1 /*
2  * Copyright (c) 2012-2016 VMware, Inc.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of EITHER the GNU General Public License
6  * version 2 as published by the Free Software Foundation or the BSD
7  * 2-Clause License. This program is distributed in the hope that it
8  * will be useful, but WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED
9  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
10  * See the GNU General Public License version 2 for more details at
11  * http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program available in the file COPYING in the main
15  * directory of this source tree.
16  *
17  * The BSD 2-Clause License
18  *
19  *     Redistribution and use in source and binary forms, with or
20  *     without modification, are permitted provided that the following
21  *     conditions are met:
22  *
23  *      - Redistributions of source code must retain the above
24  *        copyright notice, this list of conditions and the following
25  *        disclaimer.
26  *
27  *      - Redistributions in binary form must reproduce the above
28  *        copyright notice, this list of conditions and the following
29  *        disclaimer in the documentation and/or other materials
30  *        provided with the distribution.
31  *
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
35  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
36  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
37  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
38  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
39  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
42  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
43  * OF THE POSSIBILITY OF SUCH DAMAGE.
44  */
45 
46 #include <linux/list.h>
47 #include <linux/slab.h>
48 
49 #include "pvrdma.h"
50 
51 /**
52  * pvrdma_get_dma_mr - get a DMA memory region
53  * @pd: protection domain
54  * @acc: access flags
55  *
56  * @return: ib_mr pointer on success, otherwise returns an errno.
57  */
58 struct ib_mr *pvrdma_get_dma_mr(struct ib_pd *pd, int acc)
59 {
60 	struct pvrdma_dev *dev = to_vdev(pd->device);
61 	struct pvrdma_user_mr *mr;
62 	union pvrdma_cmd_req req;
63 	union pvrdma_cmd_resp rsp;
64 	struct pvrdma_cmd_create_mr *cmd = &req.create_mr;
65 	struct pvrdma_cmd_create_mr_resp *resp = &rsp.create_mr_resp;
66 	int ret;
67 
68 	/* Support only LOCAL_WRITE flag for DMA MRs */
69 	if (acc & ~IB_ACCESS_LOCAL_WRITE) {
70 		dev_warn(&dev->pdev->dev,
71 			 "unsupported dma mr access flags %#x\n", acc);
72 		return ERR_PTR(-EOPNOTSUPP);
73 	}
74 
75 	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
76 	if (!mr)
77 		return ERR_PTR(-ENOMEM);
78 
79 	memset(cmd, 0, sizeof(*cmd));
80 	cmd->hdr.cmd = PVRDMA_CMD_CREATE_MR;
81 	cmd->pd_handle = to_vpd(pd)->pd_handle;
82 	cmd->access_flags = acc;
83 	cmd->flags = PVRDMA_MR_FLAG_DMA;
84 
85 	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_MR_RESP);
86 	if (ret < 0) {
87 		dev_warn(&dev->pdev->dev,
88 			 "could not get DMA mem region, error: %d\n", ret);
89 		kfree(mr);
90 		return ERR_PTR(ret);
91 	}
92 
93 	mr->mmr.mr_handle = resp->mr_handle;
94 	mr->ibmr.lkey = resp->lkey;
95 	mr->ibmr.rkey = resp->rkey;
96 
97 	return &mr->ibmr;
98 }
99 
100 /**
101  * pvrdma_reg_user_mr - register a userspace memory region
102  * @pd: protection domain
103  * @start: starting address
104  * @length: length of region
105  * @virt_addr: I/O virtual address
106  * @access_flags: access flags for memory region
107  * @udata: user data
108  *
109  * @return: ib_mr pointer on success, otherwise returns an errno.
