alloc.c

  1/*
  2 * Copyright (c) 2006, 2007 Cisco Systems, Inc.  All rights reserved.
  3 * Copyright (c) 2007, 2008 Mellanox Technologies. 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/errno.h>
 35#include <linux/slab.h>
 36#include <linux/mm.h>
 37#include <linux/export.h>
 38#include <linux/bitmap.h>
 39#include <linux/dma-mapping.h>
 40#include <linux/vmalloc.h>
 41
 42#include "mlx4.h"
 43
 44u32 mlx4_bitmap_alloc(struct mlx4_bitmap *bitmap)
 45{
 46	u32 obj;
 47
 48	spin_lock(&bitmap->lock);
 49
 50	obj = find_next_zero_bit(bitmap->table, bitmap->max, bitmap->last);
 51	if (obj >= bitmap->max) {
 52		bitmap->top = (bitmap->top + bitmap->max + bitmap->reserved_top)
 53				& bitmap->mask;
 54		obj = find_first_zero_bit(bitmap->table, bitmap->max);
 55	}
 56
 57	if (obj < bitmap->max) {
 58		set_bit(obj, bitmap->table);
 59		bitmap->last = (obj + 1);
 60		if (bitmap->last == bitmap->max)
 61			bitmap->last = 0;
 62		obj |= bitmap->top;
 63	} else
 64		obj = -1;
 65
 66	if (obj != -1)
 67		--bitmap->avail;
 68
 69	spin_unlock(&bitmap->lock);
 70
 71	return obj;
 72}
 73
 74void mlx4_bitmap_free(struct mlx4_bitmap *bitmap, u32 obj, int use_rr)
 75{
 76	mlx4_bitmap_free_range(bitmap, obj, 1, use_rr);
 77}
 78
 79static unsigned long find_aligned_range(unsigned long *bitmap,
 80					u32 start, u32 nbits,
 81					int len, int align, u32 skip_mask)
 82{
 83	unsigned long end, i;
 84
 85again:
 86	start = ALIGN(start, align);
 87
 88	while ((start < nbits) && (test_bit(start, bitmap) ||
 89				   (start & skip_mask)))
 90		start += align;
 91
 92	if (start >= nbits)
 93		return -1;
 94
 95	end = start+len;
 96	if (end > nbits)
 97		return -1;
 98
 99	for (i = start + 1; i < end; i++) {
100		if (test_bit(i, bitmap) || ((u32)i & skip_mask)) {
101			start = i + 1;
102			goto again;
103		}
104	}
105
106	return start;
107}
108
109u32 mlx4_bitmap_alloc_range(struct mlx4_bitmap *bitmap, int cnt,
110			    int align, u32 skip_mask)
111{
112	u32 obj;
113
114	if (likely(cnt == 1 && align == 1 && !skip_mask))
115		return mlx4_bitmap_alloc(bitmap);
116
117	spin_lock(&bitmap->lock);
118
119	obj = find_aligned_range(bitmap->table, bitmap->last,
120				 bitmap->max, cnt, align, skip_mask);
121	if (obj >= bitmap->max) {
122		bitmap->top = (bitmap->top + bitmap->max + bitmap->reserved_top)
123				& bitmap->mask;
124		obj = find_aligned_range(bitmap->table, 0, bitmap->max,
125					 cnt, align, skip_mask);
126	}
127
128	if (obj < bitmap->max) {
129		bitmap_set(bitmap->table, obj, cnt);
130		if (obj == bitmap->last) {
131			bitmap->last = (obj + cnt);
132			if (bitmap->last >= bitmap->max)
133				bitmap->last = 0;
134		}
135		obj |= bitmap->top;
136	} else
137		obj = -1;
138
139	if (obj != -1)
140		bitmap->avail -= cnt;
141
142	spin_unlock(&bitmap->lock);
143
144	return obj;
145}
146
147u32 mlx4_bitmap_avail(struct mlx4_bitmap *bitmap)
148{
149	return bitmap->avail;
150}
151
152static u32 mlx4_bitmap_masked_value(struct mlx4_bitmap *bitmap, u32 obj)
153{
154	return obj & (bitmap->max + bitmap->reserved_top - 1);
155}
156
157void mlx4_bitmap_free_range(struct mlx4_bitmap *bitmap, u32 obj, int cnt,
158			    int use_rr)
159{
160	obj &= bitmap->max + bitmap->reserved_top - 1;
161
162	spin_lock(&bitmap->lock);
163	if (!use_rr) {
164		bitmap->last = min(bitmap->last, obj);
165		bitmap->top = (bitmap->top + bitmap->max + bitmap->reserved_top)
166				& bitmap->mask;
167	}
168	bitmap_clear(bitmap->table, obj, cnt);
169	bitmap->avail += cnt;
170	spin_unlock(&bitmap->lock);
171}
172
