root/drivers/infiniband/hw/qib/qib_file_ops.c

DEFINITIONS

1. cvt_kvaddr
2. qib_get_base_info
3. qib_tid_update
4. qib_tid_free
5. qib_set_part_key
6. qib_manage_rcvq
7. qib_clean_part_key
8. qib_mmap_mem
9. mmap_ureg
10. mmap_piobufs
11. mmap_rcvegrbufs
12. qib_file_vma_fault
13. mmap_kvaddr
14. qib_mmapf
15. qib_poll_urgent
16. qib_poll_next
17. qib_poll
18. assign_ctxt_affinity
19. qib_compatible_subctxts
20. init_subctxts
21. setup_ctxt
22. usable
23. choose_port_ctxt
24. find_free_ctxt
25. get_a_ctxt
26. find_shared_ctxt
27. qib_open
28. find_hca
29. do_qib_user_sdma_queue_create
30. qib_assign_ctxt
31. qib_do_user_init
32. unlock_expected_tids
33. qib_close
34. qib_ctxt_info
35. qib_sdma_get_inflight
36. qib_sdma_get_complete
37. disarm_req_delay
38. qib_set_uevent_bits
39. qib_user_event_ack
40. qib_write
41. qib_write_iter
42. qib_cdev_init
43. qib_cdev_cleanup
44. qib_dev_init
45. qib_dev_cleanup
46. qib_user_remove
47. qib_user_add
48. qib_device_create
49. qib_device_remove

   1 /*
   2  * Copyright (c) 2012, 2013 Intel Corporation. All rights reserved.
   3  * Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
   4  * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
   5  *
   6  * This software is available to you under a choice of one of two
   7  * licenses.  You may choose to be licensed under the terms of the GNU
   8  * General Public License (GPL) Version 2, available from the file
   9  * COPYING in the main directory of this source tree, or the
  10  * OpenIB.org BSD license below:
  11  *
  12  *     Redistribution and use in source and binary forms, with or
  13  *     without modification, are permitted provided that the following
  14  *     conditions are met:
  15  *
  16  *      - Redistributions of source code must retain the above
  17  *        copyright notice, this list of conditions and the following
  18  *        disclaimer.
  19  *
  20  *      - Redistributions in binary form must reproduce the above
  21  *        copyright notice, this list of conditions and the following
  22  *        disclaimer in the documentation and/or other materials
  23  *        provided with the distribution.
  24  *
  25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32  * SOFTWARE.
  33  */
  34 
  35 #include <linux/pci.h>
  36 #include <linux/poll.h>
  37 #include <linux/cdev.h>
  38 #include <linux/swap.h>
  39 #include <linux/vmalloc.h>
  40 #include <linux/highmem.h>
  41 #include <linux/io.h>
  42 #include <linux/jiffies.h>
  43 #include <asm/pgtable.h>
  44 #include <linux/delay.h>
  45 #include <linux/export.h>
  46 #include <linux/uio.h>
  47 
  48 #include <rdma/ib.h>
  49 
  50 #include "qib.h"
  51 #include "qib_common.h"
  52 #include "qib_user_sdma.h"
  53 
  54 #undef pr_fmt
  55 #define pr_fmt(fmt) QIB_DRV_NAME ": " fmt
  56 
  57 static int qib_open(struct inode *, struct file *);
  58 static int qib_close(struct inode *, struct file *);
  59 static ssize_t qib_write(struct file *, const char __user *, size_t, loff_t *);
  60 static ssize_t qib_write_iter(struct kiocb *, struct iov_iter *);
  61 static __poll_t qib_poll(struct file *, struct poll_table_struct *);
  62 static int qib_mmapf(struct file *, struct vm_area_struct *);
  63 
  64 /*
  65  * This is really, really weird shit - write() and writev() here
  66  * have completely unrelated semantics.  Sucky userland ABI,
  67  * film at 11.
  68  */
  69 static const struct file_operations qib_file_ops = {
  70         .owner = THIS_MODULE,
  71         .write = qib_write,
  72         .write_iter = qib_write_iter,
  73         .open = qib_open,
  74         .release = qib_close,
  75         .poll = qib_poll,
  76         .mmap = qib_mmapf,
  77         .llseek = noop_llseek,
  78 };
  79 
  80 /*
  81  * Convert kernel virtual addresses to physical addresses so they don't
  82  * potentially conflict with the chip addresses used as mmap offsets.
  83  * It doesn't really matter what mmap offset we use as long as we can
  84  * interpret it correctly.
  85  */
  86 static u64 cvt_kvaddr(void *p)
  87 {
  88         struct page *page;
  89         u64 paddr = 0;
  90 
  91         page = vmalloc_to_page(p);
  92         if (page)
  93                 paddr = page_to_pfn(page) << PAGE_SHIFT;
  94 
  95         return paddr;
  96 }
  97 
  98 static int qib_get_base_info(struct file *fp, void __user *ubase,
  99                              size_t ubase_size)
 100 {
 101         struct qib_ctxtdata *rcd = ctxt_fp(fp);
 102         int ret = 0;
 103         struct qib_base_info *kinfo = NULL;
 104         struct qib_devdata *dd = rcd->dd;
 105         struct qib_pportdata *ppd = rcd->ppd;
 106         unsigned subctxt_cnt;
 107         int shared, master;
 108         size_t sz;
 109 
 110         subctxt_cnt = rcd->subctxt_cnt;
 111         if (!subctxt_cnt) {
 112                 shared = 0;
 113                 master = 0;
 114                 subctxt_cnt = 1;
 115         } else {
 116                 shared = 1;
 117                 master = !subctxt_fp(fp);
 118         }
 119 
 120         sz = sizeof(*kinfo);
 121         /* If context sharing is not requested, allow the old size structure */
 122         if (!shared)
 123                 sz -= 7 * sizeof(u64);
 124         if (ubase_size < sz) {
 125                 ret = -EINVAL;
 126                 goto bail;
 127         }
 128 
 129         kinfo = kzalloc(sizeof(*kinfo), GFP_KERNEL);
 130         if (kinfo == NULL) {
 131                 ret = -ENOMEM;
 132                 goto bail;
 133         }
 134 
 135         ret = dd->f_get_base_info(rcd, kinfo);
 136         if (ret < 0)
 137                 goto bail;
 138 
 139         kinfo->spi_rcvhdr_cnt = dd->rcvhdrcnt;
 140         kinfo->spi_rcvhdrent_size = dd->rcvhdrentsize;
 141         kinfo->spi_tidegrcnt = rcd->rcvegrcnt;
 142         kinfo->spi_rcv_egrbufsize = dd->rcvegrbufsize;
 143         /*
 144          * have to mmap whole thing
 145          */
 146         kinfo->spi_rcv_egrbuftotlen =
 147                 rcd->rcvegrbuf_chunks * rcd->rcvegrbuf_size;
 148         kinfo->spi_rcv_egrperchunk = rcd->rcvegrbufs_perchunk;
 149         kinfo->spi_rcv_egrchunksize = kinfo->spi_rcv_egrbuftotlen /
 150                 rcd->rcvegrbuf_chunks;
 151         kinfo->spi_tidcnt = dd->rcvtidcnt / subctxt_cnt;
 152         if (master)
 153                 kinfo->spi_tidcnt += dd->rcvtidcnt % subctxt_cnt;
 154         /*
 155          * for this use, may be cfgctxts summed over all chips that
 156          * are are configured and present
 157          */
 158         kinfo->spi_nctxts = dd->cfgctxts;
 159         /* unit (chip/board) our context is on */
 160         kinfo->spi_unit = dd->unit;
 161         kinfo->spi_port = ppd->port;
 162         /* for now, only a single page */
 163         kinfo->spi_tid_maxsize = PAGE_SIZE;
 164 
 165         /*
 166          * Doing this per context, and based on the skip value, etc.  This has
 167          * to be the actual buffer size, since the protocol code treats it
 168          * as an array.
 169          *
 170          * These have to be set to user addresses in the user code via mmap.
 171          * These values are used on return to user code for the mmap target
 172          * addresses only.  For 32 bit, same 44 bit address problem, so use
 173          * the physical address, not virtual.  Before 2.6.11, using the
 174          * page_address() macro worked, but in 2.6.11, even that returns the
 175          * full 64 bit address (upper bits all 1's).  So far, using the
 176          * physical addresses (or chip offsets, for chip mapping) works, but
 177          * no doubt some future kernel release will change that, and we'll be
 178          * on to yet another method of dealing with this.
 179          * Normally only one of rcvhdr_tailaddr or rhf_offset is useful
 180          * since the chips with non-zero rhf_offset don't normally
 181          * enable tail register updates to host memory, but for testing,
 182          * both can be enabled and used.
 183          */
 184         kinfo->spi_rcvhdr_base = (u64) rcd->rcvhdrq_phys;
 185         kinfo->spi_rcvhdr_tailaddr = (u64) rcd->rcvhdrqtailaddr_phys;
 186         kinfo->spi_rhf_offset = dd->rhf_offset;
 187         kinfo->spi_rcv_egrbufs = (u64) rcd->rcvegr_phys;
 188         kinfo->spi_pioavailaddr = (u64) dd->pioavailregs_phys;
 189         /* setup per-unit (not port) status area for user programs */
 190         kinfo->spi_status = (u64) kinfo->spi_pioavailaddr +
 191                 (char *) ppd->statusp -
 192                 (char *) dd->pioavailregs_dma;
 193         kinfo->spi_uregbase = (u64) dd->uregbase + dd->ureg_align * rcd->ctxt;
 194         if (!shared) {
 195                 kinfo->spi_piocnt = rcd->piocnt;
 196                 kinfo->spi_piobufbase = (u64) rcd->piobufs;
 197                 kinfo->spi_sendbuf_status = cvt_kvaddr(rcd->user_event_mask);
 198         } else if (master) {
 199                 kinfo->spi_piocnt = (rcd->piocnt / subctxt_cnt) +
 200                                     (rcd->piocnt % subctxt_cnt);
 201                 /* Master's PIO buffers are after all the slave's */
 202                 kinfo->spi_piobufbase = (u64) rcd->piobufs +
 203                         dd->palign *
 204                         (rcd->piocnt - kinfo->spi_piocnt);
 205         } else {
 206                 unsigned slave = subctxt_fp(fp) - 1;
 207 
 208                 kinfo->spi_piocnt = rcd->piocnt / subctxt_cnt;
 209                 kinfo->spi_piobufbase = (u64) rcd->piobufs +
 210                         dd->palign * kinfo->spi_piocnt * slave;
 211         }
 212 
 213         if (shared) {
 214                 kinfo->spi_sendbuf_status =
 215                         cvt_kvaddr(&rcd->user_event_mask[subctxt_fp(fp)]);
 216                 /* only spi_subctxt_* fields should be set in this block! */
 217                 kinfo->spi_subctxt_uregbase = cvt_kvaddr(rcd->subctxt_uregbase);
 218 
 219                 kinfo->spi_subctxt_rcvegrbuf =
 220                         cvt_kvaddr(rcd->subctxt_rcvegrbuf);
 221                 kinfo->spi_subctxt_rcvhdr_base =
 222                         cvt_kvaddr(rcd->subctxt_rcvhdr_base);
 223         }
 224 
 225         /*
 226          * All user buffers are 2KB buffers.  If we ever support
 227          * giving 4KB buffers to user processes, this will need some
 228          * work.  Can't use piobufbase directly, because it has
 229          * both 2K and 4K buffer base values.
 230          */
 231         kinfo->spi_pioindex = (kinfo->spi_piobufbase - dd->pio2k_bufbase) /
 232                 dd->palign;
 233         kinfo->spi_pioalign = dd->palign;
 234         kinfo->spi_qpair = QIB_KD_QP;
 235         /*
 236          * user mode PIO buffers are always 2KB, even when 4KB can
 237          * be received, and sent via the kernel; this is ibmaxlen
 238          * for 2K MTU.
