kernel/drivers/staging/rdma/ipath/ipath_user_sdma.c

   1 /*
   2  * Copyright (c) 2007, 2008 QLogic Corporation. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32 #include <linux/mm.h>
  33 #include <linux/types.h>
  34 #include <linux/device.h>
  35 #include <linux/dmapool.h>
  36 #include <linux/slab.h>
  37 #include <linux/list.h>
  38 #include <linux/highmem.h>
  39 #include <linux/io.h>
  40 #include <linux/uio.h>
  41 #include <linux/rbtree.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/delay.h>
  44
  45 #include "ipath_kernel.h"
  46 #include "ipath_user_sdma.h"
  47
  48 /* minimum size of header */
  49 #define IPATH_USER_SDMA_MIN_HEADER_LENGTH       64
  50 /* expected size of headers (for dma_pool) */
  51 #define IPATH_USER_SDMA_EXP_HEADER_LENGTH       64
  52 /* length mask in PBC (lower 11 bits) */
  53 #define IPATH_PBC_LENGTH_MASK                   ((1 << 11) - 1)
  54
  55 struct ipath_user_sdma_pkt {
  56         u8 naddr;               /* dimension of addr (1..3) ... */
  57         u32 counter;            /* sdma pkts queued counter for this entry */
  58         u64 added;              /* global descq number of entries */
  59
  60         struct {
  61                 u32 offset;                     /* offset for kvaddr, addr */
  62                 u32 length;                     /* length in page */
  63                 u8  put_page;                   /* should we put_page? */
  64                 u8  dma_mapped;                 /* is page dma_mapped? */
  65                 struct page *page;              /* may be NULL (coherent mem) */
  66                 void *kvaddr;                   /* FIXME: only for pio hack */
  67                 dma_addr_t addr;
  68         } addr[4];   /* max pages, any more and we coalesce */
  69         struct list_head list;  /* list element */
  70 };
  71
  72 struct ipath_user_sdma_queue {
  73         /*
  74          * pkts sent to dma engine are queued on this
  75          * list head.  the type of the elements of this
  76          * list are struct ipath_user_sdma_pkt...
  77          */
  78         struct list_head sent;
  79
  80         /* headers with expected length are allocated from here... */
  81         char header_cache_name[64];
  82         struct dma_pool *header_cache;
  83
  84         /* packets are allocated from the slab cache... */
  85         char pkt_slab_name[64];
  86         struct kmem_cache *pkt_slab;
  87
  88         /* as packets go on the queued queue, they are counted... */
  89         u32 counter;
  90         u32 sent_counter;
  91
  92         /* dma page table */
  93         struct rb_root dma_pages_root;
  94
  95         /* protect everything above... */
  96         struct mutex lock;
  97 };
  98
  99 struct ipath_user_sdma_queue *
 100 ipath_user_sdma_queue_create(struct device *dev, int unit, int port, int sport)
 101 {
 102         struct ipath_user_sdma_queue *pq =
 103                 kmalloc(sizeof(struct ipath_user_sdma_queue), GFP_KERNEL);
 104
 105         if (!pq)
 106                 goto done;
 107
 108         pq->counter = 0;
 109         pq->sent_counter = 0;
 110         INIT_LIST_HEAD(&pq->sent);
 111
 112         mutex_init(&pq->lock);
 113
 114         snprintf(pq->pkt_slab_name, sizeof(pq->pkt_slab_name),
 115                  "ipath-user-sdma-pkts-%u-%02u.%02u", unit, port, sport);
 116         pq->pkt_slab = kmem_cache_create(pq->pkt_slab_name,
 117                                          sizeof(struct ipath_user_sdma_pkt),
 118                                          0, 0, NULL);
 119
 120         if (!pq->pkt_slab)
 121                 goto err_kfree;
 122
 123         snprintf(pq->header_cache_name, sizeof(pq->header_cache_name),
 124                  "ipath-user-sdma-headers-%u-%02u.%02u", unit, port, sport);
 125         pq->header_cache = dma_pool_create(pq->header_cache_name,
 126                                            dev,
 127                                            IPATH_USER_SDMA_EXP_HEADER_LENGTH,
 128                                            4, 0);
 129         if (!pq->header_cache)
 130                 goto err_slab;
 131
 132         pq->dma_pages_root = RB_ROOT;