173int mlx4_bitmap_init(struct mlx4_bitmap *bitmap, u32 num, u32 mask,
174		     u32 reserved_bot, u32 reserved_top)
175{
176	/* num must be a power of 2 */
177	if (num != roundup_pow_of_two(num))
178		return -EINVAL;
179
180	bitmap->last = 0;
181	bitmap->top  = 0;
182	bitmap->max  = num - reserved_top;
183	bitmap->mask = mask;
184	bitmap->reserved_top = reserved_top;
185	bitmap->avail = num - reserved_top - reserved_bot;
186	bitmap->effective_len = bitmap->avail;
187	spin_lock_init(&bitmap->lock);
188	bitmap->table = bitmap_zalloc(bitmap->max, GFP_KERNEL);
189	if (!bitmap->table)
190		return -ENOMEM;
191
192	bitmap_set(bitmap->table, 0, reserved_bot);
193
194	return 0;
195}
196
197void mlx4_bitmap_cleanup(struct mlx4_bitmap *bitmap)
198{
199	bitmap_free(bitmap->table);
200}
201
202struct mlx4_zone_allocator {
203	struct list_head		entries;
204	struct list_head		prios;
205	u32				last_uid;
206	u32				mask;
207	/* protect the zone_allocator from concurrent accesses */
208	spinlock_t			lock;
209	enum mlx4_zone_alloc_flags	flags;
210};
211
212struct mlx4_zone_entry {
213	struct list_head		list;
214	struct list_head		prio_list;
215	u32				uid;
216	struct mlx4_zone_allocator	*allocator;
217	struct mlx4_bitmap		*bitmap;
218	int				use_rr;
219	int				priority;
220	int				offset;
221	enum mlx4_zone_flags		flags;
222};
223
224struct mlx4_zone_allocator *mlx4_zone_allocator_create(enum mlx4_zone_alloc_flags flags)
225{
226	struct mlx4_zone_allocator *zones = kmalloc(sizeof(*zones), GFP_KERNEL);
227
228	if (NULL == zones)
229		return NULL;
230
231	INIT_LIST_HEAD(&zones->entries);
232	INIT_LIST_HEAD(&zones->prios);
233	spin_lock_init(&zones->lock);
234	zones->last_uid = 0;
235	zones->mask = 0;
236	zones->flags = flags;
237
238	return zones;
239}
240
241int mlx4_zone_add_one(struct mlx4_zone_allocator *zone_alloc,
242		      struct mlx4_bitmap *bitmap,
243		      u32 flags,
244		      int priority,
245		      int offset,
246		      u32 *puid)
247{
248	u32 mask = mlx4_bitmap_masked_value(bitmap, (u32)-1);
249	struct mlx4_zone_entry *it;
250	struct mlx4_zone_entry *zone = kmalloc(sizeof(*zone), GFP_KERNEL);
251
252	if (NULL == zone)
253		return -ENOMEM;
254
255	zone->flags = flags;
256	zone->bitmap = bitmap;
257	zone->use_rr = (flags & MLX4_ZONE_USE_RR) ? MLX4_USE_RR : 0;
258	zone->priority = priority;
259	zone->offset = offset;
260
261	spin_lock(&zone_alloc->lock);
262
263	zone->uid = zone_alloc->last_uid++;
264	zone->allocator = zone_alloc;
265
266	if (zone_alloc->mask < mask)
267		zone_alloc->mask = mask;
268
269	list_for_each_entry(it, &zone_alloc->prios, prio_list)
270		if (it->priority >= priority)
271			break;
272
273	if (&it->prio_list == &zone_alloc->prios || it->priority > priority)
274		list_add_tail(&zone->prio_list, &it->prio_list);
275	list_add_tail(&zone->list, &it->list);
276
277	spin_unlock(&zone_alloc->lock);
278
279	*puid = zone->uid;
280
281	return 0;
282}
283
284/* Should be called under a lock */
285static void __mlx4_zone_remove_one_entry(struct mlx4_zone_entry *entry)
286{
287	struct mlx4_zone_allocator *zone_alloc = entry->allocator;
288
289	if (!list_empty(&entry->prio_list)) {
290		/* Check if we need to add an alternative node to the prio list */
291		if (!list_is_last(&entry->list, &zone_alloc->entries)) {
292			struct mlx4_zone_entry *next = list_first_entry(&entry->list,
293									typeof(*next),
294									list);
295
296			if (next->priority == entry->priority)
297				list_add_tail(&next->prio_list, &entry->prio_list);
298		}
299
300		list_del(&entry->prio_list);