 239          */
 240         kinfo->spi_piosize = dd->piosize2k - 2 * sizeof(u32);
 241         kinfo->spi_mtu = ppd->ibmaxlen; /* maxlen, not ibmtu */
 242         kinfo->spi_ctxt = rcd->ctxt;
 243         kinfo->spi_subctxt = subctxt_fp(fp);
 244         kinfo->spi_sw_version = QIB_KERN_SWVERSION;
 245         kinfo->spi_sw_version |= 1U << 31; /* QLogic-built, not kernel.org */
 246         kinfo->spi_hw_version = dd->revision;
 247 
 248         if (master)
 249                 kinfo->spi_runtime_flags |= QIB_RUNTIME_MASTER;
 250 
 251         sz = (ubase_size < sizeof(*kinfo)) ? ubase_size : sizeof(*kinfo);
 252         if (copy_to_user(ubase, kinfo, sz))
 253                 ret = -EFAULT;
 254 bail:
 255         kfree(kinfo);
 256         return ret;
 257 }
 258 
 259 /**
 260  * qib_tid_update - update a context TID
 261  * @rcd: the context
 262  * @fp: the qib device file
 263  * @ti: the TID information
 264  *
 265  * The new implementation as of Oct 2004 is that the driver assigns
 266  * the tid and returns it to the caller.   To reduce search time, we
 267  * keep a cursor for each context, walking the shadow tid array to find
 268  * one that's not in use.
 269  *
 270  * For now, if we can't allocate the full list, we fail, although
 271  * in the long run, we'll allocate as many as we can, and the
 272  * caller will deal with that by trying the remaining pages later.
 273  * That means that when we fail, we have to mark the tids as not in
 274  * use again, in our shadow copy.
 275  *
 276  * It's up to the caller to free the tids when they are done.
 277  * We'll unlock the pages as they free them.
 278  *
 279  * Also, right now we are locking one page at a time, but since
 280  * the intended use of this routine is for a single group of
 281  * virtually contiguous pages, that should change to improve
 282  * performance.
 283  */
 284 static int qib_tid_update(struct qib_ctxtdata *rcd, struct file *fp,
 285                           const struct qib_tid_info *ti)
 286 {
 287         int ret = 0, ntids;
 288         u32 tid, ctxttid, cnt, i, tidcnt, tidoff;
 289         u16 *tidlist;
 290         struct qib_devdata *dd = rcd->dd;
 291         u64 physaddr;
 292         unsigned long vaddr;
 293         u64 __iomem *tidbase;
 294         unsigned long tidmap[8];
 295         struct page **pagep = NULL;
 296         unsigned subctxt = subctxt_fp(fp);
 297 
 298         if (!dd->pageshadow) {
 299                 ret = -ENOMEM;
 300                 goto done;
 301         }
 302 
 303         cnt = ti->tidcnt;
 304         if (!cnt) {
 305                 ret = -EFAULT;
 306                 goto done;
 307         }
 308         ctxttid = rcd->ctxt * dd->rcvtidcnt;
 309         if (!rcd->subctxt_cnt) {
 310                 tidcnt = dd->rcvtidcnt;
 311                 tid = rcd->tidcursor;
 312                 tidoff = 0;
 313         } else if (!subctxt) {
 314                 tidcnt = (dd->rcvtidcnt / rcd->subctxt_cnt) +
 315                          (dd->rcvtidcnt % rcd->subctxt_cnt);
 316                 tidoff = dd->rcvtidcnt - tidcnt;
 317                 ctxttid += tidoff;
 318                 tid = tidcursor_fp(fp);
 319         } else {
 320                 tidcnt = dd->rcvtidcnt / rcd->subctxt_cnt;
 321                 tidoff = tidcnt * (subctxt - 1);
 322                 ctxttid += tidoff;
 323                 tid = tidcursor_fp(fp);
 324         }
 325         if (cnt > tidcnt) {
 326                 /* make sure it all fits in tid_pg_list */
 327                 qib_devinfo(dd->pcidev,
 328                         "Process tried to allocate %u TIDs, only trying max (%u)\n",
 329                         cnt, tidcnt);
 330                 cnt = tidcnt;
 331         }
 332         pagep = (struct page **) rcd->tid_pg_list;
 333         tidlist = (u16 *) &pagep[dd->rcvtidcnt];
 334         pagep += tidoff;
 335         tidlist += tidoff;
 336 
 337         memset(tidmap, 0, sizeof(tidmap));
 338         /* before decrement; chip actual # */
 339         ntids = tidcnt;
 340         tidbase = (u64 __iomem *) (((char __iomem *) dd->kregbase) +
 341                                    dd->rcvtidbase +
 342                                    ctxttid * sizeof(*tidbase));
 343 
 344         /* virtual address of first page in transfer */
 345         vaddr = ti->tidvaddr;
 346         if (!access_ok((void __user *) vaddr,
 347                        cnt * PAGE_SIZE)) {
 348                 ret = -EFAULT;
 349                 goto done;
 350         }
 351         ret = qib_get_user_pages(vaddr, cnt, pagep);
 352         if (ret) {
 353                 /*
 354                  * if (ret == -EBUSY)
 355                  * We can't continue because the pagep array won't be
 356                  * initialized. This should never happen,
 357                  * unless perhaps the user has mpin'ed the pages
 358                  * themselves.
 359                  */
 360                 qib_devinfo(
 361                         dd->pcidev,
 362                         "Failed to lock addr %p, %u pages: errno %d\n",
 363                         (void *) vaddr, cnt, -ret);
 364                 goto done;
 365         }
 366         for (i = 0; i < cnt; i++, vaddr += PAGE_SIZE) {
 367                 dma_addr_t daddr;
 368 
 369                 for (; ntids--; tid++) {
 370                         if (tid == tidcnt)
 371                                 tid = 0;
 372                         if (!dd->pageshadow[ctxttid + tid])
 373                                 break;
 374                 }
 375                 if (ntids < 0) {
 376                         /*
 377                          * Oops, wrapped all the way through their TIDs,
 378                          * and didn't have enough free; see comments at
 379                          * start of routine
 380                          */
 381                         i--;    /* last tidlist[i] not filled in */
 382                         ret = -ENOMEM;
 383                         break;
 384                 }
 385                 ret = qib_map_page(dd->pcidev, pagep[i], &daddr);
 386                 if (ret)
 387                         break;
 388 
 389                 tidlist[i] = tid + tidoff;
 390                 /* we "know" system pages and TID pages are same size */
 391                 dd->pageshadow[ctxttid + tid] = pagep[i];
 392                 dd->physshadow[ctxttid + tid] = daddr;
 393                 /*
 394                  * don't need atomic or it's overhead
 395                  */
 396                 __set_bit(tid, tidmap);
 397                 physaddr = dd->physshadow[ctxttid + tid];
 398                 /* PERFORMANCE: below should almost certainly be cached */
 399                 dd->f_put_tid(dd, &tidbase[tid],
 400                                   RCVHQ_RCV_TYPE_EXPECTED, physaddr);
 401                 /*
 402                  * don't check this tid in qib_ctxtshadow, since we
 403                  * just filled it in; start with the next one.
 404                  */
 405                 tid++;
 406         }
 407 
 408         if (ret) {
 409                 u32 limit;
 410 cleanup:
 411                 /* jump here if copy out of updated info failed... */
 412                 /* same code that's in qib_free_tid() */
 413                 limit = sizeof(tidmap) * BITS_PER_BYTE;
 414                 if (limit > tidcnt)
 415                         /* just in case size changes in future */
 416                         limit = tidcnt;
 417                 tid = find_first_bit((const unsigned long *)tidmap, limit);
 418                 for (; tid < limit; tid++) {
 419                         if (!test_bit(tid, tidmap))
 420                                 continue;
 421                         if (dd->pageshadow[ctxttid + tid]) {
 422                                 dma_addr_t phys;
 423 
 424                                 phys = dd->physshadow[ctxttid + tid];
 425                                 dd->physshadow[ctxttid + tid] = dd->tidinvalid;
 426                                 /* PERFORMANCE: below should almost certainly
 427                                  * be cached
 428                                  */
 429                                 dd->f_put_tid(dd, &tidbase[tid],
 430                                               RCVHQ_RCV_TYPE_EXPECTED,
 431                                               dd->tidinvalid);
 432                                 pci_unmap_page(dd->pcidev, phys, PAGE_SIZE,
 433                                                PCI_DMA_FROMDEVICE);
 434                                 dd->pageshadow[ctxttid + tid] = NULL;
 435                         }
 436                 }
 437                 qib_release_user_pages(pagep, cnt);
 438         } else {
 439                 /*
 440                  * Copy the updated array, with qib_tid's filled in, back
 441                  * to user.  Since we did the copy in already, this "should
 442                  * never fail" If it does, we have to clean up...
 443                  */
 444                 if (copy_to_user((void __user *)
 445                                  (unsigned long) ti->tidlist,
 446                                  tidlist, cnt * sizeof(*tidlist))) {
 447                         ret = -EFAULT;
 448                         goto cleanup;
 449                 }
 450                 if (copy_to_user(u64_to_user_ptr(ti->tidmap),
 451                                  tidmap, sizeof(tidmap))) {
 452                         ret = -EFAULT;
 453                         goto cleanup;
 454                 }
 455                 if (tid == tidcnt)
 456                         tid = 0;
 457                 if (!rcd->subctxt_cnt)
 458                         rcd->tidcursor = tid;
 459                 else
 460                         tidcursor_fp(fp) = tid;
 461         }
 462 
 463 done:
 464         return ret;
 465 }
 466 
 467 /**
 468  * qib_tid_free - free a context TID
 469  * @rcd: the context
 470  * @subctxt: the subcontext
 471  * @ti: the TID info
 472  *
 473  * right now we are unlocking one page at a time, but since
 474  * the intended use of this routine is for a single group of
 475  * virtually contiguous pages, that should change to improve
 476  * performance.  We check that the TID is in range for this context
 477  * but otherwise don't check validity; if user has an error and
 478  * frees the wrong tid, it's only their own data that can thereby
 479  * be corrupted.  We do check that the TID was in use, for sanity
 480  * We always use our idea of the saved address, not the address that
 481  * they pass in to us.
 482  */
 483 static int qib_tid_free(struct qib_ctxtdata *rcd, unsigned subctxt,
 484                         const struct qib_tid_info *ti)
 485 {
 486         int ret = 0;
 487         u32 tid, ctxttid, cnt, limit, tidcnt;
 488         struct qib_devdata *dd = rcd->dd;
 489         u64 __iomem *tidbase;
 490         unsigned long tidmap[8];
 491 
 492         if (!dd->pageshadow) {
 493                 ret = -ENOMEM;
 494                 goto done;
 495         }
 496 
 497         if (copy_from_user(tidmap, u64_to_user_ptr(ti->tidmap),
 498                            sizeof(tidmap))) {
 499                 ret = -EFAULT;
 500                 goto done;
 501         }
 502 
 503         ctxttid = rcd->ctxt * dd->rcvtidcnt;
 504         if (!rcd->subctxt_cnt)
 505                 tidcnt = dd->rcvtidcnt;
 506         else if (!subctxt) {
 507                 tidcnt = (dd->rcvtidcnt / rcd->subctxt_cnt) +
 508                          (dd->rcvtidcnt % rcd->subctxt_cnt);
 509                 ctxttid += dd->rcvtidcnt - tidcnt;
 510         } else {
 511                 tidcnt = dd->rcvtidcnt / rcd->subctxt_cnt;
 512                 ctxttid += tidcnt * (subctxt - 1);
 513         }
 514         tidbase = (u64 __iomem *) ((char __iomem *)(dd->kregbase) +
 515                                    dd->rcvtidbase +
 516                                    ctxttid * sizeof(*tidbase));
 517 
 518         limit = sizeof(tidmap) * BITS_PER_BYTE;
 519         if (limit > tidcnt)
 520                 /* just in case size changes in future */
 521                 limit = tidcnt;
 522         tid = find_first_bit(tidmap, limit);
 523         for (cnt = 0; tid < limit; tid++) {
 524                 /*
 525                  * small optimization; if we detect a run of 3 or so without
 526                  * any set, use find_first_bit again.  That's mainly to
 527                  * accelerate the case where we wrapped, so we have some at
 528                  * the beginning, and some at the end, and a big gap
 529                  * in the middle.