 133
 134         goto done;
 135
 136 err_slab:
 137         kmem_cache_destroy(pq->pkt_slab);
 138 err_kfree:
 139         kfree(pq);
 140         pq = NULL;
 141
 142 done:
 143         return pq;
 144 }
 145
 146 static void ipath_user_sdma_init_frag(struct ipath_user_sdma_pkt *pkt,
 147                                       int i, size_t offset, size_t len,
 148                                       int put_page, int dma_mapped,
 149                                       struct page *page,
 150                                       void *kvaddr, dma_addr_t dma_addr)
 151 {
 152         pkt->addr[i].offset = offset;
 153         pkt->addr[i].length = len;
 154         pkt->addr[i].put_page = put_page;
 155         pkt->addr[i].dma_mapped = dma_mapped;
 156         pkt->addr[i].page = page;
 157         pkt->addr[i].kvaddr = kvaddr;
 158         pkt->addr[i].addr = dma_addr;
 159 }
 160
 161 static void ipath_user_sdma_init_header(struct ipath_user_sdma_pkt *pkt,
 162                                         u32 counter, size_t offset,
 163                                         size_t len, int dma_mapped,
 164                                         struct page *page,
 165                                         void *kvaddr, dma_addr_t dma_addr)
 166 {
 167         pkt->naddr = 1;
 168         pkt->counter = counter;
 169         ipath_user_sdma_init_frag(pkt, 0, offset, len, 0, dma_mapped, page,
 170                                   kvaddr, dma_addr);
 171 }
 172
 173 /* we've too many pages in the iovec, coalesce to a single page */
 174 static int ipath_user_sdma_coalesce(const struct ipath_devdata *dd,
 175                                     struct ipath_user_sdma_pkt *pkt,
 176                                     const struct iovec *iov,
 177                                     unsigned long niov) {
 178         int ret = 0;
 179         struct page *page = alloc_page(GFP_KERNEL);
 180         void *mpage_save;
 181         char *mpage;
 182         int i;
 183         int len = 0;
 184         dma_addr_t dma_addr;
 185
 186         if (!page) {
 187                 ret = -ENOMEM;
 188                 goto done;
 189         }
 190
 191         mpage = kmap(page);
 192         mpage_save = mpage;
 193         for (i = 0; i < niov; i++) {
 194                 int cfur;
 195
 196                 cfur = copy_from_user(mpage,
 197                                       iov[i].iov_base, iov[i].iov_len);
 198                 if (cfur) {
 199                         ret = -EFAULT;
 200                         goto free_unmap;
 201                 }
 202
 203                 mpage += iov[i].iov_len;
 204                 len += iov[i].iov_len;
 205         }
 206
 207         dma_addr = dma_map_page(&dd->pcidev->dev, page, 0, len,
 208                                 DMA_TO_DEVICE);
 209         if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) {
 210                 ret = -ENOMEM;
 211                 goto free_unmap;
 212         }
 213
 214         ipath_user_sdma_init_frag(pkt, 1, 0, len, 0, 1, page, mpage_save,
 215                                   dma_addr);
 216         pkt->naddr = 2;
 217
 218         goto done;
 219
 220 free_unmap:
 221         kunmap(page);
 222         __free_page(page);
 223 done:
 224         return ret;
 225 }
 226
 227 /* how many pages in this iovec element? */
 228 static int ipath_user_sdma_num_pages(const struct iovec *iov)
 229 {
 230         const unsigned long addr  = (unsigned long) iov->iov_base;
 231         const unsigned long  len  = iov->iov_len;
 232         const unsigned long spage = addr & PAGE_MASK;
 233         const unsigned long epage = (addr + len - 1) & PAGE_MASK;
 234
 235         return 1 + ((epage - spage) >> PAGE_SHIFT);
 236 }
 237
 238 /* truncate length to page boundary */
 239 static int ipath_user_sdma_page_length(unsigned long addr, unsigned long len)
 240 {
 241         const unsigned long offset = offset_in_page(addr);
 242
 243         return ((offset + len) > PAGE_SIZE) ? (PAGE_SIZE - offset) : len;
 244 }
 245
 246 static void ipath_user_sdma_free_pkt_frag(struct device *dev,
 247                                           struct ipath_user_sdma_queue *pq,