301	}
302
303	list_del(&entry->list);
304
305	if (zone_alloc->flags & MLX4_ZONE_ALLOC_FLAGS_NO_OVERLAP) {
306		u32 mask = 0;
307		struct mlx4_zone_entry *it;
308
309		list_for_each_entry(it, &zone_alloc->prios, prio_list) {
310			u32 cur_mask = mlx4_bitmap_masked_value(it->bitmap, (u32)-1);
311
312			if (mask < cur_mask)
313				mask = cur_mask;
314		}
315		zone_alloc->mask = mask;
316	}
317}
318
319void mlx4_zone_allocator_destroy(struct mlx4_zone_allocator *zone_alloc)
320{
321	struct mlx4_zone_entry *zone, *tmp;
322
323	spin_lock(&zone_alloc->lock);
324
325	list_for_each_entry_safe(zone, tmp, &zone_alloc->entries, list) {
326		list_del(&zone->list);
327		list_del(&zone->prio_list);
328		kfree(zone);
329	}
330
331	spin_unlock(&zone_alloc->lock);
332	kfree(zone_alloc);
333}
334
335/* Should be called under a lock */
336static u32 __mlx4_alloc_from_zone(struct mlx4_zone_entry *zone, int count,
337				  int align, u32 skip_mask, u32 *puid)
338{
339	u32 uid = 0;
340	u32 res;
341	struct mlx4_zone_allocator *zone_alloc = zone->allocator;
342	struct mlx4_zone_entry *curr_node;
343
344	res = mlx4_bitmap_alloc_range(zone->bitmap, count,
345				      align, skip_mask);
346
347	if (res != (u32)-1) {
348		res += zone->offset;
349		uid = zone->uid;
350		goto out;
351	}
352
353	list_for_each_entry(curr_node, &zone_alloc->prios, prio_list) {
354		if (unlikely(curr_node->priority == zone->priority))
355			break;
356	}
357
358	if (zone->flags & MLX4_ZONE_ALLOW_ALLOC_FROM_LOWER_PRIO) {
359		struct mlx4_zone_entry *it = curr_node;
360
361		list_for_each_entry_continue_reverse(it, &zone_alloc->entries, list) {
362			res = mlx4_bitmap_alloc_range(it->bitmap, count,
363						      align, skip_mask);
364			if (res != (u32)-1) {
365				res += it->offset;
366				uid = it->uid;
367				goto out;
368			}
369		}
370	}
371
372	if (zone->flags & MLX4_ZONE_ALLOW_ALLOC_FROM_EQ_PRIO) {
373		struct mlx4_zone_entry *it = curr_node;
374
375		list_for_each_entry_from(it, &zone_alloc->entries, list) {
376			if (unlikely(it == zone))
377				continue;
378
379			if (unlikely(it->priority != curr_node->priority))
380				break;
381
382			res = mlx4_bitmap_alloc_range(it->bitmap, count,
383						      align, skip_mask);
384			if (res != (u32)-1) {
385				res += it->offset;
386				uid = it->uid;
387				goto out;
388			}
389		}
390	}
391
392	if (zone->flags & MLX4_ZONE_FALLBACK_TO_HIGHER_PRIO) {
393		if (list_is_last(&curr_node->prio_list, &zone_alloc->prios))
394			goto out;
395
396		curr_node = list_first_entry(&curr_node->prio_list,
397					     typeof(*curr_node),
398					     prio_list);
399
400		list_for_each_entry_from(curr_node, &zone_alloc->entries, list) {
401			res = mlx4_bitmap_alloc_range(curr_node->bitmap, count,
402						      align, skip_mask);
403			if (res != (u32)-1) {
404				res += curr_node->offset;
405				uid = curr_node->uid;
406				goto out;
407			}
408		}
409	}
410
411out:
412	if (NULL != puid && res != (u32)-1)
413		*puid = uid;
414	return res;
415}
416
417/* Should be called under a lock */
418static void __mlx4_free_from_zone(struct mlx4_zone_entry *zone, u32 obj,
419				  u32 count)
420{
421	mlx4_bitmap_free_range(zone->bitmap, obj - zone->offset, count, zone->use_rr);
422}
423
424/* Should be called under a lock */
425static struct mlx4_zone_entry *__mlx4_find_zone_by_uid(
426		struct mlx4_zone_allocator *zones, u32 uid)
427{
428	struct mlx4_zone_entry *zone;
429
430	list_for_each_entry(zone, &zones->entries, list) {
431		if (zone->uid == uid)
432			return zone;
433	}