 530                  */
 531                 if (!test_bit(tid, tidmap))
 532                         continue;
 533                 cnt++;
 534                 if (dd->pageshadow[ctxttid + tid]) {
 535                         struct page *p;
 536                         dma_addr_t phys;
 537 
 538                         p = dd->pageshadow[ctxttid + tid];
 539                         dd->pageshadow[ctxttid + tid] = NULL;
 540                         phys = dd->physshadow[ctxttid + tid];
 541                         dd->physshadow[ctxttid + tid] = dd->tidinvalid;
 542                         /* PERFORMANCE: below should almost certainly be
 543                          * cached
 544                          */
 545                         dd->f_put_tid(dd, &tidbase[tid],
 546                                       RCVHQ_RCV_TYPE_EXPECTED, dd->tidinvalid);
 547                         pci_unmap_page(dd->pcidev, phys, PAGE_SIZE,
 548                                        PCI_DMA_FROMDEVICE);
 549                         qib_release_user_pages(&p, 1);
 550                 }
 551         }
 552 done:
 553         return ret;
 554 }
 555 
 556 /**
 557  * qib_set_part_key - set a partition key
 558  * @rcd: the context
 559  * @key: the key
 560  *
 561  * We can have up to 4 active at a time (other than the default, which is
 562  * always allowed).  This is somewhat tricky, since multiple contexts may set
 563  * the same key, so we reference count them, and clean up at exit.  All 4
 564  * partition keys are packed into a single qlogic_ib register.  It's an
 565  * error for a process to set the same pkey multiple times.  We provide no
 566  * mechanism to de-allocate a pkey at this time, we may eventually need to
 567  * do that.  I've used the atomic operations, and no locking, and only make
 568  * a single pass through what's available.  This should be more than
 569  * adequate for some time. I'll think about spinlocks or the like if and as
 570  * it's necessary.
 571  */
 572 static int qib_set_part_key(struct qib_ctxtdata *rcd, u16 key)
 573 {
 574         struct qib_pportdata *ppd = rcd->ppd;
 575         int i, pidx = -1;
 576         bool any = false;
 577         u16 lkey = key & 0x7FFF;
 578 
 579         if (lkey == (QIB_DEFAULT_P_KEY & 0x7FFF))
 580                 /* nothing to do; this key always valid */
 581                 return 0;
 582 
 583         if (!lkey)
 584                 return -EINVAL;
 585 
 586         /*
 587          * Set the full membership bit, because it has to be
 588          * set in the register or the packet, and it seems
 589          * cleaner to set in the register than to force all
 590          * callers to set it.
 591          */
 592         key |= 0x8000;
 593 
 594         for (i = 0; i < ARRAY_SIZE(rcd->pkeys); i++) {
 595                 if (!rcd->pkeys[i] && pidx == -1)
 596                         pidx = i;
 597                 if (rcd->pkeys[i] == key)
 598                         return -EEXIST;
 599         }
 600         if (pidx == -1)
 601                 return -EBUSY;
 602         for (i = 0; i < ARRAY_SIZE(ppd->pkeys); i++) {
 603                 if (!ppd->pkeys[i]) {
 604                         any = true;
 605                         continue;
 606                 }
 607                 if (ppd->pkeys[i] == key) {
 608                         atomic_t *pkrefs = &ppd->pkeyrefs[i];
 609 
 610                         if (atomic_inc_return(pkrefs) > 1) {
 611                                 rcd->pkeys[pidx] = key;
 612                                 return 0;
 613                         }
 614                         /*
 615                          * lost race, decrement count, catch below
 616                          */
 617                         atomic_dec(pkrefs);
 618                         any = true;
 619                 }
 620                 if ((ppd->pkeys[i] & 0x7FFF) == lkey)
 621                         /*
 622                          * It makes no sense to have both the limited and
 623                          * full membership PKEY set at the same time since
 624                          * the unlimited one will disable the limited one.
 625                          */
 626                         return -EEXIST;
 627         }
 628         if (!any)
 629                 return -EBUSY;
 630         for (i = 0; i < ARRAY_SIZE(ppd->pkeys); i++) {
 631                 if (!ppd->pkeys[i] &&
 632                     atomic_inc_return(&ppd->pkeyrefs[i]) == 1) {
 633                         rcd->pkeys[pidx] = key;
 634                         ppd->pkeys[i] = key;
 635                         (void) ppd->dd->f_set_ib_cfg(ppd, QIB_IB_CFG_PKEYS, 0);
 636                         return 0;
 637                 }
 638         }
 639         return -EBUSY;
 640 }
 641 
 642 /**
 643  * qib_manage_rcvq - manage a context's receive queue
 644  * @rcd: the context
 645  * @subctxt: the subcontext
 646  * @start_stop: action to carry out
 647  *
 648  * start_stop == 0 disables receive on the context, for use in queue
 649  * overflow conditions.  start_stop==1 re-enables, to be used to
 650  * re-init the software copy of the head register
 651  */
 652 static int qib_manage_rcvq(struct qib_ctxtdata *rcd, unsigned subctxt,
 653                            int start_stop)
 654 {
 655         struct qib_devdata *dd = rcd->dd;
 656         unsigned int rcvctrl_op;
 657 
 658         if (subctxt)
 659                 goto bail;
 660         /* atomically clear receive enable ctxt. */
 661         if (start_stop) {
 662                 /*
 663                  * On enable, force in-memory copy of the tail register to
 664                  * 0, so that protocol code doesn't have to worry about
 665                  * whether or not the chip has yet updated the in-memory
 666                  * copy or not on return from the system call. The chip
 667                  * always resets it's tail register back to 0 on a
 668                  * transition from disabled to enabled.
 669                  */
 670                 if (rcd->rcvhdrtail_kvaddr)
 671                         qib_clear_rcvhdrtail(rcd);
 672                 rcvctrl_op = QIB_RCVCTRL_CTXT_ENB;
 673         } else
 674                 rcvctrl_op = QIB_RCVCTRL_CTXT_DIS;
 675         dd->f_rcvctrl(rcd->ppd, rcvctrl_op, rcd->ctxt);
 676         /* always; new head should be equal to new tail; see above */
 677 bail:
 678         return 0;
 679 }
 680 
 681 static void qib_clean_part_key(struct qib_ctxtdata *rcd,
 682                                struct qib_devdata *dd)
 683 {
 684         int i, j, pchanged = 0;
 685         struct qib_pportdata *ppd = rcd->ppd;
 686 
 687         for (i = 0; i < ARRAY_SIZE(rcd->pkeys); i++) {
 688                 if (!rcd->pkeys[i])
 689                         continue;
 690                 for (j = 0; j < ARRAY_SIZE(ppd->pkeys); j++) {
 691                         /* check for match independent of the global bit */
 692                         if ((ppd->pkeys[j] & 0x7fff) !=
 693                             (rcd->pkeys[i] & 0x7fff))
 694                                 continue;
 695                         if (atomic_dec_and_test(&ppd->pkeyrefs[j])) {
 696                                 ppd->pkeys[j] = 0;
 697                                 pchanged++;
 698                         }
 699                         break;
 700                 }
 701                 rcd->pkeys[i] = 0;
 702         }
 703         if (pchanged)
 704                 (void) ppd->dd->f_set_ib_cfg(ppd, QIB_IB_CFG_PKEYS, 0);
 705 }
 706 
 707 /* common code for the mappings on dma_alloc_coherent mem */
 708 static int qib_mmap_mem(struct vm_area_struct *vma, struct qib_ctxtdata *rcd,
 709                         unsigned len, void *kvaddr, u32 write_ok, char *what)
 710 {
 711         struct qib_devdata *dd = rcd->dd;
 712         unsigned long pfn;
 713         int ret;
 714 
 715         if ((vma->vm_end - vma->vm_start) > len) {
 716                 qib_devinfo(dd->pcidev,
 717                          "FAIL on %s: len %lx > %x\n", what,
 718                          vma->vm_end - vma->vm_start, len);
 719                 ret = -EFAULT;
 720                 goto bail;
 721         }
 722 
 723         /*
 724          * shared context user code requires rcvhdrq mapped r/w, others
 725          * only allowed readonly mapping.
 726          */
 727         if (!write_ok) {
 728                 if (vma->vm_flags & VM_WRITE) {
 729                         qib_devinfo(dd->pcidev,
 730                                  "%s must be mapped readonly\n", what);
 731                         ret = -EPERM;
 732                         goto bail;
 733                 }
 734 
 735                 /* don't allow them to later change with mprotect */
 736                 vma->vm_flags &= ~VM_MAYWRITE;
 737         }
 738 
 739         pfn = virt_to_phys(kvaddr) >> PAGE_SHIFT;
 740         ret = remap_pfn_range(vma, vma->vm_start, pfn,
 741                               len, vma->vm_page_prot);
 742         if (ret)
 743                 qib_devinfo(dd->pcidev,
 744                         "%s ctxt%u mmap of %lx, %x bytes failed: %d\n",
 745                         what, rcd->ctxt, pfn, len, ret);
 746 bail:
 747         return ret;
 748 }
 749 
 750 static int mmap_ureg(struct vm_area_struct *vma, struct qib_devdata *dd,
 751                      u64 ureg)
 752 {
 753         unsigned long phys;
 754         unsigned long sz;
 755         int ret;
 756 
 757         /*
 758          * This is real hardware, so use io_remap.  This is the mechanism
 759          * for the user process to update the head registers for their ctxt
 760          * in the chip.
 761          */
 762         sz = dd->flags & QIB_HAS_HDRSUPP ? 2 * PAGE_SIZE : PAGE_SIZE;
 763         if ((vma->vm_end - vma->vm_start) > sz) {
 764                 qib_devinfo(dd->pcidev,
 765                         "FAIL mmap userreg: reqlen %lx > PAGE\n",
 766                         vma->vm_end - vma->vm_start);
 767                 ret = -EFAULT;
 768         } else {
 769                 phys = dd->physaddr + ureg;
 770                 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 771 
 772                 vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;
 773                 ret = io_remap_pfn_range(vma, vma->vm_start,
 774                                          phys >> PAGE_SHIFT,
 775                                          vma->vm_end - vma->vm_start,
 776                                          vma->vm_page_prot);
 777         }
 778         return ret;
 779 }
 780 
 781 static int mmap_piobufs(struct vm_area_struct *vma,
 782                         struct qib_devdata *dd,
 783                         struct qib_ctxtdata *rcd,
 784                         unsigned piobufs, unsigned piocnt)
 785 {
 786         unsigned long phys;
 787         int ret;
 788 
 789         /*
 790          * When we map the PIO buffers in the chip, we want to map them as
 791          * writeonly, no read possible; unfortunately, x86 doesn't allow
 792          * for this in hardware, but we still prevent users from asking
 793          * for it.
 794          */
 795         if ((vma->vm_end - vma->vm_start) > (piocnt * dd->palign)) {
 796                 qib_devinfo(dd->pcidev,
 797                         "FAIL mmap piobufs: reqlen %lx > PAGE\n",
 798                          vma->vm_end - vma->vm_start);
 799                 ret = -EINVAL;
 800                 goto bail;
 801         }
 802 
 803         phys = dd->physaddr + piobufs;
 804 
 805 #if defined(__powerpc__)
 806         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 807 #endif
 808 
 809         /*
 810          * don't allow them to later change to readable with mprotect (for when
 811          * not initially mapped readable, as is normally the case)
 812          */
 813         vma->vm_flags &= ~VM_MAYREAD;
 814         vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;
 815 
 816         /* We used PAT if wc_cookie == 0 */
 817         if (!dd->wc_cookie)
 818                 vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
 819 
 820         ret = io_remap_pfn_range(vma, vma->vm_start, phys >> PAGE_SHIFT,
 821                                  vma->vm_end - vma->vm_start,
 822                                  vma->vm_page_prot);
 823 bail:
 824         return ret;
 825 }
 826 
 827 static int mmap_rcvegrbufs(struct vm_area_struct *vma,
 828                            struct qib_ctxtdata *rcd)
 829 {
 830         struct qib_devdata *dd = rcd->dd;
 831         unsigned long start, size;
 832         size_t total_size, i;
 833         unsigned long pfn;
 834         int ret;
 835 
 836         size = rcd->rcvegrbuf_size;
 837         total_size = rcd->rcvegrbuf_chunks * size;
 838         if ((vma->vm_end - vma->vm_start) > total_size) {
 839                 qib_devinfo(dd->pcidev,
 840                         "FAIL on egr bufs: reqlen %lx > actual %lx\n",
 841                          vma->vm_end - vma->vm_start,
 842                          (unsigned long) total_size);
 843                 ret = -EINVAL;
 844                 goto bail;
 845         }
 846 
 847         if (vma->vm_flags & VM_WRITE) {
 848                 qib_devinfo(dd->pcidev,
 849                         "Can't map eager buffers as writable (flags=%lx)\n",
 850                         vma->vm_flags);
 851                 ret = -EPERM;
 852                 goto bail;
 853         }
 854         /* don't allow them to later change to writeable with mprotect */
 855         vma->vm_flags &= ~VM_MAYWRITE;
 856 
 857         start = vma->vm_start;
 858 
 859         for (i = 0; i < rcd->rcvegrbuf_chunks; i++, start += size) {
 860                 pfn = virt_to_phys(rcd->rcvegrbuf[i]) >> PAGE_SHIFT;
 861                 ret = remap_pfn_range(vma, start, pfn, size,
 862                                       vma->vm_page_prot);
 863                 if (ret < 0)
 864                         goto bail;
 865         }
 866         ret = 0;
 867 
 868 bail:
 869         return ret;
 870 }
 871 
 872 /*
 873  * qib_file_vma_fault - handle a VMA page fault.
