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	int i;
83
84	/* num must be a power of 2 */
85	if (num != 1 << (ffs(num) - 1))
86		return -EINVAL;
87
88	alloc->last = 0;
89	alloc->top  = 0;
90	alloc->max  = num;
91	alloc->mask = mask;
92	spin_lock_init(&alloc->lock);
93	alloc->table = kmalloc(BITS_TO_LONGS(num) * sizeof (long),
94			       GFP_KERNEL);
95	if (!alloc->table)
96		return -ENOMEM;
97
98	bitmap_zero(alloc->table, num);
99	for (i = 0; i < reserved; ++i)
100		set_bit(i, alloc->table);
101
102	return 0;
103}
104
105void mthca_alloc_cleanup(struct mthca_alloc *alloc)
106{
107	kfree(alloc->table);
108}
109
110/*
111 * Array of pointers with lazy allocation of leaf pages.  Callers of
112 * _get, _set and _clear methods must use a lock or otherwise
113 * serialize access to the array.
114 */
115
116#define MTHCA_ARRAY_MASK (PAGE_SIZE / sizeof (void *) - 1)
117
118void *mthca_array_get(struct mthca_array *array, int index)
119{
120	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
121
122	if (array->page_list[p].page)
123		return array->page_list[p].page[index & MTHCA_ARRAY_MASK];
124	else
125		return NULL;
126}
127
128int mthca_array_set(struct mthca_array *array, int index, void *value)
129{
130	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
131
132	/* Allocate with GFP_ATOMIC because we'll be called with locks held. */
133	if (!array->page_list[p].page)
134		array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC);
135
136	if (!array->page_list[p].page)
137		return -ENOMEM;
138
139	array->page_list[p].page[index & MTHCA_ARRAY_MASK] = value;
140	++array->page_list[p].used;
141
142	return 0;
143}
144
145void mthca_array_clear(struct mthca_array *array, int index)
146{
147	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
148
149	if (--array->page_list[p].used == 0) {
150		free_page((unsigned long) array->page_list[p].page);
151		array->page_list[p].page = NULL;
152	} else
153		array->page_list[p].page[index & MTHCA_ARRAY_MASK] = NULL;
154
155	if (array->page_list[p].used < 0)
156		pr_debug("Array %p index %d page %d with ref count %d < 0\n",
157			 array, index, p, array->page_list[p].used);
158}
159
160int mthca_array_init(struct mthca_array *array, int nent)
161{
162	int npage = (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE;
163	int i;
164
165	array->page_list = kmalloc(npage * sizeof *array->page_list, GFP_KERNEL);
166	if (!array->page_list)
167		return -ENOMEM;
168
169	for (i = 0; i < npage; ++i) {
170		array->page_list[i].page = NULL;
171		array->page_list[i].used = 0;
172	}
173
174	return 0;
175}
176
177void mthca_array_cleanup(struct mthca_array *array, int nent)
178{
179	int i;
180
181	for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
182		free_page((unsigned long) array->page_list[i].page);
183
184	kfree(array->page_list);
185}
186
187/*
188 * Handling for queue buffers -- we allocate a bunch of memory and
189 * register it in a memory region at HCA virtual address 0.  If the
190 * requested size is > max_direct, we split the allocation into
191 * multiple pages, so we don't require too much contiguous memory.
192 */
193
194int mthca_buf_alloc(struct mthca_dev *dev, int size, int max_direct,
195		    union mthca_buf *buf, int *is_direct, struct mthca_pd *pd,
196		    int hca_write, struct mthca_mr *mr)
197{
198	int err = -ENOMEM;
199	int npages, shift;
200	u64 *dma_list = NULL;
201	dma_addr_t t;
202	int i;
203
204	if (size <= max_direct) {
205		*is_direct = 1;
206		npages     = 1;
207		shift      = get_order(size) + PAGE_SHIFT;
208
209		buf->direct.buf = dma_alloc_coherent(&dev->pdev->dev,
210						     size, &t, GFP_KERNEL);
211		if (!buf->direct.buf)
212			return -ENOMEM;
213
214		dma_unmap_addr_set(&buf->direct, mapping, t);
215
216		memset(buf->direct.buf, 0, size);
217
218		while (t & ((1 << shift) - 1)) {
219			--shift;
220			npages *= 2;
221		}
222
223		dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
224		if (!dma_list)
225			goto err_free;
226
227		for (i = 0; i < npages; ++i)
228			dma_list[i] = t + i * (1 << shift);
229	} else {
230		*is_direct = 0;
231		npages     = (size + PAGE_SIZE - 1) / PAGE_SIZE;
232		shift      = PAGE_SHIFT;
233
234		dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
235		if (!dma_list)
236			return -ENOMEM;
237
238		buf->page_list = kmalloc(npages * sizeof *buf->page_list,
239					 GFP_KERNEL);
240		if (!buf->page_list)
241			goto err_out;
242
243		for (i = 0; i < npages; ++i)
244			buf->page_list[i].buf = NULL;
245
246		for (i = 0; i < npages; ++i) {
247			buf->page_list[i].buf =
248				dma_alloc_coherent(&dev->pdev->dev, PAGE_SIZE,
249						   &t, GFP_KERNEL);
250			if (!buf->page_list[i].buf)
251				goto err_free;
252
253			dma_list[i] = t;
254			dma_unmap_addr_set(&buf->page_list[i], mapping, t);
255
256			clear_page(buf->page_list[i].buf);
257		}
258	}
259
260	err = mthca_mr_alloc_phys(dev, pd->pd_num,
261				  dma_list, shift, npages,
262				  0, size,
263				  MTHCA_MPT_FLAG_LOCAL_READ |
264				  (hca_write ? MTHCA_MPT_FLAG_LOCAL_WRITE : 0),
265				  mr);
266	if (err)
267		goto err_free;
268
269	kfree(dma_list);
270
271	return 0;
272
273err_free:
274	mthca_buf_free(dev, size, buf, *is_direct, NULL);
275
276err_out:
277	kfree(dma_list);
278
279	return err;
280}
281
282void mthca_buf_free(struct mthca_dev *dev, int size, union mthca_buf *buf,
283		    int is_direct, struct mthca_mr *mr)
284{
285	int i;
286
287	if (mr)
288		mthca_free_mr(dev, mr);
289
290	if (is_direct)
291		dma_free_coherent(&dev->pdev->dev, size, buf->direct.buf,
292				  dma_unmap_addr(&buf->direct, mapping));
293	else {
294		for (i = 0; i < (size + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
295			dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
296					  buf->page_list[i].buf,
297					  dma_unmap_addr(&buf->page_list[i],
298							 mapping));
299		kfree(buf->page_list);
300	}
301}
302