[PATCH] IB/ipath: fix a bug that results in addresses near 0 being written via DMA
[linux-2.6.git] / drivers / infiniband / hw / ipath / ipath_file_ops.c
1 /*
2  * Copyright (c) 2006 QLogic, Inc. All rights reserved.
3  * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *        copyright notice, this list of conditions and the following
17  *        disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer in the documentation and/or other materials
22  *        provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33
34 #include <linux/pci.h>
35 #include <linux/poll.h>
36 #include <linux/cdev.h>
37 #include <linux/swap.h>
38 #include <linux/vmalloc.h>
39 #include <asm/pgtable.h>
40
41 #include "ipath_kernel.h"
42 #include "ips_common.h"
43 #include "ipath_layer.h"
44
45 static int ipath_open(struct inode *, struct file *);
46 static int ipath_close(struct inode *, struct file *);
47 static ssize_t ipath_write(struct file *, const char __user *, size_t,
48                            loff_t *);
49 static unsigned int ipath_poll(struct file *, struct poll_table_struct *);
50 static int ipath_mmap(struct file *, struct vm_area_struct *);
51
52 static struct file_operations ipath_file_ops = {
53         .owner = THIS_MODULE,
54         .write = ipath_write,
55         .open = ipath_open,
56         .release = ipath_close,
57         .poll = ipath_poll,
58         .mmap = ipath_mmap
59 };
60
61 static int ipath_get_base_info(struct ipath_portdata *pd,
62                                void __user *ubase, size_t ubase_size)
63 {
64         int ret = 0;
65         struct ipath_base_info *kinfo = NULL;
66         struct ipath_devdata *dd = pd->port_dd;
67
68         if (ubase_size < sizeof(*kinfo)) {
69                 ipath_cdbg(PROC,
70                            "Base size %lu, need %lu (version mismatch?)\n",
71                            (unsigned long) ubase_size,
72                            (unsigned long) sizeof(*kinfo));
73                 ret = -EINVAL;
74                 goto bail;
75         }
76
77         kinfo = kzalloc(sizeof(*kinfo), GFP_KERNEL);
78         if (kinfo == NULL) {
79                 ret = -ENOMEM;
80                 goto bail;
81         }
82
83         ret = dd->ipath_f_get_base_info(pd, kinfo);
84         if (ret < 0)
85                 goto bail;
86
87         kinfo->spi_rcvhdr_cnt = dd->ipath_rcvhdrcnt;
88         kinfo->spi_rcvhdrent_size = dd->ipath_rcvhdrentsize;
89         kinfo->spi_tidegrcnt = dd->ipath_rcvegrcnt;
90         kinfo->spi_rcv_egrbufsize = dd->ipath_rcvegrbufsize;
91         /*
92          * have to mmap whole thing
93          */
94         kinfo->spi_rcv_egrbuftotlen =
95                 pd->port_rcvegrbuf_chunks * pd->port_rcvegrbuf_size;
96         kinfo->spi_rcv_egrperchunk = pd->port_rcvegrbufs_perchunk;
97         kinfo->spi_rcv_egrchunksize = kinfo->spi_rcv_egrbuftotlen /
98                 pd->port_rcvegrbuf_chunks;
99         kinfo->spi_tidcnt = dd->ipath_rcvtidcnt;
100         /*
101          * for this use, may be ipath_cfgports summed over all chips that
102          * are are configured and present
103          */
104         kinfo->spi_nports = dd->ipath_cfgports;
105         /* unit (chip/board) our port is on */
106         kinfo->spi_unit = dd->ipath_unit;
107         /* for now, only a single page */
108         kinfo->spi_tid_maxsize = PAGE_SIZE;
109
110         /*
111          * Doing this per port, and based on the skip value, etc.  This has
112          * to be the actual buffer size, since the protocol code treats it
113          * as an array.
114          *
115          * These have to be set to user addresses in the user code via mmap.
116          * These values are used on return to user code for the mmap target
117          * addresses only.  For 32 bit, same 44 bit address problem, so use
118          * the physical address, not virtual.  Before 2.6.11, using the
119          * page_address() macro worked, but in 2.6.11, even that returns the
120          * full 64 bit address (upper bits all 1's).  So far, using the
121          * physical addresses (or chip offsets, for chip mapping) works, but
122          * no doubt some future kernel release will chang that, and we'll be
123          * on to yet another method of dealing with this
124          */
125         kinfo->spi_rcvhdr_base = (u64) pd->port_rcvhdrq_phys;
126         kinfo->spi_rcvhdr_tailaddr = (u64)pd->port_rcvhdrqtailaddr_phys;
127         kinfo->spi_rcv_egrbufs = (u64) pd->port_rcvegr_phys;
128         kinfo->spi_pioavailaddr = (u64) dd->ipath_pioavailregs_phys;
129         kinfo->spi_status = (u64) kinfo->spi_pioavailaddr +
130                 (void *) dd->ipath_statusp -
131                 (void *) dd->ipath_pioavailregs_dma;
132         kinfo->spi_piobufbase = (u64) pd->port_piobufs;
133         kinfo->__spi_uregbase =
134                 dd->ipath_uregbase + dd->ipath_palign * pd->port_port;
135
136         kinfo->spi_pioindex = dd->ipath_pbufsport * (pd->port_port - 1);
137         kinfo->spi_piocnt = dd->ipath_pbufsport;
138         kinfo->spi_pioalign = dd->ipath_palign;
139
140         kinfo->spi_qpair = IPATH_KD_QP;
141         kinfo->spi_piosize = dd->ipath_ibmaxlen;
142         kinfo->spi_mtu = dd->ipath_ibmaxlen;    /* maxlen, not ibmtu */
143         kinfo->spi_port = pd->port_port;
144         kinfo->spi_sw_version = IPATH_KERN_SWVERSION;
145         kinfo->spi_hw_version = dd->ipath_revision;
146
147         if (copy_to_user(ubase, kinfo, sizeof(*kinfo)))
148                 ret = -EFAULT;
149
150 bail:
151         kfree(kinfo);
152         return ret;
153 }
154
155 /**
156  * ipath_tid_update - update a port TID
157  * @pd: the port
158  * @ti: the TID information
159  *
160  * The new implementation as of Oct 2004 is that the driver assigns
161  * the tid and returns it to the caller.   To make it easier to
162  * catch bugs, and to reduce search time, we keep a cursor for
163  * each port, walking the shadow tid array to find one that's not
164  * in use.
165  *
166  * For now, if we can't allocate the full list, we fail, although
167  * in the long run, we'll allocate as many as we can, and the
168  * caller will deal with that by trying the remaining pages later.
169  * That means that when we fail, we have to mark the tids as not in
170  * use again, in our shadow copy.
171  *
172  * It's up to the caller to free the tids when they are done.
173  * We'll unlock the pages as they free them.
174  *
175  * Also, right now we are locking one page at a time, but since
176  * the intended use of this routine is for a single group of
177  * virtually contiguous pages, that should change to improve
178  * performance.