 874  */
 875 static vm_fault_t qib_file_vma_fault(struct vm_fault *vmf)
 876 {
 877         struct page *page;
 878 
 879         page = vmalloc_to_page((void *)(vmf->pgoff << PAGE_SHIFT));
 880         if (!page)
 881                 return VM_FAULT_SIGBUS;
 882 
 883         get_page(page);
 884         vmf->page = page;
 885 
 886         return 0;
 887 }
 888 
 889 static const struct vm_operations_struct qib_file_vm_ops = {
 890         .fault = qib_file_vma_fault,
 891 };
 892 
 893 static int mmap_kvaddr(struct vm_area_struct *vma, u64 pgaddr,
 894                        struct qib_ctxtdata *rcd, unsigned subctxt)
 895 {
 896         struct qib_devdata *dd = rcd->dd;
 897         unsigned subctxt_cnt;
 898         unsigned long len;
 899         void *addr;
 900         size_t size;
 901         int ret = 0;
 902 
 903         subctxt_cnt = rcd->subctxt_cnt;
 904         size = rcd->rcvegrbuf_chunks * rcd->rcvegrbuf_size;
 905 
 906         /*
 907          * Each process has all the subctxt uregbase, rcvhdrq, and
 908          * rcvegrbufs mmapped - as an array for all the processes,
 909          * and also separately for this process.
 910          */
 911         if (pgaddr == cvt_kvaddr(rcd->subctxt_uregbase)) {
 912                 addr = rcd->subctxt_uregbase;
 913                 size = PAGE_SIZE * subctxt_cnt;
 914         } else if (pgaddr == cvt_kvaddr(rcd->subctxt_rcvhdr_base)) {
 915                 addr = rcd->subctxt_rcvhdr_base;
 916                 size = rcd->rcvhdrq_size * subctxt_cnt;
 917         } else if (pgaddr == cvt_kvaddr(rcd->subctxt_rcvegrbuf)) {
 918                 addr = rcd->subctxt_rcvegrbuf;
 919                 size *= subctxt_cnt;
 920         } else if (pgaddr == cvt_kvaddr(rcd->subctxt_uregbase +
 921                                         PAGE_SIZE * subctxt)) {
 922                 addr = rcd->subctxt_uregbase + PAGE_SIZE * subctxt;
 923                 size = PAGE_SIZE;
 924         } else if (pgaddr == cvt_kvaddr(rcd->subctxt_rcvhdr_base +
 925                                         rcd->rcvhdrq_size * subctxt)) {
 926                 addr = rcd->subctxt_rcvhdr_base +
 927                         rcd->rcvhdrq_size * subctxt;
 928                 size = rcd->rcvhdrq_size;
 929         } else if (pgaddr == cvt_kvaddr(&rcd->user_event_mask[subctxt])) {
 930                 addr = rcd->user_event_mask;
 931                 size = PAGE_SIZE;
 932         } else if (pgaddr == cvt_kvaddr(rcd->subctxt_rcvegrbuf +
 933                                         size * subctxt)) {
 934                 addr = rcd->subctxt_rcvegrbuf + size * subctxt;
 935                 /* rcvegrbufs are read-only on the slave */
 936                 if (vma->vm_flags & VM_WRITE) {
 937                         qib_devinfo(dd->pcidev,
 938                                  "Can't map eager buffers as writable (flags=%lx)\n",
 939                                  vma->vm_flags);
 940                         ret = -EPERM;
 941                         goto bail;
 942                 }
 943                 /*
 944                  * Don't allow permission to later change to writeable
 945                  * with mprotect.
 946                  */
 947                 vma->vm_flags &= ~VM_MAYWRITE;
 948         } else
 949                 goto bail;
 950         len = vma->vm_end - vma->vm_start;
 951         if (len > size) {
 952                 ret = -EINVAL;
 953                 goto bail;
 954         }
 955 
 956         vma->vm_pgoff = (unsigned long) addr >> PAGE_SHIFT;
 957         vma->vm_ops = &qib_file_vm_ops;
 958         vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 959         ret = 1;
 960 
 961 bail:
 962         return ret;
 963 }
 964 
 965 /**
 966  * qib_mmapf - mmap various structures into user space
 967  * @fp: the file pointer
 968  * @vma: the VM area
 969  *
 970  * We use this to have a shared buffer between the kernel and the user code
 971  * for the rcvhdr queue, egr buffers, and the per-context user regs and pio
 972  * buffers in the chip.  We have the open and close entries so we can bump
 973  * the ref count and keep the driver from being unloaded while still mapped.
 974  */
 975 static int qib_mmapf(struct file *fp, struct vm_area_struct *vma)
 976 {
 977         struct qib_ctxtdata *rcd;
 978         struct qib_devdata *dd;
 979         u64 pgaddr, ureg;
 980         unsigned piobufs, piocnt;
 981         int ret, match = 1;
 982 
 983         rcd = ctxt_fp(fp);
 984         if (!rcd || !(vma->vm_flags & VM_SHARED)) {
 985                 ret = -EINVAL;
 986                 goto bail;
 987         }
 988         dd = rcd->dd;
 989 
 990         /*
 991          * This is the qib_do_user_init() code, mapping the shared buffers
 992          * and per-context user registers into the user process. The address
 993          * referred to by vm_pgoff is the file offset passed via mmap().
 994          * For shared contexts, this is the kernel vmalloc() address of the
 995          * pages to share with the master.
 996          * For non-shared or master ctxts, this is a physical address.
 997          * We only do one mmap for each space mapped.
 998          */
 999         pgaddr = vma->vm_pgoff << PAGE_SHIFT;
1000 
1001         /*
1002          * Check for 0 in case one of the allocations failed, but user
1003          * called mmap anyway.
1004          */
1005         if (!pgaddr)  {
1006                 ret = -EINVAL;
1007                 goto bail;
1008         }
1009 
1010         /*
1011          * Physical addresses must fit in 40 bits for our hardware.
1012          * Check for kernel virtual addresses first, anything else must
1013          * match a HW or memory address.
1014          */
1015         ret = mmap_kvaddr(vma, pgaddr, rcd, subctxt_fp(fp));
1016         if (ret) {
1017                 if (ret > 0)
1018                         ret = 0;
1019                 goto bail;
1020         }
1021 
1022         ureg = dd->uregbase + dd->ureg_align * rcd->ctxt;
1023         if (!rcd->subctxt_cnt) {
1024                 /* ctxt is not shared */
1025                 piocnt = rcd->piocnt;
1026                 piobufs = rcd->piobufs;
1027         } else if (!subctxt_fp(fp)) {
1028                 /* caller is the master */
1029                 piocnt = (rcd->piocnt / rcd->subctxt_cnt) +
1030                          (rcd->piocnt % rcd->subctxt_cnt);
1031                 piobufs = rcd->piobufs +
1032                         dd->palign * (rcd->piocnt - piocnt);
1033         } else {
1034                 unsigned slave = subctxt_fp(fp) - 1;
1035 
1036                 /* caller is a slave */
1037                 piocnt = rcd->piocnt / rcd->subctxt_cnt;
1038                 piobufs = rcd->piobufs + dd->palign * piocnt * slave;
1039         }
1040 
1041         if (pgaddr == ureg)
1042                 ret = mmap_ureg(vma, dd, ureg);
1043         else if (pgaddr == piobufs)
1044                 ret = mmap_piobufs(vma, dd, rcd, piobufs, piocnt);
1045         else if (pgaddr == dd->pioavailregs_phys)
1046                 /* in-memory copy of pioavail registers */
1047                 ret = qib_mmap_mem(vma, rcd, PAGE_SIZE,
1048                                    (void *) dd->pioavailregs_dma, 0,
1049                                    "pioavail registers");
1050         else if (pgaddr == rcd->rcvegr_phys)
1051                 ret = mmap_rcvegrbufs(vma, rcd);
1052         else if (pgaddr == (u64) rcd->rcvhdrq_phys)
1053                 /*
1054                  * The rcvhdrq itself; multiple pages, contiguous
1055                  * from an i/o perspective.  Shared contexts need
1056                  * to map r/w, so we allow writing.
1057                  */
1058                 ret = qib_mmap_mem(vma, rcd, rcd->rcvhdrq_size,
1059                                    rcd->rcvhdrq, 1, "rcvhdrq");
1060         else if (pgaddr == (u64) rcd->rcvhdrqtailaddr_phys)
1061                 /* in-memory copy of rcvhdrq tail register */
1062                 ret = qib_mmap_mem(vma, rcd, PAGE_SIZE,
1063                                    rcd->rcvhdrtail_kvaddr, 0,
1064                                    "rcvhdrq tail");
1065         else
1066                 match = 0;
1067         if (!match)
1068                 ret = -EINVAL;
1069 
1070         vma->vm_private_data = NULL;
1071 
1072         if (ret < 0)
1073                 qib_devinfo(dd->pcidev,
1074                          "mmap Failure %d: off %llx len %lx\n",
1075                          -ret, (unsigned long long)pgaddr,
1076                          vma->vm_end - vma->vm_start);
1077 bail:
1078         return ret;
1079 }
1080 
1081 static __poll_t qib_poll_urgent(struct qib_ctxtdata *rcd,
1082                                     struct file *fp,
1083                                     struct poll_table_struct *pt)
1084 {
1085         struct qib_devdata *dd = rcd->dd;
1086         __poll_t pollflag;
1087 
1088         poll_wait(fp, &rcd->wait, pt);
1089 
1090         spin_lock_irq(&dd->uctxt_lock);
1091         if (rcd->urgent != rcd->urgent_poll) {
1092                 pollflag = EPOLLIN | EPOLLRDNORM;
1093                 rcd->urgent_poll = rcd->urgent;
1094         } else {
1095                 pollflag = 0;
1096                 set_bit(QIB_CTXT_WAITING_URG, &rcd->flag);
1097         }
1098         spin_unlock_irq(&dd->uctxt_lock);
1099 
1100         return pollflag;
1101 }
1102 
1103 static __poll_t qib_poll_next(struct qib_ctxtdata *rcd,
1104                                   struct file *fp,
1105                                   struct poll_table_struct *pt)
1106 {
1107         struct qib_devdata *dd = rcd->dd;
1108         __poll_t pollflag;
1109 
1110         poll_wait(fp, &rcd->wait, pt);
1111 
1112         spin_lock_irq(&dd->uctxt_lock);
1113         if (dd->f_hdrqempty(rcd)) {
1114                 set_bit(QIB_CTXT_WAITING_RCV, &rcd->flag);
1115                 dd->f_rcvctrl(rcd->ppd, QIB_RCVCTRL_INTRAVAIL_ENB, rcd->ctxt);
1116                 pollflag = 0;
1117         } else
1118                 pollflag = EPOLLIN | EPOLLRDNORM;
1119         spin_unlock_irq(&dd->uctxt_lock);
1120 
1121         return pollflag;
1122 }
1123 
1124 static __poll_t qib_poll(struct file *fp, struct poll_table_struct *pt)
1125 {
1126         struct qib_ctxtdata *rcd;
1127         __poll_t pollflag;
1128 
1129         rcd = ctxt_fp(fp);
1130         if (!rcd)
1131                 pollflag = EPOLLERR;
1132         else if (rcd->poll_type == QIB_POLL_TYPE_URGENT)
1133                 pollflag = qib_poll_urgent(rcd, fp, pt);
1134         else  if (rcd->poll_type == QIB_POLL_TYPE_ANYRCV)
1135                 pollflag = qib_poll_next(rcd, fp, pt);
1136         else /* invalid */
1137                 pollflag = EPOLLERR;
1138 
1139         return pollflag;
1140 }
1141 
1142 static void assign_ctxt_affinity(struct file *fp, struct qib_devdata *dd)
1143 {
1144         struct qib_filedata *fd = fp->private_data;
1145         const unsigned int weight = current->nr_cpus_allowed;
1146         const struct cpumask *local_mask = cpumask_of_pcibus(dd->pcidev->bus);
1147         int local_cpu;
1148 
1149         /*
1150          * If process has NOT already set it's affinity, select and
1151          * reserve a processor for it on the local NUMA node.
