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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6/drivers/infiniband/hw/mthca/
1/*
2 * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
3 * Copyright (c) 2005 Cisco Systems.  All rights reserved.
4 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
5 *
6 * This software is available to you under a choice of one of two
7 * licenses.  You may choose to be licensed under the terms of the GNU
8 * General Public License (GPL) Version 2, available from the file
9 * COPYING in the main directory of this source tree, or the
10 * OpenIB.org BSD license below:
11 *
12 *     Redistribution and use in source and binary forms, with or
13 *     without modification, are permitted provided that the following
14 *     conditions are met:
15 *
16 *      - Redistributions of source code must retain the above
17 *        copyright notice, this list of conditions and the following
18 *        disclaimer.
19 *
20 *      - Redistributions in binary form must reproduce the above
21 *        copyright notice, this list of conditions and the following
22 *        disclaimer in the documentation and/or other materials
23 *        provided with the distribution.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32 * SOFTWARE.
33 */
34
35#include <linux/mm.h>
36#include <linux/scatterlist.h>
37#include <linux/sched.h>
38#include <linux/slab.h>
39
40#include <asm/page.h>
41
42#include "mthca_memfree.h"
43#include "mthca_dev.h"
44#include "mthca_cmd.h"
45
46/*
47 * We allocate in as big chunks as we can, up to a maximum of 256 KB
48 * per chunk.
49 */
50enum {
51	MTHCA_ICM_ALLOC_SIZE   = 1 << 18,
52	MTHCA_TABLE_CHUNK_SIZE = 1 << 18
53};
54
55struct mthca_user_db_table {
56	struct mutex mutex;
57	struct {
58		u64                uvirt;
59		struct scatterlist mem;
60		int                refcount;
61	}                page[0];
62};
63
64static void mthca_free_icm_pages(struct mthca_dev *dev, struct mthca_icm_chunk *chunk)
65{
66	int i;
67
68	if (chunk->nsg > 0)
69		pci_unmap_sg(dev->pdev, chunk->mem, chunk->npages,
70			     PCI_DMA_BIDIRECTIONAL);
71
72	for (i = 0; i < chunk->npages; ++i)
73		__free_pages(sg_page(&chunk->mem[i]),
74			     get_order(chunk->mem[i].length));
75}
76
77static void mthca_free_icm_coherent(struct mthca_dev *dev, struct mthca_icm_chunk *chunk)
78{
79	int i;
80
81	for (i = 0; i < chunk->npages; ++i) {
82		dma_free_coherent(&dev->pdev->dev, chunk->mem[i].length,
83				  lowmem_page_address(sg_page(&chunk->mem[i])),
84				  sg_dma_address(&chunk->mem[i]));
85	}
86}
87
88void mthca_free_icm(struct mthca_dev *dev, struct mthca_icm *icm, int coherent)
89{
90	struct mthca_icm_chunk *chunk, *tmp;
91
92	if (!icm)
93		return;
94
95	list_for_each_entry_safe(chunk, tmp, &icm->chunk_list, list) {
96		if (coherent)
97			mthca_free_icm_coherent(dev, chunk);
98		else
99			mthca_free_icm_pages(dev, chunk);
100
101		kfree(chunk);
102	}
103
104	kfree(icm);
105}
106
107static int mthca_alloc_icm_pages(struct scatterlist *mem, int order, gfp_t gfp_mask)
108{
109	struct page *page;
110
111	/*
112	 * Use __GFP_ZERO because buggy firmware assumes ICM pages are
113	 * cleared, and subtle failures are seen if they aren't.
