC_ABORT(lp);
 897                         break;
 898                 }
 899                 if (lp->hs_state == LDC_HS_COMPLETE)
 900                         goto handshake_complete;
 901         }
 902
 903 out:
 904         spin_unlock_irqrestore(&lp->lock, flags);
 905
 906         send_events(lp, event_mask);
 907
 908         return IRQ_HANDLED;
 909 }
 910
 911 static irqreturn_t ldc_tx(int irq, void *dev_id)
 912 {
 913         struct ldc_channel *lp = dev_id;
 914         unsigned long flags, orig_state;
 915         unsigned int event_mask = 0;
 916
 917         spin_lock_irqsave(&lp->lock, flags);
 918
 919         orig_state = lp->chan_state;
 920
 921         /* We should probably check for hypervisor errors here and
 922          * reset the LDC channel if we get one.
 923          */
 924         sun4v_ldc_tx_get_state(lp->id,
 925                                &lp->tx_head,
 926                                &lp->tx_tail,
 927                                &lp->chan_state);
 928
 929         ldcdbg(TX, " TX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
 930                orig_state, lp->chan_state, lp->tx_head, lp->tx_tail);
 931
 932         if (lp->cfg.mode == LDC_MODE_RAW &&
 933             lp->chan_state == LDC_CHANNEL_UP) {
 934                 lp->hs_state = LDC_HS_COMPLETE;
 935                 ldc_set_state(lp, LDC_STATE_CONNECTED);
 936
 937                 /*
 938                  * Generate an LDC_EVENT_UP event if the channel
 939                  * was not already up.
 940                  */
 941                 if (orig_state != LDC_CHANNEL_UP) {
 942                         event_mask |= LDC_EVENT_UP;
 943                         orig_state = lp->chan_state;
 944                 }
 945         }
 946
 947         spin_unlock_irqrestore(&lp->lock, flags);
 948
 949         send_events(lp, event_mask);
 950
 951         return IRQ_HANDLED;
 952 }
 953
 954 /* XXX ldc_alloc() and ldc_free() needs to run under a mutex so
 955  * XXX that addition and removal from the ldc_channel_list has
 956  * XXX atomicity, otherwise the __ldc_channel_exists() check is
 957  * XXX totally pointless as another thread can slip into ldc_alloc()
 958  * XXX and add a channel with the same ID.  There also needs to be
 959  * XXX a spinlock for ldc_channel_list.
 960  */
 961 static HLIST_HEAD(ldc_channel_list);
 962
 963 static int __ldc_channel_exists(unsigned long id)
 964 {
 965         struct ldc_channel *lp;
 966
 967         hlist_for_each_entry(lp, &ldc_channel_list, list) {
 968                 if (lp->id == id)
 969                         return 1;
 970         }
 971         return 0;
 972 }
 973
 974 static int alloc_queue(const char *name, unsigned long num_entries,
 975                        struct ldc_packet **base, unsigned long *ra)
 976 {
 977         unsigned long size, order;
 978         void *q;
 979
 980         size = num_entries * LDC_PACKET_SIZE;
 981         order = get_order(size);
 982
 983         q = (void *) __get_free_pages(GFP_KERNEL, order);
 984         if (!q) {
 985                 printk(KERN_ERR PFX "Alloc of %s queue failed with "
 986                        "size=%lu order=%lu\n", name, size, order);
 987                 return -ENOMEM;
 988         }
 989
 990         memset(q, 0, PAGE_SIZE << order);
 991
 992         *base = q;
 993         *ra = __pa(q);
 994
 995         return 0;
 996 }
 997
 998 static void free_queue(unsigned long num_entries, struct ldc_packet *q)
 999 {
1000         unsigned long size, order;
1001
1002         if (!q)
1003                 return;
1004
1005         size = num_entries * LDC_PACKET_SIZE;
1006         order = get_order(size);
1007
1008         free_pages((unsigned long)q, order);
1009 }
1010
1011 static unsigned long ldc_cookie_to_index(u64 cookie, void *arg)
1012 {
1013         u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT;
1014         /* struct ldc_iommu *ldc_iommu = (struct ldc_iommu *)arg; */
1015
1016         cookie &= ~COOKIE_PGSZ_CODE;
1017
1018         return (cookie >> (13ULL + (szcode * 3ULL)));
1019 }
1020
1021 static void ldc_demap(struct ldc_iommu *iommu, unsigned long id, u64 cookie,
1022                       unsigned long entry, unsigned long npages)
1023 {
1024         struct ldc_mtable_entry *base;
1025         unsigned long i, shift;
1026
1027         shift = (cookie >> COOKIE_PGSZ_CODE_SHIFT) * 3;
1028         base = iommu->page_table + entry;
1029         for (i = 0; i < npages; i++) {
1030                 if (base->cookie)
1031                         sun4v_ldc_revoke(id, cookie + (i << shift),
1032                                          base->cookie);
1033                 base->mte = 0;
1034         }
1035 }
1036
1037 /* XXX Make this configurable... XXX */
1038 #define LDC_IOTABLE_SIZE        (8 * 1024)
1039
1040 static int ldc_iommu_init(const char *name, struct ldc_channel *lp)
1041 {
1042         unsigned long sz, num_tsb_entries, tsbsize, order;
1043         struct ldc_iommu *ldc_iommu = &lp->iommu;
1044         struct iommu_map_table *iommu = &ldc_iommu->iommu_map_table;
1045         struct ldc_mtable_entry *table;
1046         unsigned long hv_err;
1047         int err;
1048
1049         num_tsb_entries = LDC_IOTABLE_SIZE;
1050         tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1051         spin_lock_init(&ldc_iommu->lock);
1052
1053         sz = num_tsb_entries / 8;
1054         sz = (sz + 7UL) & ~7UL;
1055         iommu->map = kzalloc(sz, GFP_KERNEL);
1056         if (!iommu->map) {
1057                 printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz);
1058                 return -ENOMEM;
1059         }
1060         iommu_tbl_pool_init(iommu, num_tsb_entries, PAGE_SHIFT,
1061                             NULL, false /* no large pool */,
1062                             1 /* npools */,
1063                             true /* skip span boundary check */);
1064
1065         order = get_order(tsbsize);
1066
1067         table = (struct ldc_mtable_entry *)
1068                 __get_free_pages(GFP_KERNEL, order);
1069         err = -ENOMEM;
1070         if (!table) {
1071                 printk(KERN_ERR PFX "Alloc of MTE table failed, "
1072                        "size=%lu order=%lu\n", tsbsize, order);
1073                 goto out_free_map;
1074         }
1075
1076         memset(table, 0, PAGE_SIZE << order);
1077
1078         ldc_iommu->page_table = table;
1079
1080         hv_err = sun4v_ldc_set_map_table(lp->id, __pa(table),
1081                                          num_tsb_entries);
1082         err = -EINVAL;
1083         if (hv_err)
1084                 goto out_free_table;
1085
1086         return 0;
1087
1088 out_free_table:
1089         free_pages((unsigned long) table, order);