179  */
180 static int ipath_tid_update(struct ipath_portdata *pd,
181                             const struct ipath_tid_info *ti)
182 {
183         int ret = 0, ntids;
184         u32 tid, porttid, cnt, i, tidcnt;
185         u16 *tidlist;
186         struct ipath_devdata *dd = pd->port_dd;
187         u64 physaddr;
188         unsigned long vaddr;
189         u64 __iomem *tidbase;
190         unsigned long tidmap[8];
191         struct page **pagep = NULL;
192
193         if (!dd->ipath_pageshadow) {
194                 ret = -ENOMEM;
195                 goto done;
196         }
197
198         cnt = ti->tidcnt;
199         if (!cnt) {
200                 ipath_dbg("After copyin, tidcnt 0, tidlist %llx\n",
201                           (unsigned long long) ti->tidlist);
202                 /*
203                  * Should we treat as success?  likely a bug
204                  */
205                 ret = -EFAULT;
206                 goto done;
207         }
208         tidcnt = dd->ipath_rcvtidcnt;
209         if (cnt >= tidcnt) {
210                 /* make sure it all fits in port_tid_pg_list */
211                 dev_info(&dd->pcidev->dev, "Process tried to allocate %u "
212                          "TIDs, only trying max (%u)\n", cnt, tidcnt);
213                 cnt = tidcnt;
214         }
215         pagep = (struct page **)pd->port_tid_pg_list;
216         tidlist = (u16 *) (&pagep[cnt]);
217
218         memset(tidmap, 0, sizeof(tidmap));
219         tid = pd->port_tidcursor;
220         /* before decrement; chip actual # */
221         porttid = pd->port_port * tidcnt;
222         ntids = tidcnt;
223         tidbase = (u64 __iomem *) (((char __iomem *) dd->ipath_kregbase) +
224                                    dd->ipath_rcvtidbase +
225                                    porttid * sizeof(*tidbase));
226
227         ipath_cdbg(VERBOSE, "Port%u %u tids, cursor %u, tidbase %p\n",
228                    pd->port_port, cnt, tid, tidbase);
229
230         /* virtual address of first page in transfer */
231         vaddr = ti->tidvaddr;
232         if (!access_ok(VERIFY_WRITE, (void __user *) vaddr,
233                        cnt * PAGE_SIZE)) {
234                 ipath_dbg("Fail vaddr %p, %u pages, !access_ok\n",
235                           (void *)vaddr, cnt);
236                 ret = -EFAULT;
237                 goto done;
238         }
239         ret = ipath_get_user_pages(vaddr, cnt, pagep);
240         if (ret) {
241                 if (ret == -EBUSY) {
242                         ipath_dbg("Failed to lock addr %p, %u pages "
243                                   "(already locked)\n",
244                                   (void *) vaddr, cnt);
245                         /*
246                          * for now, continue, and see what happens but with
247                          * the new implementation, this should never happen,
248                          * unless perhaps the user has mpin'ed the pages
249                          * themselves (something we need to test)
250                          */
251                         ret = 0;
252                 } else {
253                         dev_info(&dd->pcidev->dev,
254                                  "Failed to lock addr %p, %u pages: "
255                                  "errno %d\n", (void *) vaddr, cnt, -ret);
256                         goto done;
257                 }
258         }
259         for (i = 0; i < cnt; i++, vaddr += PAGE_SIZE) {
260                 for (; ntids--; tid++) {
261                         if (tid == tidcnt)
262                                 tid = 0;
263                         if (!dd->ipath_pageshadow[porttid + tid])
264                                 break;
265                 }
266                 if (ntids < 0) {
267                         /*
268                          * oops, wrapped all the way through their TIDs,
269                          * and didn't have enough free; see comments at
270                          * start of routine
271                          */
272                         ipath_dbg("Not enough free TIDs for %u pages "
273                                   "(index %d), failing\n", cnt, i);
274                         i--;    /* last tidlist[i] not filled in */
275                         ret = -ENOMEM;
276                         break;
277                 }
278                 tidlist[i] = tid;
279                 ipath_cdbg(VERBOSE, "Updating idx %u to TID %u, "
280                            "vaddr %lx\n", i, tid, vaddr);
281                 /* we "know" system pages and TID pages are same size */
282                 dd->ipath_pageshadow[porttid + tid] = pagep[i];
283                 /*
284                  * don't need atomic or it's overhead
285                  */
286                 __set_bit(tid, tidmap);
287                 physaddr = page_to_phys(pagep[i]);
288                 ipath_stats.sps_pagelocks++;
289                 ipath_cdbg(VERBOSE,
290                            "TID %u, vaddr %lx, physaddr %llx pgp %p\n",
291                            tid, vaddr, (unsigned long long) physaddr,
292                            pagep[i]);
293                 dd->ipath_f_put_tid(dd, &tidbase[tid], 1, physaddr);
294                 /*
295                  * don't check this tid in ipath_portshadow, since we
296                  * just filled it in; start with the next one.
297                  */
298                 tid++;
299         }
300
301         if (ret) {
302                 u32 limit;
303         cleanup:
304                 /* jump here if copy out of updated info failed... */
305                 ipath_dbg("After failure (ret=%d), undo %d of %d entries\n",
306                           -ret, i, cnt);
307                 /* same code that's in ipath_free_tid() */
308                 limit = sizeof(tidmap) * BITS_PER_BYTE;
309                 if (limit > tidcnt)
310                         /* just in case size changes in future */
311                         limit = tidcnt;
312                 tid = find_first_bit((const unsigned long *)tidmap, limit);
313                 for (; tid < limit; tid++) {
314                         if (!test_bit(tid, tidmap))
315                                 continue;
316                         if (dd->ipath_pageshadow[porttid + tid]) {
317                                 ipath_cdbg(VERBOSE, "Freeing TID %u\n",
318                                            tid);
319                                 dd->ipath_f_put_tid(dd, &tidbase[tid], 1,
320                                                     dd->ipath_tidinvalid);
321                                 dd->ipath_pageshadow[porttid + tid] = NULL;
322                                 ipath_stats.sps_pageunlocks++;
323                         }
324                 }
325                 ipath_release_user_pages(pagep, cnt);
326         } else {
327                 /*
328                  * Copy the updated array, with ipath_tid's filled in, back
329                  * to user.  Since we did the copy in already, this "should
330                  * never fail" If it does, we have to clean up...
331                  */
332                 if (copy_to_user((void __user *)
333                                  (unsigned long) ti->tidlist,
334                                  tidlist, cnt * sizeof(*tidlist))) {
335                         ret = -EFAULT;
336                         goto cleanup;
337                 }
338                 if (copy_to_user((void __user *) (unsigned long) ti->tidmap,
339                                  tidmap, sizeof tidmap)) {
340                         ret = -EFAULT;
341                         goto cleanup;
342                 }
343                 if (tid == tidcnt)
344                         tid = 0;
345                 pd->port_tidcursor = tid;
346         }
347
348 done:
349         if (ret)
350                 ipath_dbg("Failed to map %u TID pages, failing with %d\n",
351                           ti->tidcnt, -ret);
352         return ret;
353 }
354
355 /**
356  * ipath_tid_free - free a port TID
357  * @pd: the port
358  * @ti: the TID info
359  *
360  * right now we are unlocking one page at a time, but since
361  * the intended use of this routine is for a single group of
362  * virtually contiguous pages, that should change to improve
363  * performance.  We check that the TID is in range for this port
364  * but otherwise don't check validity; if user has an error and
365  * frees the wrong tid, it's only their own data that can thereby
366  * be corrupted.  We do check that the TID was in use, for sanity
367  * We always use our idea of the saved address, not the address that
368  * they pass in to us.
369  */
370
371 static int ipath_tid_free(struct ipath_portdata *pd,
372                           const struct ipath_tid_info *ti)
373 {
374         int ret = 0;
375         u32 tid, porttid, cnt, limit, tidcnt;
376         struct ipath_devdata *dd = pd->port_dd;
377         u64 __iomem *tidbase;
378         unsigned long tidmap[8];
379
380         if (!dd->ipath_pageshadow) {
381                 ret = -ENOMEM;
382                 goto done;
383         }
384
385         if (copy_from_user(tidmap, (void __user *)(unsigned long)ti->tidmap,
386                            sizeof tidmap)) {
387                 ret = -EFAULT;
388                 goto done;
389         }
390
391         porttid = pd->port_port * dd->ipath_rcvtidcnt;
392         tidbase = (u64 __iomem *) ((char __iomem *)(dd->ipath_kregbase) +
393                                    dd->ipath_rcvtidbase +
394                                    porttid * sizeof(*tidbase));
395
396         tidcnt = dd->ipath_rcvtidcnt;
397         limit = sizeof(tidmap) * BITS_PER_BYTE;
398         if (limit > tidcnt)
399                 /* just in case size changes in future */
400                 limit = tidcnt;
401         tid = find_first_bit(tidmap, limit);
402         ipath_cdbg(VERBOSE, "Port%u free %u tids; first bit (max=%d) "
403                    "set is %d, porttid %u\n", pd->port_port, ti->tidcnt,
404                    limit, tid, porttid);
405         for (cnt = 0; tid < limit; tid++) {
406                 /*
407                  * small optimization; if we detect a run of 3 or so without
408                  * any set, use find_first_bit again.  That's mainly to
409                  * accelerate the case where we wrapped, so we have some at
410                  * the beginning, and some at the end, and a big gap
411                  * in the middle.
412                  */
413                 if (!test_bit(tid, tidmap))
414                         continue;
415                 cnt++;
416                 if (dd->ipath_pageshadow[porttid + tid]) {
417                         ipath_cdbg(VERBOSE, "PID %u freeing TID %u\n",
418                                    pd->port_pid, tid);
419                         dd->ipath_f_put_tid(dd, &tidbase[tid], 1,
420                                             dd->ipath_tidinvalid);
421                         ipath_release_user_pages(
422                                 &dd->ipath_pageshadow[porttid + tid], 1);
423                         dd->ipath_pageshadow[porttid + tid] = NULL;
424                         ipath_stats.sps_pageunlocks++;
425                 } else
426                         ipath_dbg("Unused tid %u, ignoring\n", tid);
427         }
428         if (cnt != ti->tidcnt)
429                 ipath_dbg("passed in tidcnt %d, only %d bits set in map\n",
430                           ti->tidcnt, cnt);
431 done:
432         if (ret)
433                 ipath_dbg("Failed to unmap %u TID pages, failing with %d\n",
434                           ti->tidcnt, -ret);
435         return ret;
436 }
437
438 /**
439  * ipath_set_part_key - set a partition key
440  * @pd: the port
441  * @key: the key
442  *
443  * We can have up to 4 active at a time (other than the default, which is
444  * always allowed).  This is somewhat tricky, since multiple ports may set
445  * the same key, so we reference count them, and clean up at exit.  All 4
446  * partition keys are packed into a single infinipath register.  It's an
447  * error for a process to set the same pkey multiple times.  We provide no
448  * mechanism to de-allocate a pkey at this time, we may eventually need to
449  * do that.  I've used the atomic operations, and no locking, and only make
450  * a single pass through what's available.  This should be more than
451  * adequate for some time. I'll think about spinlocks or the like if and as
452  * it's necessary.