114	 */
115	page = alloc_pages(gfp_mask | __GFP_ZERO, order);
116	if (!page)
117		return -ENOMEM;
118
119	sg_set_page(mem, page, PAGE_SIZE << order, 0);
120	return 0;
121}
122
123static int mthca_alloc_icm_coherent(struct device *dev, struct scatterlist *mem,
124				    int order, gfp_t gfp_mask)
125{
126	void *buf = dma_alloc_coherent(dev, PAGE_SIZE << order, &sg_dma_address(mem),
127				       gfp_mask);
128	if (!buf)
129		return -ENOMEM;
130
131	sg_set_buf(mem, buf, PAGE_SIZE << order);
132	BUG_ON(mem->offset);
133	sg_dma_len(mem) = PAGE_SIZE << order;
134	return 0;
135}
136
137struct mthca_icm *mthca_alloc_icm(struct mthca_dev *dev, int npages,
138				  gfp_t gfp_mask, int coherent)
139{
140	struct mthca_icm *icm;
141	struct mthca_icm_chunk *chunk = NULL;
142	int cur_order;
143	int ret;
144
145	/* We use sg_set_buf for coherent allocs, which assumes low memory */
146	BUG_ON(coherent && (gfp_mask & __GFP_HIGHMEM));
147
148	icm = kmalloc(sizeof *icm, gfp_mask & ~(__GFP_HIGHMEM | __GFP_NOWARN));
149	if (!icm)
150		return icm;
151
152	icm->refcount = 0;
153	INIT_LIST_HEAD(&icm->chunk_list);
154
155	cur_order = get_order(MTHCA_ICM_ALLOC_SIZE);
156
157	while (npages > 0) {
158		if (!chunk) {
159			chunk = kmalloc(sizeof *chunk,
160					gfp_mask & ~(__GFP_HIGHMEM | __GFP_NOWARN));
161			if (!chunk)
162				goto fail;
163
164			sg_init_table(chunk->mem, MTHCA_ICM_CHUNK_LEN);
165			chunk->npages = 0;
166			chunk->nsg    = 0;
167			list_add_tail(&chunk->list, &icm->chunk_list);
168		}
169
170		while (1 << cur_order > npages)
171			--cur_order;
172
173		if (coherent)
174			ret = mthca_alloc_icm_coherent(&dev->pdev->dev,
175						       &chunk->mem[chunk->npages],
176						       cur_order, gfp_mask);
177		else
178			ret = mthca_alloc_icm_pages(&chunk->mem[chunk->npages],
179						    cur_order, gfp_mask);
180
181		if (!ret) {
182			++chunk->npages;
183
184			if (coherent)
185				++chunk->nsg;
186			else if (chunk->npages == MTHCA_ICM_CHUNK_LEN) {
187				chunk->nsg = pci_map_sg(dev->pdev, chunk->mem,
188							chunk->npages,
189							PCI_DMA_BIDIRECTIONAL);
190
191				if (chunk->nsg <= 0)
192					goto fail;
193			}
194
195			if (chunk->npages == MTHCA_ICM_CHUNK_LEN)
196				chunk = NULL;
197
198			npages -= 1 << cur_order;
199		} else {
200			--cur_order;
201			if (cur_order < 0)
202				goto fail;
203		}
204	}
205
206	if (!coherent && chunk) {
207		chunk->nsg = pci_map_sg(dev->pdev, chunk->mem,
208					chunk->npages,
209					PCI_DMA_BIDIRECTIONAL);
210
211		if (chunk->nsg <= 0)
212			goto fail;
213	}
214
215	return icm;
216
217fail:
218	mthca_free_icm(dev, icm, coherent);
219	return NULL;
220}
221
222int mthca_table_get(struct mthca_dev *dev, struct mthca_icm_table *table, int obj)
223{
224	int i = (obj & (table->num_obj - 1)) * table->obj_size / MTHCA_TABLE_CHUNK_SIZE;
225	int ret = 0;
226	u8 status;
227
228	mutex_lock(&table->mutex);
229
230	if (table->icm[i]) {
231		++table->icm[i]->refcount;
232		goto out;
233	}
234
235	table->icm[i] = mthca_alloc_icm(dev, MTHCA_TABLE_CHUNK_SIZE >> PAGE_SHIFT,
236					(table->lowmem ? GFP_KERNEL : GFP_HIGHUSER) |
237					__GFP_NOWARN, table->coherent);
238	if (!table->icm[i]) {
239		ret = -ENOMEM;
240		goto out;
241	}
242
243	if (mthca_MAP_ICM(dev, table->icm[i], table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
244			  &status) || status) {
245		mthca_free_icm(dev, table->icm[i], table->coherent);
246		table->icm[i] = NULL;
247		ret = -ENOMEM;
248		goto out;
249	}
250
251	++table->icm[i]->refcount;
252
253out:
254	mutex_unlock(&table->mutex);
255	return ret;
256}
257
258void mthca_table_put(struct mthca_dev *dev, struct mthca_icm_table *table, int obj)
259{
260	int i;
261	u8 status;
262
263	if (!mthca_is_memfree(dev))
264		return;
265
266	i = (obj & (table->num_obj - 1)) * table->obj_size / MTHCA_TABLE_CHUNK_SIZE;
267
268	mutex_lock(&table->mutex);
269
270	if (--table->icm[i]->refcount == 0) {