1090         ldc_iommu->page_table = NULL;
1091
1092 out_free_map:
1093         kfree(iommu->map);
1094         iommu->map = NULL;
1095
1096         return err;
1097 }
1098
1099 static void ldc_iommu_release(struct ldc_channel *lp)
1100 {
1101         struct ldc_iommu *ldc_iommu = &lp->iommu;
1102         struct iommu_map_table *iommu = &ldc_iommu->iommu_map_table;
1103         unsigned long num_tsb_entries, tsbsize, order;
1104
1105         (void) sun4v_ldc_set_map_table(lp->id, 0, 0);
1106
1107         num_tsb_entries = iommu->poolsize * iommu->nr_pools;
1108         tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1109         order = get_order(tsbsize);
1110
1111         free_pages((unsigned long) ldc_iommu->page_table, order);
1112         ldc_iommu->page_table = NULL;
1113
1114         kfree(iommu->map);
1115         iommu->map = NULL;
1116 }
1117
1118 struct ldc_channel *ldc_alloc(unsigned long id,
1119                               const struct ldc_channel_config *cfgp,
1120                               void *event_arg,
1121                               const char *name)
1122 {
1123         struct ldc_channel *lp;
1124         const struct ldc_mode_ops *mops;
1125         unsigned long dummy1, dummy2, hv_err;
1126         u8 mss, *mssbuf;
1127         int err;
1128
1129         err = -ENODEV;
1130         if (!ldom_domaining_enabled)
1131                 goto out_err;
1132
1133         err = -EINVAL;
1134         if (!cfgp)
1135                 goto out_err;
1136         if (!name)
1137                 goto out_err;
1138
1139         switch (cfgp->mode) {
1140         case LDC_MODE_RAW:
1141                 mops = &raw_ops;
1142                 mss = LDC_PACKET_SIZE;
1143                 break;
1144
1145         case LDC_MODE_UNRELIABLE:
1146                 mops = &nonraw_ops;
1147                 mss = LDC_PACKET_SIZE - 8;
1148                 break;
1149
1150         case LDC_MODE_STREAM:
1151                 mops = &stream_ops;
1152                 mss = LDC_PACKET_SIZE - 8 - 8;
1153                 break;
1154
1155         default:
1156                 goto out_err;
1157         }
1158
1159         if (!cfgp->event || !event_arg || !cfgp->rx_irq || !cfgp->tx_irq)
1160                 goto out_err;
1161
1162         hv_err = sun4v_ldc_tx_qinfo(id, &dummy1, &dummy2);
1163         err = -ENODEV;
1164         if (hv_err == HV_ECHANNEL)
1165                 goto out_err;
1166
1167         err = -EEXIST;
1168         if (__ldc_channel_exists(id))
1169                 goto out_err;
1170
1171         mssbuf = NULL;
1172
1173         lp = kzalloc(sizeof(*lp), GFP_KERNEL);
1174         err = -ENOMEM;
1175         if (!lp)
1176                 goto out_err;
1177
1178         spin_lock_init(&lp->lock);
1179
1180         lp->id = id;
1181
1182         err = ldc_iommu_init(name, lp);
1183         if (err)
1184                 goto out_free_ldc;
1185
1186         lp->mops = mops;
1187         lp->mss = mss;
1188
1189         lp->cfg = *cfgp;
1190         if (!lp->cfg.mtu)
1191                 lp->cfg.mtu = LDC_DEFAULT_MTU;
1192
1193         if (lp->cfg.mode == LDC_MODE_STREAM) {
1194                 mssbuf = kzalloc(lp->cfg.mtu, GFP_KERNEL);
1195                 if (!mssbuf) {
1196                         err = -ENOMEM;
1197                         goto out_free_iommu;
1198                 }
1199                 lp->mssbuf = mssbuf;
1200         }
1201
1202         lp->event_arg = event_arg;
1203
1204         /* XXX allow setting via ldc_channel_config to override defaults
1205          * XXX or use some formula based upon mtu
1206          */
1207         lp->tx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1208         lp->rx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1209
1210         err = alloc_queue("TX", lp->tx_num_entries,
1211                           &lp->tx_base, &lp->tx_ra);
1212         if (err)
1213                 goto out_free_mssbuf;
1214
1215         err = alloc_queue("RX", lp->rx_num_entries,
1216                           &lp->rx_base, &lp->rx_ra);
1217         if (err)
1218                 goto out_free_txq;
1219
1220         lp->flags |= LDC_FLAG_ALLOCED_QUEUES;
1221
1222         lp->hs_state = LDC_HS_CLOSED;
1223         ldc_set_state(lp, LDC_STATE_INIT);
1224
1225         INIT_HLIST_NODE(&lp->list);
1226         hlist_add_head(&lp->list, &ldc_channel_list);
1227
1228         INIT_HLIST_HEAD(&lp->mh_list);
1229
1230         snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name);
1231         snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name);
1232
1233         err = request_irq(lp->cfg.rx_irq, ldc_rx, 0,
1234                           lp->rx_irq_name, lp);
1235         if (err)
1236                 goto out_free_txq;
1237
1238         err = request_irq(lp->cfg.tx_irq, ldc_tx, 0,
1239                           lp->tx_irq_name, lp);
1240         if (err) {
1241                 free_irq(lp->cfg.rx_irq, lp);
1242                 goto out_free_txq;
1243         }
1244
1245         return lp;
1246
1247 out_free_txq:
1248         free_queue(lp->tx_num_entries, lp->tx_base);
1249
1250 out_free_mssbuf:
1251         kfree(mssbuf);
1252
1253 out_free_iommu:
1254         ldc_iommu_release(lp);
1255
1256 out_free_ldc:
1257         kfree(lp);
1258
1259 out_err:
1260         return ERR_PTR(err);
1261 }
1262 EXPORT_SYMBOL(ldc_alloc);
1263
1264 void ldc_unbind(struct ldc_channel *lp)
1265 {
1266         if (lp->flags & LDC_FLAG_REGISTERED_IRQS) {
1267                 free_irq(lp->cfg.rx_irq, lp);
1268                 free_irq(lp->cfg.tx_irq, lp);
1269                 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
1270         }
1271
1272         if (lp->flags & LDC_FLAG_REGISTERED_QUEUES) {
1273                 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1274                 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1275                 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1276         }
1277         if (lp->flags & LDC_FLAG_ALLOCED_QUEUES) {
1278                 free_queue(lp->tx_num_entries, lp->tx_base);
1279                 free_queue(lp->rx_num_entries, lp->rx_base);
1280                 lp->flags &= ~LDC_FLAG_ALLOCED_QUEUES;
1281         }
1282
1283         ldc_set_state(lp, LDC_STATE_INIT);
1284 }
1285 EXPORT_SYMBOL(ldc_unbind);
1286
1287 void ldc_free(struct ldc_channel *lp)
1288 {
1289         ldc_unbind(lp);
1290         hlist_del(&lp->list);
1291         kfree(lp->mssbuf);
1292         ldc_iommu_release(lp);
1293
1294         kfree(lp);
1295 }
1296 EXPORT_SYMBOL(ldc_free);
1297
1298 /* Bind the channel.  This registers the LDC queues with
1299  * the hypervisor and puts the channel into a pseudo-listening
1300  * state.  This does not initiate a handshake, ldc_connect() does
1301  * that.
