xref: /openbmc/linux/drivers/infiniband/hw/mthca/mthca_allocator.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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  * $Id: mthca_allocator.c 1349 2004-12-16 21:09:43Z roland $
33  */
34 
35 #include <linux/errno.h>
36 #include <linux/slab.h>
37 #include <linux/bitmap.h>
38 
39 #include "mthca_dev.h"
40 
41 /* Trivial bitmap-based allocator */
42 u32 mthca_alloc(struct mthca_alloc *alloc)
43 {
44 	unsigned long flags;
45 	u32 obj;
46 
47 	spin_lock_irqsave(&alloc->lock, flags);
48 
49 	obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last);
50 	if (obj >= alloc->max) {
51 		alloc->top = (alloc->top + alloc->max) & alloc->mask;
52 		obj = find_first_zero_bit(alloc->table, alloc->max);
53 	}
54 
55 	if (obj < alloc->max) {
56 		set_bit(obj, alloc->table);
57 		obj |= alloc->top;
58 	} else
59 		obj = -1;
60 
61 	spin_unlock_irqrestore(&alloc->lock, flags);
62 
63 	return obj;
64 }
65 
66 void mthca_free(struct mthca_alloc *alloc, u32 obj)
67 {
68 	unsigned long flags;
69 
70 	obj &= alloc->max - 1;
71 
72 	spin_lock_irqsave(&alloc->lock, flags);
73 
74 	clear_bit(obj, alloc->table);
75 	alloc->last = min(alloc->last, obj);
76 	alloc->top = (alloc->top + alloc->max) & alloc->mask;
77 
78 	spin_unlock_irqrestore(&alloc->lock, flags);
79 }
80 
81 int mthca_alloc_init(struct mthca_alloc *alloc, u32 num, u32 mask,
82 		     u32 reserved)
83 {
84 	int i;
85 
86 	/* num must be a power of 2 */
87 	if (num != 1 << (ffs(num) - 1))
88 		return -EINVAL;
89 
90 	alloc->last = 0;
91 	alloc->top  = 0;
92 	alloc->max  = num;
93 	alloc->mask = mask;
94 	spin_lock_init(&alloc->lock);
95 	alloc->table = kmalloc(BITS_TO_LONGS(num) * sizeof (long),
96 			       GFP_KERNEL);
97 	if (!alloc->table)
98 		return -ENOMEM;
99 
100 	bitmap_zero(alloc->table, num);
101 	for (i = 0; i < reserved; ++i)
102 		set_bit(i, alloc->table);
103 
104 	return 0;
105 }
106 
107 void mthca_alloc_cleanup(struct mthca_alloc *alloc)
108 {
109 	kfree(alloc->table);
110 }
111 
112 /*
113  * Array of pointers with lazy allocation of leaf pages.  Callers of
114  * _get, _set and _clear methods must use a lock or otherwise
115  * serialize access to the array.
116  */
117 
118 #define MTHCA_ARRAY_MASK (PAGE_SIZE / sizeof (void *) - 1)
119 
120 void *mthca_array_get(struct mthca_array *array, int index)
121 {
122 	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
123 
124 	if (array->page_list[p].page)
125 		return array->page_list[p].page[index & MTHCA_ARRAY_MASK];
126 	else
127 		return NULL;
128 }
129 
130 int mthca_array_set(struct mthca_array *array, int index, void *value)
131 {
132 	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
133 
134 	/* Allocate with GFP_ATOMIC because we'll be called with locks held. */
135 	if (!array->page_list[p].page)
136 		array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC);
137 
138 	if (!array->page_list[p].page)
139 		return -ENOMEM;
140 
141 	array->page_list[p].page[index & MTHCA_ARRAY_MASK] = value;
142 	++array->page_list[p].used;
143 
144 	return 0;
145 }
146 
147 void mthca_array_clear(struct mthca_array *array, int index)
148 {
149 	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
150 
151 	if (--array->page_list[p].used == 0) {
152 		free_page((unsigned long) array->page_list[p].page);
153 		array->page_list[p].page = NULL;
154 	} else
155 		array->page_list[p].page[index & MTHCA_ARRAY_MASK] = NULL;
156 
157 	if (array->page_list[p].used < 0)
158 		pr_debug("Array %p index %d page %d with ref count %d < 0\n",
159 			 array, index, p, array->page_list[p].used);
160 }
161 
162 int mthca_array_init(struct mthca_array *array, int nent)
163 {
164 	int npage = (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE;
165 	int i;
166 
167 	array->page_list = kmalloc(npage * sizeof *array->page_list, GFP_KERNEL);
168 	if (!array->page_list)
169 		return -ENOMEM;
170 
171 	for (i = 0; i < npage; ++i) {
172 		array->page_list[i].page = NULL;
173 		array->page_list[i].used = 0;
174 	}
175 
176 	return 0;
177 }
178 
179 void mthca_array_cleanup(struct mthca_array *array, int nent)
180 {
181 	int i;
182 
183 	for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
184 		free_page((unsigned long) array->page_list[i].page);
185 
186 	kfree(array->page_list);
187 }
188 
189 /*
190  * Handling for queue buffers -- we allocate a bunch of memory and
191  * register it in a memory region at HCA virtual address 0.  If the
192  * requested size is > max_direct, we split the allocation into
193  * multiple pages, so we don't require too much contiguous memory.