 248                                           struct ipath_user_sdma_pkt *pkt,
 249                                           int frag)
 250 {
 251         const int i = frag;
 252
 253         if (pkt->addr[i].page) {
 254                 if (pkt->addr[i].dma_mapped)
 255                         dma_unmap_page(dev,
 256                                        pkt->addr[i].addr,
 257                                        pkt->addr[i].length,
 258                                        DMA_TO_DEVICE);
 259
 260                 if (pkt->addr[i].kvaddr)
 261                         kunmap(pkt->addr[i].page);
 262
 263                 if (pkt->addr[i].put_page)
 264                         put_page(pkt->addr[i].page);
 265                 else
 266                         __free_page(pkt->addr[i].page);
 267         } else if (pkt->addr[i].kvaddr)
 268                 /* free coherent mem from cache... */
 269                 dma_pool_free(pq->header_cache,
 270                               pkt->addr[i].kvaddr, pkt->addr[i].addr);
 271 }
 272
 273 /* return number of pages pinned... */
 274 static int ipath_user_sdma_pin_pages(const struct ipath_devdata *dd,
 275                                      struct ipath_user_sdma_pkt *pkt,
 276                                      unsigned long addr, int tlen, int npages)
 277 {
 278         struct page *pages[2];
 279         int j;
 280         int ret;
 281
 282         ret = get_user_pages_fast(addr, npages, 0, pages);
 283         if (ret != npages) {
 284                 int i;
 285
 286                 for (i = 0; i < ret; i++)
 287                         put_page(pages[i]);
 288
 289                 ret = -ENOMEM;
 290                 goto done;
 291         }
 292
 293         for (j = 0; j < npages; j++) {
 294                 /* map the pages... */
 295                 const int flen =
 296                         ipath_user_sdma_page_length(addr, tlen);
 297                 dma_addr_t dma_addr =
 298                         dma_map_page(&dd->pcidev->dev,
 299                                      pages[j], 0, flen, DMA_TO_DEVICE);
 300                 unsigned long fofs = offset_in_page(addr);
 301
 302                 if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) {
 303                         ret = -ENOMEM;
 304                         goto done;
 305                 }
 306
 307                 ipath_user_sdma_init_frag(pkt, pkt->naddr, fofs, flen, 1, 1,
 308                                           pages[j], kmap(pages[j]),
 309                                           dma_addr);
 310
 311                 pkt->naddr++;
 312                 addr += flen;
 313                 tlen -= flen;
 314         }
 315
 316 done:
 317         return ret;
 318 }
 319
 320 static int ipath_user_sdma_pin_pkt(const struct ipath_devdata *dd,
 321                                    struct ipath_user_sdma_queue *pq,
 322                                    struct ipath_user_sdma_pkt *pkt,
 323                                    const struct iovec *iov,
 324                                    unsigned long niov)
 325 {
 326         int ret = 0;
 327         unsigned long idx;
 328
 329         for (idx = 0; idx < niov; idx++) {
 330                 const int npages = ipath_user_sdma_num_pages(iov + idx);
 331                 const unsigned long addr = (unsigned long) iov[idx].iov_base;
 332
 333                 ret = ipath_user_sdma_pin_pages(dd, pkt,
 334                                                 addr, iov[idx].iov_len,
 335                                                 npages);
 336                 if (ret < 0)
 337                         goto free_pkt;
 338         }
 339
 340         goto done;
 341
 342 free_pkt:
 343         for (idx = 0; idx < pkt->naddr; idx++)
 344                 ipath_user_sdma_free_pkt_frag(&dd->pcidev->dev, pq, pkt, idx);
 345
 346 done:
 347         return ret;
 348 }
 349
 350 static int ipath_user_sdma_init_payload(const struct ipath_devdata *dd,
 351                                         struct ipath_user_sdma_queue *pq,
 352                                         struct ipath_user_sdma_pkt *pkt,
 353                                         const struct iovec *iov,