1152          */
1153         if ((weight >= qib_cpulist_count) &&
1154                 (cpumask_weight(local_mask) <= qib_cpulist_count)) {
1155                 for_each_cpu(local_cpu, local_mask)
1156                         if (!test_and_set_bit(local_cpu, qib_cpulist)) {
1157                                 fd->rec_cpu_num = local_cpu;
1158                                 return;
1159                         }
1160         }
1161 
1162         /*
1163          * If process has NOT already set it's affinity, select and
1164          * reserve a processor for it, as a rendevous for all
1165          * users of the driver.  If they don't actually later
1166          * set affinity to this cpu, or set it to some other cpu,
1167          * it just means that sooner or later we don't recommend
1168          * a cpu, and let the scheduler do it's best.
1169          */
1170         if (weight >= qib_cpulist_count) {
1171                 int cpu;
1172 
1173                 cpu = find_first_zero_bit(qib_cpulist,
1174                                           qib_cpulist_count);
1175                 if (cpu == qib_cpulist_count)
1176                         qib_dev_err(dd,
1177                         "no cpus avail for affinity PID %u\n",
1178                         current->pid);
1179                 else {
1180                         __set_bit(cpu, qib_cpulist);
1181                         fd->rec_cpu_num = cpu;
1182                 }
1183         }
1184 }
1185 
1186 /*
1187  * Check that userland and driver are compatible for subcontexts.
1188  */
1189 static int qib_compatible_subctxts(int user_swmajor, int user_swminor)
1190 {
1191         /* this code is written long-hand for clarity */
1192         if (QIB_USER_SWMAJOR != user_swmajor) {
1193                 /* no promise of compatibility if major mismatch */
1194                 return 0;
1195         }
1196         if (QIB_USER_SWMAJOR == 1) {
1197                 switch (QIB_USER_SWMINOR) {
1198                 case 0:
1199                 case 1:
1200                 case 2:
1201                         /* no subctxt implementation so cannot be compatible */
1202                         return 0;
1203                 case 3:
1204                         /* 3 is only compatible with itself */
1205                         return user_swminor == 3;
1206                 default:
1207                         /* >= 4 are compatible (or are expected to be) */
1208                         return user_swminor <= QIB_USER_SWMINOR;
1209                 }
1210         }
1211         /* make no promises yet for future major versions */
1212         return 0;
1213 }
1214 
1215 static int init_subctxts(struct qib_devdata *dd,
1216                          struct qib_ctxtdata *rcd,
1217                          const struct qib_user_info *uinfo)
1218 {
1219         int ret = 0;
1220         unsigned num_subctxts;
1221         size_t size;
1222 
1223         /*
1224          * If the user is requesting zero subctxts,
1225          * skip the subctxt allocation.
1226          */
1227         if (uinfo->spu_subctxt_cnt <= 0)
1228                 goto bail;
1229         num_subctxts = uinfo->spu_subctxt_cnt;
1230 
1231         /* Check for subctxt compatibility */
1232         if (!qib_compatible_subctxts(uinfo->spu_userversion >> 16,
1233                 uinfo->spu_userversion & 0xffff)) {
1234                 qib_devinfo(dd->pcidev,
1235                          "Mismatched user version (%d.%d) and driver version (%d.%d) while context sharing. Ensure that driver and library are from the same release.\n",
1236                          (int) (uinfo->spu_userversion >> 16),
1237                          (int) (uinfo->spu_userversion & 0xffff),
1238                          QIB_USER_SWMAJOR, QIB_USER_SWMINOR);
1239                 goto bail;
1240         }
1241         if (num_subctxts > QLOGIC_IB_MAX_SUBCTXT) {
1242                 ret = -EINVAL;
1243                 goto bail;
1244         }
1245 
1246         rcd->subctxt_uregbase = vmalloc_user(PAGE_SIZE * num_subctxts);
1247         if (!rcd->subctxt_uregbase) {
1248                 ret = -ENOMEM;
1249                 goto bail;
1250         }
1251         /* Note: rcd->rcvhdrq_size isn't initialized yet. */
1252         size = ALIGN(dd->rcvhdrcnt * dd->rcvhdrentsize *
1253                      sizeof(u32), PAGE_SIZE) * num_subctxts;
1254         rcd->subctxt_rcvhdr_base = vmalloc_user(size);
1255         if (!rcd->subctxt_rcvhdr_base) {
1256                 ret = -ENOMEM;
1257                 goto bail_ureg;
1258         }
1259 
1260         rcd->subctxt_rcvegrbuf = vmalloc_user(rcd->rcvegrbuf_chunks *
1261                                               rcd->rcvegrbuf_size *
1262                                               num_subctxts);
1263         if (!rcd->subctxt_rcvegrbuf) {
1264                 ret = -ENOMEM;
1265                 goto bail_rhdr;
1266         }
1267 
1268         rcd->subctxt_cnt = uinfo->spu_subctxt_cnt;
1269         rcd->subctxt_id = uinfo->spu_subctxt_id;
1270         rcd->active_slaves = 1;
1271         rcd->redirect_seq_cnt = 1;
1272         set_bit(QIB_CTXT_MASTER_UNINIT, &rcd->flag);
1273         goto bail;
1274 
1275 bail_rhdr:
1276         vfree(rcd->subctxt_rcvhdr_base);
1277 bail_ureg:
1278         vfree(rcd->subctxt_uregbase);
1279         rcd->subctxt_uregbase = NULL;
1280 bail:
1281         return ret;
1282 }
1283 
1284 static int setup_ctxt(struct qib_pportdata *ppd, int ctxt,
1285                       struct file *fp, const struct qib_user_info *uinfo)
1286 {
1287         struct qib_filedata *fd = fp->private_data;
1288         struct qib_devdata *dd = ppd->dd;
1289         struct qib_ctxtdata *rcd;
1290         void *ptmp = NULL;
1291         int ret;
1292         int numa_id;
1293 
1294         assign_ctxt_affinity(fp, dd);
1295 
1296         numa_id = qib_numa_aware ? ((fd->rec_cpu_num != -1) ?
1297                 cpu_to_node(fd->rec_cpu_num) :
1298                 numa_node_id()) : dd->assigned_node_id;
1299 
1300         rcd = qib_create_ctxtdata(ppd, ctxt, numa_id);
1301 
1302         /*
1303          * Allocate memory for use in qib_tid_update() at open to
1304          * reduce cost of expected send setup per message segment
1305          */
1306         if (rcd)
1307                 ptmp = kmalloc(dd->rcvtidcnt * sizeof(u16) +
1308                                dd->rcvtidcnt * sizeof(struct page **),
1309                                GFP_KERNEL);
1310 
1311         if (!rcd || !ptmp) {
1312                 qib_dev_err(dd,
1313                         "Unable to allocate ctxtdata memory, failing open\n");
1314                 ret = -ENOMEM;
1315                 goto bailerr;
1316         }
1317         rcd->userversion = uinfo->spu_userversion;
1318         ret = init_subctxts(dd, rcd, uinfo);
1319         if (ret)
1320                 goto bailerr;
1321         rcd->tid_pg_list = ptmp;
1322         rcd->pid = current->pid;
1323         init_waitqueue_head(&dd->rcd[ctxt]->wait);
1324         strlcpy(rcd->comm, current->comm, sizeof(rcd->comm));
1325         ctxt_fp(fp) = rcd;
1326         qib_stats.sps_ctxts++;
1327         dd->freectxts--;
1328         ret = 0;
1329         goto bail;
1330 
1331 bailerr:
1332         if (fd->rec_cpu_num != -1)
1333                 __clear_bit(fd->rec_cpu_num, qib_cpulist);
1334 
1335         dd->rcd[ctxt] = NULL;
1336         kfree(rcd);
1337         kfree(ptmp);
1338 bail:
1339         return ret;
1340 }
1341 
1342 static inline int usable(struct qib_pportdata *ppd)
1343 {
1344         struct qib_devdata *dd = ppd->dd;
1345 
1346         return dd && (dd->flags & QIB_PRESENT) && dd->kregbase && ppd->lid &&
1347                 (ppd->lflags & QIBL_LINKACTIVE);
1348 }
1349 
1350 /*
1351  * Select a context on the given device, either using a requested port
1352  * or the port based on the context number.