453  */
454 static int ipath_set_part_key(struct ipath_portdata *pd, u16 key)
455 {
456         struct ipath_devdata *dd = pd->port_dd;
457         int i, any = 0, pidx = -1;
458         u16 lkey = key & 0x7FFF;
459         int ret;
460
461         if (lkey == (IPS_DEFAULT_P_KEY & 0x7FFF)) {
462                 /* nothing to do; this key always valid */
463                 ret = 0;
464                 goto bail;
465         }
466
467         ipath_cdbg(VERBOSE, "p%u try to set pkey %hx, current keys "
468                    "%hx:%x %hx:%x %hx:%x %hx:%x\n",
469                    pd->port_port, key, dd->ipath_pkeys[0],
470                    atomic_read(&dd->ipath_pkeyrefs[0]), dd->ipath_pkeys[1],
471                    atomic_read(&dd->ipath_pkeyrefs[1]), dd->ipath_pkeys[2],
472                    atomic_read(&dd->ipath_pkeyrefs[2]), dd->ipath_pkeys[3],
473                    atomic_read(&dd->ipath_pkeyrefs[3]));
474
475         if (!lkey) {
476                 ipath_cdbg(PROC, "p%u tries to set key 0, not allowed\n",
477                            pd->port_port);
478                 ret = -EINVAL;
479                 goto bail;
480         }
481
482         /*
483          * Set the full membership bit, because it has to be
484          * set in the register or the packet, and it seems
485          * cleaner to set in the register than to force all
486          * callers to set it. (see bug 4331)
487          */
488         key |= 0x8000;
489
490         for (i = 0; i < ARRAY_SIZE(pd->port_pkeys); i++) {
491                 if (!pd->port_pkeys[i] && pidx == -1)
492                         pidx = i;
493                 if (pd->port_pkeys[i] == key) {
494                         ipath_cdbg(VERBOSE, "p%u tries to set same pkey "
495                                    "(%x) more than once\n",
496                                    pd->port_port, key);
497                         ret = -EEXIST;
498                         goto bail;
499                 }
500         }
501         if (pidx == -1) {
502                 ipath_dbg("All pkeys for port %u already in use, "
503                           "can't set %x\n", pd->port_port, key);
504                 ret = -EBUSY;
505                 goto bail;
506         }
507         for (any = i = 0; i < ARRAY_SIZE(dd->ipath_pkeys); i++) {
508                 if (!dd->ipath_pkeys[i]) {
509                         any++;
510                         continue;
511                 }
512                 if (dd->ipath_pkeys[i] == key) {
513                         atomic_t *pkrefs = &dd->ipath_pkeyrefs[i];
514
515                         if (atomic_inc_return(pkrefs) > 1) {
516                                 pd->port_pkeys[pidx] = key;
517                                 ipath_cdbg(VERBOSE, "p%u set key %x "
518                                            "matches #%d, count now %d\n",
519                                            pd->port_port, key, i,
520                                            atomic_read(pkrefs));
521                                 ret = 0;
522                                 goto bail;
523                         } else {
524                                 /*
525                                  * lost race, decrement count, catch below
526                                  */
527                                 atomic_dec(pkrefs);
528                                 ipath_cdbg(VERBOSE, "Lost race, count was "
529                                            "0, after dec, it's %d\n",
530                                            atomic_read(pkrefs));
531                                 any++;
532                         }
533                 }
534                 if ((dd->ipath_pkeys[i] & 0x7FFF) == lkey) {
535                         /*
536                          * It makes no sense to have both the limited and
537                          * full membership PKEY set at the same time since
538                          * the unlimited one will disable the limited one.
539                          */
540                         ret = -EEXIST;
541                         goto bail;
542                 }
543         }
544         if (!any) {
545                 ipath_dbg("port %u, all pkeys already in use, "
546                           "can't set %x\n", pd->port_port, key);
547                 ret = -EBUSY;
548                 goto bail;
549         }
550         for (any = i = 0; i < ARRAY_SIZE(dd->ipath_pkeys); i++) {
551                 if (!dd->ipath_pkeys[i] &&
552                     atomic_inc_return(&dd->ipath_pkeyrefs[i]) == 1) {
553                         u64 pkey;
554
555                         /* for ipathstats, etc. */
556                         ipath_stats.sps_pkeys[i] = lkey;
557                         pd->port_pkeys[pidx] = dd->ipath_pkeys[i] = key;
558                         pkey =
559                                 (u64) dd->ipath_pkeys[0] |
560                                 ((u64) dd->ipath_pkeys[1] << 16) |
561                                 ((u64) dd->ipath_pkeys[2] << 32) |
562                                 ((u64) dd->ipath_pkeys[3] << 48);
563                         ipath_cdbg(PROC, "p%u set key %x in #%d, "
564                                    "portidx %d, new pkey reg %llx\n",
565                                    pd->port_port, key, i, pidx,
566                                    (unsigned long long) pkey);
567                         ipath_write_kreg(
568                                 dd, dd->ipath_kregs->kr_partitionkey, pkey);
569
570                         ret = 0;
571                         goto bail;
572                 }
573         }
574         ipath_dbg("port %u, all pkeys already in use 2nd pass, "
575                   "can't set %x\n", pd->port_port, key);
576         ret = -EBUSY;
577
578 bail:
579         return ret;
580 }
581
582 /**
583  * ipath_manage_rcvq - manage a port's receive queue
584  * @pd: the port
585  * @start_stop: action to carry out
586  *
587  * start_stop == 0 disables receive on the port, for use in queue
588  * overflow conditions.  start_stop==1 re-enables, to be used to
589  * re-init the software copy of the head register
590  */
591 static int ipath_manage_rcvq(struct ipath_portdata *pd, int start_stop)
592 {
593         struct ipath_devdata *dd = pd->port_dd;
594         u64 tval;
595
596         ipath_cdbg(PROC, "%sabling rcv for unit %u port %u\n",
597                    start_stop ? "en" : "dis", dd->ipath_unit,
598                    pd->port_port);
599         /* atomically clear receive enable port. */
600         if (start_stop) {
601                 /*
602                  * On enable, force in-memory copy of the tail register to
603                  * 0, so that protocol code doesn't have to worry about
604                  * whether or not the chip has yet updated the in-memory
605                  * copy or not on return from the system call. The chip
606                  * always resets it's tail register back to 0 on a
607                  * transition from disabled to enabled.  This could cause a
608                  * problem if software was broken, and did the enable w/o
609                  * the disable, but eventually the in-memory copy will be
610                  * updated and correct itself, even in the face of software
611                  * bugs.
612                  */
613                 *pd->port_rcvhdrtail_kvaddr = 0;
614                 set_bit(INFINIPATH_R_PORTENABLE_SHIFT + pd->port_port,
615                         &dd->ipath_rcvctrl);
616         } else
617                 clear_bit(INFINIPATH_R_PORTENABLE_SHIFT + pd->port_port,
618                           &dd->ipath_rcvctrl);
619         ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
620                          dd->ipath_rcvctrl);
621         /* now be sure chip saw it before we return */
622         tval = ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
623         if (start_stop) {
624                 /*
625                  * And try to be sure that tail reg update has happened too.
626                  * This should in theory interlock with the RXE changes to
627                  * the tail register.  Don't assign it to the tail register
628                  * in memory copy, since we could overwrite an update by the
629                  * chip if we did.
630                  */
631                 tval = ipath_read_ureg32(dd, ur_rcvhdrtail, pd->port_port);
632         }
633         /* always; new head should be equal to new tail; see above */
634         return 0;
635 }
636
637 static void ipath_clean_part_key(struct ipath_portdata *pd,
638                                  struct ipath_devdata *dd)
639 {
640         int i, j, pchanged = 0;
641         u64 oldpkey;
642
643         /* for debugging only */
644         oldpkey = (u64) dd->ipath_pkeys[0] |
645                 ((u64) dd->ipath_pkeys[1] << 16) |
646                 ((u64) dd->ipath_pkeys[2] << 32) |
647                 ((u64) dd->ipath_pkeys[3] << 48);
648
649         for (i = 0; i < ARRAY_SIZE(pd->port_pkeys); i++) {
650                 if (!pd->port_pkeys[i])
651                         continue;
652                 ipath_cdbg(VERBOSE, "look for key[%d] %hx in pkeys\n", i,
653                            pd->port_pkeys[i]);
654                 for (j = 0; j < ARRAY_SIZE(dd->ipath_pkeys); j++) {
655                         /* check for match independent of the global bit */
656                         if ((dd->ipath_pkeys[j] & 0x7fff) !=
657                             (pd->port_pkeys[i] & 0x7fff))
658                                 continue;
659                         if (atomic_dec_and_test(&dd->ipath_pkeyrefs[j])) {
660                                 ipath_cdbg(VERBOSE, "p%u clear key "
661                                            "%x matches #%d\n",
662                                            pd->port_port,
663                                            pd->port_pkeys[i], j);
664                                 ipath_stats.sps_pkeys[j] =
665                                         dd->ipath_pkeys[j] = 0;
666                                 pchanged++;
667                         }
668                         else ipath_cdbg(
669                                 VERBOSE, "p%u key %x matches #%d, "
670                                 "but ref still %d\n", pd->port_port,
671                                 pd->port_pkeys[i], j,
672                                 atomic_read(&dd->ipath_pkeyrefs[j]));
673                         break;
674                 }
675                 pd->port_pkeys[i] = 0;
676         }
677         if (pchanged) {
678                 u64 pkey = (u64) dd->ipath_pkeys[0] |
679                         ((u64) dd->ipath_pkeys[1] << 16) |
680                         ((u64) dd->ipath_pkeys[2] << 32) |
681                         ((u64) dd->ipath_pkeys[3] << 48);
682                 ipath_cdbg(VERBOSE, "p%u old pkey reg %llx, "
683                            "new pkey reg %llx\n", pd->port_port,
684                            (unsigned long long) oldpkey,
685                            (unsigned long long) pkey);
686                 ipath_write_kreg(dd, dd->ipath_kregs->kr_partitionkey,
687                                  pkey);
688         }
689 }
690
691 /**
692  * ipath_create_user_egr - allocate eager TID buffers
693  * @pd: the port to allocate TID buffers for
694  *
695  * This routine is now quite different for user and kernel, because
696  * the kernel uses skb's, for the accelerated network performance
697  * This is the user port version
698  *
699  * Allocate the eager TID buffers and program them into infinipath
700  * They are no longer completely contiguous, we do multiple allocation
701  * calls.