 354                                         unsigned long niov, int npages)
 355 {
 356         int ret = 0;
 357
 358         if (npages >= ARRAY_SIZE(pkt->addr))
 359                 ret = ipath_user_sdma_coalesce(dd, pkt, iov, niov);
 360         else
 361                 ret = ipath_user_sdma_pin_pkt(dd, pq, pkt, iov, niov);
 362
 363         return ret;
 364 }
 365
 366 /* free a packet list -- return counter value of last packet */
 367 static void ipath_user_sdma_free_pkt_list(struct device *dev,
 368                                           struct ipath_user_sdma_queue *pq,
 369                                           struct list_head *list)
 370 {
 371         struct ipath_user_sdma_pkt *pkt, *pkt_next;
 372
 373         list_for_each_entry_safe(pkt, pkt_next, list, list) {
 374                 int i;
 375
 376                 for (i = 0; i < pkt->naddr; i++)
 377                         ipath_user_sdma_free_pkt_frag(dev, pq, pkt, i);
 378
 379                 kmem_cache_free(pq->pkt_slab, pkt);
 380         }
 381 }
 382
 383 /*
 384  * copy headers, coalesce etc -- pq->lock must be held
 385  *
 386  * we queue all the packets to list, returning the
 387  * number of bytes total.  list must be empty initially,
 388  * as, if there is an error we clean it...
 389  */
 390 static int ipath_user_sdma_queue_pkts(const struct ipath_devdata *dd,
 391                                       struct ipath_user_sdma_queue *pq,
 392                                       struct list_head *list,
 393                                       const struct iovec *iov,
 394                                       unsigned long niov,
 395                                       int maxpkts)
 396 {
 397         unsigned long idx = 0;
 398         int ret = 0;
 399         int npkts = 0;
 400         struct page *page = NULL;
 401         __le32 *pbc;
 402         dma_addr_t dma_addr;
 403         struct ipath_user_sdma_pkt *pkt = NULL;
 404         size_t len;
 405         size_t nw;
 406         u32 counter = pq->counter;
 407         int dma_mapped = 0;
 408
 409         while (idx < niov && npkts < maxpkts) {
 410                 const unsigned long addr = (unsigned long) iov[idx].iov_base;
 411                 const unsigned long idx_save = idx;
 412                 unsigned pktnw;
 413                 unsigned pktnwc;
 414                 int nfrags = 0;
 415                 int npages = 0;
 416                 int cfur;
 417
 418                 dma_mapped = 0;
 419                 len = iov[idx].iov_len;
 420                 nw = len >> 2;
 421                 page = NULL;
 422
 423                 pkt = kmem_cache_alloc(pq->pkt_slab, GFP_KERNEL);
 424                 if (!pkt) {
 425                         ret = -ENOMEM;
 426                         goto free_list;
 427                 }
 428
 429                 if (len < IPATH_USER_SDMA_MIN_HEADER_LENGTH ||
 430                     len > PAGE_SIZE || len & 3 || addr & 3) {
 431                         ret = -EINVAL;
 432                         goto free_pkt;
 433                 }
 434
 435                 if (len == IPATH_USER_SDMA_EXP_HEADER_LENGTH)
 436                         pbc = dma_pool_alloc(pq->header_cache, GFP_KERNEL,
 437                                              &dma_addr);
 438                 else
 439                         pbc = NULL;
 440
 441                 if (!pbc) {
 442                         page = alloc_page(GFP_KERNEL);
 443                         if (!page) {
 444                                 ret = -ENOMEM;
 445                                 goto free_pkt;
 446                         }
 447                         pbc = kmap(page);
 448                 }
 449
 450                 cfur = copy_from_user(pbc, iov[idx].iov_base, len);
 451                 if (cfur) {
 452                         ret = -EFAULT;
 453                         goto free_pbc;
 454                 }
 455
 456                 /*
 457                  * this assignment is a bit strange.  it's because the
 458                  * the pbc counts the number of 32 bit words in the full
 459                  * packet _except_ the first word of the pbc itself...