1353  */
1354 static int choose_port_ctxt(struct file *fp, struct qib_devdata *dd, u32 port,
1355                             const struct qib_user_info *uinfo)
1356 {
1357         struct qib_pportdata *ppd = NULL;
1358         int ret, ctxt;
1359 
1360         if (port) {
1361                 if (!usable(dd->pport + port - 1)) {
1362                         ret = -ENETDOWN;
1363                         goto done;
1364                 } else
1365                         ppd = dd->pport + port - 1;
1366         }
1367         for (ctxt = dd->first_user_ctxt; ctxt < dd->cfgctxts && dd->rcd[ctxt];
1368              ctxt++)
1369                 ;
1370         if (ctxt == dd->cfgctxts) {
1371                 ret = -EBUSY;
1372                 goto done;
1373         }
1374         if (!ppd) {
1375                 u32 pidx = ctxt % dd->num_pports;
1376 
1377                 if (usable(dd->pport + pidx))
1378                         ppd = dd->pport + pidx;
1379                 else {
1380                         for (pidx = 0; pidx < dd->num_pports && !ppd;
1381                              pidx++)
1382                                 if (usable(dd->pport + pidx))
1383                                         ppd = dd->pport + pidx;
1384                 }
1385         }
1386         ret = ppd ? setup_ctxt(ppd, ctxt, fp, uinfo) : -ENETDOWN;
1387 done:
1388         return ret;
1389 }
1390 
1391 static int find_free_ctxt(int unit, struct file *fp,
1392                           const struct qib_user_info *uinfo)
1393 {
1394         struct qib_devdata *dd = qib_lookup(unit);
1395         int ret;
1396 
1397         if (!dd || (uinfo->spu_port && uinfo->spu_port > dd->num_pports))
1398                 ret = -ENODEV;
1399         else
1400                 ret = choose_port_ctxt(fp, dd, uinfo->spu_port, uinfo);
1401 
1402         return ret;
1403 }
1404 
1405 static int get_a_ctxt(struct file *fp, const struct qib_user_info *uinfo,
1406                       unsigned alg)
1407 {
1408         struct qib_devdata *udd = NULL;
1409         int ret = 0, devmax, npresent, nup, ndev, dusable = 0, i;
1410         u32 port = uinfo->spu_port, ctxt;
1411 
1412         devmax = qib_count_units(&npresent, &nup);
1413         if (!npresent) {
1414                 ret = -ENXIO;
1415                 goto done;
1416         }
1417         if (nup == 0) {
1418                 ret = -ENETDOWN;
1419                 goto done;
1420         }
1421 
1422         if (alg == QIB_PORT_ALG_ACROSS) {
1423                 unsigned inuse = ~0U;
1424 
1425                 /* find device (with ACTIVE ports) with fewest ctxts in use */
1426                 for (ndev = 0; ndev < devmax; ndev++) {
1427                         struct qib_devdata *dd = qib_lookup(ndev);
1428                         unsigned cused = 0, cfree = 0, pusable = 0;
1429 
1430                         if (!dd)
1431                                 continue;
1432                         if (port && port <= dd->num_pports &&
1433                             usable(dd->pport + port - 1))
1434                                 pusable = 1;
1435                         else
1436                                 for (i = 0; i < dd->num_pports; i++)
1437                                         if (usable(dd->pport + i))
1438                                                 pusable++;
1439                         if (!pusable)
1440                                 continue;
1441                         for (ctxt = dd->first_user_ctxt; ctxt < dd->cfgctxts;
1442                              ctxt++)
1443                                 if (dd->rcd[ctxt])
1444                                         cused++;
1445                                 else
1446                                         cfree++;
1447                         if (cfree && cused < inuse) {
1448                                 udd = dd;
1449                                 inuse = cused;
1450                         }
1451                 }
1452                 if (udd) {
1453                         ret = choose_port_ctxt(fp, udd, port, uinfo);
1454                         goto done;
1455                 }
1456         } else {
1457                 for (ndev = 0; ndev < devmax; ndev++) {
1458                         struct qib_devdata *dd = qib_lookup(ndev);
1459 
1460                         if (dd) {
1461                                 ret = choose_port_ctxt(fp, dd, port, uinfo);
1462                                 if (!ret)
1463                                         goto done;
1464                                 if (ret == -EBUSY)
1465                                         dusable++;
1466                         }
1467                 }
1468         }
1469         ret = dusable ? -EBUSY : -ENETDOWN;
1470 
1471 done:
1472         return ret;
1473 }
1474 
1475 static int find_shared_ctxt(struct file *fp,
1476                             const struct qib_user_info *uinfo)
1477 {
1478         int devmax, ndev, i;
1479         int ret = 0;
1480 
1481         devmax = qib_count_units(NULL, NULL);
1482 
1483         for (ndev = 0; ndev < devmax; ndev++) {
1484                 struct qib_devdata *dd = qib_lookup(ndev);
1485 
1486                 /* device portion of usable() */
1487                 if (!(dd && (dd->flags & QIB_PRESENT) && dd->kregbase))
1488                         continue;
1489                 for (i = dd->first_user_ctxt; i < dd->cfgctxts; i++) {
1490                         struct qib_ctxtdata *rcd = dd->rcd[i];
1491 
1492                         /* Skip ctxts which are not yet open */
1493                         if (!rcd || !rcd->cnt)
1494                                 continue;
1495                         /* Skip ctxt if it doesn't match the requested one */
1496                         if (rcd->subctxt_id != uinfo->spu_subctxt_id)
1497                                 continue;
1498                         /* Verify the sharing process matches the master */
1499                         if (rcd->subctxt_cnt != uinfo->spu_subctxt_cnt ||
1500                             rcd->userversion != uinfo->spu_userversion ||
1501                             rcd->cnt >= rcd->subctxt_cnt) {
1502                                 ret = -EINVAL;
1503                                 goto done;
1504                         }
1505                         ctxt_fp(fp) = rcd;
1506                         subctxt_fp(fp) = rcd->cnt++;
1507                         rcd->subpid[subctxt_fp(fp)] = current->pid;
1508                         tidcursor_fp(fp) = 0;
1509                         rcd->active_slaves |= 1 << subctxt_fp(fp);
1510                         ret = 1;
1511                         goto done;
1512                 }
1513         }
1514 
1515 done:
1516         return ret;
1517 }
1518 
1519 static int qib_open(struct inode *in, struct file *fp)
1520 {
1521         /* The real work is performed later in qib_assign_ctxt() */
1522         fp->private_data = kzalloc(sizeof(struct qib_filedata), GFP_KERNEL);
1523         if (fp->private_data) /* no cpu affinity by default */
1524                 ((struct qib_filedata *)fp->private_data)->rec_cpu_num = -1;
1525         return fp->private_data ? 0 : -ENOMEM;
1526 }
1527 
1528 static int find_hca(unsigned int cpu, int *unit)
1529 {
1530         int ret = 0, devmax, npresent, nup, ndev;
1531 
1532         *unit = -1;
1533 
1534         devmax = qib_count_units(&npresent, &nup);
1535         if (!npresent) {
1536                 ret = -ENXIO;
1537                 goto done;
1538         }
1539         if (!nup) {
1540                 ret = -ENETDOWN;
1541                 goto done;
1542         }
1543         for (ndev = 0; ndev < devmax; ndev++) {
1544                 struct qib_devdata *dd = qib_lookup(ndev);
1545 
1546                 if (dd) {
1547                         if (pcibus_to_node(dd->pcidev->bus) < 0) {
1548                                 ret = -EINVAL;
1549                                 goto done;
1550                         }
1551                         if (cpu_to_node(cpu) ==
1552                                 pcibus_to_node(dd->pcidev->bus)) {
1553                                 *unit = ndev;
1554                                 goto done;
1555                         }
1556                 }
1557         }
1558 done:
1559         return ret;
1560 }
1561 
1562 static int do_qib_user_sdma_queue_create(struct file *fp)
1563 {
1564         struct qib_filedata *fd = fp->private_data;
1565         struct qib_ctxtdata *rcd = fd->rcd;
1566         struct qib_devdata *dd = rcd->dd;
1567 
1568         if (dd->flags & QIB_HAS_SEND_DMA) {
1569 
1570                 fd->pq = qib_user_sdma_queue_create(&dd->pcidev->dev,
1571                                                     dd->unit,
1572                                                     rcd->ctxt,
1573                                                     fd->subctxt);
1574                 if (!fd->pq)
1575                         return -ENOMEM;
1576         }
1577 
1578         return 0;
1579 }
1580 
1581 /*
1582  * Get ctxt early, so can set affinity prior to memory allocation.
1583  */
1584 static int qib_assign_ctxt(struct file *fp, const struct qib_user_info *uinfo)
1585 {
1586         int ret;
1587         int i_minor;
1588         unsigned swmajor, swminor, alg = QIB_PORT_ALG_ACROSS;
1589 
1590         /* Check to be sure we haven't already initialized this file */
1591         if (ctxt_fp(fp)) {
1592                 ret = -EINVAL;
1593                 goto done;
1594         }
1595 
1596         /* for now, if major version is different, bail */
1597         swmajor = uinfo->spu_userversion >> 16;
1598         if (swmajor != QIB_USER_SWMAJOR) {
1599                 ret = -ENODEV;
1600                 goto done;
1601         }
1602 
1603         swminor = uinfo->spu_userversion & 0xffff;
1604 
1605         if (swminor >= 11 && uinfo->spu_port_alg < QIB_PORT_ALG_COUNT)
1606                 alg = uinfo->spu_port_alg;
1607 
1608         mutex_lock(&qib_mutex);
1609 
1610         if (qib_compatible_subctxts(swmajor, swminor) &&
1611             uinfo->spu_subctxt_cnt) {
1612                 ret = find_shared_ctxt(fp, uinfo);
1613                 if (ret > 0) {
1614                         ret = do_qib_user_sdma_queue_create(fp);
1615                         if (!ret)
1616                                 assign_ctxt_affinity(fp, (ctxt_fp(fp))->dd);
1617                         goto done_ok;
1618                 }
1619         }
1620 
1621         i_minor = iminor(file_inode(fp)) - QIB_USER_MINOR_BASE;
1622         if (i_minor)
1623                 ret = find_free_ctxt(i_minor - 1, fp, uinfo);
1624         else {
1625                 int unit;
1626                 const unsigned int cpu = cpumask_first(current->cpus_ptr);
1627                 const unsigned int weight = current->nr_cpus_allowed;
1628 
1629                 if (weight == 1 && !test_bit(cpu, qib_cpulist))
1630                         if (!find_hca(cpu, &unit) && unit >= 0)
1631                                 if (!find_free_ctxt(unit, fp, uinfo)) {
1632                                         ret = 0;
1633                                         goto done_chk_sdma;
1634                                 }
1635                 ret = get_a_ctxt(fp, uinfo, alg);
1636         }
1637 
1638 done_chk_sdma:
1639         if (!ret)
1640                 ret = do_qib_user_sdma_queue_create(fp);
1641 done_ok:
1642         mutex_unlock(&qib_mutex);
1643 
1644 done:
1645         return ret;
1646 }
1647 
1648 
1649 static int qib_do_user_init(struct file *fp,
1650                             const struct qib_user_info *uinfo)
1651 {
1652         int ret;
1653         struct qib_ctxtdata *rcd = ctxt_fp(fp);
1654         struct qib_devdata *dd;
1655         unsigned uctxt;
1656 
1657         /* Subctxts don't need to initialize anything since master did it. */
1658         if (subctxt_fp(fp)) {
1659                 ret = wait_event_interruptible(rcd->wait,
1660                         !test_bit(QIB_CTXT_MASTER_UNINIT, &rcd->flag));
1661                 goto bail;
1662         }
1663 
1664         dd = rcd->dd;
1665 
1666         /* some ctxts may get extra buffers, calculate that here */
1667         uctxt = rcd->ctxt - dd->first_user_ctxt;
1668         if (uctxt < dd->ctxts_extrabuf) {
1669                 rcd->piocnt = dd->pbufsctxt + 1;
1670                 rcd->pio_base = rcd->piocnt * uctxt;
1671         } else {
1672                 rcd->piocnt = dd->pbufsctxt;
1673                 rcd->pio_base = rcd->piocnt * uctxt +
1674                         dd->ctxts_extrabuf;
1675         }
1676 
1677         /*
1678          * All user buffers are 2KB buffers.  If we ever support
1679          * giving 4KB buffers to user processes, this will need some
1680          * work.  Can't use piobufbase directly, because it has
1681          * both 2K and 4K buffer base values.  So check and handle.
1682          */
1683         if ((rcd->pio_base + rcd->piocnt) > dd->piobcnt2k) {
1684                 if (rcd->pio_base >= dd->piobcnt2k) {
1685                         qib_dev_err(dd,
1686                                     "%u:ctxt%u: no 2KB buffers available\n",
1687                                     dd->unit, rcd->ctxt);
1688                         ret = -ENOBUFS;
1689                         goto bail;
1690                 }
1691                 rcd->piocnt = dd->piobcnt2k - rcd->pio_base;
1692                 qib_dev_err(dd, "Ctxt%u: would use 4KB bufs, using %u\n",
1693                             rcd->ctxt, rcd->piocnt);
1694         }
1695 
1696         rcd->piobufs = dd->pio2k_bufbase + rcd->pio_base * dd->palign;
1697         qib_chg_pioavailkernel(dd, rcd->pio_base, rcd->piocnt,
1698                                TXCHK_CHG_TYPE_USER, rcd);
1699         /*
1700          * try to ensure that processes start up with consistent avail update
1701          * for their own range, at least.   If system very quiet, it might
1702          * have the in-memory copy out of date at startup for this range of
1703          * buffers, when a context gets re-used.  Do after the chg_pioavail
1704          * and before the rest of setup, so it's "almost certain" the dma
1705          * will have occurred (can't 100% guarantee, but should be many
1706          * decimals of 9s, with this ordering), given how much else happens
1707          * after this.
1708          */
1709         dd->f_sendctrl(dd->pport, QIB_SENDCTRL_AVAIL_BLIP);
1710 
1711         /*
1712          * Now allocate the rcvhdr Q and eager TIDs; skip the TID
1713          * array for time being.  If rcd->ctxt > chip-supported,
1714          * we need to do extra stuff here to handle by handling overflow
1715          * through ctxt 0, someday
1716          */
1717         ret = qib_create_rcvhdrq(dd, rcd);
1718         if (!ret)
1719                 ret = qib_setup_eagerbufs(rcd);
1720         if (ret)
1721                 goto bail_pio;
1722 
1723         rcd->tidcursor = 0; /* start at beginning after open */
1724 
1725         /* initialize poll variables... */
1726         rcd->urgent = 0;
1727         rcd->urgent_poll = 0;
1728 
1729         /*
1730          * Now enable the ctxt for receive.
1731          * For chips that are set to DMA the tail register to memory
1732          * when they change (and when the update bit transitions from
1733          * 0 to 1.  So for those chips, we turn it off and then back on.
1734          * This will (very briefly) affect any other open ctxts, but the
1735          * duration is very short, and therefore isn't an issue.  We
1736          * explicitly set the in-memory tail copy to 0 beforehand, so we
1737          * don't have to wait to be sure the DMA update has happened
1738          * (chip resets head/tail to 0 on transition to enable).