1302  */
1303 int ldc_bind(struct ldc_channel *lp)
1304 {
1305         unsigned long hv_err, flags;
1306         int err = -EINVAL;
1307
1308         if (lp->state != LDC_STATE_INIT)
1309                 return -EINVAL;
1310
1311         spin_lock_irqsave(&lp->lock, flags);
1312
1313         enable_irq(lp->cfg.rx_irq);
1314         enable_irq(lp->cfg.tx_irq);
1315
1316         lp->flags |= LDC_FLAG_REGISTERED_IRQS;
1317
1318         err = -ENODEV;
1319         hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1320         if (hv_err)
1321                 goto out_free_irqs;
1322
1323         hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1324         if (hv_err)
1325                 goto out_free_irqs;
1326
1327         hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1328         if (hv_err)
1329                 goto out_unmap_tx;
1330
1331         hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1332         if (hv_err)
1333                 goto out_unmap_tx;
1334
1335         lp->flags |= LDC_FLAG_REGISTERED_QUEUES;
1336
1337         hv_err = sun4v_ldc_tx_get_state(lp->id,
1338                                         &lp->tx_head,
1339                                         &lp->tx_tail,
1340                                         &lp->chan_state);
1341         err = -EBUSY;
1342         if (hv_err)
1343                 goto out_unmap_rx;
1344
1345         lp->tx_acked = lp->tx_head;
1346
1347         lp->hs_state = LDC_HS_OPEN;
1348         ldc_set_state(lp, LDC_STATE_BOUND);
1349
1350         if (lp->cfg.mode == LDC_MODE_RAW) {
1351                 /*
1352                  * There is no handshake in RAW mode, so handshake
1353                  * is completed.
1354                  */
1355                 lp->hs_state = LDC_HS_COMPLETE;
1356         }
1357
1358         spin_unlock_irqrestore(&lp->lock, flags);
1359
1360         return 0;
1361
1362 out_unmap_rx:
1363         lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1364         sun4v_ldc_rx_qconf(lp->id, 0, 0);
1365
1366 out_unmap_tx:
1367         sun4v_ldc_tx_qconf(lp->id, 0, 0);
1368
1369 out_free_irqs:
1370         lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
1371         free_irq(lp->cfg.tx_irq, lp);
1372         free_irq(lp->cfg.rx_irq, lp);
1373
1374         spin_unlock_irqrestore(&lp->lock, flags);
1375
1376         return err;
1377 }
1378 EXPORT_SYMBOL(ldc_bind);
1379
1380 int ldc_connect(struct ldc_channel *lp)
1381 {
1382         unsigned long flags;
1383         int err;
1384
1385         if (lp->cfg.mode == LDC_MODE_RAW)
1386                 return -EINVAL;
1387
1388         spin_lock_irqsave(&lp->lock, flags);
1389
1390         if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1391             !(lp->flags & LDC_FLAG_REGISTERED_QUEUES) ||
1392             lp->hs_state != LDC_HS_OPEN)
1393                 err = ((lp->hs_state > LDC_HS_OPEN) ? 0 : -EINVAL);
1394         else
1395                 err = start_handshake(lp);
1396
1397         spin_unlock_irqrestore(&lp->lock, flags);
1398
1399         return err;
1400 }
1401 EXPORT_SYMBOL(ldc_connect);
1402
1403 int ldc_disconnect(struct ldc_channel *lp)
1404 {
1405         unsigned long hv_err, flags;
1406         int err;
1407
1408         if (lp->cfg.mode == LDC_MODE_RAW)
1409                 return -EINVAL;
1410
1411         if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1412             !(lp->flags & LDC_FLAG_REGISTERED_QUEUES))
1413                 return -EINVAL;
1414
1415         spin_lock_irqsave(&lp->lock, flags);
1416
1417         err = -ENODEV;
1418         hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1419         if (hv_err)
1420                 goto out_err;
1421
1422         hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1423         if (hv_err)
1424                 goto out_err;
1425
1426         hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1427         if (hv_err)
1428                 goto out_err;
1429
1430         hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1431         if (hv_err)
1432                 goto out_err;
1433
1434         ldc_set_state(lp, LDC_STATE_BOUND);
1435         lp->hs_state = LDC_HS_OPEN;
1436         lp->flags |= LDC_FLAG_RESET;
1437
1438         spin_unlock_irqrestore(&lp->lock, flags);
1439
1440         return 0;
1441
1442 out_err:
1443         sun4v_ldc_tx_qconf(lp->id, 0, 0);
1444         sun4v_ldc_rx_qconf(lp->id, 0, 0);
1445         free_irq(lp->cfg.tx_irq, lp);
1446         free_irq(lp->cfg.rx_irq, lp);
1447         lp->flags &= ~(LDC_FLAG_REGISTERED_IRQS |
1448                        LDC_FLAG_REGISTERED_QUEUES);
1449         ldc_set_state(lp, LDC_STATE_INIT);