702  */
703 static int ipath_create_user_egr(struct ipath_portdata *pd)
704 {
705         struct ipath_devdata *dd = pd->port_dd;
706         unsigned e, egrcnt, alloced, egrperchunk, chunk, egrsize, egroff;
707         size_t size;
708         int ret;
709         gfp_t gfp_flags;
710
711         /*
712          * GFP_USER, but without GFP_FS, so buffer cache can be
713          * coalesced (we hope); otherwise, even at order 4,
714          * heavy filesystem activity makes these fail, and we can
715          * use compound pages.
716          */
717         gfp_flags = __GFP_WAIT | __GFP_IO | __GFP_COMP;
718
719         egrcnt = dd->ipath_rcvegrcnt;
720         /* TID number offset for this port */
721         egroff = pd->port_port * egrcnt;
722         egrsize = dd->ipath_rcvegrbufsize;
723         ipath_cdbg(VERBOSE, "Allocating %d egr buffers, at egrtid "
724                    "offset %x, egrsize %u\n", egrcnt, egroff, egrsize);
725
726         /*
727          * to avoid wasting a lot of memory, we allocate 32KB chunks of
728          * physically contiguous memory, advance through it until used up
729          * and then allocate more.  Of course, we need memory to store those
730          * extra pointers, now.  Started out with 256KB, but under heavy
731          * memory pressure (creating large files and then copying them over
732          * NFS while doing lots of MPI jobs), we hit some allocation
733          * failures, even though we can sleep...  (2.6.10) Still get
734          * failures at 64K.  32K is the lowest we can go without wasting
735          * additional memory.
736          */
737         size = 0x8000;
738         alloced = ALIGN(egrsize * egrcnt, size);
739         egrperchunk = size / egrsize;
740         chunk = (egrcnt + egrperchunk - 1) / egrperchunk;
741         pd->port_rcvegrbuf_chunks = chunk;
742         pd->port_rcvegrbufs_perchunk = egrperchunk;
743         pd->port_rcvegrbuf_size = size;
744         pd->port_rcvegrbuf = vmalloc(chunk * sizeof(pd->port_rcvegrbuf[0]));
745         if (!pd->port_rcvegrbuf) {
746                 ret = -ENOMEM;
747                 goto bail;
748         }
749         pd->port_rcvegrbuf_phys =
750                 vmalloc(chunk * sizeof(pd->port_rcvegrbuf_phys[0]));
751         if (!pd->port_rcvegrbuf_phys) {
752                 ret = -ENOMEM;
753                 goto bail_rcvegrbuf;
754         }
755         for (e = 0; e < pd->port_rcvegrbuf_chunks; e++) {
756
757                 pd->port_rcvegrbuf[e] = dma_alloc_coherent(
758                         &dd->pcidev->dev, size, &pd->port_rcvegrbuf_phys[e],
759                         gfp_flags);
760
761                 if (!pd->port_rcvegrbuf[e]) {
762                         ret = -ENOMEM;
763                         goto bail_rcvegrbuf_phys;
764                 }
765         }
766
767         pd->port_rcvegr_phys = pd->port_rcvegrbuf_phys[0];
768
769         for (e = chunk = 0; chunk < pd->port_rcvegrbuf_chunks; chunk++) {
770                 dma_addr_t pa = pd->port_rcvegrbuf_phys[chunk];
771                 unsigned i;
772
773                 for (i = 0; e < egrcnt && i < egrperchunk; e++, i++) {
774                         dd->ipath_f_put_tid(dd, e + egroff +
775                                             (u64 __iomem *)
776                                             ((char __iomem *)
777                                              dd->ipath_kregbase +
778                                              dd->ipath_rcvegrbase), 0, pa);
779                         pa += egrsize;
780                 }
781                 cond_resched(); /* don't hog the cpu */
782         }
783
784         ret = 0;
785         goto bail;
786
787 bail_rcvegrbuf_phys:
788         for (e = 0; e < pd->port_rcvegrbuf_chunks &&
789                 pd->port_rcvegrbuf[e]; e++) {
790                 dma_free_coherent(&dd->pcidev->dev, size,
791                                   pd->port_rcvegrbuf[e],
792                                   pd->port_rcvegrbuf_phys[e]);
793
794         }
795         vfree(pd->port_rcvegrbuf_phys);
796         pd->port_rcvegrbuf_phys = NULL;
797 bail_rcvegrbuf:
798         vfree(pd->port_rcvegrbuf);
799         pd->port_rcvegrbuf = NULL;
800 bail:
801         return ret;
802 }
803
804 static int ipath_do_user_init(struct ipath_portdata *pd,
805                               const struct ipath_user_info *uinfo)
806 {
807         int ret = 0;
808         struct ipath_devdata *dd = pd->port_dd;
809         u32 head32;
810
811         /* for now, if major version is different, bail */
812         if ((uinfo->spu_userversion >> 16) != IPATH_USER_SWMAJOR) {
813                 dev_info(&dd->pcidev->dev,
814                          "User major version %d not same as driver "
815                          "major %d\n", uinfo->spu_userversion >> 16,
816                          IPATH_USER_SWMAJOR);
817                 ret = -ENODEV;
818                 goto done;
819         }
820
821         if ((uinfo->spu_userversion & 0xffff) != IPATH_USER_SWMINOR)
822                 ipath_dbg("User minor version %d not same as driver "
823                           "minor %d\n", uinfo->spu_userversion & 0xffff,
824                           IPATH_USER_SWMINOR);
825
826         if (uinfo->spu_rcvhdrsize) {
827                 ret = ipath_setrcvhdrsize(dd, uinfo->spu_rcvhdrsize);
828                 if (ret)
829                         goto done;
830         }
831
832         /* for now we do nothing with rcvhdrcnt: uinfo->spu_rcvhdrcnt */
833
834         /* for right now, kernel piobufs are at end, so port 1 is at 0 */
835         pd->port_piobufs = dd->ipath_piobufbase +
836                 dd->ipath_pbufsport * (pd->port_port -
837                                        1) * dd->ipath_palign;
838         ipath_cdbg(VERBOSE, "Set base of piobufs for port %u to 0x%x\n",
839                    pd->port_port, pd->port_piobufs);
840
841         /*
842          * Now allocate the rcvhdr Q and eager TIDs; skip the TID
843          * array for time being.  If pd->port_port > chip-supported,
844          * we need to do extra stuff here to handle by handling overflow
845          * through port 0, someday
846          */
847         ret = ipath_create_rcvhdrq(dd, pd);
848         if (!ret)
849                 ret = ipath_create_user_egr(pd);
850         if (ret)
851                 goto done;
852
853         /*
854          * set the eager head register for this port to the current values
855          * of the tail pointers, since we don't know if they were
856          * updated on last use of the port.
857          */
858         head32 = ipath_read_ureg32(dd, ur_rcvegrindextail, pd->port_port);
859         ipath_write_ureg(dd, ur_rcvegrindexhead, head32, pd->port_port);
860         dd->ipath_lastegrheads[pd->port_port] = -1;
861         dd->ipath_lastrcvhdrqtails[pd->port_port] = -1;
862         ipath_cdbg(VERBOSE, "Wrote port%d egrhead %x from tail regs\n",
863                 pd->port_port, head32);
864         pd->port_tidcursor = 0; /* start at beginning after open */
865         /*
866          * now enable the port; the tail registers will be written to memory
867          * by the chip as soon as it sees the write to
868          * dd->ipath_kregs->kr_rcvctrl.  The update only happens on
869          * transition from 0 to 1, so clear it first, then set it as part of
870          * enabling the port.  This will (very briefly) affect any other
871          * open ports, but it shouldn't be long enough to be an issue.
872          * We explictly set the in-memory copy to 0 beforehand, so we don't
873          * have to wait to be sure the DMA update has happened.