110  */
111 struct ib_mr *pvrdma_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
112 				 u64 virt_addr, int access_flags,
113 				 struct ib_udata *udata)
114 {
115 	struct pvrdma_dev *dev = to_vdev(pd->device);
116 	struct pvrdma_user_mr *mr = NULL;
117 	struct ib_umem *umem;
118 	union pvrdma_cmd_req req;
119 	union pvrdma_cmd_resp rsp;
120 	struct pvrdma_cmd_create_mr *cmd = &req.create_mr;
121 	struct pvrdma_cmd_create_mr_resp *resp = &rsp.create_mr_resp;
122 	int ret;
123 
124 	if (length == 0 || length > dev->dsr->caps.max_mr_size) {
125 		dev_warn(&dev->pdev->dev, "invalid mem region length\n");
126 		return ERR_PTR(-EINVAL);
127 	}
128 
129 	umem = ib_umem_get(pd->uobject->context, start,
130 			   length, access_flags, 0);
131 	if (IS_ERR(umem)) {
132 		dev_warn(&dev->pdev->dev,
133 			 "could not get umem for mem region\n");
134 		return ERR_CAST(umem);
135 	}
136 
137 	if (umem->npages < 0 || umem->npages > PVRDMA_PAGE_DIR_MAX_PAGES) {
138 		dev_warn(&dev->pdev->dev, "overflow %d pages in mem region\n",
139 			 umem->npages);
140 		ret = -EINVAL;
141 		goto err_umem;
142 	}
143 
144 	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
145 	if (!mr) {
146 		ret = -ENOMEM;
147 		goto err_umem;
148 	}
149 
150 	mr->mmr.iova = virt_addr;
151 	mr->mmr.size = length;
152 	mr->umem = umem;
153 
154 	ret = pvrdma_page_dir_init(dev, &mr->pdir, umem->npages, false);
155 	if (ret) {
156 		dev_warn(&dev->pdev->dev,
157 			 "could not allocate page directory\n");
158 		goto err_umem;
159 	}
160 
161 	ret = pvrdma_page_dir_insert_umem(&mr->pdir, mr->umem, 0);
162 	if (ret)
163 		goto err_pdir;
164 
165 	memset(cmd, 0, sizeof(*cmd));
166 	cmd->hdr.cmd = PVRDMA_CMD_CREATE_MR;
167 	cmd->start = start;
168 	cmd->length = length;
169 	cmd->pd_handle = to_vpd(pd)->pd_handle;
170 	cmd->access_flags = access_flags;
171 	cmd->nchunks = umem->npages;
172 	cmd->pdir_dma = mr->pdir.dir_dma;
173 
174 	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_MR_RESP);
175 	if (ret < 0) {
176 		dev_warn(&dev->pdev->dev,
177 			 "could not register mem region, error: %d\n", ret);
178 		goto err_pdir;
179 	}
180 
181 	mr->mmr.mr_handle = resp->mr_handle;
182 	mr->ibmr.lkey = resp->lkey;
183 	mr->ibmr.rkey = resp->rkey;
184 
185 	return &mr->ibmr;
186 
187 err_pdir:
188 	pvrdma_page_dir_cleanup(dev, &mr->pdir);
189 err_umem:
190 	ib_umem_release(umem);
191 	kfree(mr);
192 
193 	return ERR_PTR(ret);
194 }
195 
196 /**
197  * pvrdma_alloc_mr - allocate a memory region
198  * @pd: protection domain
199  * @mr_type: type of memory region
200  * @max_num_sg: maximum number of pages
201  *
202  * @return: ib_mr pointer on success, otherwise returns an errno.