1450
1451         spin_unlock_irqrestore(&lp->lock, flags);
1452
1453         return err;
1454 }
1455 EXPORT_SYMBOL(ldc_disconnect);
1456
1457 int ldc_state(struct ldc_channel *lp)
1458 {
1459         return lp->state;
1460 }
1461 EXPORT_SYMBOL(ldc_state);
1462
1463 void ldc_set_state(struct ldc_channel *lp, u8 state)
1464 {
1465         ldcdbg(STATE, "STATE (%s) --> (%s)\n",
1466                state_to_str(lp->state),
1467                state_to_str(state));
1468
1469         lp->state = state;
1470 }
1471 EXPORT_SYMBOL(ldc_set_state);
1472
1473 int ldc_mode(struct ldc_channel *lp)
1474 {
1475         return lp->cfg.mode;
1476 }
1477 EXPORT_SYMBOL(ldc_mode);
1478
1479 int ldc_rx_reset(struct ldc_channel *lp)
1480 {
1481         return __set_rx_head(lp, lp->rx_tail);
1482 }
1483
1484 void __ldc_print(struct ldc_channel *lp, const char *caller)
1485 {
1486         pr_info("%s: id=0x%lx flags=0x%x state=%s cstate=0x%lx hsstate=0x%x\n"
1487                 "\trx_h=0x%lx rx_t=0x%lx rx_n=%ld\n"
1488                 "\ttx_h=0x%lx tx_t=0x%lx tx_n=%ld\n"
1489                 "\trcv_nxt=%u snd_nxt=%u\n",
1490                 caller, lp->id, lp->flags, state_to_str(lp->state),
1491                 lp->chan_state, lp->hs_state,
1492                 lp->rx_head, lp->rx_tail, lp->rx_num_entries,
1493                 lp->tx_head, lp->tx_tail, lp->tx_num_entries,
1494                 lp->rcv_nxt, lp->snd_nxt);
1495 }
1496
1497 static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size)
1498 {
1499         struct ldc_packet *p;
1500         unsigned long new_tail, hv_err;
1501         int err;
1502
1503         hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail,
1504                                         &lp->chan_state);
1505         if (unlikely(hv_err))
1506                 return -EBUSY;
1507
1508         if (unlikely(lp->chan_state != LDC_CHANNEL_UP))
1509                 return LDC_ABORT(lp);
1510
1511         if (size > LDC_PACKET_SIZE)
1512                 return -EMSGSIZE;
1513
1514         p = data_get_tx_packet(lp, &new_tail);
1515         if (!p)
1516                 return -EAGAIN;
1517
1518         memcpy(p, buf, size);
1519
1520         err = send_tx_packet(lp, p, new_tail);
1521         if (!err)
1522                 err = size;
1523
1524         return err;
1525 }
1526
1527 static int read_raw(struct ldc_channel *lp, void *buf, unsigned int size)
1528 {
1529         struct ldc_packet *p;
1530         unsigned long hv_err, new;
1531         int err;
1532
1533         if (size < LDC_PACKET_SIZE)
1534                 return -EINVAL;
1535
1536         hv_err = sun4v_ldc_rx_get_state(lp->id,
1537                                         &lp->rx_head,
1538                                         &lp->rx_tail,
1539                                         &lp->chan_state);
1540         if (hv_err)
1541                 return LDC_ABORT(lp);
1542
1543         if (lp->chan_state == LDC_CHANNEL_DOWN ||
1544             lp->chan_state == LDC_CHANNEL_RESETTING)
1545                 return -ECONNRESET;
1546
1547         if (lp->rx_head == lp->rx_tail)
1548                 return 0;
1549
1550         p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
1551         memcpy(buf, p, LDC_PACKET_SIZE);
1552
1553         new = rx_advance(lp, lp->rx_head);
1554         lp->rx_head = new;
1555
1556         err = __set_rx_head(lp, new);
1557         if (err < 0)
1558                 err = -ECONNRESET;
1559         else
1560                 err = LDC_PACKET_SIZE;
1561
1562         return err;
1563 }
1564
1565 static const struct ldc_mode_ops raw_ops = {
1566         .write          =       write_raw,
1567         .read           =       read_raw,
1568 };
1569
1570 static int write_nonraw(struct ldc_channel *lp, const void *buf,
1571                         unsigned int size)
1572 {
1573         unsigned long hv_err, tail;
1574         unsigned int copied;
1575         u32 seq;
1576         int err;
1577
1578         hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail,
1579                                         &lp->chan_state);
1580         if (unlikely(hv_err))
1581                 return -EBUSY;
1582
1583         if (unlikely(lp->chan_state != LDC_CHANNEL_UP))
1584                 return LDC_ABORT(lp);
1585
1586         if (!tx_has_space_for(lp, size))
1587                 return -EAGAIN;
1588
1589         seq = lp->snd_nxt;
1590         copied = 0;
1591         tail = lp->tx_tail;
1592         while (copied < size) {
1593                 struct ldc_packet *p = lp->tx_base + (tail / LDC_PACKET_SIZE);
1594                 u8 *data = ((lp->cfg.mode == LDC_MODE_UNRELIABLE) ?