434
435	return NULL;
436}
437
438struct mlx4_bitmap *mlx4_zone_get_bitmap(struct mlx4_zone_allocator *zones, u32 uid)
439{
440	struct mlx4_zone_entry *zone;
441	struct mlx4_bitmap *bitmap;
442
443	spin_lock(&zones->lock);
444
445	zone = __mlx4_find_zone_by_uid(zones, uid);
446
447	bitmap = zone == NULL ? NULL : zone->bitmap;
448
449	spin_unlock(&zones->lock);
450
451	return bitmap;
452}
453
454int mlx4_zone_remove_one(struct mlx4_zone_allocator *zones, u32 uid)
455{
456	struct mlx4_zone_entry *zone;
457	int res = 0;
458
459	spin_lock(&zones->lock);
460
461	zone = __mlx4_find_zone_by_uid(zones, uid);
462
463	if (NULL == zone) {
464		res = -1;
465		goto out;
466	}
467
468	__mlx4_zone_remove_one_entry(zone);
469
470out:
471	spin_unlock(&zones->lock);
472	kfree(zone);
473
474	return res;
475}
476
477/* Should be called under a lock */
478static struct mlx4_zone_entry *__mlx4_find_zone_by_uid_unique(
479		struct mlx4_zone_allocator *zones, u32 obj)
480{
481	struct mlx4_zone_entry *zone, *zone_candidate = NULL;
482	u32 dist = (u32)-1;
483
484	/* Search for the smallest zone that this obj could be
485	 * allocated from. This is done in order to handle
486	 * situations when small bitmaps are allocated from bigger
487	 * bitmaps (and the allocated space is marked as reserved in
488	 * the bigger bitmap.
489	 */
490	list_for_each_entry(zone, &zones->entries, list) {
491		if (obj >= zone->offset) {
492			u32 mobj = (obj - zone->offset) & zones->mask;
493
494			if (mobj < zone->bitmap->max) {
495				u32 curr_dist = zone->bitmap->effective_len;
496
497				if (curr_dist < dist) {
498					dist = curr_dist;
499					zone_candidate = zone;
500				}
501			}
502		}
503	}
504
505	return zone_candidate;
506}
507
508u32 mlx4_zone_alloc_entries(struct mlx4_zone_allocator *zones, u32 uid, int count,
509			    int align, u32 skip_mask, u32 *puid)
510{
511	struct mlx4_zone_entry *zone;
512	int res = -1;
513
514	spin_lock(&zones->lock);
515
516	zone = __mlx4_find_zone_by_uid(zones, uid);
517
518	if (NULL == zone)
519		goto out;
520
521	res = __mlx4_alloc_from_zone(zone, count, align, skip_mask, puid);
522
523out:
524	spin_unlock(&zones->lock);
525
526	return res;
527}
528
529u32 mlx4_zone_free_entries_unique(struct mlx4_zone_allocator *zones, u32 obj, u32 count)
530{
531	struct mlx4_zone_entry *zone;
532	int res;
533
534	if (!(zones->flags & MLX4_ZONE_ALLOC_FLAGS_NO_OVERLAP))
535		return -EFAULT;
536
537	spin_lock(&zones->lock);
538
539	zone = __mlx4_find_zone_by_uid_unique(zones, obj);
540
541	if (NULL == zone) {
542		res = -1;
543		goto out;
544	}
545
546	__mlx4_free_from_zone(zone, obj, count);
547	res = 0;
548
549out:
550	spin_unlock(&zones->lock);
551
552	return res;
553}
554
555static int mlx4_buf_direct_alloc(struct mlx4_dev *dev, int size,
556				 struct mlx4_buf *buf)
557{
558	dma_addr_t t;
559
560	buf->nbufs        = 1;
561	buf->npages       = 1;
562	buf->page_shift   = get_order(size) + PAGE_SHIFT;
563	buf->direct.buf   =
564		dma_alloc_coherent(&dev->persist->pdev->dev, size, &t,
565				   GFP_KERNEL);
566	if (!buf->direct.buf)
567		return -ENOMEM;
568
569	buf->direct.map = t;
570
571	while (t & ((1 << buf->page_shift) - 1)) {
572		--buf->page_shift;
573		buf->npages *= 2;
574	}
575
576	return 0;
577}
578
579/* Handling for queue buffers -- we allocate a bunch of memory and
580 * register it in a memory region at HCA virtual address 0. If the
581 *  requested size is > max_direct, we split the allocation into
582 *  multiple pages, so we don't require too much contiguous memory.