874          */
875         *pd->port_rcvhdrtail_kvaddr = 0ULL;
876         set_bit(INFINIPATH_R_PORTENABLE_SHIFT + pd->port_port,
877                 &dd->ipath_rcvctrl);
878         ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
879                          dd->ipath_rcvctrl & ~INFINIPATH_R_TAILUPD);
880         ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
881                          dd->ipath_rcvctrl);
882 done:
883         return ret;
884 }
885
886
887 /* common code for the mappings on dma_alloc_coherent mem */
888 static int ipath_mmap_mem(struct vm_area_struct *vma,
889                              struct ipath_portdata *pd, unsigned len,
890                              int write_ok, dma_addr_t addr, char *what)
891 {
892         struct ipath_devdata *dd = pd->port_dd;
893         unsigned pfn = (unsigned long)addr >> PAGE_SHIFT;
894         int ret;
895
896         if ((vma->vm_end - vma->vm_start) > len) {
897                 dev_info(&dd->pcidev->dev,
898                          "FAIL on %s: len %lx > %x\n", what,
899                          vma->vm_end - vma->vm_start, len);
900                 ret = -EFAULT;
901                 goto bail;
902         }
903
904         if (!write_ok) {
905                 if (vma->vm_flags & VM_WRITE) {
906                         dev_info(&dd->pcidev->dev,
907                                  "%s must be mapped readonly\n", what);
908                         ret = -EPERM;
909                         goto bail;
910                 }
911
912                 /* don't allow them to later change with mprotect */
913                 vma->vm_flags &= ~VM_MAYWRITE;
914         }
915
916         ret = remap_pfn_range(vma, vma->vm_start, pfn,
917                               len, vma->vm_page_prot);
918         if (ret)
919                 dev_info(&dd->pcidev->dev,
920                          "%s port%u mmap of %lx, %x bytes r%c failed: %d\n",
921                          what, pd->port_port, (unsigned long)addr, len,
922                          write_ok?'w':'o', ret);
923         else
924                 ipath_cdbg(VERBOSE, "%s port%u mmaped %lx, %x bytes r%c\n",
925                         what, pd->port_port, (unsigned long)addr, len,
926                          write_ok?'w':'o');
927 bail:
928         return ret;
929 }
930
931 static int mmap_ureg(struct vm_area_struct *vma, struct ipath_devdata *dd,
932                      u64 ureg)
933 {
934         unsigned long phys;
935         int ret;
936
937         /*
938          * This is real hardware, so use io_remap.  This is the mechanism
939          * for the user process to update the head registers for their port
940          * in the chip.
941          */
942         if ((vma->vm_end - vma->vm_start) > PAGE_SIZE) {
943                 dev_info(&dd->pcidev->dev, "FAIL mmap userreg: reqlen "
944                          "%lx > PAGE\n", vma->vm_end - vma->vm_start);
945                 ret = -EFAULT;
946         } else {
947                 phys = dd->ipath_physaddr + ureg;
948                 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
949
950                 vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;
951                 ret = io_remap_pfn_range(vma, vma->vm_start,
952                                          phys >> PAGE_SHIFT,
953                                          vma->vm_end - vma->vm_start,
954                                          vma->vm_page_prot);
955         }
956         return ret;
957 }
958
959 static int mmap_piobufs(struct vm_area_struct *vma,
960                         struct ipath_devdata *dd,
961                         struct ipath_portdata *pd)
962 {
963         unsigned long phys;
964         int ret;
965
966         /*
967          * When we map the PIO buffers in the chip, we want to map them as
968          * writeonly, no read possible.   This prevents access to previous
969          * process data, and catches users who might try to read the i/o
970          * space due to a bug.
971          */
972         if ((vma->vm_end - vma->vm_start) >
973             (dd->ipath_pbufsport * dd->ipath_palign)) {
974                 dev_info(&dd->pcidev->dev, "FAIL mmap piobufs: "
975                          "reqlen %lx > PAGE\n",
976                          vma->vm_end - vma->vm_start);
977                 ret = -EFAULT;
978                 goto bail;
979         }
980
981         phys = dd->ipath_physaddr + pd->port_piobufs;
982
983         /*
984          * Don't mark this as non-cached, or we don't get the
985          * write combining behavior we want on the PIO buffers!
986          */
987
988         if (vma->vm_flags & VM_READ) {
989                 dev_info(&dd->pcidev->dev,
990                          "Can't map piobufs as readable (flags=%lx)\n",
991                          vma->vm_flags);
992                 ret = -EPERM;
993                 goto bail;
994         }
995
996         /* don't allow them to later change to readable with mprotect */
997         vma->vm_flags &= ~VM_MAYREAD;
998         vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;
999
1000         ret = io_remap_pfn_range(vma, vma->vm_start, phys >> PAGE_SHIFT,
1001                                  vma->vm_end - vma->vm_start,
1002                                  vma->vm_page_prot);
1003 bail:
1004         return ret;
1005 }
1006
1007 static int mmap_rcvegrbufs(struct vm_area_struct *vma,
1008                            struct ipath_portdata *pd)
1009 {
1010         struct ipath_devdata *dd = pd->port_dd;
1011         unsigned long start, size;
1012         size_t total_size, i;
1013         dma_addr_t *phys;
1014         int ret;
1015
1016         size = pd->port_rcvegrbuf_size;
1017         total_size = pd->port_rcvegrbuf_chunks * size;
1018         if ((vma->vm_end - vma->vm_start) > total_size) {
1019                 dev_info(&dd->pcidev->dev, "FAIL on egr bufs: "
1020                          "reqlen %lx > actual %lx\n",
1021                          vma->vm_end - vma->vm_start,
1022                          (unsigned long) total_size);
1023                 ret = -EFAULT;
1024                 goto bail;
1025         }
1026
1027         if (vma->vm_flags & VM_WRITE) {
1028                 dev_info(&dd->pcidev->dev, "Can't map eager buffers as "
1029                          "writable (flags=%lx)\n", vma->vm_flags);
1030                 ret = -EPERM;
1031                 goto bail;
1032         }
1033         /* don't allow them to later change to writeable with mprotect */
1034         vma->vm_flags &= ~VM_MAYWRITE;
1035
1036         start = vma->vm_start;
1037         phys = pd->port_rcvegrbuf_phys;
1038
1039         for (i = 0; i < pd->port_rcvegrbuf_chunks; i++, start += size) {
1040                 ret = remap_pfn_range(vma, start, phys[i] >> PAGE_SHIFT,
1041                                       size, vma->vm_page_prot);
1042                 if (ret < 0)
1043                         goto bail;
1044         }
1045         ret = 0;
1046
1047 bail:
1048         return ret;
1049 }
1050
1051 /**
1052  * ipath_mmap - mmap various structures into user space
1053  * @fp: the file pointer
1054  * @vma: the VM area
1055  *
1056  * We use this to have a shared buffer between the kernel and the user code
1057  * for the rcvhdr queue, egr buffers, and the per-port user regs and pio
1058  * buffers in the chip.  We have the open and close entries so we can bump
1059  * the ref count and keep the driver from being unloaded while still mapped.
1060  */
1061 static int ipath_mmap(struct file *fp, struct vm_area_struct *vma)
1062 {
1063         struct ipath_portdata *pd;
1064         struct ipath_devdata *dd;
1065         u64 pgaddr, ureg;
1066         int ret;
1067
1068         pd = port_fp(fp);
1069         dd = pd->port_dd;
1070
1071         /*
1072          * This is the ipath_do_user_init() code, mapping the shared buffers
1073          * into the user process. The address referred to by vm_pgoff is the
1074          * virtual, not physical, address; we only do one mmap for each
1075          * space mapped.
1076          */
1077         pgaddr = vma->vm_pgoff << PAGE_SHIFT;
1078
1079         /*
1080          * Must fit in 40 bits for our hardware; some checked elsewhere,
1081          * but we'll be paranoid.  Check for 0 is mostly in case one of the
1082          * allocations failed, but user called mmap anyway.   We want to catch
1083          * that before it can match.
1084          */
1085         if (!pgaddr || pgaddr >= (1ULL<<40))  {
1086                 ipath_dev_err(dd, "Bad phys addr %llx, start %lx, end %lx\n",
1087                         (unsigned long long)pgaddr, vma->vm_start, vma->vm_end);
1088                 return -EINVAL;
1089         }
1090
1091         /* just the offset of the port user registers, not physical addr */
1092         ureg = dd->ipath_uregbase + dd->ipath_palign * pd->port_port;
1093
1094         ipath_cdbg(MM, "ushare: pgaddr %llx vm_start=%lx, vmlen %lx\n",
1095                    (unsigned long long) pgaddr, vma->vm_start,
1096                    vma->vm_end - vma->vm_start);
1097
1098         if (vma->vm_start & (PAGE_SIZE-1)) {
1099                 ipath_dev_err(dd,
1100                         "vm_start not aligned: %lx, end=%lx phys %lx\n",
1101                         vma->vm_start, vma->vm_end, (unsigned long)pgaddr);
1102                 ret = -EINVAL;
1103         }
1104         else if (pgaddr == ureg)
1105                 ret = mmap_ureg(vma, dd, ureg);
1106         else if (pgaddr == pd->port_piobufs)
1107                 ret = mmap_piobufs(vma, dd, pd);
1108         else if (pgaddr == (u64) pd->port_rcvegr_phys)
1109                 ret = mmap_rcvegrbufs(vma, pd);
1110         else if (pgaddr == (u64) pd->port_rcvhdrq_phys) {
1111                 /*
1112                  * The rcvhdrq itself; readonly except on HT-400 (so have
1113                  * to allow writable mapping), multiple pages, contiguous
1114                  * from an i/o perspective.