1595                             p->u.u_data :
1596                             p->u.r.r_data);
1597                 int data_len;
1598
1599                 p->type = LDC_DATA;
1600                 p->stype = LDC_INFO;
1601                 p->ctrl = 0;
1602
1603                 data_len = size - copied;
1604                 if (data_len > lp->mss)
1605                         data_len = lp->mss;
1606
1607                 BUG_ON(data_len > LDC_LEN);
1608
1609                 p->env = (data_len |
1610                           (copied == 0 ? LDC_START : 0) |
1611                           (data_len == size - copied ? LDC_STOP : 0));
1612
1613                 p->seqid = ++seq;
1614
1615                 ldcdbg(DATA, "SENT DATA [%02x:%02x:%02x:%02x:%08x]\n",
1616                        p->type,
1617                        p->stype,
1618                        p->ctrl,
1619                        p->env,
1620                        p->seqid);
1621
1622                 memcpy(data, buf, data_len);
1623                 buf += data_len;
1624                 copied += data_len;
1625
1626                 tail = tx_advance(lp, tail);
1627         }
1628
1629         err = set_tx_tail(lp, tail);
1630         if (!err) {
1631                 lp->snd_nxt = seq;
1632                 err = size;
1633         }
1634
1635         return err;
1636 }
1637
1638 static int rx_bad_seq(struct ldc_channel *lp, struct ldc_packet *p,
1639                       struct ldc_packet *first_frag)
1640 {
1641         int err;
1642
1643         if (first_frag)
1644                 lp->rcv_nxt = first_frag->seqid - 1;
1645
1646         err = send_data_nack(lp, p);
1647         if (err)
1648                 return err;
1649
1650         err = ldc_rx_reset(lp);
1651         if (err < 0)
1652                 return LDC_ABORT(lp);
1653
1654         return 0;
1655 }
1656
1657 static int data_ack_nack(struct ldc_channel *lp, struct ldc_packet *p)
1658 {
1659         if (p->stype & LDC_ACK) {
1660                 int err = process_data_ack(lp, p);
1661                 if (err)
1662                         return err;
1663         }
1664         if (p->stype & LDC_NACK)
1665                 return LDC_ABORT(lp);
1666
1667         return 0;
1668 }
1669
1670 static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head)
1671 {
1672         unsigned long dummy;
1673         int limit = 1000;
1674
1675         ldcdbg(DATA, "DATA WAIT cur_head[%lx] rx_head[%lx] rx_tail[%lx]\n",
1676                cur_head, lp->rx_head, lp->rx_tail);
1677         while (limit-- > 0) {
1678                 unsigned long hv_err;
1679
1680                 hv_err = sun4v_ldc_rx_get_state(lp->id,
1681                                                 &dummy,
1682                                                 &lp->rx_tail,
1683                                                 &lp->chan_state);
1684                 if (hv_err)
1685                         return LDC_ABORT(lp);
1686
1687                 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1688                     lp->chan_state == LDC_CHANNEL_RESETTING)
1689                         return -ECONNRESET;
1690
1691                 if (cur_head != lp->rx_tail) {
1692                         ldcdbg(DATA, "DATA WAIT DONE "
1693                                "head[%lx] tail[%lx] chan_state[%lx]\n",
1694                                dummy, lp->rx_tail, lp->chan_state);
1695                         return 0;
1696                 }
1697
1698                 udelay(1);
1699         }
1700         return -EAGAIN;
1701 }
1702
1703 static int rx_set_head(struct ldc_channel *lp, unsigned long head)
1704 {
1705         int err = __set_rx_head(lp, head);
1706
1707         if (err < 0)
1708                 return LDC_ABORT(lp);
1709
1710         lp->rx_head = head;
1711         return 0;
1712 }
1713
1714 static void send_data_ack(struct ldc_channel *lp)
1715 {
1716         unsigned long new_tail;
1717         struct ldc_packet *p;
1718
1719         p = data_get_tx_packet(lp, &new_tail);
1720         if (likely(p)) {
1721                 int err;
1722
1723                 memset(p, 0, sizeof(*p));
1724                 p->type = LDC_DATA;
1725                 p->stype = LDC_ACK;
1726                 p->ctrl = 0;
1727                 p->seqid = lp->snd_nxt + 1;
1728                 p->u.r.ackid = lp->rcv_nxt;
1729
1730                 err = send_tx_packet(lp, p, new_tail);
1731                 if (!err)
1732                         lp->snd_nxt++;
1733         }
1734 }
1735
1736 static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
1737 {
1738         struct ldc_packet *first_frag;
1739         unsigned long hv_err, new;
1740         int err, copied;
1741
1742         hv_err = sun4v_ldc_rx_get_state(lp->id,
1743                                         &lp->rx_head,
1744                                         &lp->rx_tail,
1745                                         &lp->chan_state);
1746         if (hv_err)
1747                 return LDC_ABORT(lp);
1748
1749         if (lp->chan_state == LDC_CHANNEL_DOWN ||
1750             lp->chan_state == LDC_CHANNEL_RESETTING)
1751                 return -ECONNRESET;
1752
1753         if (lp->rx_head == lp->rx_tail)
1754                 return 0;
1755
1756         first_frag = NULL;
1757         copied = err = 0;
1758         new = lp->rx_head;
1759         while (1) {
1760                 struct ldc_packet *p;
1761                 int pkt_len;
1762
1763                 BUG_ON(new == lp->rx_tail);
1764                 p = lp->rx_base + (new / LDC_PACKET_SIZE);
1765
1766                 ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x:%08x] "
1767                        "rcv_nxt[%08x]\n",
1768                        p->type,
1769                        p->stype,
1770                        p->ctrl,
1771                        p->env,
1772                        p->seqid,
1773                        p->u.r.ackid,
1774                        lp->rcv_nxt);
1775
1776                 if (unlikely(!rx_seq_ok(lp, p->seqid))) {
1777                         err = rx_bad_seq(lp, p, first_frag);
1778                         copied = 0;
1779                         break;
1780                 }
1781
1782                 if (p->type & LDC_CTRL) {
1783                         err = process_control_frame(lp, p);
1784                         if (err < 0)
1785                                 break;
1786                         err = 0;
1787                 }
1788
1789                 lp->rcv_nxt = p->seqid;
1790
1791                 /*
1792                  * If this is a control-only packet, there is nothing
1793                  * else to do but advance the rx queue since the packet
1794                  * was already processed above.
1795                  */
1796                 if (!(p->type & LDC_DATA)) {
1797                         new = rx_advance(lp, new);
1798                         break;
1799                 }
1800                 if (p->stype & (LDC_ACK | LDC_NACK)) {
1801                         err = data_ack_nack(lp, p);
1802                         if (err)
1803                                 break;
1804                 }
1805                 if (!(p->stype & LDC_INFO)) {
1806                         new = rx_advance(lp, new);
1807                         err = rx_set_head(lp, new);
1808                         if (err)
1809                                 break;
1810                         goto no_data;
1811                 }
1812
1813                 pkt_len = p->env & LDC_LEN;
1814
1815                 /* Every initial packet starts with the START bit set.
1816                  *
1817                  * Singleton packets will have both START+STOP set.
1818                  *
1819                  * Fragments will have START set in the first frame, STOP
1820                  * set in the last frame, and neither bit set in middle
1821                  * frames of the packet.
1822                  *
1823                  * Therefore if we are at the beginning of a packet and
1824                  * we don't see START, or we are in the middle of a fragmented
1825                  * packet and do see START, we are unsynchronized and should
1826                  * flush the RX queue.
1827                  */
1828                 if ((first_frag == NULL && !(p->env & LDC_START)) ||
1829                     (first_frag != NULL &&  (p->env & LDC_START))) {
1830                         if (!first_frag)
1831                                 new = rx_advance(lp, new);
1832
1833                         err = rx_set_head(lp, new);
1834                         if (err)
1835                                 break;
1836
1837                         if (!first_frag)
1838                                 goto no_data;
1839                 }
1840                 if (!first_frag)
1841                         first_frag = p;
1842
1843                 if (pkt_len > size - copied) {
1844                         /* User didn't give us a big enough buffer,
1845                          * what to do?  This is a pretty serious error.