194  */
195 
196 int mthca_buf_alloc(struct mthca_dev *dev, int size, int max_direct,
197 		    union mthca_buf *buf, int *is_direct, struct mthca_pd *pd,
198 		    int hca_write, struct mthca_mr *mr)
199 {
200 	int err = -ENOMEM;
201 	int npages, shift;
202 	u64 *dma_list = NULL;
203 	dma_addr_t t;
204 	int i;
205 
206 	if (size <= max_direct) {
207 		*is_direct = 1;
208 		npages     = 1;
209 		shift      = get_order(size) + PAGE_SHIFT;
210 
211 		buf->direct.buf = dma_alloc_coherent(&dev->pdev->dev,
212 						     size, &t, GFP_KERNEL);
213 		if (!buf->direct.buf)
214 			return -ENOMEM;
215 
216 		pci_unmap_addr_set(&buf->direct, mapping, t);
217 
218 		memset(buf->direct.buf, 0, size);
219 
220 		while (t & ((1 << shift) - 1)) {
221 			--shift;
222 			npages *= 2;
223 		}
224 
225 		dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
226 		if (!dma_list)
227 			goto err_free;
228 
229 		for (i = 0; i < npages; ++i)
230 			dma_list[i] = t + i * (1 << shift);
231 	} else {
232 		*is_direct = 0;
233 		npages     = (size + PAGE_SIZE - 1) / PAGE_SIZE;
234 		shift      = PAGE_SHIFT;
235 
236 		dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
237 		if (!dma_list)
238 			return -ENOMEM;
239 
240 		buf->page_list = kmalloc(npages * sizeof *buf->page_list,
241 					 GFP_KERNEL);
242 		if (!buf->page_list)
243 			goto err_out;
244 
245 		for (i = 0; i < npages; ++i)
246 			buf->page_list[i].buf = NULL;
247 
248 		for (i = 0; i < npages; ++i) {
249 			buf->page_list[i].buf =
250 				dma_alloc_coherent(&dev->pdev->dev, PAGE_SIZE,
251 						   &t, GFP_KERNEL);
252 			if (!buf->page_list[i].buf)
253 				goto err_free;
254 
255 			dma_list[i] = t;
256 			pci_unmap_addr_set(&buf->page_list[i], mapping, t);
257 
258 			clear_page(buf->page_list[i].buf);
259 		}
260 	}
261 
262 	err = mthca_mr_alloc_phys(dev, pd->pd_num,
263 				  dma_list, shift, npages,
264 				  0, size,
265 				  MTHCA_MPT_FLAG_LOCAL_READ |
266 				  (hca_write ? MTHCA_MPT_FLAG_LOCAL_WRITE : 0),
267 				  mr);
268 	if (err)
269 		goto err_free;
270 
271 	kfree(dma_list);
272 
273 	return 0;
274 
275 err_free:
276 	mthca_buf_free(dev, size, buf, *is_direct, NULL);
277 
278 err_out:
279 	kfree(dma_list);
280 
281 	return err;
282 }
283 
284 void mthca_buf_free(struct mthca_dev *dev, int size, union mthca_buf *buf,
285 		    int is_direct, struct mthca_mr *mr)
286 {
287 	int i;
288 
289 	if (mr)
290 		mthca_free_mr(dev, mr);
291 
292 	if (is_direct)
293 		dma_free_coherent(&dev->pdev->dev, size, buf->direct.buf,
294 				  pci_unmap_addr(&buf->direct, mapping));
295 	else {
296 		for (i = 0; i < (size + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
297 			dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
298 					  buf->page_list[i].buf,
299 					  pci_unmap_addr(&buf->page_list[i],
300 							 mapping));
301 		kfree(buf->page_list);
302 	}
303 }
304