1115                  */
1116                 unsigned total_size =
1117                         ALIGN(dd->ipath_rcvhdrcnt * dd->ipath_rcvhdrentsize
1118                            * sizeof(u32), PAGE_SIZE);
1119                 ret = ipath_mmap_mem(vma, pd, total_size, 1,
1120                                      pd->port_rcvhdrq_phys,
1121                                      "rcvhdrq");
1122         }
1123         else if (pgaddr == (u64)pd->port_rcvhdrqtailaddr_phys)
1124                 /* in-memory copy of rcvhdrq tail register */
1125                 ret = ipath_mmap_mem(vma, pd, PAGE_SIZE, 0,
1126                                      pd->port_rcvhdrqtailaddr_phys,
1127                                      "rcvhdrq tail");
1128         else if (pgaddr == dd->ipath_pioavailregs_phys)
1129                 /* in-memory copy of pioavail registers */
1130                 ret = ipath_mmap_mem(vma, pd, PAGE_SIZE, 0,
1131                                      dd->ipath_pioavailregs_phys,
1132                                      "pioavail registers");
1133         else
1134                 ret = -EINVAL;
1135
1136         vma->vm_private_data = NULL;
1137
1138         if (ret < 0)
1139                 dev_info(&dd->pcidev->dev,
1140                          "Failure %d on addr %lx, off %lx\n",
1141                          -ret, vma->vm_start, vma->vm_pgoff);
1142
1143         return ret;
1144 }
1145
1146 static unsigned int ipath_poll(struct file *fp,
1147                                struct poll_table_struct *pt)
1148 {
1149         struct ipath_portdata *pd;
1150         u32 head, tail;
1151         int bit;
1152         struct ipath_devdata *dd;
1153
1154         pd = port_fp(fp);
1155         dd = pd->port_dd;
1156
1157         bit = pd->port_port + INFINIPATH_R_INTRAVAIL_SHIFT;
1158         set_bit(bit, &dd->ipath_rcvctrl);
1159
1160         /*
1161          * Before blocking, make sure that head is still == tail,
1162          * reading from the chip, so we can be sure the interrupt
1163          * enable has made it to the chip.  If not equal, disable
1164          * interrupt again and return immediately.  This avoids races,
1165          * and the overhead of the chip read doesn't matter much at
1166          * this point, since we are waiting for something anyway.
1167          */
1168
1169         ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
1170                          dd->ipath_rcvctrl);
1171
1172         head = ipath_read_ureg32(dd, ur_rcvhdrhead, pd->port_port);
1173         tail = ipath_read_ureg32(dd, ur_rcvhdrtail, pd->port_port);
1174
1175         if (tail == head) {
1176                 set_bit(IPATH_PORT_WAITING_RCV, &pd->port_flag);
1177                 if(dd->ipath_rhdrhead_intr_off) /* arm rcv interrupt */
1178                         (void)ipath_write_ureg(dd, ur_rcvhdrhead,
1179                                                dd->ipath_rhdrhead_intr_off
1180                                                | head, pd->port_port);
1181                 poll_wait(fp, &pd->port_wait, pt);
1182
1183                 if (test_bit(IPATH_PORT_WAITING_RCV, &pd->port_flag)) {
1184                         /* timed out, no packets received */
1185                         clear_bit(IPATH_PORT_WAITING_RCV, &pd->port_flag);
1186                         pd->port_rcvwait_to++;
1187                 }
1188         }
1189         else {
1190                 /* it's already happened; don't do wait_event overhead */
1191                 pd->port_rcvnowait++;
1192         }
1193
1194         clear_bit(bit, &dd->ipath_rcvctrl);
1195         ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
1196                          dd->ipath_rcvctrl);
1197
1198         return 0;
1199 }
1200
1201 static int try_alloc_port(struct ipath_devdata *dd, int port,
1202                           struct file *fp)
1203 {
1204         int ret;
1205
1206         if (!dd->ipath_pd[port]) {
1207                 void *p, *ptmp;
1208
1209                 p = kzalloc(sizeof(struct ipath_portdata), GFP_KERNEL);
1210
1211                 /*
1212                  * Allocate memory for use in ipath_tid_update() just once
1213                  * at open, not per call.  Reduces cost of expected send
1214                  * setup.
1215                  */
1216                 ptmp = kmalloc(dd->ipath_rcvtidcnt * sizeof(u16) +
1217                                dd->ipath_rcvtidcnt * sizeof(struct page **),
1218                                GFP_KERNEL);
1219                 if (!p || !ptmp) {
1220                         ipath_dev_err(dd, "Unable to allocate portdata "
1221                                       "memory, failing open\n");
1222                         ret = -ENOMEM;
1223                         kfree(p);
1224                         kfree(ptmp);
1225                         goto bail;
1226                 }
1227                 dd->ipath_pd[port] = p;
1228                 dd->ipath_pd[port]->port_port = port;
1229                 dd->ipath_pd[port]->port_dd = dd;
1230                 dd->ipath_pd[port]->port_tid_pg_list = ptmp;
1231                 init_waitqueue_head(&dd->ipath_pd[port]->port_wait);
1232         }
1233         if (!dd->ipath_pd[port]->port_cnt) {
1234                 dd->ipath_pd[port]->port_cnt = 1;
1235                 fp->private_data = (void *) dd->ipath_pd[port];
1236                 ipath_cdbg(PROC, "%s[%u] opened unit:port %u:%u\n",
1237                            current->comm, current->pid, dd->ipath_unit,
1238                            port);
1239                 dd->ipath_pd[port]->port_pid = current->pid;
1240                 strncpy(dd->ipath_pd[port]->port_comm, current->comm,
1241                         sizeof(dd->ipath_pd[port]->port_comm));
1242                 ipath_stats.sps_ports++;
1243                 ret = 0;
1244                 goto bail;
1245         }
1246         ret = -EBUSY;
1247
1248 bail:
1249         return ret;
1250 }
1251
1252 static inline int usable(struct ipath_devdata *dd)
1253 {
1254         return dd &&
1255                 (dd->ipath_flags & IPATH_PRESENT) &&
1256                 dd->ipath_kregbase &&
1257                 dd->ipath_lid &&
1258                 !(dd->ipath_flags & (IPATH_LINKDOWN | IPATH_DISABLED
1259                                      | IPATH_LINKUNK));
1260 }
1261
1262 static int find_free_port(int unit, struct file *fp)
1263 {
1264         struct ipath_devdata *dd = ipath_lookup(unit);
1265         int ret, i;
1266
1267         if (!dd) {
1268                 ret = -ENODEV;
1269                 goto bail;
1270         }
1271
1272         if (!usable(dd)) {
1273                 ret = -ENETDOWN;
1274                 goto bail;
1275         }
1276
1277         for (i = 0; i < dd->ipath_cfgports; i++) {
1278                 ret = try_alloc_port(dd, i, fp);
1279                 if (ret != -EBUSY)
1280                         goto bail;
1281         }
1282         ret = -EBUSY;
1283
1284 bail:
1285         return ret;
1286 }
1287
1288 static int find_best_unit(struct file *fp)
1289 {
1290         int ret = 0, i, prefunit = -1, devmax;
1291         int maxofallports, npresent, nup;
1292         int ndev;
1293
1294         (void) ipath_count_units(&npresent, &nup, &maxofallports);
1295
1296         /*
1297          * This code is present to allow a knowledgeable person to
1298          * specify the layout of processes to processors before opening
1299          * this driver, and then we'll assign the process to the "closest"
1300          * HT-400 to that processor (we assume reasonable connectivity,
1301          * for now).  This code assumes that if affinity has been set
1302          * before this point, that at most one cpu is set; for now this
1303          * is reasonable.  I check for both cpus_empty() and cpus_full(),
1304          * in case some kernel variant sets none of the bits when no
1305          * affinity is set.  2.6.11 and 12 kernels have all present
1306          * cpus set.  Some day we'll have to fix it up further to handle
1307          * a cpu subset.  This algorithm fails for two HT-400's connected
1308          * in tunnel fashion.  Eventually this needs real topology
1309          * information.  There may be some issues with dual core numbering
1310          * as well.  This needs more work prior to release.
1311          */
1312         if (!cpus_empty(current->cpus_allowed) &&
1313             !cpus_full(current->cpus_allowed)) {
1314                 int ncpus = num_online_cpus(), curcpu = -1;
1315                 for (i = 0; i < ncpus; i++)
1316                         if (cpu_isset(i, current->cpus_allowed)) {
1317                                 ipath_cdbg(PROC, "%s[%u] affinity set for "
1318                                            "cpu %d\n", current->comm,
1319                                            current->pid, i);
1320                                 curcpu = i;
1321                         }
1322                 if (curcpu != -1) {
1323                         if (npresent) {
1324                                 prefunit = curcpu / (ncpus / npresent);
1325                                 ipath_dbg("%s[%u] %d chips, %d cpus, "
1326                                           "%d cpus/chip, select unit %d\n",
1327                                           current->comm, current->pid,
1328                                           npresent, ncpus, ncpus / npresent,
1329                                           prefunit);
1330                         }
1331                 }
1332         }
1333
1334         /*
1335          * user ports start at 1, kernel port is 0
1336          * For now, we do round-robin access across all chips
1337          */
1338
1339         if (prefunit != -1)
1340                 devmax = prefunit + 1;
1341         else
1342                 devmax = ipath_count_units(NULL, NULL, NULL);
1343 recheck:
1344         for (i = 1; i < maxofallports; i++) {
1345                 for (ndev = prefunit != -1 ? prefunit : 0; ndev < devmax;
1346                      ndev++) {
1347                         struct ipath_devdata *dd = ipath_lookup(ndev);
1348
1349                         if (!usable(dd))
1350                                 continue; /* can't use this unit */
1351                         if (i >= dd->ipath_cfgports)
1352                                 /*
1353                                  * Maxed out on users of this unit. Try
1354                                  * next.