271		mthca_UNMAP_ICM(dev, table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
272				MTHCA_TABLE_CHUNK_SIZE / MTHCA_ICM_PAGE_SIZE,
273				&status);
274		mthca_free_icm(dev, table->icm[i], table->coherent);
275		table->icm[i] = NULL;
276	}
277
278	mutex_unlock(&table->mutex);
279}
280
281void *mthca_table_find(struct mthca_icm_table *table, int obj, dma_addr_t *dma_handle)
282{
283	int idx, offset, dma_offset, i;
284	struct mthca_icm_chunk *chunk;
285	struct mthca_icm *icm;
286	struct page *page = NULL;
287
288	if (!table->lowmem)
289		return NULL;
290
291	mutex_lock(&table->mutex);
292
293	idx = (obj & (table->num_obj - 1)) * table->obj_size;
294	icm = table->icm[idx / MTHCA_TABLE_CHUNK_SIZE];
295	dma_offset = offset = idx % MTHCA_TABLE_CHUNK_SIZE;
296
297	if (!icm)
298		goto out;
299
300	list_for_each_entry(chunk, &icm->chunk_list, list) {
301		for (i = 0; i < chunk->npages; ++i) {
302			if (dma_handle && dma_offset >= 0) {
303				if (sg_dma_len(&chunk->mem[i]) > dma_offset)
304					*dma_handle = sg_dma_address(&chunk->mem[i]) +
305						dma_offset;
306				dma_offset -= sg_dma_len(&chunk->mem[i]);
307			}
308			/* DMA mapping can merge pages but not split them,
309			 * so if we found the page, dma_handle has already
310			 * been assigned to. */
311			if (chunk->mem[i].length > offset) {
312				page = sg_page(&chunk->mem[i]);
313				goto out;
314			}
315			offset -= chunk->mem[i].length;
316		}
317	}
318
319out:
320	mutex_unlock(&table->mutex);
321	return page ? lowmem_page_address(page) + offset : NULL;
322}
323
324int mthca_table_get_range(struct mthca_dev *dev, struct mthca_icm_table *table,
325			  int start, int end)
326{
327	int inc = MTHCA_TABLE_CHUNK_SIZE / table->obj_size;
328	int i, err;
329
330	for (i = start; i <= end; i += inc) {
331		err = mthca_table_get(dev, table, i);
332		if (err)
333			goto fail;
334	}
335
336	return 0;
337
338fail:
339	while (i > start) {
340		i -= inc;
341		mthca_table_put(dev, table, i);
342	}
343
344	return err;
345}
346
347void mthca_table_put_range(struct mthca_dev *dev, struct mthca_icm_table *table,
348			   int start, int end)
349{
350	int i;
351
352	if (!mthca_is_memfree(dev))
353		return;
354
355	for (i = start; i <= end; i += MTHCA_TABLE_CHUNK_SIZE / table->obj_size)
356		mthca_table_put(dev, table, i);
357}
358
359struct mthca_icm_table *mthca_alloc_icm_table(struct mthca_dev *dev,
360					      u64 virt, int obj_size,
361					      int nobj, int reserved,
362					      int use_lowmem, int use_coherent)
363{
364	struct mthca_icm_table *table;
365	int obj_per_chunk;
366	int num_icm;
367	unsigned chunk_size;
368	int i;
369	u8 status;
370
371	obj_per_chunk = MTHCA_TABLE_CHUNK_SIZE / obj_size;
372	num_icm = DIV_ROUND_UP(nobj, obj_per_chunk);
373
374	table = kmalloc(sizeof *table + num_icm * sizeof *table->icm, GFP_KERNEL);
375	if (!table)
376		return NULL;
377
378	table->virt     = virt;
379	table->num_icm  = num_icm;
380	table->num_obj  = nobj;
381	table->obj_size = obj_size;
382	table->lowmem   = use_lowmem;
383	table->coherent = use_coherent;
384	mutex_init(&table->mutex);
385
386	for (i = 0; i < num_icm; ++i)
387		table->icm[i] = NULL;
388
389	for (i = 0; i * MTHCA_TABLE_CHUNK_SIZE < reserved * obj_size; ++i) {
390		chunk_size = MTHCA_TABLE_CHUNK_SIZE;
391		if ((i + 1) * MTHCA_TABLE_CHUNK_SIZE > nobj * obj_size)
392			chunk_size = nobj * obj_size - i * MTHCA_TABLE_CHUNK_SIZE;
393
394		table->icm[i] = mthca_alloc_icm(dev, chunk_size >> PAGE_SHIFT,
395						(use_lowmem ? GFP_KERNEL : GFP_HIGHUSER) |
396						__GFP_NOWARN, use_coherent);
397		if (!table->icm[i])
398			goto err;
399		if (mthca_MAP_ICM(dev, table->icm[i], virt + i * MTHCA_TABLE_CHUNK_SIZE,
400				  &status) || status) {
401			mthca_free_icm(dev, table->icm[i], table->coherent);
402			table->icm[i] = NULL;
403			goto err;
404		}
405
406		/*
407		 * Add a reference to this ICM chunk so that it never
408		 * gets freed (since it contains reserved firmware objects).