 460                  */
 461                 pktnwc = nw - 1;
 462
 463                 /*
 464                  * pktnw computation yields the number of 32 bit words
 465                  * that the caller has indicated in the PBC.  note that
 466                  * this is one less than the total number of words that
 467                  * goes to the send DMA engine as the first 32 bit word
 468                  * of the PBC itself is not counted.  Armed with this count,
 469                  * we can verify that the packet is consistent with the
 470                  * iovec lengths.
 471                  */
 472                 pktnw = le32_to_cpu(*pbc) & IPATH_PBC_LENGTH_MASK;
 473                 if (pktnw < pktnwc || pktnw > pktnwc + (PAGE_SIZE >> 2)) {
 474                         ret = -EINVAL;
 475                         goto free_pbc;
 476                 }
 477
 478
 479                 idx++;
 480                 while (pktnwc < pktnw && idx < niov) {
 481                         const size_t slen = iov[idx].iov_len;
 482                         const unsigned long faddr =
 483                                 (unsigned long) iov[idx].iov_base;
 484
 485                         if (slen & 3 || faddr & 3 || !slen ||
 486                             slen > PAGE_SIZE) {
 487                                 ret = -EINVAL;
 488                                 goto free_pbc;
 489                         }
 490
 491                         npages++;
 492                         if ((faddr & PAGE_MASK) !=
 493                             ((faddr + slen - 1) & PAGE_MASK))
 494                                 npages++;
 495
 496                         pktnwc += slen >> 2;
 497                         idx++;
 498                         nfrags++;
 499                 }
 500
 501                 if (pktnwc != pktnw) {
 502                         ret = -EINVAL;
 503                         goto free_pbc;
 504                 }
 505
 506                 if (page) {
 507                         dma_addr = dma_map_page(&dd->pcidev->dev,
 508                                                 page, 0, len, DMA_TO_DEVICE);
 509                         if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) {
 510                                 ret = -ENOMEM;
 511                                 goto free_pbc;
 512                         }
 513
 514                         dma_mapped = 1;
 515                 }
 516
 517                 ipath_user_sdma_init_header(pkt, counter, 0, len, dma_mapped,
 518                                             page, pbc, dma_addr);
 519
 520                 if (nfrags) {
 521                         ret = ipath_user_sdma_init_payload(dd, pq, pkt,
 522                                                            iov + idx_save + 1,
 523                                                            nfrags, npages);
 524                         if (ret < 0)
 525                                 goto free_pbc_dma;
 526                 }
 527
 528                 counter++;
 529                 npkts++;
 530
 531                 list_add_tail(&pkt->list, list);
 532         }
 533
 534         ret = idx;
 535         goto done;
 536
 537 free_pbc_dma:
 538         if (dma_mapped)
 539                 dma_unmap_page(&dd->pcidev->dev, dma_addr, len, DMA_TO_DEVICE);
 540 free_pbc:
 541         if (page) {
 542                 kunmap(page);
 543                 __free_page(page);
 544         } else
 545                 dma_pool_free(pq->header_cache, pbc, dma_addr);
 546 free_pkt:
 547         kmem_cache_free(pq->pkt_slab, pkt);
 548 free_list:
 549         ipath_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, list);
 550 done:
 551         return ret;
 552 }
 553
 554 static void ipath_user_sdma_set_complete_counter(struct ipath_user_sdma_queue *pq,