583 */
584int mlx4_buf_alloc(struct mlx4_dev *dev, int size, int max_direct,
585		   struct mlx4_buf *buf)
586{
587	if (size <= max_direct) {
588		return mlx4_buf_direct_alloc(dev, size, buf);
589	} else {
590		dma_addr_t t;
591		int i;
592
593		buf->direct.buf = NULL;
594		buf->nbufs      = DIV_ROUND_UP(size, PAGE_SIZE);
595		buf->npages	= buf->nbufs;
596		buf->page_shift  = PAGE_SHIFT;
597		buf->page_list   = kcalloc(buf->nbufs, sizeof(*buf->page_list),
598					   GFP_KERNEL);
599		if (!buf->page_list)
600			return -ENOMEM;
601
602		for (i = 0; i < buf->nbufs; ++i) {
603			buf->page_list[i].buf =
604				dma_alloc_coherent(&dev->persist->pdev->dev,
605						   PAGE_SIZE, &t, GFP_KERNEL);
606			if (!buf->page_list[i].buf)
607				goto err_free;
608
609			buf->page_list[i].map = t;
610		}
611	}
612
613	return 0;
614
615err_free:
616	mlx4_buf_free(dev, size, buf);
617
618	return -ENOMEM;
619}
620EXPORT_SYMBOL_GPL(mlx4_buf_alloc);
621
622void mlx4_buf_free(struct mlx4_dev *dev, int size, struct mlx4_buf *buf)
623{
624	if (buf->nbufs == 1) {
625		dma_free_coherent(&dev->persist->pdev->dev, size,
626				  buf->direct.buf, buf->direct.map);
627	} else {
628		int i;
629
630		for (i = 0; i < buf->nbufs; ++i)
631			if (buf->page_list[i].buf)
632				dma_free_coherent(&dev->persist->pdev->dev,
633						  PAGE_SIZE,
634						  buf->page_list[i].buf,
635						  buf->page_list[i].map);
636		kfree(buf->page_list);
637	}
638}
639EXPORT_SYMBOL_GPL(mlx4_buf_free);
640
641static struct mlx4_db_pgdir *mlx4_alloc_db_pgdir(struct device *dma_device)
642{
643	struct mlx4_db_pgdir *pgdir;
644
645	pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL);
646	if (!pgdir)
647		return NULL;
648
649	bitmap_fill(pgdir->order1, MLX4_DB_PER_PAGE / 2);
650	pgdir->bits[0] = pgdir->order0;
651	pgdir->bits[1] = pgdir->order1;
652	pgdir->db_page = dma_alloc_coherent(dma_device, PAGE_SIZE,
653					    &pgdir->db_dma, GFP_KERNEL);
654	if (!pgdir->db_page) {
655		kfree(pgdir);
656		return NULL;
657	}
658
659	return pgdir;
660}
661
662static int mlx4_alloc_db_from_pgdir(struct mlx4_db_pgdir *pgdir,
663				    struct mlx4_db *db, unsigned int order)
664{
665	unsigned int o;
666	int i;
667
668	for (o = order; o <= 1; ++o) {
669		i = find_first_bit(pgdir->bits[o], MLX4_DB_PER_PAGE >> o);
670		if (i < MLX4_DB_PER_PAGE >> o)
671			goto found;
672	}
673
674	return -ENOMEM;
675
676found:
677	clear_bit(i, pgdir->bits[o]);
678
679	i <<= o;
680
681	if (o > order)
682		set_bit(i ^ 1, pgdir->bits[order]);
683
684	db->u.pgdir = pgdir;
685	db->index   = i;
686	db->db      = pgdir->db_page + db->index;
687	db->dma     = pgdir->db_dma  + db->index * 4;