409		 */
410		++table->icm[i]->refcount;
411	}
412
413	return table;
414
415err:
416	for (i = 0; i < num_icm; ++i)
417		if (table->icm[i]) {
418			mthca_UNMAP_ICM(dev, virt + i * MTHCA_TABLE_CHUNK_SIZE,
419					MTHCA_TABLE_CHUNK_SIZE / MTHCA_ICM_PAGE_SIZE,
420					&status);
421			mthca_free_icm(dev, table->icm[i], table->coherent);
422		}
423
424	kfree(table);
425
426	return NULL;
427}
428
429void mthca_free_icm_table(struct mthca_dev *dev, struct mthca_icm_table *table)
430{
431	int i;
432	u8 status;
433
434	for (i = 0; i < table->num_icm; ++i)
435		if (table->icm[i]) {
436			mthca_UNMAP_ICM(dev, table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
437					MTHCA_TABLE_CHUNK_SIZE / MTHCA_ICM_PAGE_SIZE,
438					&status);
439			mthca_free_icm(dev, table->icm[i], table->coherent);
440		}
441
442	kfree(table);
443}
444
445static u64 mthca_uarc_virt(struct mthca_dev *dev, struct mthca_uar *uar, int page)
446{
447	return dev->uar_table.uarc_base +
448		uar->index * dev->uar_table.uarc_size +
449		page * MTHCA_ICM_PAGE_SIZE;
450}
451
452int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
453		      struct mthca_user_db_table *db_tab, int index, u64 uaddr)
454{
455	struct page *pages[1];
456	int ret = 0;
457	u8 status;
458	int i;
459
460	if (!mthca_is_memfree(dev))
461		return 0;
462
463	if (index < 0 || index > dev->uar_table.uarc_size / 8)
464		return -EINVAL;
465
466	mutex_lock(&db_tab->mutex);
467
468	i = index / MTHCA_DB_REC_PER_PAGE;
469
470	if ((db_tab->page[i].refcount >= MTHCA_DB_REC_PER_PAGE)       ||
471	    (db_tab->page[i].uvirt && db_tab->page[i].uvirt != uaddr) ||
472	    (uaddr & 4095)) {
473		ret = -EINVAL;
474		goto out;
475	}
476
477	if (db_tab->page[i].refcount) {
478		++db_tab->page[i].refcount;
479		goto out;
480	}
481
482	ret = get_user_pages(current, current->mm, uaddr & PAGE_MASK, 1, 1, 0,
483			     pages, NULL);
484	if (ret < 0)
485		goto out;
486
487	sg_set_page(&db_tab->page[i].mem, pages[0], MTHCA_ICM_PAGE_SIZE,
488			uaddr & ~PAGE_MASK);
489
490	ret = pci_map_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
491	if (ret < 0) {
492		put_page(pages[0]);
493		goto out;
494	}
495
496	ret = mthca_MAP_ICM_page(dev, sg_dma_address(&db_tab->page[i].mem),
497				 mthca_uarc_virt(dev, uar, i), &status);
498	if (!ret && status)
499		ret = -EINVAL;
500	if (ret) {
501		pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
502		put_page(sg_page(&db_tab->page[i].mem));
503		goto out;
504	}
505
506	db_tab->page[i].uvirt    = uaddr;
507	db_tab->page[i].refcount = 1;
508
509out:
510	mutex_unlock(&db_tab->mutex);
511	return ret;
512}
513
514void mthca_unmap_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
515			 struct mthca_user_db_table *db_tab, int index)
516{
517	if (!mthca_is_memfree(dev))
518		return;
519
520	/*
521	 * To make our bookkeeping simpler, we don't unmap DB
522	 * pages until we clean up the whole db table.