1846                          *
1847                          * Since we haven't updated the RX ring head to
1848                          * consume any of the packets, signal the error
1849                          * to the user and just leave the RX ring alone.
1850                          *
1851                          * This seems the best behavior because this allows
1852                          * a user of the LDC layer to start with a small
1853                          * RX buffer for ldc_read() calls and use -EMSGSIZE
1854                          * as a cue to enlarge it's read buffer.
1855                          */
1856                         err = -EMSGSIZE;
1857                         break;
1858                 }
1859
1860                 /* Ok, we are gonna eat this one.  */
1861                 new = rx_advance(lp, new);
1862
1863                 memcpy(buf,
1864                        (lp->cfg.mode == LDC_MODE_UNRELIABLE ?
1865                         p->u.u_data : p->u.r.r_data), pkt_len);
1866                 buf += pkt_len;
1867                 copied += pkt_len;
1868
1869                 if (p->env & LDC_STOP)
1870                         break;
1871
1872 no_data:
1873                 if (new == lp->rx_tail) {
1874                         err = rx_data_wait(lp, new);
1875                         if (err)
1876                                 break;
1877                 }
1878         }
1879
1880         if (!err)
1881                 err = rx_set_head(lp, new);
1882
1883         if (err && first_frag)
1884                 lp->rcv_nxt = first_frag->seqid - 1;
1885
1886         if (!err) {
1887                 err = copied;
1888                 if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE)
1889                         send_data_ack(lp);
1890         }
1891
1892         return err;
1893 }
1894
1895 static const struct ldc_mode_ops nonraw_ops = {
1896         .write          =       write_nonraw,
1897         .read           =       read_nonraw,
1898 };
1899
1900 static int write_stream(struct ldc_channel *lp, const void *buf,
1901                         unsigned int size)
1902 {
1903         if (size > lp->cfg.mtu)
1904                 size = lp->cfg.mtu;
1905         return write_nonraw(lp, buf, size);
1906 }
1907
1908 static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size)
1909 {
1910         if (!lp->mssbuf_len) {
1911                 int err = read_nonraw(lp, lp->mssbuf, lp->cfg.mtu);
1912                 if (err < 0)
1913                         return err;
1914
1915                 lp->mssbuf_len = err;
1916                 lp->mssbuf_off = 0;
1917         }
1918
1919         if (size > lp->mssbuf_len)
1920                 size = lp->mssbuf_len;
1921         memcpy(buf, lp->mssbuf + lp->mssbuf_off, size);
1922
1923         lp->mssbuf_off += size;
1924         lp->mssbuf_len -= size;
1925
1926         return size;
1927 }
1928
1929 static const struct ldc_mode_ops stream_ops = {
1930         .write          =       write_stream,
1931         .read           =       read_stream,
1932 };
1933
1934 int ldc_write(struct ldc_channel *lp, const void *buf, unsigned int size)
1935 {
1936         unsigned long flags;
1937         int err;
1938
1939         if (!buf)
1940                 return -EINVAL;
1941
1942         if (!size)
1943                 return 0;
1944
1945         spin_lock_irqsave(&lp->lock, flags);
1946
1947         if (lp->hs_state != LDC_HS_COMPLETE)
1948                 err = -ENOTCONN;
1949         else
1950                 err = lp->mops->write(lp, buf, size);
1951
1952         spin_unlock_irqrestore(&lp->lock, flags);
1953
1954         return err;
1955 }
1956 EXPORT_SYMBOL(ldc_write);
1957
1958 int ldc_read(struct ldc_channel *lp, void *buf, unsigned int size)
1959 {
1960         unsigned long flags;
1961         int err;
1962
1963         ldcdbg(RX, "%s: entered size=%d\n", __func__, size);
1964
1965         if (!buf)
1966                 return -EINVAL;
1967
1968         if (!size)
1969                 return 0;
1970
1971         spin_lock_irqsave(&lp->lock, flags);
1972
1973         if (lp->hs_state != LDC_HS_COMPLETE)
1974                 err = -ENOTCONN;
1975         else
1976                 err = lp->mops->read(lp, buf, size);
1977
1978         spin_unlock_irqrestore(&lp->lock, flags);
1979
1980         ldcdbg(RX, "%s: mode=%d, head=%lu, tail=%lu rv=%d\n", __func__,
1981                lp->cfg.mode, lp->rx_head, lp->rx_tail, err);
1982
1983         return err;
1984 }
1985 EXPORT_SYMBOL(ldc_read);
1986
1987 static u64 pagesize_code(void)
1988 {
1989         switch (PAGE_SIZE) {
1990         default:
1991         case (8ULL * 1024ULL):
1992                 return 0;
1993         case (64ULL * 1024ULL):
1994                 return 1;
1995         case (512ULL * 1024ULL):
1996                 return 2;
1997         case (4ULL * 1024ULL * 1024ULL):
1998                 return 3;
1999         case (32ULL * 1024ULL * 1024ULL):
2000                 return 4;
2001         case (256ULL * 1024ULL * 1024ULL):
2002                 return 5;
2003         }
2004 }
2005
2006 static u64 make_cookie(u64 index, u64 pgsz_code, u64 page_offset)
2007 {
2008         return ((pgsz_code << COOKIE_PGSZ_CODE_SHIFT) |
2009                 (index << PAGE_SHIFT) |
2010                 page_offset);
2011 }
2012
2013
2014 static struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu,
2015                                              unsigned long npages)
2016 {
2017         long entry;
2018
2019         entry = iommu_tbl_range_alloc(NULL, &iommu->iommu_map_table,
2020                                       npages, NULL, (unsigned long)-1, 0);
2021         if (unlikely(entry == IOMMU_ERROR_CODE))
2022                 return NULL;
2023
2024         return iommu->page_table + entry;
2025 }
2026
2027 static u64 perm_to_mte(unsigned int map_perm)
2028 {
2029         u64 mte_base;
2030
2031         mte_base = pagesize_code();
2032
2033         if (map_perm & LDC_MAP_SHADOW) {
2034                 if (map_perm & LDC_MAP_R)
2035                         mte_base |= LDC_MTE_COPY_R;
2036                 if (map_perm & LDC_MAP_W)
2037                         mte_base |= LDC_MTE_COPY_W;
2038         }
2039         if (map_perm & LDC_MAP_DIRECT) {
2040                 if (map_perm & LDC_MAP_R)
2041                         mte_base |= LDC_MTE_READ;
2042                 if (map_perm & LDC_MAP_W)
2043                         mte_base |= LDC_MTE_WRITE;