 555                                                  u32 c)
 556 {
 557         pq->sent_counter = c;
 558 }
 559
 560 /* try to clean out queue -- needs pq->lock */
 561 static int ipath_user_sdma_queue_clean(const struct ipath_devdata *dd,
 562                                        struct ipath_user_sdma_queue *pq)
 563 {
 564         struct list_head free_list;
 565         struct ipath_user_sdma_pkt *pkt;
 566         struct ipath_user_sdma_pkt *pkt_prev;
 567         int ret = 0;
 568
 569         INIT_LIST_HEAD(&free_list);
 570
 571         list_for_each_entry_safe(pkt, pkt_prev, &pq->sent, list) {
 572                 s64 descd = dd->ipath_sdma_descq_removed - pkt->added;
 573
 574                 if (descd < 0)
 575                         break;
 576
 577                 list_move_tail(&pkt->list, &free_list);
 578
 579                 /* one more packet cleaned */
 580                 ret++;
 581         }
 582
 583         if (!list_empty(&free_list)) {
 584                 u32 counter;
 585
 586                 pkt = list_entry(free_list.prev,
 587                                  struct ipath_user_sdma_pkt, list);
 588                 counter = pkt->counter;
 589
 590                 ipath_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
 591                 ipath_user_sdma_set_complete_counter(pq, counter);
 592         }
 593
 594         return ret;
 595 }
 596
 597 void ipath_user_sdma_queue_destroy(struct ipath_user_sdma_queue *pq)
 598 {
 599         if (!pq)
 600                 return;
 601
 602         kmem_cache_destroy(pq->pkt_slab);
 603         dma_pool_destroy(pq->header_cache);
 604         kfree(pq);
 605 }
 606
 607 /* clean descriptor queue, returns > 0 if some elements cleaned */
 608 static int ipath_user_sdma_hwqueue_clean(struct ipath_devdata *dd)
 609 {
 610         int ret;
 611         unsigned long flags;
 612
 613         spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
 614         ret = ipath_sdma_make_progress(dd);
 615         spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
 616
 617         return ret;
 618 }
 619
 620 /* we're in close, drain packets so that we can cleanup successfully... */
 621 void ipath_user_sdma_queue_drain(struct ipath_devdata *dd,
 622                                  struct ipath_user_sdma_queue *pq)
 623 {
 624         int i;
 625
 626         if (!pq)
 627                 return;
 628
 629         for (i = 0; i < 100; i++) {
 630                 mutex_lock(&pq->lock);
 631                 if (list_empty(&pq->sent)) {
 632                         mutex_unlock(&pq->lock);
 633                         break;
 634                 }
 635                 ipath_user_sdma_hwqueue_clean(dd);
 636                 ipath_user_sdma_queue_clean(dd, pq);
 637                 mutex_unlock(&pq->lock);
 638                 msleep(10);
 639         }
 640
 641         if (!list_empty(&pq->sent)) {
 642                 struct list_head free_list;
 643
 644                 printk(KERN_INFO "drain: lists not empty: forcing!\n");
 645                 INIT_LIST_HEAD(&free_list);
 646                 mutex_lock(&pq->lock);
 647                 list_splice_init(&pq->sent, &free_list);
 648                 ipath_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
 649                 mutex_unlock(&pq->lock);
 650         }
 651 }
 652
 653 static inline __le64 ipath_sdma_make_desc0(struct ipath_devdata *dd,
 654                                            u64 addr, u64 dwlen, u64 dwoffset)
 655 {
 656         return cpu_to_le64(/* SDmaPhyAddr[31:0] */
 657                            ((addr & 0xfffffffcULL) << 32) |
 658                            /* SDmaGeneration[1:0] */
 659                            ((dd->ipath_sdma_generation & 3ULL) << 30) |
 660                            /* SDmaDwordCount[10:0] */
 661                            ((dwlen & 0x7ffULL) << 16) |
