1/*
2 * Copyright (c) 2004 Topspin Communications.  All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses.  You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 *     Redistribution and use in source and binary forms, with or
11 *     without modification, are permitted provided that the following
12 *     conditions are met:
13 *
14 *      - Redistributions of source code must retain the above
15 *        copyright notice, this list of conditions and the following
16 *        disclaimer.
17 *
18 *      - Redistributions in binary form must reproduce the above
19 *        copyright notice, this list of conditions and the following
20 *        disclaimer in the documentation and/or other materials
21 *        provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33#include <linux/errno.h>
34#include <linux/slab.h>
35#include <linux/bitmap.h>
36
37#include "mthca_dev.h"
38
39/* Trivial bitmap-based allocator */
40u32 mthca_alloc(struct mthca_alloc *alloc)
41{
42	unsigned long flags;
43	u32 obj;
44
45	spin_lock_irqsave(&alloc->lock, flags);
46
47	obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last);
48	if (obj >= alloc->max) {
49		alloc->top = (alloc->top + alloc->max) & alloc->mask;
50		obj = find_first_zero_bit(alloc->table, alloc->max);
51	}
52
53	if (obj < alloc->max) {
54		__set_bit(obj, alloc->table);
55		obj |= alloc->top;
56	} else
57		obj = -1;
58
59	spin_unlock_irqrestore(&alloc->lock, flags);
60
61	return obj;
62}
63
64void mthca_free(struct mthca_alloc *alloc, u32 obj)
65{
66	unsigned long flags;
67
68	obj &= alloc->max - 1;
69
70	spin_lock_irqsave(&alloc->lock, flags);
71
72	__clear_bit(obj, alloc->table);
73	alloc->last = min(alloc->last, obj);
74	alloc->top = (alloc->top + alloc->max) & alloc->mask;
75
76	spin_unlock_irqrestore(&alloc->lock, flags);
77}
78
79int mthca_alloc_init(struct mthca_alloc *alloc, u32 num, u32 mask,
80		     u32 reserved)
81{
82	/* num must be a power of 2 */
83	if (num != 1 << (ffs(num) - 1))
84		return -EINVAL;
85
86	alloc->last = 0;
87	alloc->top  = 0;
88	alloc->max  = num;
89	alloc->mask = mask;
90	spin_lock_init(&alloc->lock);
91	alloc->table = bitmap_zalloc(num, GFP_KERNEL);
92	if (!alloc->table)
93		return -ENOMEM;
94
95	bitmap_set(alloc->table, 0, reserved);
96
97	return 0;
98}
99
100void mthca_alloc_cleanup(struct mthca_alloc *alloc)
101{
102	bitmap_free(alloc->table);
103}
104
105/*
106 * Array of pointers with lazy allocation of leaf pages.  Callers of
107 * _get, _set and _clear methods must use a lock or otherwise
108 * serialize access to the array.
109 */
110
111#define MTHCA_ARRAY_MASK (PAGE_SIZE / sizeof (void *) - 1)
112
113void *mthca_array_get(struct mthca_array *array, int index)
114{
115	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
116
117	if (array->page_list[p].page)
118		return array->page_list[p].page[index & MTHCA_ARRAY_MASK];
119	else
120		return NULL;
121}
122
123int mthca_array_set(struct mthca_array *array, int index, void *value)
124{
125	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
126
127	/* Allocate with GFP_ATOMIC because we'll be called with locks held. */
128	if (!array->page_list[p].page)
129		array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC);
130
131	if (!array->page_list[p].page)
132		return -ENOMEM;
133
134	array->page_list[p].page[index & MTHCA_ARRAY_MASK] = value;
135	++array->page_list[p].used;
136
137	return 0;
138}
139
140void mthca_array_clear(struct mthca_array *array, int index)
141{
142	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
143
144	if (--array->page_list[p].used == 0) {
145		free_page((unsigned long) array->page_list[p].page);
146		array->page_list[p].page = NULL;
147	} else
148		array->page_list[p].page[index & MTHCA_ARRAY_MASK] = NULL;
149
150	if (array->page_list[p].used < 0)
151		pr_debug("Array %p index %d page %d with ref count %d < 0\n",
152			 array, index, p, array->page_list[p].used);
153}
154
155int mthca_array_init(struct mthca_array *array, int nent)
156{
157	int npage = (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE;
158	int i;
159
160	array->page_list = kmalloc_array(npage, sizeof(*array->page_list),
161					 GFP_KERNEL);
162	if (!array->page_list)
163		return -ENOMEM;
164
165	for (i = 0; i < npage; ++i) {
166		array->page_list[i].page = NULL;
167		array->page_list[i].used = 0;
168	}
169
170	return 0;
171}
172
173void mthca_array_cleanup(struct mthca_array *array, int nent)
174{
175	int i;
176
177	for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
178		free_page((unsigned long) array->page_list[i].page);
179
180	kfree(array->page_list);
181}
182
183/*
184 * Handling for queue buffers -- we allocate a bunch of memory and
185 * register it in a memory region at HCA virtual address 0.  If the
186 * requested size is > max_direct, we split the allocation into
187 * multiple pages, so we don't require too much contiguous memory.