2044                 if (map_perm & LDC_MAP_X)
2045                         mte_base |= LDC_MTE_EXEC;
2046         }
2047         if (map_perm & LDC_MAP_IO) {
2048                 if (map_perm & LDC_MAP_R)
2049                         mte_base |= LDC_MTE_IOMMU_R;
2050                 if (map_perm & LDC_MAP_W)
2051                         mte_base |= LDC_MTE_IOMMU_W;
2052         }
2053
2054         return mte_base;
2055 }
2056
2057 static int pages_in_region(unsigned long base, long len)
2058 {
2059         int count = 0;
2060
2061         do {
2062                 unsigned long new = (base + PAGE_SIZE) & PAGE_MASK;
2063
2064                 len -= (new - base);
2065                 base = new;
2066                 count++;
2067         } while (len > 0);
2068
2069         return count;
2070 }
2071
2072 struct cookie_state {
2073         struct ldc_mtable_entry         *page_table;
2074         struct ldc_trans_cookie         *cookies;
2075         u64                             mte_base;
2076         u64                             prev_cookie;
2077         u32                             pte_idx;
2078         u32                             nc;
2079 };
2080
2081 static void fill_cookies(struct cookie_state *sp, unsigned long pa,
2082                          unsigned long off, unsigned long len)
2083 {
2084         do {
2085                 unsigned long tlen, new = pa + PAGE_SIZE;
2086                 u64 this_cookie;
2087
2088                 sp->page_table[sp->pte_idx].mte = sp->mte_base | pa;
2089
2090                 tlen = PAGE_SIZE;
2091                 if (off)
2092                         tlen = PAGE_SIZE - off;
2093                 if (tlen > len)
2094                         tlen = len;
2095
2096                 this_cookie = make_cookie(sp->pte_idx,
2097                                           pagesize_code(), off);
2098
2099                 off = 0;
2100
2101                 if (this_cookie == sp->prev_cookie) {
2102                         sp->cookies[sp->nc - 1].cookie_size += tlen;
2103                 } else {
2104                         sp->cookies[sp->nc].cookie_addr = this_cookie;
2105                         sp->cookies[sp->nc].cookie_size = tlen;
2106                         sp->nc++;
2107                 }
2108                 sp->prev_cookie = this_cookie + tlen;
2109
2110                 sp->pte_idx++;
2111
2112                 len -= tlen;
2113                 pa = new;
2114         } while (len > 0);
2115 }
2116
2117 static int sg_count_one(struct scatterlist *sg)
2118 {
2119         unsigned long base = page_to_pfn(sg_page(sg)) << PAGE_SHIFT;
2120         long len = sg->length;
2121
2122         if ((sg->offset | len) & (8UL - 1))
2123                 return -EFAULT;
2124
2125         return pages_in_region(base + sg->offset, len);
2126 }
2127
2128 static int sg_count_pages(struct scatterlist *sg, int num_sg)
2129 {
2130         int count;
2131         int i;
2132
2133         count = 0;
2134         for (i = 0; i < num_sg; i++) {
2135                 int err = sg_count_one(sg + i);
2136                 if (err < 0)
2137                         return err;
2138                 count += err;
2139         }
2140
2141         return count;
2142 }
2143
2144 int ldc_map_sg(struct ldc_channel *lp,
2145                struct scatterlist *sg, int num_sg,
2146                struct ldc_trans_cookie *cookies, int ncookies,
2147                unsigned int map_perm)
2148 {
2149         unsigned long i, npages;
2150         struct ldc_mtable_entry *base;
2151         struct cookie_state state;
2152         struct ldc_iommu *iommu;
2153         int err;
2154         struct scatterlist *s;
2155
2156         if (map_perm & ~LDC_MAP_ALL)
2157                 return -EINVAL;
2158
2159         err = sg_count_pages(sg, num_sg);
2160         if (err < 0)
2161                 return err;
2162
2163         npages = err;
2164         if (err > ncookies)
2165                 return -EMSGSIZE;
2166
2167         iommu = &lp->iommu;
2168
2169         base = alloc_npages(iommu, npages);
2170
2171         if (!base)
2172                 return -ENOMEM;
2173
2174         state.page_table = iommu->page_table;
2175         state.cookies = cookies;
2176         state.mte_base = perm_to_mte(map_perm);
2177         state.prev_cookie = ~(u64)0;
2178         state.pte_idx = (base - iommu->page_table);
2179         state.nc = 0;
2180
2181         for_each_sg(sg, s, num_sg, i) {
2182                 fill_cookies(&state, page_to_pfn(sg_page(s)) << PAGE_SHIFT,
2183                              s->offset, s->length);
2184         }
2185
2186         return state.nc;
2187 }
2188 EXPORT_SYMBOL(ldc_map_sg);
2189
2190 int ldc_map_single(struct ldc_channel *lp,
2191                    void *buf, unsigned int len,
2192                    struct ldc_trans_cookie *cookies, int ncookies,
2193                    unsigned int map_perm)
2194 {
2195         unsigned long npages, pa;
2196         struct ldc_mtable_entry *base;
2197         struct cookie_state state;
2198         struct ldc_iommu *iommu;
2199
2200         if ((map_perm & ~LDC_MAP_ALL) || (ncookies < 1))
2201                 return -EINVAL;
2202
2203         pa = __pa(buf);
2204         if ((pa | len) & (8UL - 1))
2205                 return -EFAULT;
2206
2207         npages = pages_in_region(pa, len);
2208
2209         iommu = &lp->iommu;
2210
2211         base = alloc_npages(iommu, npages);
2212
2213         if (!base)
2214                 return -ENOMEM;
2215
2216         state.page_table = iommu->page_table;
2217         state.cookies = cookies;
2218         state.mte_base = perm_to_mte(map_perm);
2219         state.prev_cookie = ~(u64)0;
2220         state.pte_idx = (base - iommu->page_table);
2221         state.nc = 0;
2222         fill_cookies(&state, (pa & PAGE_MASK), (pa & ~PAGE_MASK), len);
2223         BUG_ON(state.nc > ncookies);
2224
2225         return state.nc;
2226 }
2227 EXPORT_SYMBOL(ldc_map_single);
2228
2229
2230 static void free_npages(unsigned long id, struct ldc_iommu *iommu,
2231                         u64 cookie, u64 size)
2232 {
2233         unsigned long npages, entry;
2234
2235         npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT;
2236
2237         entry = ldc_cookie_to_index(cookie, iommu);
2238         ldc_demap(iommu, id, cookie, entry, npages);
2239         iommu_tbl_range_free(&iommu->iommu_map_table, cookie, npages, entry);
2240 }
2241
2242 void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies,
2243                int ncookies)