1739          */
1740         if (rcd->rcvhdrtail_kvaddr)
1741                 qib_clear_rcvhdrtail(rcd);
1742 
1743         dd->f_rcvctrl(rcd->ppd, QIB_RCVCTRL_CTXT_ENB | QIB_RCVCTRL_TIDFLOW_ENB,
1744                       rcd->ctxt);
1745 
1746         /* Notify any waiting slaves */
1747         if (rcd->subctxt_cnt) {
1748                 clear_bit(QIB_CTXT_MASTER_UNINIT, &rcd->flag);
1749                 wake_up(&rcd->wait);
1750         }
1751         return 0;
1752 
1753 bail_pio:
1754         qib_chg_pioavailkernel(dd, rcd->pio_base, rcd->piocnt,
1755                                TXCHK_CHG_TYPE_KERN, rcd);
1756 bail:
1757         return ret;
1758 }
1759 
1760 /**
1761  * unlock_exptid - unlock any expected TID entries context still had in use
1762  * @rcd: ctxt
1763  *
1764  * We don't actually update the chip here, because we do a bulk update
1765  * below, using f_clear_tids.
1766  */
1767 static void unlock_expected_tids(struct qib_ctxtdata *rcd)
1768 {
1769         struct qib_devdata *dd = rcd->dd;
1770         int ctxt_tidbase = rcd->ctxt * dd->rcvtidcnt;
1771         int i, cnt = 0, maxtid = ctxt_tidbase + dd->rcvtidcnt;
1772 
1773         for (i = ctxt_tidbase; i < maxtid; i++) {
1774                 struct page *p = dd->pageshadow[i];
1775                 dma_addr_t phys;
1776 
1777                 if (!p)
1778                         continue;
1779 
1780                 phys = dd->physshadow[i];
1781                 dd->physshadow[i] = dd->tidinvalid;
1782                 dd->pageshadow[i] = NULL;
1783                 pci_unmap_page(dd->pcidev, phys, PAGE_SIZE,
1784                                PCI_DMA_FROMDEVICE);
1785                 qib_release_user_pages(&p, 1);
1786                 cnt++;
1787         }
1788 }
1789 
1790 static int qib_close(struct inode *in, struct file *fp)
1791 {
1792         struct qib_filedata *fd;
1793         struct qib_ctxtdata *rcd;
1794         struct qib_devdata *dd;
1795         unsigned long flags;
1796         unsigned ctxt;
1797 
1798         mutex_lock(&qib_mutex);
1799 
1800         fd = fp->private_data;
1801         fp->private_data = NULL;
1802         rcd = fd->rcd;
1803         if (!rcd) {
1804                 mutex_unlock(&qib_mutex);
1805                 goto bail;
1806         }
1807 
1808         dd = rcd->dd;
1809 
1810         /* ensure all pio buffer writes in progress are flushed */
1811         qib_flush_wc();
1812 
1813         /* drain user sdma queue */
1814         if (fd->pq) {
1815                 qib_user_sdma_queue_drain(rcd->ppd, fd->pq);
1816                 qib_user_sdma_queue_destroy(fd->pq);
1817         }
1818 
1819         if (fd->rec_cpu_num != -1)
1820                 __clear_bit(fd->rec_cpu_num, qib_cpulist);
1821 
1822         if (--rcd->cnt) {
1823                 /*
1824                  * XXX If the master closes the context before the slave(s),
1825                  * revoke the mmap for the eager receive queue so
1826                  * the slave(s) don't wait for receive data forever.
1827                  */
1828                 rcd->active_slaves &= ~(1 << fd->subctxt);
1829                 rcd->subpid[fd->subctxt] = 0;
1830                 mutex_unlock(&qib_mutex);
1831                 goto bail;
1832         }
1833 
1834         /* early; no interrupt users after this */
1835         spin_lock_irqsave(&dd->uctxt_lock, flags);
1836         ctxt = rcd->ctxt;
1837         dd->rcd[ctxt] = NULL;
1838         rcd->pid = 0;
1839         spin_unlock_irqrestore(&dd->uctxt_lock, flags);
1840 
1841         if (rcd->rcvwait_to || rcd->piowait_to ||
1842             rcd->rcvnowait || rcd->pionowait) {
1843                 rcd->rcvwait_to = 0;
1844                 rcd->piowait_to = 0;
1845                 rcd->rcvnowait = 0;
1846                 rcd->pionowait = 0;
1847         }
1848         if (rcd->flag)
1849                 rcd->flag = 0;
1850 
1851         if (dd->kregbase) {
1852                 /* atomically clear receive enable ctxt and intr avail. */
1853                 dd->f_rcvctrl(rcd->ppd, QIB_RCVCTRL_CTXT_DIS |
1854                                   QIB_RCVCTRL_INTRAVAIL_DIS, ctxt);
1855 
1856                 /* clean up the pkeys for this ctxt user */
1857                 qib_clean_part_key(rcd, dd);
1858                 qib_disarm_piobufs(dd, rcd->pio_base, rcd->piocnt);
1859                 qib_chg_pioavailkernel(dd, rcd->pio_base,
1860                                        rcd->piocnt, TXCHK_CHG_TYPE_KERN, NULL);
1861 
1862                 dd->f_clear_tids(dd, rcd);
1863 
1864                 if (dd->pageshadow)
1865                         unlock_expected_tids(rcd);
1866                 qib_stats.sps_ctxts--;
1867                 dd->freectxts++;
1868         }
1869 
1870         mutex_unlock(&qib_mutex);
1871         qib_free_ctxtdata(dd, rcd); /* after releasing the mutex */
1872 
1873 bail:
1874         kfree(fd);
1875         return 0;
1876 }
1877 
1878 static int qib_ctxt_info(struct file *fp, struct qib_ctxt_info __user *uinfo)
1879 {
1880         struct qib_ctxt_info info;
1881         int ret;
1882         size_t sz;
1883         struct qib_ctxtdata *rcd = ctxt_fp(fp);
1884         struct qib_filedata *fd;
1885 
1886         fd = fp->private_data;
1887 
1888         info.num_active = qib_count_active_units();
1889         info.unit = rcd->dd->unit;
1890         info.port = rcd->ppd->port;
1891         info.ctxt = rcd->ctxt;
1892         info.subctxt =  subctxt_fp(fp);
1893         /* Number of user ctxts available for this device. */
1894         info.num_ctxts = rcd->dd->cfgctxts - rcd->dd->first_user_ctxt;
1895         info.num_subctxts = rcd->subctxt_cnt;
1896         info.rec_cpu = fd->rec_cpu_num;
1897         sz = sizeof(info);
1898 
1899         if (copy_to_user(uinfo, &info, sz)) {
1900                 ret = -EFAULT;
1901                 goto bail;
1902         }
1903         ret = 0;
1904 
1905 bail:
1906         return ret;
1907 }
1908 
1909 static int qib_sdma_get_inflight(struct qib_user_sdma_queue *pq,
1910                                  u32 __user *inflightp)
1911 {
1912         const u32 val = qib_user_sdma_inflight_counter(pq);
1913 
1914         if (put_user(val, inflightp))
1915                 return -EFAULT;
1916 
1917         return 0;
1918 }
1919 
1920 static int qib_sdma_get_complete(struct qib_pportdata *ppd,
1921                                  struct qib_user_sdma_queue *pq,
1922                                  u32 __user *completep)
1923 {
1924         u32 val;
1925         int err;
1926 
1927         if (!pq)
1928                 return -EINVAL;
1929 
1930         err = qib_user_sdma_make_progress(ppd, pq);
1931         if (err < 0)
1932                 return err;
1933 
1934         val = qib_user_sdma_complete_counter(pq);
1935         if (put_user(val, completep))
1936                 return -EFAULT;
1937 
1938         return 0;
1939 }
1940 
1941 static int disarm_req_delay(struct qib_ctxtdata *rcd)
1942 {
1943         int ret = 0;
1944 
1945         if (!usable(rcd->ppd)) {
1946                 int i;
1947                 /*
1948                  * if link is down, or otherwise not usable, delay
1949                  * the caller up to 30 seconds, so we don't thrash
1950                  * in trying to get the chip back to ACTIVE, and
1951                  * set flag so they make the call again.
1952                  */
1953                 if (rcd->user_event_mask) {
1954                         /*
1955                          * subctxt_cnt is 0 if not shared, so do base
1956                          * separately, first, then remaining subctxt, if any
1957                          */
1958                         set_bit(_QIB_EVENT_DISARM_BUFS_BIT,
1959                                 &rcd->user_event_mask[0]);
1960                         for (i = 1; i < rcd->subctxt_cnt; i++)
1961                                 set_bit(_QIB_EVENT_DISARM_BUFS_BIT,
1962                                         &rcd->user_event_mask[i]);
1963                 }
1964                 for (i = 0; !usable(rcd->ppd) && i < 300; i++)
1965                         msleep(100);
1966                 ret = -ENETDOWN;
1967         }
1968         return ret;
1969 }
1970 
1971 /*
1972  * Find all user contexts in use, and set the specified bit in their
1973  * event mask.
1974  * See also find_ctxt() for a similar use, that is specific to send buffers.
1975  */
1976 int qib_set_uevent_bits(struct qib_pportdata *ppd, const int evtbit)
1977 {
1978         struct qib_ctxtdata *rcd;
1979         unsigned ctxt;
1980         int ret = 0;
1981         unsigned long flags;
1982 
1983         spin_lock_irqsave(&ppd->dd->uctxt_lock, flags);
1984         for (ctxt = ppd->dd->first_user_ctxt; ctxt < ppd->dd->cfgctxts;
1985              ctxt++) {
1986                 rcd = ppd->dd->rcd[ctxt];
1987                 if (!rcd)
1988                         continue;
1989                 if (rcd->user_event_mask) {
1990                         int i;
1991                         /*
1992                          * subctxt_cnt is 0 if not shared, so do base
1993                          * separately, first, then remaining subctxt, if any
1994                          */
1995                         set_bit(evtbit, &rcd->user_event_mask[0]);
1996                         for (i = 1; i < rcd->subctxt_cnt; i++)
1997                                 set_bit(evtbit, &rcd->user_event_mask[i]);
1998                 }
1999                 ret = 1;
2000                 break;
2001         }
2002         spin_unlock_irqrestore(&ppd->dd->uctxt_lock, flags);
2003 
2004         return ret;
2005 }
2006 
2007 /*
2008  * clear the event notifier events for this context.
2009  * For the DISARM_BUFS case, we also take action (this obsoletes
2010  * the older QIB_CMD_DISARM_BUFS, but we keep it for backwards
2011  * compatibility.
2012  * Other bits don't currently require actions, just atomically clear.
2013  * User process then performs actions appropriate to bit having been
2014  * set, if desired, and checks again in future.