523	 */
524
525	mutex_lock(&db_tab->mutex);
526
527	--db_tab->page[index / MTHCA_DB_REC_PER_PAGE].refcount;
528
529	mutex_unlock(&db_tab->mutex);
530}
531
532struct mthca_user_db_table *mthca_init_user_db_tab(struct mthca_dev *dev)
533{
534	struct mthca_user_db_table *db_tab;
535	int npages;
536	int i;
537
538	if (!mthca_is_memfree(dev))
539		return NULL;
540
541	npages = dev->uar_table.uarc_size / MTHCA_ICM_PAGE_SIZE;
542	db_tab = kmalloc(sizeof *db_tab + npages * sizeof *db_tab->page, GFP_KERNEL);
543	if (!db_tab)
544		return ERR_PTR(-ENOMEM);
545
546	mutex_init(&db_tab->mutex);
547	for (i = 0; i < npages; ++i) {
548		db_tab->page[i].refcount = 0;
549		db_tab->page[i].uvirt    = 0;
550		sg_init_table(&db_tab->page[i].mem, 1);
551	}
552
553	return db_tab;
554}
555
556void mthca_cleanup_user_db_tab(struct mthca_dev *dev, struct mthca_uar *uar,
557			       struct mthca_user_db_table *db_tab)
558{
559	int i;
560	u8 status;
561
562	if (!mthca_is_memfree(dev))
563		return;
564
565	for (i = 0; i < dev->uar_table.uarc_size / MTHCA_ICM_PAGE_SIZE; ++i) {
566		if (db_tab->page[i].uvirt) {
567			mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, uar, i), 1, &status);
568			pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
569			put_page(sg_page(&db_tab->page[i].mem));
570		}
571	}
572
573	kfree(db_tab);
574}
575
576int mthca_alloc_db(struct mthca_dev *dev, enum mthca_db_type type,
577		   u32 qn, __be32 **db)
578{
579	int group;
580	int start, end, dir;
581	int i, j;
582	struct mthca_db_page *page;
583	int ret = 0;
584	u8 status;
585
586	mutex_lock(&dev->db_tab->mutex);
587
588	switch (type) {
589	case MTHCA_DB_TYPE_CQ_ARM:
590	case MTHCA_DB_TYPE_SQ:
591		group = 0;
592		start = 0;
593		end   = dev->db_tab->max_group1;
594		dir   = 1;
595		break;
596
597	case MTHCA_DB_TYPE_CQ_SET_CI:
598	case MTHCA_DB_TYPE_RQ:
599	case MTHCA_DB_TYPE_SRQ:
600		group = 1;
601		start = dev->db_tab->npages - 1;
602		end   = dev->db_tab->min_group2;
603		dir   = -1;
604		break;
605
606	default:
607		ret = -EINVAL;
608		goto out;
609	}
610
611	for (i = start; i != end; i += dir)
612		if (dev->db_tab->page[i].db_rec &&
613		    !bitmap_full(dev->db_tab->page[i].used,
614				 MTHCA_DB_REC_PER_PAGE)) {
615			page = dev->db_tab->page + i;
616			goto found;
617		}
618
619	for (i = start; i != end; i += dir)
620		if (!dev->db_tab->page[i].db_rec) {
621			page = dev->db_tab->page + i;
622			goto alloc;
623		}
624
625	if (dev->db_tab->max_group1 >= dev->db_tab->min_group2 - 1) {
626		ret = -ENOMEM;
627		goto out;
628	}
629
630	if (group == 0)
631		++dev->db_tab->max_group1;
632	else
633		--dev->db_tab->min_group2;
634
635	page = dev->db_tab->page + end;
636
637alloc:
638	page->db_rec = dma_alloc_coherent(&dev->pdev->dev, MTHCA_ICM_PAGE_SIZE,
639					  &page->mapping, GFP_KERNEL);
640	if (!page->db_rec) {
641		ret = -ENOMEM;
642		goto out;
643	}
644	memset(page->db_rec, 0, MTHCA_ICM_PAGE_SIZE);
645
646	ret = mthca_MAP_ICM_page(dev, page->mapping,
647				 mthca_uarc_virt(dev, &dev->driver_uar, i), &status);
648	if (!ret && status)
649		ret = -EINVAL;
650	if (ret) {
651		dma_free_coherent(&dev->pdev->dev, MTHCA_ICM_PAGE_SIZE,