2244 {
2245         struct ldc_iommu *iommu = &lp->iommu;
2246         int i;
2247         unsigned long flags;
2248
2249         spin_lock_irqsave(&iommu->lock, flags);
2250         for (i = 0; i < ncookies; i++) {
2251                 u64 addr = cookies[i].cookie_addr;
2252                 u64 size = cookies[i].cookie_size;
2253
2254                 free_npages(lp->id, iommu, addr, size);
2255         }
2256         spin_unlock_irqrestore(&iommu->lock, flags);
2257 }
2258 EXPORT_SYMBOL(ldc_unmap);
2259
2260 int ldc_copy(struct ldc_channel *lp, int copy_dir,
2261              void *buf, unsigned int len, unsigned long offset,
2262              struct ldc_trans_cookie *cookies, int ncookies)
2263 {
2264         unsigned int orig_len;
2265         unsigned long ra;
2266         int i;
2267
2268         if (copy_dir != LDC_COPY_IN && copy_dir != LDC_COPY_OUT) {
2269                 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Bad copy_dir[%d]\n",
2270                        lp->id, copy_dir);
2271                 return -EINVAL;
2272         }
2273
2274         ra = __pa(buf);
2275         if ((ra | len | offset) & (8UL - 1)) {
2276                 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Unaligned buffer "
2277                        "ra[%lx] len[%x] offset[%lx]\n",
2278                        lp->id, ra, len, offset);
2279                 return -EFAULT;
2280         }
2281
2282         if (lp->hs_state != LDC_HS_COMPLETE ||
2283             (lp->flags & LDC_FLAG_RESET)) {
2284                 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Link down hs_state[%x] "
2285                        "flags[%x]\n", lp->id, lp->hs_state, lp->flags);
2286                 return -ECONNRESET;
2287         }
2288
2289         orig_len = len;
2290         for (i = 0; i < ncookies; i++) {
2291                 unsigned long cookie_raddr = cookies[i].cookie_addr;
2292                 unsigned long this_len = cookies[i].cookie_size;
2293                 unsigned long actual_len;
2294
2295                 if (unlikely(offset)) {
2296                         unsigned long this_off = offset;
2297
2298                         if (this_off > this_len)
2299                                 this_off = this_len;
2300
2301                         offset -= this_off;
2302                         this_len -= this_off;
2303                         if (!this_len)
2304                                 continue;
2305                         cookie_raddr += this_off;
2306                 }
2307
2308                 if (this_len > len)
2309                         this_len = len;
2310
2311                 while (1) {
2312                         unsigned long hv_err;
2313
2314                         hv_err = sun4v_ldc_copy(lp->id, copy_dir,
2315                                                 cookie_raddr, ra,
2316                                                 this_len, &actual_len);
2317                         if (unlikely(hv_err)) {
2318                                 printk(KERN_ERR PFX "ldc_copy: ID[%lu] "
2319                                        "HV error %lu\n",
2320                                        lp->id, hv_err);
2321                                 if (lp->hs_state != LDC_HS_COMPLETE ||
2322                                     (lp->flags & LDC_FLAG_RESET))
2323                                         return -ECONNRESET;
2324                                 else
2325                                         return -EFAULT;
2326                         }
2327
2328                         cookie_raddr += actual_len;
2329                         ra += actual_len;
2330                         len -= actual_len;
2331                         if (actual_len == this_len)
2332                                 break;
2333
2334                         this_len -= actual_len;
2335                 }
2336
2337                 if (!len)
2338                         break;
2339         }
2340
2341         /* It is caller policy what to do about short copies.
2342          * For example, a networking driver can declare the
2343          * packet a runt and drop it.
2344          */
2345
2346         return orig_len - len;
2347 }
2348 EXPORT_SYMBOL(ldc_copy);
2349
2350 void *ldc_alloc_exp_dring(struct ldc_channel *lp, unsigned int len,
2351                           struct ldc_trans_cookie *cookies, int *ncookies,
2352                           unsigned int map_perm)
2353 {
2354         void *buf;
2355         int err;
2356
2357         if (len & (8UL - 1))
2358                 return ERR_PTR(-EINVAL);
2359
2360         buf = kzalloc(len, GFP_ATOMIC);
2361         if (!buf)
2362                 return ERR_PTR(-ENOMEM);
2363
2364         err = ldc_map_single(lp, buf, len, cookies, *ncookies, map_perm);
2365         if (err < 0) {
2366                 kfree(buf);
2367                 return ERR_PTR(err);
2368         }
2369         *ncookies = err;
2370
2371         return buf;
2372 }
2373 EXPORT_SYMBOL(ldc_alloc_exp_dring);
2374
2375 void ldc_free_exp_dring(struct ldc_channel *lp, void *buf, unsigned int len,
2376                         struct ldc_trans_cookie *cookies, int ncookies)
2377 {
2378         ldc_unmap(lp, cookies, ncookies);
2379         kfree(buf);
2380 }
2381 EXPORT_SYMBOL(ldc_free_exp_dring);
2382
2383 static int __init ldc_init(void)
2384 {
2385         unsigned long major, minor;
2386         struct mdesc_handle *hp;
2387         const u64 *v;
2388         int err;
2389         u64 mp;
2390
2391         hp = mdesc_grab();
2392         if (!hp)
2393                 return -ENODEV;
2394
2395         mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
2396         err = -ENODEV;
2397         if (mp == MDESC_NODE_NULL)
2398                 goto out;
2399
2400         v = mdesc_get_property(hp, mp, "domaining-enabled", NULL);
2401         if (!v)
2402                 goto out;
2403
2404         major = 1;
2405         minor = 0;
2406         if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) {
2407                 printk(KERN_INFO PFX "Could not register LDOM hvapi.\n");
2408                 goto out;
2409         }
2410
2411         printk(KERN_INFO "%s", version);
2412
2413         if (!*v) {
2414                 printk(KERN_INFO PFX "Domaining disabled.\n");
2415                 goto out;
2416         }
2417         ldom_domaining_enabled = 1;
2418         err = 0;
2419
2420 out:
2421         mdesc_release(hp);
2422         return err;
2423 }
2424
2425 core_initcall(ldc_init);