 662                            /* SDmaBufOffset[12:2] */
 663                            (dwoffset & 0x7ffULL));
 664 }
 665
 666 static inline __le64 ipath_sdma_make_first_desc0(__le64 descq)
 667 {
 668         return descq | cpu_to_le64(1ULL << 12);
 669 }
 670
 671 static inline __le64 ipath_sdma_make_last_desc0(__le64 descq)
 672 {
 673                                               /* last */  /* dma head */
 674         return descq | cpu_to_le64(1ULL << 11 | 1ULL << 13);
 675 }
 676
 677 static inline __le64 ipath_sdma_make_desc1(u64 addr)
 678 {
 679         /* SDmaPhyAddr[47:32] */
 680         return cpu_to_le64(addr >> 32);
 681 }
 682
 683 static void ipath_user_sdma_send_frag(struct ipath_devdata *dd,
 684                                       struct ipath_user_sdma_pkt *pkt, int idx,
 685                                       unsigned ofs, u16 tail)
 686 {
 687         const u64 addr = (u64) pkt->addr[idx].addr +
 688                 (u64) pkt->addr[idx].offset;
 689         const u64 dwlen = (u64) pkt->addr[idx].length / 4;
 690         __le64 *descqp;
 691         __le64 descq0;
 692
 693         descqp = &dd->ipath_sdma_descq[tail].qw[0];
 694
 695         descq0 = ipath_sdma_make_desc0(dd, addr, dwlen, ofs);
 696         if (idx == 0)
 697                 descq0 = ipath_sdma_make_first_desc0(descq0);
 698         if (idx == pkt->naddr - 1)
 699                 descq0 = ipath_sdma_make_last_desc0(descq0);
 700
 701         descqp[0] = descq0;
 702         descqp[1] = ipath_sdma_make_desc1(addr);
 703 }
 704
 705 /* pq->lock must be held, get packets on the wire... */
 706 static int ipath_user_sdma_push_pkts(struct ipath_devdata *dd,
 707                                      struct ipath_user_sdma_queue *pq,
 708                                      struct list_head *pktlist)
 709 {
 710         int ret = 0;
 711         unsigned long flags;
 712         u16 tail;
 713
 714         if (list_empty(pktlist))
 715                 return 0;
 716
 717         if (unlikely(!(dd->ipath_flags & IPATH_LINKACTIVE)))
 718                 return -ECOMM;
 719
 720         spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
 721
 722         if (unlikely(dd->ipath_sdma_status & IPATH_SDMA_ABORT_MASK)) {
 723                 ret = -ECOMM;
 724                 goto unlock;
 725         }
 726
 727         tail = dd->ipath_sdma_descq_tail;
 728         while (!list_empty(pktlist)) {
 729                 struct ipath_user_sdma_pkt *pkt =
 730                         list_entry(pktlist->next, struct ipath_user_sdma_pkt,
 731                                    list);
 732                 int i;
 733                 unsigned ofs = 0;
 734                 u16 dtail = tail;
 735
 736                 if (pkt->naddr > ipath_sdma_descq_freecnt(dd))
 737                         goto unlock_check_tail;
 738
 739                 for (i = 0; i < pkt->naddr; i++) {
 740                         ipath_user_sdma_send_frag(dd, pkt, i, ofs, tail);
 741                         ofs += pkt->addr[i].length >> 2;
 742
 743                         if (++tail == dd->ipath_sdma_descq_cnt) {
 744                                 tail = 0;
 745                                 ++dd->ipath_sdma_generation;
 746                         }
 747                 }
 748
 749                 if ((ofs<<2) > dd->ipath_ibmaxlen) {
 750                         ipath_dbg("packet size %X > ibmax %X, fail\n",
 751                                 ofs<<2, dd->ipath_ibmaxlen);
 752                         ret = -EMSGSIZE;
 753                         goto unlock;
 754                 }
 755
 756                 /*
 757                  * if the packet is >= 2KB mtu equivalent, we have to use
 758                  * the large buffers, and have to mark each descriptor as
 759                  * part of a large buffer packet.