652				  page->db_rec, page->mapping);
653		goto out;
654	}
655
656	bitmap_zero(page->used, MTHCA_DB_REC_PER_PAGE);
657
658found:
659	j = find_first_zero_bit(page->used, MTHCA_DB_REC_PER_PAGE);
660	set_bit(j, page->used);
661
662	if (group == 1)
663		j = MTHCA_DB_REC_PER_PAGE - 1 - j;
664
665	ret = i * MTHCA_DB_REC_PER_PAGE + j;
666
667	page->db_rec[j] = cpu_to_be64((qn << 8) | (type << 5));
668
669	*db = (__be32 *) &page->db_rec[j];
670
671out:
672	mutex_unlock(&dev->db_tab->mutex);
673
674	return ret;
675}
676
677void mthca_free_db(struct mthca_dev *dev, int type, int db_index)
678{
679	int i, j;
680	struct mthca_db_page *page;
681	u8 status;
682
683	i = db_index / MTHCA_DB_REC_PER_PAGE;
684	j = db_index % MTHCA_DB_REC_PER_PAGE;
685
686	page = dev->db_tab->page + i;
687
688	mutex_lock(&dev->db_tab->mutex);
689
690	page->db_rec[j] = 0;
691	if (i >= dev->db_tab->min_group2)
692		j = MTHCA_DB_REC_PER_PAGE - 1 - j;
693	clear_bit(j, page->used);
694
695	if (bitmap_empty(page->used, MTHCA_DB_REC_PER_PAGE) &&
696	    i >= dev->db_tab->max_group1 - 1) {
697		mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, &dev->driver_uar, i), 1, &status);
698
699		dma_free_coherent(&dev->pdev->dev, MTHCA_ICM_PAGE_SIZE,
700				  page->db_rec, page->mapping);
701		page->db_rec = NULL;
702
703		if (i == dev->db_tab->max_group1) {
704			--dev->db_tab->max_group1;
705		}
706		if (i == dev->db_tab->min_group2)
707			++dev->db_tab->min_group2;
708	}
709
710	mutex_unlock(&dev->db_tab->mutex);
711}
712
713int mthca_init_db_tab(struct mthca_dev *dev)
714{
715	int i;
716
717	if (!mthca_is_memfree(dev))
718		return 0;
719
720	dev->db_tab = kmalloc(sizeof *dev->db_tab, GFP_KERNEL);
721	if (!dev->db_tab)
722		return -ENOMEM;
723
724	mutex_init(&dev->db_tab->mutex);
725
726	dev->db_tab->npages     = dev->uar_table.uarc_size / MTHCA_ICM_PAGE_SIZE;
727	dev->db_tab->max_group1 = 0;
728	dev->db_tab->min_group2 = dev->db_tab->npages - 1;
729
730	dev->db_tab->page = kmalloc(dev->db_tab->npages *
731				    sizeof *dev->db_tab->page,
732				    GFP_KERNEL);
733	if (!dev->db_tab->page) {
734		kfree(dev->db_tab);
735		return -ENOMEM;
736	}
737
738	for (i = 0; i < dev->db_tab->npages; ++i)
739		dev->db_tab->page[i].db_rec = NULL;
740
741	return 0;
742}
743
744void mthca_cleanup_db_tab(struct mthca_dev *dev)
745{
746	int i;
747	u8 status;
748
749	if (!mthca_is_memfree(dev))
750		return;
751
752	/*
753	 * Because we don't always free our UARC pages when they
754	 * become empty to make mthca_free_db() simpler we need to
755	 * make a sweep through the doorbell pages and free any
756	 * leftover pages now.
757	 */
758	for (i = 0; i < dev->db_tab->npages; ++i) {
759		if (!dev->db_tab->page[i].db_rec)
760			continue;
761
762		if (!bitmap_empty(dev->db_tab->page[i].used, MTHCA_DB_REC_PER_PAGE))
763			mthca_warn(dev, "Kernel UARC page %d not empty\n", i);
764
765		mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, &dev->driver_uar, i), 1, &status);
766
767		dma_free_coherent(&dev->pdev->dev, MTHCA_ICM_PAGE_SIZE,
768				  dev->db_tab->page[i].db_rec,
769				  dev->db_tab->page[i].mapping);
770	}
771
772	kfree(dev->db_tab->page);
773	kfree(dev->db_tab);
774}
775