188 */
189
190int mthca_buf_alloc(struct mthca_dev *dev, int size, int max_direct,
191		    union mthca_buf *buf, int *is_direct, struct mthca_pd *pd,
192		    int hca_write, struct mthca_mr *mr)
193{
194	int err = -ENOMEM;
195	int npages, shift;
196	u64 *dma_list = NULL;
197	dma_addr_t t;
198	int i;
199
200	if (size <= max_direct) {
201		*is_direct = 1;
202		npages     = 1;
203		shift      = get_order(size) + PAGE_SHIFT;
204
205		buf->direct.buf = dma_alloc_coherent(&dev->pdev->dev,
206						     size, &t, GFP_KERNEL);
207		if (!buf->direct.buf)
208			return -ENOMEM;
209
210		dma_unmap_addr_set(&buf->direct, mapping, t);
211
212		while (t & ((1 << shift) - 1)) {
213			--shift;
214			npages *= 2;
215		}
216
217		dma_list = kmalloc_array(npages, sizeof(*dma_list),
218					 GFP_KERNEL);
219		if (!dma_list)
220			goto err_free;
221
222		for (i = 0; i < npages; ++i)
223			dma_list[i] = t + i * (1 << shift);
224	} else {
225		*is_direct = 0;
226		npages     = (size + PAGE_SIZE - 1) / PAGE_SIZE;
227		shift      = PAGE_SHIFT;
228
229		dma_list = kmalloc_array(npages, sizeof(*dma_list),
230					 GFP_KERNEL);
231		if (!dma_list)
232			return -ENOMEM;
233
234		buf->page_list = kmalloc_array(npages,
235					       sizeof(*buf->page_list),
236					       GFP_KERNEL);
237		if (!buf->page_list)
238			goto err_out;
239
240		for (i = 0; i < npages; ++i)
241			buf->page_list[i].buf = NULL;
242
243		for (i = 0; i < npages; ++i) {
244			buf->page_list[i].buf =
245				dma_alloc_coherent(&dev->pdev->dev, PAGE_SIZE,
246						   &t, GFP_KERNEL);
247			if (!buf->page_list[i].buf)
248				goto err_free;
249
250			dma_list[i] = t;
251			dma_unmap_addr_set(&buf->page_list[i], mapping, t);
252
253			clear_page(buf->page_list[i].buf);
254		}
255	}
256
257	err = mthca_mr_alloc_phys(dev, pd->pd_num,
258				  dma_list, shift, npages,
259				  0, size,
260				  MTHCA_MPT_FLAG_LOCAL_READ |
261				  (hca_write ? MTHCA_MPT_FLAG_LOCAL_WRITE : 0),
262				  mr);
263	if (err)
264		goto err_free;
265
266	kfree(dma_list);
267
268	return 0;
269
270err_free:
271	mthca_buf_free(dev, size, buf, *is_direct, NULL);
272
273err_out:
274	kfree(dma_list);
275
276	return err;
277}
278
279void mthca_buf_free(struct mthca_dev *dev, int size, union mthca_buf *buf,
280		    int is_direct, struct mthca_mr *mr)
281{
282	int i;
283
284	if (mr)
285		mthca_free_mr(dev, mr);
286
287	if (is_direct)
288		dma_free_coherent(&dev->pdev->dev, size, buf->direct.buf,
289				  dma_unmap_addr(&buf->direct, mapping));
290	else {
291		for (i = 0; i < (size + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
292			dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
293					  buf->page_list[i].buf,
294					  dma_unmap_addr(&buf->page_list[i],
295							 mapping));
296		kfree(buf->page_list);
297	}
298}
299