688	db->order   = order;
689
690	return 0;
691}
692
693int mlx4_db_alloc(struct mlx4_dev *dev, struct mlx4_db *db, unsigned int order)
694{
695	struct mlx4_priv *priv = mlx4_priv(dev);
696	struct mlx4_db_pgdir *pgdir;
697	int ret = 0;
698
699	mutex_lock(&priv->pgdir_mutex);
700
701	list_for_each_entry(pgdir, &priv->pgdir_list, list)
702		if (!mlx4_alloc_db_from_pgdir(pgdir, db, order))
703			goto out;
704
705	pgdir = mlx4_alloc_db_pgdir(&dev->persist->pdev->dev);
706	if (!pgdir) {
707		ret = -ENOMEM;
708		goto out;
709	}
710
711	list_add(&pgdir->list, &priv->pgdir_list);
712
713	/* This should never fail -- we just allocated an empty page: */
714	WARN_ON(mlx4_alloc_db_from_pgdir(pgdir, db, order));
715
716out:
717	mutex_unlock(&priv->pgdir_mutex);
718
719	return ret;
720}
721EXPORT_SYMBOL_GPL(mlx4_db_alloc);
722
723void mlx4_db_free(struct mlx4_dev *dev, struct mlx4_db *db)
724{
725	struct mlx4_priv *priv = mlx4_priv(dev);
726	int o;
727	int i;
728
729	mutex_lock(&priv->pgdir_mutex);
730
731	o = db->order;
732	i = db->index;
733
734	if (db->order == 0 && test_bit(i ^ 1, db->u.pgdir->order0)) {
735		clear_bit(i ^ 1, db->u.pgdir->order0);
736		++o;
737	}
738	i >>= o;
739	set_bit(i, db->u.pgdir->bits[o]);
740
741	if (bitmap_full(db->u.pgdir->order1, MLX4_DB_PER_PAGE / 2)) {
742		dma_free_coherent(&dev->persist->pdev->dev, PAGE_SIZE,
743				  db->u.pgdir->db_page, db->u.pgdir->db_dma);
744		list_del(&db->u.pgdir->list);
745		kfree(db->u.pgdir);
746	}
747
748	mutex_unlock(&priv->pgdir_mutex);
749}
750EXPORT_SYMBOL_GPL(mlx4_db_free);
751
752int mlx4_alloc_hwq_res(struct mlx4_dev *dev, struct mlx4_hwq_resources *wqres,
753		       int size)
754{
755	int err;
756
757	err = mlx4_db_alloc(dev, &wqres->db, 1);
758	if (err)
759		return err;
760
761	*wqres->db.db = 0;
762
763	err = mlx4_buf_direct_alloc(dev, size, &wqres->buf);
764	if (err)
765		goto err_db;
766
767	err = mlx4_mtt_init(dev, wqres->buf.npages, wqres->buf.page_shift,
768			    &wqres->mtt);
769	if (err)
770		goto err_buf;
771
772	err = mlx4_buf_write_mtt(dev, &wqres->mtt, &wqres->buf);
773	if (err)
774		goto err_mtt;
775
776	return 0;
777
778err_mtt:
779	mlx4_mtt_cleanup(dev, &wqres->mtt);
780err_buf:
781	mlx4_buf_free(dev, size, &wqres->buf);
782err_db:
783	mlx4_db_free(dev, &wqres->db);
784
785	return err;
786}
787EXPORT_SYMBOL_GPL(mlx4_alloc_hwq_res);
788
789void mlx4_free_hwq_res(struct mlx4_dev *dev, struct mlx4_hwq_resources *wqres,
790		       int size)
791{
792	mlx4_mtt_cleanup(dev, &wqres->mtt);
793	mlx4_buf_free(dev, size, &wqres->buf);
794	mlx4_db_free(dev, &wqres->db);
795}
796EXPORT_SYMBOL_GPL(mlx4_free_hwq_res);