 760                  */
 761                 if (ofs >= IPATH_SMALLBUF_DWORDS) {
 762                         for (i = 0; i < pkt->naddr; i++) {
 763                                 dd->ipath_sdma_descq[dtail].qw[0] |=
 764                                         cpu_to_le64(1ULL << 14);
 765                                 if (++dtail == dd->ipath_sdma_descq_cnt)
 766                                         dtail = 0;
 767                         }
 768                 }
 769
 770                 dd->ipath_sdma_descq_added += pkt->naddr;
 771                 pkt->added = dd->ipath_sdma_descq_added;
 772                 list_move_tail(&pkt->list, &pq->sent);
 773                 ret++;
 774         }
 775
 776 unlock_check_tail:
 777         /* advance the tail on the chip if necessary */
 778         if (dd->ipath_sdma_descq_tail != tail) {
 779                 wmb();
 780                 ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmatail, tail);
 781                 dd->ipath_sdma_descq_tail = tail;
 782         }
 783
 784 unlock:
 785         spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
 786
 787         return ret;
 788 }
 789
 790 int ipath_user_sdma_writev(struct ipath_devdata *dd,
 791                            struct ipath_user_sdma_queue *pq,
 792                            const struct iovec *iov,
 793                            unsigned long dim)
 794 {
 795         int ret = 0;
 796         struct list_head list;
 797         int npkts = 0;
 798
 799         INIT_LIST_HEAD(&list);
 800
 801         mutex_lock(&pq->lock);
 802
 803         if (dd->ipath_sdma_descq_added != dd->ipath_sdma_descq_removed) {
 804                 ipath_user_sdma_hwqueue_clean(dd);
 805                 ipath_user_sdma_queue_clean(dd, pq);
 806         }
 807
 808         while (dim) {
 809                 const int mxp = 8;
 810
 811                 ret = ipath_user_sdma_queue_pkts(dd, pq, &list, iov, dim, mxp);
 812                 if (ret <= 0)
 813                         goto done_unlock;
 814                 else {
 815                         dim -= ret;
 816                         iov += ret;
 817                 }
 818
 819                 /* force packets onto the sdma hw queue... */
 820                 if (!list_empty(&list)) {
 821                         /*
 822                          * lazily clean hw queue.  the 4 is a guess of about
 823                          * how many sdma descriptors a packet will take (it
 824                          * doesn't have to be perfect).
 825                          */
 826                         if (ipath_sdma_descq_freecnt(dd) < ret * 4) {
 827                                 ipath_user_sdma_hwqueue_clean(dd);
 828                                 ipath_user_sdma_queue_clean(dd, pq);
 829                         }
 830
 831                         ret = ipath_user_sdma_push_pkts(dd, pq, &list);
 832                         if (ret < 0)
 833                                 goto done_unlock;
 834                         else {
 835                                 npkts += ret;
 836                                 pq->counter += ret;
 837
 838                                 if (!list_empty(&list))
 839                                         goto done_unlock;
 840                         }
 841                 }
 842         }
 843
 844 done_unlock:
 845         if (!list_empty(&list))
 846                 ipath_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &list);
 847         mutex_unlock(&pq->lock);
 848
 849         return (ret < 0) ? ret : npkts;
 850 }
 851
 852 int ipath_user_sdma_make_progress(struct ipath_devdata *dd,
 853                                   struct ipath_user_sdma_queue *pq)
 854 {
 855         int ret = 0;
 856
 857         mutex_lock(&pq->lock);
 858         ipath_user_sdma_hwqueue_clean(dd);
 859         ret = ipath_user_sdma_queue_clean(dd, pq);
 860         mutex_unlock(&pq->lock);
 861
 862         return ret;
 863 }
 864
 865 u32 ipath_user_sdma_complete_counter(const struct ipath_user_sdma_queue *pq)
 866 {
 867         return pq->sent_counter;
 868 }
 869
 870 u32 ipath_user_sdma_inflight_counter(struct ipath_user_sdma_queue *pq)
 871 {
 872         return pq->counter;
 873 }
 874