1355                                  */
1356                                 continue;
1357                         ret = try_alloc_port(dd, i, fp);
1358                         if (!ret)
1359                                 goto done;
1360                 }
1361         }
1362
1363         if (npresent) {
1364                 if (nup == 0) {
1365                         ret = -ENETDOWN;
1366                         ipath_dbg("No ports available (none initialized "
1367                                   "and ready)\n");
1368                 } else {
1369                         if (prefunit > 0) {
1370                                 /* if started above 0, retry from 0 */
1371                                 ipath_cdbg(PROC,
1372                                            "%s[%u] no ports on prefunit "
1373                                            "%d, clear and re-check\n",
1374                                            current->comm, current->pid,
1375                                            prefunit);
1376                                 devmax = ipath_count_units(NULL, NULL,
1377                                                            NULL);
1378                                 prefunit = -1;
1379                                 goto recheck;
1380                         }
1381                         ret = -EBUSY;
1382                         ipath_dbg("No ports available\n");
1383                 }
1384         } else {
1385                 ret = -ENXIO;
1386                 ipath_dbg("No boards found\n");
1387         }
1388
1389 done:
1390         return ret;
1391 }
1392
1393 static int ipath_open(struct inode *in, struct file *fp)
1394 {
1395         int ret, user_minor;
1396
1397         mutex_lock(&ipath_mutex);
1398
1399         user_minor = iminor(in) - IPATH_USER_MINOR_BASE;
1400         ipath_cdbg(VERBOSE, "open on dev %lx (minor %d)\n",
1401                    (long)in->i_rdev, user_minor);
1402
1403         if (user_minor)
1404                 ret = find_free_port(user_minor - 1, fp);
1405         else
1406                 ret = find_best_unit(fp);
1407
1408         mutex_unlock(&ipath_mutex);
1409         return ret;
1410 }
1411
1412 /**
1413  * unlock_exptid - unlock any expected TID entries port still had in use
1414  * @pd: port
1415  *
1416  * We don't actually update the chip here, because we do a bulk update
1417  * below, using ipath_f_clear_tids.
1418  */
1419 static void unlock_expected_tids(struct ipath_portdata *pd)
1420 {
1421         struct ipath_devdata *dd = pd->port_dd;
1422         int port_tidbase = pd->port_port * dd->ipath_rcvtidcnt;
1423         int i, cnt = 0, maxtid = port_tidbase + dd->ipath_rcvtidcnt;
1424
1425         ipath_cdbg(VERBOSE, "Port %u unlocking any locked expTID pages\n",
1426                    pd->port_port);
1427         for (i = port_tidbase; i < maxtid; i++) {
1428                 if (!dd->ipath_pageshadow[i])
1429                         continue;
1430
1431                 ipath_release_user_pages_on_close(&dd->ipath_pageshadow[i],
1432                                                   1);
1433                 dd->ipath_pageshadow[i] = NULL;
1434                 cnt++;
1435                 ipath_stats.sps_pageunlocks++;
1436         }
1437         if (cnt)
1438                 ipath_cdbg(VERBOSE, "Port %u locked %u expTID entries\n",
1439                            pd->port_port, cnt);
1440
1441         if (ipath_stats.sps_pagelocks || ipath_stats.sps_pageunlocks)
1442                 ipath_cdbg(VERBOSE, "%llu pages locked, %llu unlocked\n",
1443                            (unsigned long long) ipath_stats.sps_pagelocks,
1444                            (unsigned long long)
1445                            ipath_stats.sps_pageunlocks);
1446 }
1447
1448 static int ipath_close(struct inode *in, struct file *fp)
1449 {
1450         int ret = 0;
1451         struct ipath_portdata *pd;
1452         struct ipath_devdata *dd;
1453         unsigned port;
1454
1455         ipath_cdbg(VERBOSE, "close on dev %lx, private data %p\n",
1456                    (long)in->i_rdev, fp->private_data);
1457
1458         mutex_lock(&ipath_mutex);
1459
1460         pd = port_fp(fp);
1461         port = pd->port_port;
1462         fp->private_data = NULL;
1463         dd = pd->port_dd;
1464
1465         if (pd->port_hdrqfull) {
1466                 ipath_cdbg(PROC, "%s[%u] had %u rcvhdrqfull errors "
1467                            "during run\n", pd->port_comm, pd->port_pid,
1468                            pd->port_hdrqfull);
1469                 pd->port_hdrqfull = 0;
1470         }
1471
1472         if (pd->port_rcvwait_to || pd->port_piowait_to
1473             || pd->port_rcvnowait || pd->port_pionowait) {
1474                 ipath_cdbg(VERBOSE, "port%u, %u rcv, %u pio wait timeo; "
1475                            "%u rcv %u, pio already\n",
1476                            pd->port_port, pd->port_rcvwait_to,
1477                            pd->port_piowait_to, pd->port_rcvnowait,
1478                            pd->port_pionowait);
1479                 pd->port_rcvwait_to = pd->port_piowait_to =
1480                         pd->port_rcvnowait = pd->port_pionowait = 0;
1481         }
1482         if (pd->port_flag) {
1483                 ipath_dbg("port %u port_flag still set to 0x%lx\n",
1484                           pd->port_port, pd->port_flag);
1485                 pd->port_flag = 0;
1486         }
1487
1488         if (dd->ipath_kregbase) {
1489                 int i;
1490                 /* atomically clear receive enable port. */
1491                 clear_bit(INFINIPATH_R_PORTENABLE_SHIFT + port,
1492                           &dd->ipath_rcvctrl);
1493                 ipath_write_kreg( dd, dd->ipath_kregs->kr_rcvctrl,
1494                         dd->ipath_rcvctrl);
1495                 /* and read back from chip to be sure that nothing
1496                  * else is in flight when we do the rest */
1497                 (void)ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
1498
1499                 /* clean up the pkeys for this port user */
1500                 ipath_clean_part_key(pd, dd);
1501
1502
1503                 /*
1504                  * be paranoid, and never write 0's to these, just use an
1505                  * unused part of the port 0 tail page.  Of course,
1506                  * rcvhdraddr points to a large chunk of memory, so this
1507                  * could still trash things, but at least it won't trash
1508                  * page 0, and by disabling the port, it should stop "soon",
1509                  * even if a packet or two is in already in flight after we
1510                  * disabled the port.
1511                  */
1512                 ipath_write_kreg_port(dd,
1513                         dd->ipath_kregs->kr_rcvhdrtailaddr, port,
1514                         dd->ipath_dummy_hdrq_phys);
1515                 ipath_write_kreg_port(dd, dd->ipath_kregs->kr_rcvhdraddr,
1516                         pd->port_port, dd->ipath_dummy_hdrq_phys);
1517
1518                 i = dd->ipath_pbufsport * (port - 1);
1519                 ipath_disarm_piobufs(dd, i, dd->ipath_pbufsport);
1520
1521                 if (dd->ipath_pageshadow)
1522                         unlock_expected_tids(pd);
1523                 ipath_stats.sps_ports--;
1524                 ipath_cdbg(PROC, "%s[%u] closed port %u:%u\n",
1525                            pd->port_comm, pd->port_pid,
1526                            dd->ipath_unit, port);
1527
1528                 dd->ipath_f_clear_tids(dd, pd->port_port);
1529         }
1530
1531         pd->port_cnt = 0;
1532         pd->port_pid = 0;
1533
1534         dd->ipath_pd[pd->port_port] = NULL; /* before releasing mutex */
1535         mutex_unlock(&ipath_mutex);
1536         ipath_free_pddata(dd, pd); /* after releasing the mutex */
1537
1538         return ret;
1539 }
1540
1541 static int ipath_port_info(struct ipath_portdata *pd,
1542                            struct ipath_port_info __user *uinfo)
1543 {
1544         struct ipath_port_info info;
1545         int nup;
1546         int ret;
1547
1548         (void) ipath_count_units(NULL, &nup, NULL);
1549         info.num_active = nup;
1550         info.unit = pd->port_dd->ipath_unit;
1551         info.port = pd->port_port;
1552
1553         if (copy_to_user(uinfo, &info, sizeof(info))) {
1554                 ret = -EFAULT;
1555                 goto bail;
1556         }
1557         ret = 0;
1558
1559 bail:
1560         return ret;
1561 }
1562
1563 static ssize_t ipath_write(struct file *fp, const char __user *data,
1564                            size_t count, loff_t *off)
1565 {
1566         const struct ipath_cmd __user *ucmd;
1567         struct ipath_portdata *pd;
1568         const void __user *src;
1569         size_t consumed, copy;
1570         struct ipath_cmd cmd;
1571         ssize_t ret = 0;
1572         void *dest;
1573
1574         if (count < sizeof(cmd.type)) {
1575                 ret = -EINVAL;
1576                 goto bail;
1577         }
1578
1579         ucmd = (const struct ipath_cmd __user *) data;
1580
1581         if (copy_from_user(&cmd.type, &ucmd->type, sizeof(cmd.type))) {
1582                 ret = -EFAULT;