2015  */
2016 static int qib_user_event_ack(struct qib_ctxtdata *rcd, int subctxt,
2017                               unsigned long events)
2018 {
2019         int ret = 0, i;
2020 
2021         for (i = 0; i <= _QIB_MAX_EVENT_BIT; i++) {
2022                 if (!test_bit(i, &events))
2023                         continue;
2024                 if (i == _QIB_EVENT_DISARM_BUFS_BIT) {
2025                         (void)qib_disarm_piobufs_ifneeded(rcd);
2026                         ret = disarm_req_delay(rcd);
2027                 } else
2028                         clear_bit(i, &rcd->user_event_mask[subctxt]);
2029         }
2030         return ret;
2031 }
2032 
2033 static ssize_t qib_write(struct file *fp, const char __user *data,
2034                          size_t count, loff_t *off)
2035 {
2036         const struct qib_cmd __user *ucmd;
2037         struct qib_ctxtdata *rcd;
2038         const void __user *src;
2039         size_t consumed, copy = 0;
2040         struct qib_cmd cmd;
2041         ssize_t ret = 0;
2042         void *dest;
2043 
2044         if (!ib_safe_file_access(fp)) {
2045                 pr_err_once("qib_write: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
2046                             task_tgid_vnr(current), current->comm);
2047                 return -EACCES;
2048         }
2049 
2050         if (count < sizeof(cmd.type)) {
2051                 ret = -EINVAL;
2052                 goto bail;
2053         }
2054 
2055         ucmd = (const struct qib_cmd __user *) data;
2056 
2057         if (copy_from_user(&cmd.type, &ucmd->type, sizeof(cmd.type))) {
2058                 ret = -EFAULT;
2059                 goto bail;
2060         }
2061 
2062         consumed = sizeof(cmd.type);
2063 
2064         switch (cmd.type) {
2065         case QIB_CMD_ASSIGN_CTXT:
2066         case QIB_CMD_USER_INIT:
2067                 copy = sizeof(cmd.cmd.user_info);
2068                 dest = &cmd.cmd.user_info;
2069                 src = &ucmd->cmd.user_info;
2070                 break;
2071 
2072         case QIB_CMD_RECV_CTRL:
2073                 copy = sizeof(cmd.cmd.recv_ctrl);
2074                 dest = &cmd.cmd.recv_ctrl;
2075                 src = &ucmd->cmd.recv_ctrl;
2076                 break;
2077 
2078         case QIB_CMD_CTXT_INFO:
2079                 copy = sizeof(cmd.cmd.ctxt_info);
2080                 dest = &cmd.cmd.ctxt_info;
2081                 src = &ucmd->cmd.ctxt_info;
2082                 break;
2083 
2084         case QIB_CMD_TID_UPDATE:
2085         case QIB_CMD_TID_FREE:
2086                 copy = sizeof(cmd.cmd.tid_info);
2087                 dest = &cmd.cmd.tid_info;
2088                 src = &ucmd->cmd.tid_info;
2089                 break;
2090 
2091         case QIB_CMD_SET_PART_KEY:
2092                 copy = sizeof(cmd.cmd.part_key);
2093                 dest = &cmd.cmd.part_key;
2094                 src = &ucmd->cmd.part_key;
2095                 break;
2096 
2097         case QIB_CMD_DISARM_BUFS:
2098         case QIB_CMD_PIOAVAILUPD: /* force an update of PIOAvail reg */
2099                 copy = 0;
2100                 src = NULL;
2101                 dest = NULL;
2102                 break;
2103 
2104         case QIB_CMD_POLL_TYPE:
2105                 copy = sizeof(cmd.cmd.poll_type);
2106                 dest = &cmd.cmd.poll_type;
2107                 src = &ucmd->cmd.poll_type;
2108                 break;
2109 
2110         case QIB_CMD_ARMLAUNCH_CTRL:
2111                 copy = sizeof(cmd.cmd.armlaunch_ctrl);
2112                 dest = &cmd.cmd.armlaunch_ctrl;
2113                 src = &ucmd->cmd.armlaunch_ctrl;
2114                 break;
2115 
2116         case QIB_CMD_SDMA_INFLIGHT:
2117                 copy = sizeof(cmd.cmd.sdma_inflight);
2118                 dest = &cmd.cmd.sdma_inflight;
2119                 src = &ucmd->cmd.sdma_inflight;
2120                 break;
2121 
2122         case QIB_CMD_SDMA_COMPLETE:
2123                 copy = sizeof(cmd.cmd.sdma_complete);
2124                 dest = &cmd.cmd.sdma_complete;
2125                 src = &ucmd->cmd.sdma_complete;
2126                 break;
2127 
2128         case QIB_CMD_ACK_EVENT:
2129                 copy = sizeof(cmd.cmd.event_mask);
2130                 dest = &cmd.cmd.event_mask;
2131                 src = &ucmd->cmd.event_mask;
2132                 break;
2133 
2134         default:
2135                 ret = -EINVAL;
2136                 goto bail;
2137         }
2138 
2139         if (copy) {
2140                 if ((count - consumed) < copy) {
2141                         ret = -EINVAL;
2142                         goto bail;
2143                 }
2144                 if (copy_from_user(dest, src, copy)) {
2145                         ret = -EFAULT;
2146                         goto bail;
2147                 }
2148                 consumed += copy;
2149         }
2150 
2151         rcd = ctxt_fp(fp);
2152         if (!rcd && cmd.type != QIB_CMD_ASSIGN_CTXT) {
2153                 ret = -EINVAL;
2154                 goto bail;
2155         }
2156 
2157         switch (cmd.type) {
2158         case QIB_CMD_ASSIGN_CTXT:
2159                 if (rcd) {
2160                         ret = -EINVAL;
2161                         goto bail;
2162                 }
2163 
2164                 ret = qib_assign_ctxt(fp, &cmd.cmd.user_info);
2165                 if (ret)
2166                         goto bail;
2167                 break;
2168 
2169         case QIB_CMD_USER_INIT:
2170                 ret = qib_do_user_init(fp, &cmd.cmd.user_info);
2171                 if (ret)
2172                         goto bail;
2173                 ret = qib_get_base_info(fp, u64_to_user_ptr(
2174                                           cmd.cmd.user_info.spu_base_info),
2175                                         cmd.cmd.user_info.spu_base_info_size);
2176                 break;
2177 
2178         case QIB_CMD_RECV_CTRL:
2179                 ret = qib_manage_rcvq(rcd, subctxt_fp(fp), cmd.cmd.recv_ctrl);
2180                 break;
2181 
2182         case QIB_CMD_CTXT_INFO:
2183                 ret = qib_ctxt_info(fp, (struct qib_ctxt_info __user *)
2184                                     (unsigned long) cmd.cmd.ctxt_info);
2185                 break;
2186 
2187         case QIB_CMD_TID_UPDATE:
2188                 ret = qib_tid_update(rcd, fp, &cmd.cmd.tid_info);
2189                 break;
2190 
2191         case QIB_CMD_TID_FREE:
2192                 ret = qib_tid_free(rcd, subctxt_fp(fp), &cmd.cmd.tid_info);
2193                 break;
2194 
2195         case QIB_CMD_SET_PART_KEY:
2196                 ret = qib_set_part_key(rcd, cmd.cmd.part_key);
2197                 break;
2198 
2199         case QIB_CMD_DISARM_BUFS:
2200                 (void)qib_disarm_piobufs_ifneeded(rcd);
2201                 ret = disarm_req_delay(rcd);
2202                 break;
2203 
2204         case QIB_CMD_PIOAVAILUPD:
2205                 qib_force_pio_avail_update(rcd->dd);
2206                 break;
2207 
2208         case QIB_CMD_POLL_TYPE:
2209                 rcd->poll_type = cmd.cmd.poll_type;
2210                 break;
2211 
2212         case QIB_CMD_ARMLAUNCH_CTRL:
2213                 rcd->dd->f_set_armlaunch(rcd->dd, cmd.cmd.armlaunch_ctrl);
2214                 break;
2215 
2216         case QIB_CMD_SDMA_INFLIGHT:
2217                 ret = qib_sdma_get_inflight(user_sdma_queue_fp(fp),
2218                                             (u32 __user *) (unsigned long)
2219                                             cmd.cmd.sdma_inflight);
2220                 break;
2221 
2222         case QIB_CMD_SDMA_COMPLETE:
2223                 ret = qib_sdma_get_complete(rcd->ppd,
2224                                             user_sdma_queue_fp(fp),
2225                                             (u32 __user *) (unsigned long)
2226                                             cmd.cmd.sdma_complete);
2227                 break;
2228 
2229         case QIB_CMD_ACK_EVENT:
2230                 ret = qib_user_event_ack(rcd, subctxt_fp(fp),
2231                                          cmd.cmd.event_mask);
2232                 break;
2233         }
2234 
2235         if (ret >= 0)
2236                 ret = consumed;
2237 
2238 bail:
2239         return ret;
2240 }
2241 
2242 static ssize_t qib_write_iter(struct kiocb *iocb, struct iov_iter *from)
2243 {
2244         struct qib_filedata *fp = iocb->ki_filp->private_data;
2245         struct qib_ctxtdata *rcd = ctxt_fp(iocb->ki_filp);
2246         struct qib_user_sdma_queue *pq = fp->pq;
2247 
2248         if (!iter_is_iovec(from) || !from->nr_segs || !pq)
2249                 return -EINVAL;
2250                          
2251         return qib_user_sdma_writev(rcd, pq, from->iov, from->nr_segs);
2252 }
2253 
2254 static struct class *qib_class;
2255 static dev_t qib_dev;
2256 
2257 int qib_cdev_init(int minor, const char *name,
2258                   const struct file_operations *fops,
2259                   struct cdev **cdevp, struct device **devp)
2260 {
2261         const dev_t dev = MKDEV(MAJOR(qib_dev), minor);
2262         struct cdev *cdev;
2263         struct device *device = NULL;
2264         int ret;
2265 
2266         cdev = cdev_alloc();
2267         if (!cdev) {
2268                 pr_err("Could not allocate cdev for minor %d, %s\n",
2269                        minor, name);
2270                 ret = -ENOMEM;
2271                 goto done;
2272         }
2273 
2274         cdev->owner = THIS_MODULE;
2275         cdev->ops = fops;
2276         kobject_set_name(&cdev->kobj, name);
2277 
2278         ret = cdev_add(cdev, dev, 1);
2279         if (ret < 0) {
2280                 pr_err("Could not add cdev for minor %d, %s (err %d)\n",
2281                        minor, name, -ret);
2282                 goto err_cdev;
2283         }
2284 
2285         device = device_create(qib_class, NULL, dev, NULL, "%s", name);
2286         if (!IS_ERR(device))
2287                 goto done;
2288         ret = PTR_ERR(device);
2289         device = NULL;
2290         pr_err("Could not create device for minor %d, %s (err %d)\n",
2291                minor, name, -ret);
2292 err_cdev:
2293         cdev_del(cdev);
2294         cdev = NULL;
2295 done:
2296         *cdevp = cdev;
2297         *devp = device;
2298         return ret;
2299 }
2300 
2301 void qib_cdev_cleanup(struct cdev **cdevp, struct device **devp)
2302 {
2303         struct device *device = *devp;
2304 
2305         if (device) {
2306                 device_unregister(device);
2307                 *devp = NULL;
2308         }
2309 
2310         if (*cdevp) {
2311                 cdev_del(*cdevp);
2312                 *cdevp = NULL;
2313         }
2314 }
2315 
2316 static struct cdev *wildcard_cdev;
2317 static struct device *wildcard_device;
2318 
2319 int __init qib_dev_init(void)
2320 {
2321         int ret;
2322 
2323         ret = alloc_chrdev_region(&qib_dev, 0, QIB_NMINORS, QIB_DRV_NAME);
2324         if (ret < 0) {
2325                 pr_err("Could not allocate chrdev region (err %d)\n", -ret);
2326                 goto done;
2327         }
2328 
2329         qib_class = class_create(THIS_MODULE, "ipath");
2330         if (IS_ERR(qib_class)) {
2331                 ret = PTR_ERR(qib_class);
2332                 pr_err("Could not create device class (err %d)\n", -ret);
2333                 unregister_chrdev_region(qib_dev, QIB_NMINORS);
2334         }
2335 
2336 done:
2337         return ret;
2338 }
2339 
2340 void qib_dev_cleanup(void)
2341 {
2342         if (qib_class) {
2343                 class_destroy(qib_class);
2344                 qib_class = NULL;
2345         }
2346 
2347         unregister_chrdev_region(qib_dev, QIB_NMINORS);
2348 }
2349 
2350 static atomic_t user_count = ATOMIC_INIT(0);
2351 
2352 static void qib_user_remove(struct qib_devdata *dd)
2353 {
2354         if (atomic_dec_return(&user_count) == 0)
2355                 qib_cdev_cleanup(&wildcard_cdev, &wildcard_device);
2356 
2357         qib_cdev_cleanup(&dd->user_cdev, &dd->user_device);
2358 }
2359 
2360 static int qib_user_add(struct qib_devdata *dd)
2361 {
2362         char name[10];
2363         int ret;
2364 
2365         if (atomic_inc_return(&user_count) == 1) {
2366                 ret = qib_cdev_init(0, "ipath", &qib_file_ops,
2367                                     &wildcard_cdev, &wildcard_device);
2368                 if (ret)
2369                         goto done;
2370         }
2371 
2372         snprintf(name, sizeof(name), "ipath%d", dd->unit);
2373         ret = qib_cdev_init(dd->unit + 1, name, &qib_file_ops,
2374                             &dd->user_cdev, &dd->user_device);
2375         if (ret)
2376                 qib_user_remove(dd);
2377 done:
2378         return ret;
2379 }
2380 
2381 /*
2382  * Create per-unit files in /dev
2383  */
2384 int qib_device_create(struct qib_devdata *dd)
2385 {
2386         int r, ret;
2387 
2388         r = qib_user_add(dd);
2389         ret = qib_diag_add(dd);
2390         if (r && !ret)
2391                 ret = r;
2392         return ret;
2393 }
2394 
2395 /*
2396  * Remove per-unit files in /dev
2397  * void, core kernel returns no errors for this stuff
2398  */
2399 void qib_device_remove(struct qib_devdata *dd)
2400 {
2401         qib_user_remove(dd);
2402         qib_diag_remove(dd);
2403 }