203  */
204 struct ib_mr *pvrdma_alloc_mr(struct ib_pd *pd, enum ib_mr_type mr_type,
205 			      u32 max_num_sg)
206 {
207 	struct pvrdma_dev *dev = to_vdev(pd->device);
208 	struct pvrdma_user_mr *mr;
209 	union pvrdma_cmd_req req;
210 	union pvrdma_cmd_resp rsp;
211 	struct pvrdma_cmd_create_mr *cmd = &req.create_mr;
212 	struct pvrdma_cmd_create_mr_resp *resp = &rsp.create_mr_resp;
213 	int size = max_num_sg * sizeof(u64);
214 	int ret;
215 
216 	if (mr_type != IB_MR_TYPE_MEM_REG ||
217 	    max_num_sg > PVRDMA_MAX_FAST_REG_PAGES)
218 		return ERR_PTR(-EINVAL);
219 
220 	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
221 	if (!mr)
222 		return ERR_PTR(-ENOMEM);
223 
224 	mr->pages = kzalloc(size, GFP_KERNEL);
225 	if (!mr->pages) {
226 		ret = -ENOMEM;
227 		goto freemr;
228 	}
229 
230 	ret = pvrdma_page_dir_init(dev, &mr->pdir, max_num_sg, false);
231 	if (ret) {
232 		dev_warn(&dev->pdev->dev,
233 			 "failed to allocate page dir for mr\n");
234 		ret = -ENOMEM;
235 		goto freepages;
236 	}
237 
238 	memset(cmd, 0, sizeof(*cmd));
239 	cmd->hdr.cmd = PVRDMA_CMD_CREATE_MR;
240 	cmd->pd_handle = to_vpd(pd)->pd_handle;
241 	cmd->access_flags = 0;
242 	cmd->flags = PVRDMA_MR_FLAG_FRMR;
243 	cmd->nchunks = max_num_sg;
244 
245 	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_MR_RESP);
246 	if (ret < 0) {
247 		dev_warn(&dev->pdev->dev,
248 			 "could not create FR mem region, error: %d\n", ret);
249 		goto freepdir;
250 	}
251 
252 	mr->max_pages = max_num_sg;
253 	mr->mmr.mr_handle = resp->mr_handle;
254 	mr->ibmr.lkey = resp->lkey;
255 	mr->ibmr.rkey = resp->rkey;
256 	mr->page_shift = PAGE_SHIFT;
257 	mr->umem = NULL;
258 
259 	return &mr->ibmr;
260 
261 freepdir:
262 	pvrdma_page_dir_cleanup(dev, &mr->pdir);
263 freepages:
264 	kfree(mr->pages);
265 freemr:
266 	kfree(mr);
267 	return ERR_PTR(ret);
268 }
269 
270 /**
271  * pvrdma_dereg_mr - deregister a memory region
272  * @ibmr: memory region
273  *
274  * @return: 0 on success.
275  */
276 int pvrdma_dereg_mr(struct ib_mr *ibmr)
277 {
278 	struct pvrdma_user_mr *mr = to_vmr(ibmr);
279 	struct pvrdma_dev *dev = to_vdev(ibmr->device);
280 	union pvrdma_cmd_req req;
281 	struct pvrdma_cmd_destroy_mr *cmd = &req.destroy_mr;
282 	int ret;
283 
284 	memset(cmd, 0, sizeof(*cmd));
285 	cmd->hdr.cmd = PVRDMA_CMD_DESTROY_MR;
286 	cmd->mr_handle = mr->mmr.mr_handle;
287 	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
288 	if (ret < 0)
289 		dev_warn(&dev->pdev->dev,
290 			 "could not deregister mem region, error: %d\n", ret);
291 
292 	pvrdma_page_dir_cleanup(dev, &mr->pdir);
293 	if (mr->umem)
294 		ib_umem_release(mr->umem);
295 
296 	kfree(mr->pages);
297 	kfree(mr);
298 
299 	return 0;
300 }
301 
302 static int pvrdma_set_page(struct ib_mr *ibmr, u64 addr)
303 {
304 	struct pvrdma_user_mr *mr = to_vmr(ibmr);
305 
306 	if (mr->npages == mr->max_pages)
307 		return -ENOMEM;
308 
309 	mr->pages[mr->npages++] = addr;
310 	return 0;
311 }
312 
313 int pvrdma_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg, int sg_nents,
314 		     unsigned int *sg_offset)
315 {
316 	struct pvrdma_user_mr *mr = to_vmr(ibmr);
317 	struct pvrdma_dev *dev = to_vdev(ibmr->device);
318 	int ret;
319 
320 	mr->npages = 0;
321 
322 	ret = ib_sg_to_pages(ibmr, sg, sg_nents, sg_offset, pvrdma_set_page);
323 	if (ret < 0)
324 		dev_warn(&dev->pdev->dev, "could not map sg to pages\n");
325 
326 	return ret;
327 }
328