1583                 goto bail;
1584         }
1585
1586         consumed = sizeof(cmd.type);
1587
1588         switch (cmd.type) {
1589         case IPATH_CMD_USER_INIT:
1590                 copy = sizeof(cmd.cmd.user_info);
1591                 dest = &cmd.cmd.user_info;
1592                 src = &ucmd->cmd.user_info;
1593                 break;
1594         case IPATH_CMD_RECV_CTRL:
1595                 copy = sizeof(cmd.cmd.recv_ctrl);
1596                 dest = &cmd.cmd.recv_ctrl;
1597                 src = &ucmd->cmd.recv_ctrl;
1598                 break;
1599         case IPATH_CMD_PORT_INFO:
1600                 copy = sizeof(cmd.cmd.port_info);
1601                 dest = &cmd.cmd.port_info;
1602                 src = &ucmd->cmd.port_info;
1603                 break;
1604         case IPATH_CMD_TID_UPDATE:
1605         case IPATH_CMD_TID_FREE:
1606                 copy = sizeof(cmd.cmd.tid_info);
1607                 dest = &cmd.cmd.tid_info;
1608                 src = &ucmd->cmd.tid_info;
1609                 break;
1610         case IPATH_CMD_SET_PART_KEY:
1611                 copy = sizeof(cmd.cmd.part_key);
1612                 dest = &cmd.cmd.part_key;
1613                 src = &ucmd->cmd.part_key;
1614                 break;
1615         default:
1616                 ret = -EINVAL;
1617                 goto bail;
1618         }
1619
1620         if ((count - consumed) < copy) {
1621                 ret = -EINVAL;
1622                 goto bail;
1623         }
1624
1625         if (copy_from_user(dest, src, copy)) {
1626                 ret = -EFAULT;
1627                 goto bail;
1628         }
1629
1630         consumed += copy;
1631         pd = port_fp(fp);
1632
1633         switch (cmd.type) {
1634         case IPATH_CMD_USER_INIT:
1635                 ret = ipath_do_user_init(pd, &cmd.cmd.user_info);
1636                 if (ret < 0)
1637                         goto bail;
1638                 ret = ipath_get_base_info(
1639                         pd, (void __user *) (unsigned long)
1640                         cmd.cmd.user_info.spu_base_info,
1641                         cmd.cmd.user_info.spu_base_info_size);
1642                 break;
1643         case IPATH_CMD_RECV_CTRL:
1644                 ret = ipath_manage_rcvq(pd, cmd.cmd.recv_ctrl);
1645                 break;
1646         case IPATH_CMD_PORT_INFO:
1647                 ret = ipath_port_info(pd,
1648                                       (struct ipath_port_info __user *)
1649                                       (unsigned long) cmd.cmd.port_info);
1650                 break;
1651         case IPATH_CMD_TID_UPDATE:
1652                 ret = ipath_tid_update(pd, &cmd.cmd.tid_info);
1653                 break;
1654         case IPATH_CMD_TID_FREE:
1655                 ret = ipath_tid_free(pd, &cmd.cmd.tid_info);
1656                 break;
1657         case IPATH_CMD_SET_PART_KEY:
1658                 ret = ipath_set_part_key(pd, cmd.cmd.part_key);
1659                 break;
1660         }
1661
1662         if (ret >= 0)
1663                 ret = consumed;
1664
1665 bail:
1666         return ret;
1667 }
1668
1669 static struct class *ipath_class;
1670
1671 static int init_cdev(int minor, char *name, struct file_operations *fops,
1672                      struct cdev **cdevp, struct class_device **class_devp)
1673 {
1674         const dev_t dev = MKDEV(IPATH_MAJOR, minor);
1675         struct cdev *cdev = NULL;
1676         struct class_device *class_dev = NULL;
1677         int ret;
1678
1679         cdev = cdev_alloc();
1680         if (!cdev) {
1681                 printk(KERN_ERR IPATH_DRV_NAME
1682                        ": Could not allocate cdev for minor %d, %s\n",
1683                        minor, name);
1684                 ret = -ENOMEM;
1685                 goto done;
1686         }
1687
1688         cdev->owner = THIS_MODULE;
1689         cdev->ops = fops;
1690         kobject_set_name(&cdev->kobj, name);
1691
1692         ret = cdev_add(cdev, dev, 1);
1693         if (ret < 0) {
1694                 printk(KERN_ERR IPATH_DRV_NAME
1695                        ": Could not add cdev for minor %d, %s (err %d)\n",
1696                        minor, name, -ret);
1697                 goto err_cdev;
1698         }
1699
1700         class_dev = class_device_create(ipath_class, NULL, dev, NULL, name);
1701
1702         if (IS_ERR(class_dev)) {
1703                 ret = PTR_ERR(class_dev);
1704                 printk(KERN_ERR IPATH_DRV_NAME ": Could not create "
1705                        "class_dev for minor %d, %s (err %d)\n",
1706                        minor, name, -ret);
1707                 goto err_cdev;
1708         }
1709
1710         goto done;
1711
1712 err_cdev:
1713         cdev_del(cdev);
1714         cdev = NULL;
1715
1716 done:
1717         if (ret >= 0) {
1718                 *cdevp = cdev;
1719                 *class_devp = class_dev;
1720         } else {
1721                 *cdevp = NULL;
1722                 *class_devp = NULL;
1723         }
1724
1725         return ret;
1726 }
1727
1728 int ipath_cdev_init(int minor, char *name, struct file_operations *fops,
1729                     struct cdev **cdevp, struct class_device **class_devp)
1730 {
1731         return init_cdev(minor, name, fops, cdevp, class_devp);
1732 }
1733
1734 static void cleanup_cdev(struct cdev **cdevp,
1735                          struct class_device **class_devp)
1736 {
1737         struct class_device *class_dev = *class_devp;
1738
1739         if (class_dev) {
1740                 class_device_unregister(class_dev);
1741                 *class_devp = NULL;
1742         }
1743
1744         if (*cdevp) {
1745                 cdev_del(*cdevp);
1746                 *cdevp = NULL;
1747         }
1748 }
1749
1750 void ipath_cdev_cleanup(struct cdev **cdevp,
1751                         struct class_device **class_devp)
1752 {
1753         cleanup_cdev(cdevp, class_devp);
1754 }
1755
1756 static struct cdev *wildcard_cdev;
1757 static struct class_device *wildcard_class_dev;
1758
1759 static const dev_t dev = MKDEV(IPATH_MAJOR, 0);
1760
1761 static int user_init(void)
1762 {
1763         int ret;
1764
1765         ret = register_chrdev_region(dev, IPATH_NMINORS, IPATH_DRV_NAME);
1766         if (ret < 0) {
1767                 printk(KERN_ERR IPATH_DRV_NAME ": Could not register "
1768                        "chrdev region (err %d)\n", -ret);
1769                 goto done;
1770         }
1771
1772         ipath_class = class_create(THIS_MODULE, IPATH_DRV_NAME);
1773
1774         if (IS_ERR(ipath_class)) {
1775                 ret = PTR_ERR(ipath_class);
1776                 printk(KERN_ERR IPATH_DRV_NAME ": Could not create "
1777                        "device class (err %d)\n", -ret);
1778                 goto bail;
1779         }
1780
1781         goto done;
1782 bail:
1783         unregister_chrdev_region(dev, IPATH_NMINORS);
1784 done:
1785         return ret;
1786 }
1787
1788 static void user_cleanup(void)
1789 {
1790         if (ipath_class) {
1791                 class_destroy(ipath_class);
1792                 ipath_class = NULL;
1793         }
1794
1795         unregister_chrdev_region(dev, IPATH_NMINORS);
1796 }
1797
1798 static atomic_t user_count = ATOMIC_INIT(0);
1799 static atomic_t user_setup = ATOMIC_INIT(0);
1800
1801 int ipath_user_add(struct ipath_devdata *dd)
1802 {
1803         char name[10];
1804         int ret;
1805
1806         if (atomic_inc_return(&user_count) == 1) {
1807                 ret = user_init();
1808                 if (ret < 0) {
1809                         ipath_dev_err(dd, "Unable to set up user support: "
1810                                       "error %d\n", -ret);
1811                         goto bail;
1812                 }
1813                 ret = init_cdev(0, "ipath", &ipath_file_ops, &wildcard_cdev,
1814                                 &wildcard_class_dev);
1815                 if (ret < 0) {
1816                         ipath_dev_err(dd, "Could not create wildcard "
1817                                       "minor: error %d\n", -ret);
1818                         goto bail_sma;
1819                 }
1820
1821                 atomic_set(&user_setup, 1);
1822         }
1823
1824         snprintf(name, sizeof(name), "ipath%d", dd->ipath_unit);
1825
1826         ret = init_cdev(dd->ipath_unit + 1, name, &ipath_file_ops,
1827                         &dd->user_cdev, &dd->user_class_dev);
1828         if (ret < 0)
1829                 ipath_dev_err(dd, "Could not create user minor %d, %s\n",
1830                               dd->ipath_unit + 1, name);
1831
1832         goto bail;
1833
1834 bail_sma:
1835         user_cleanup();
1836 bail:
1837         return ret;
1838 }
1839
1840 void ipath_user_remove(struct ipath_devdata *dd)
1841 {
1842         cleanup_cdev(&dd->user_cdev, &dd->user_class_dev);
1843
1844         if (atomic_dec_return(&user_count) == 0) {
1845                 if (atomic_read(&user_setup) == 0)
1846                         goto bail;
1847
1848                 cleanup_cdev(&wildcard_cdev, &wildcard_class_dev);
1849                 user_cleanup();
1850
1851                 atomic_set(&user_setup, 0);
1852         }
1853 bail:
1854         return;
1855 }
1856