xref: /linux/drivers/infiniband/hw/mlx5/mem.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /*
2  * Copyright (c) 2013-2015, Mellanox Technologies. 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/module.h>
34 #include <rdma/ib_umem.h>
35 #include <rdma/ib_umem_odp.h>
36 #include "mlx5_ib.h"
37 
38 /* @umem: umem object to scan
39  * @addr: ib virtual address requested by the user
40  * @count: number of PAGE_SIZE pages covered by umem
41  * @shift: page shift for the compound pages found in the region
42  * @ncont: number of compund pages
43  * @order: log2 of the number of compound pages
44  */
45 void mlx5_ib_cont_pages(struct ib_umem *umem, u64 addr, int *count, int *shift,
46 			int *ncont, int *order)
47 {
48 	unsigned long tmp;
49 	unsigned long m;
50 	int i, k;
51 	u64 base = 0;
52 	int p = 0;
53 	int skip;
54 	int mask;
55 	u64 len;
56 	u64 pfn;
57 	struct scatterlist *sg;
58 	int entry;
59 	unsigned long page_shift = ilog2(umem->page_size);
60 
61 	/* With ODP we must always match OS page size. */
62 	if (umem->odp_data) {
63 		*count = ib_umem_page_count(umem);
64 		*shift = PAGE_SHIFT;
65 		*ncont = *count;
66 		if (order)
67 			*order = ilog2(roundup_pow_of_two(*count));
68 
69 		return;
70 	}
71 
72 	addr = addr >> page_shift;
73 	tmp = (unsigned long)addr;
74 	m = find_first_bit(&tmp, sizeof(tmp));
75 	skip = 1 << m;
76 	mask = skip - 1;
77 	i = 0;
78 	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
79 		len = sg_dma_len(sg) >> page_shift;
80 		pfn = sg_dma_address(sg) >> page_shift;
81 		for (k = 0; k < len; k++) {
82 			if (!(i & mask)) {
83 				tmp = (unsigned long)pfn;
84 				m = min_t(unsigned long, m, find_first_bit(&tmp, sizeof(tmp)));
85 				skip = 1 << m;
86 				mask = skip - 1;
87 				base = pfn;
88 				p = 0;
89 			} else {
90 				if (base + p != pfn) {
91 					tmp = (unsigned long)p;
92 					m = find_first_bit(&tmp, sizeof(tmp));
93 					skip = 1 << m;
94 					mask = skip - 1;
95 					base = pfn;
96 					p = 0;
97 				}
98 			}
99 			p++;
100 			i++;
101 		}
102 	}
103 
104 	if (i) {
105 		m = min_t(unsigned long, ilog2(roundup_pow_of_two(i)), m);
106 
107 		if (order)
108 			*order = ilog2(roundup_pow_of_two(i) >> m);
109 
110 		*ncont = DIV_ROUND_UP(i, (1 << m));
111 	} else {
112 		m  = 0;
113 
114 		if (order)
115 			*order = 0;
116 
117 		*ncont = 0;
118 	}
119 	*shift = page_shift + m;
120 	*count = i;
121 }
122 
123 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
124 static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
125 {
126 	u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
127 
128 	if (umem_dma & ODP_READ_ALLOWED_BIT)
129 		mtt_entry |= MLX5_IB_MTT_READ;
130 	if (umem_dma & ODP_WRITE_ALLOWED_BIT)
131 		mtt_entry |= MLX5_IB_MTT_WRITE;
132 
133 	return mtt_entry;
134 }
135 #endif
136 
137 /*
138  * Populate the given array with bus addresses from the umem.
139  *
140  * dev - mlx5_ib device
141  * umem - umem to use to fill the pages
142  * page_shift - determines the page size used in the resulting array
143  * offset - offset into the umem to start from,
144  *          only implemented for ODP umems
145  * num_pages - total number of pages to fill
146  * pas - bus addresses array to fill
147  * access_flags - access flags to set on all present pages.
148 		  use enum mlx5_ib_mtt_access_flags for this.
149  */
150 void __mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
151 			    int page_shift, size_t offset, size_t num_pages,
152 			    __be64 *pas, int access_flags)
153 {
154 	unsigned long umem_page_shift = ilog2(umem->page_size);
155 	int shift = page_shift - umem_page_shift;
156 	int mask = (1 << shift) - 1;
157 	int i, k;
158 	u64 cur = 0;
159 	u64 base;
160 	int len;
161 	struct scatterlist *sg;
162 	int entry;
163 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
164 	const bool odp = umem->odp_data != NULL;
165 
166 	if (odp) {
167 		WARN_ON(shift != 0);
168 		WARN_ON(access_flags != (MLX5_IB_MTT_READ | MLX5_IB_MTT_WRITE));
169 
170 		for (i = 0; i < num_pages; ++i) {
171 			dma_addr_t pa = umem->odp_data->dma_list[offset + i];
172 
173 			pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
174 		}
175 		return;
176 	}
177 #endif
178 
179 	i = 0;
180 	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
181 		len = sg_dma_len(sg) >> umem_page_shift;
182 		base = sg_dma_address(sg);
183 		for (k = 0; k < len; k++) {
184 			if (!(i & mask)) {
185 				cur = base + (k << umem_page_shift);
186 				cur |= access_flags;
187 
188 				pas[i >> shift] = cpu_to_be64(cur);
189 				mlx5_ib_dbg(dev, "pas[%d] 0x%llx\n",
190 					    i >> shift, be64_to_cpu(pas[i >> shift]));
191 			}  else
192 				mlx5_ib_dbg(dev, "=====> 0x%llx\n",
193 					    base + (k << umem_page_shift));
194 			i++;
195 		}
196 	}
197 }
198 
199 void mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
200 			  int page_shift, __be64 *pas, int access_flags)
201 {
202 	return __mlx5_ib_populate_pas(dev, umem, page_shift, 0,
203 				      ib_umem_num_pages(umem), pas,
204 				      access_flags);
205 }
206 int mlx5_ib_get_buf_offset(u64 addr, int page_shift, u32 *offset)
207 {
208 	u64 page_size;
209 	u64 page_mask;
210 	u64 off_size;
211 	u64 off_mask;
212 	u64 buf_off;
213 
214 	page_size = (u64)1 << page_shift;
215 	page_mask = page_size - 1;
216 	buf_off = addr & page_mask;
217 	off_size = page_size >> 6;
218 	off_mask = off_size - 1;
219 
220 	if (buf_off & off_mask)
221 		return -EINVAL;
222 
223 	*offset = buf_off >> ilog2(off_size);
224 	return 0;
225 }
226