[linux-2.6-block.git] / drivers / infiniband / hw / vmw_pvrdma / pvrdma_mr.c

/*
 * Copyright (c) 2012-2016 VMware, Inc.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of EITHER the GNU General Public License
 * version 2 as published by the Free Software Foundation or the BSD
 * 2-Clause License. This program is distributed in the hope that it
 * will be useful, but WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License version 2 for more details at
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program available in the file COPYING in the main
 * directory of this source tree.
 *
 * The BSD 2-Clause License
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/list.h>
#include <linux/slab.h>

#include "pvrdma.h"

/**
 * pvrdma_get_dma_mr - get a DMA memory region
 * @pd: protection domain
 * @acc: access flags
 *
 * @return: ib_mr pointer on success, otherwise returns an errno.
 */
struct ib_mr *pvrdma_get_dma_mr(struct ib_pd *pd, int acc)
{
	struct pvrdma_dev *dev = to_vdev(pd->device);
	struct pvrdma_user_mr *mr;
	union pvrdma_cmd_req req;
	union pvrdma_cmd_resp rsp;
	struct pvrdma_cmd_create_mr *cmd = &req.create_mr;
	struct pvrdma_cmd_create_mr_resp *resp = &rsp.create_mr_resp;
	int ret;

	/* Support only LOCAL_WRITE flag for DMA MRs */
	if (acc & ~IB_ACCESS_LOCAL_WRITE) {
		dev_warn(&dev->pdev->dev,
			 "unsupported dma mr access flags %#x\n", acc);
		return ERR_PTR(-EOPNOTSUPP);
	}

	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
	if (!mr)
		return ERR_PTR(-ENOMEM);

	memset(cmd, 0, sizeof(*cmd));
	cmd->hdr.cmd = PVRDMA_CMD_CREATE_MR;
	cmd->pd_handle = to_vpd(pd)->pd_handle;
	cmd->access_flags = acc;
	cmd->flags = PVRDMA_MR_FLAG_DMA;

	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_MR_RESP);
	if (ret < 0) {
		dev_warn(&dev->pdev->dev,
			 "could not get DMA mem region, error: %d\n", ret);
		kfree(mr);
		return ERR_PTR(ret);
	}

	mr->mmr.mr_handle = resp->mr_handle;
	mr->ibmr.lkey = resp->lkey;
	mr->ibmr.rkey = resp->rkey;

	return &mr->ibmr;
}

/**
 * pvrdma_reg_user_mr - register a userspace memory region
 * @pd: protection domain
 * @start: starting address
 * @length: length of region
 * @virt_addr: I/O virtual address
 * @access_flags: access flags for memory region
 * @udata: user data
 *
 * @return: ib_mr pointer on success, otherwise returns an errno.
 */
struct ib_mr *pvrdma_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
				 u64 virt_addr, int access_flags,
				 struct ib_udata *udata)
{
	struct pvrdma_dev *dev = to_vdev(pd->device);
	struct pvrdma_user_mr *mr = NULL;
	struct ib_umem *umem;
	union pvrdma_cmd_req req;
	union pvrdma_cmd_resp rsp;
	struct pvrdma_cmd_create_mr *cmd = &req.create_mr;
	struct pvrdma_cmd_create_mr_resp *resp = &rsp.create_mr_resp;
	int nchunks;
	int ret;
	int entry;
	struct scatterlist *sg;

	if (length == 0 || length > dev->dsr->caps.max_mr_size) {
		dev_warn(&dev->pdev->dev, "invalid mem region length\n");
		return ERR_PTR(-EINVAL);
	}

	umem = ib_umem_get(pd->uobject->context, start,
			   length, access_flags, 0);
	if (IS_ERR(umem)) {
		dev_warn(&dev->pdev->dev,
			 "could not get umem for mem region\n");
		return ERR_CAST(umem);
	}

	nchunks = 0;
	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry)
		nchunks += sg_dma_len(sg) >> PAGE_SHIFT;

	if (nchunks < 0 || nchunks > PVRDMA_PAGE_DIR_MAX_PAGES) {
		dev_warn(&dev->pdev->dev, "overflow %d pages in mem region\n",
			 nchunks);
		ret = -EINVAL;
		goto err_umem;
	}

	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
	if (!mr) {
		ret = -ENOMEM;
		goto err_umem;
	}

	mr->mmr.iova = virt_addr;
	mr->mmr.size = length;
	mr->umem = umem;

	ret = pvrdma_page_dir_init(dev, &mr->pdir, nchunks, false);
	if (ret) {
		dev_warn(&dev->pdev->dev,
			 "could not allocate page directory\n");
		goto err_umem;
	}

	ret = pvrdma_page_dir_insert_umem(&mr->pdir, mr->umem, 0);
	if (ret)
		goto err_pdir;

	memset(cmd, 0, sizeof(*cmd));
	cmd->hdr.cmd = PVRDMA_CMD_CREATE_MR;
	cmd->start = start;
	cmd->length = length;
	cmd->pd_handle = to_vpd(pd)->pd_handle;
	cmd->access_flags = access_flags;
	cmd->nchunks = nchunks;
	cmd->pdir_dma = mr->pdir.dir_dma;

	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_MR_RESP);
	if (ret < 0) {
		dev_warn(&dev->pdev->dev,
			 "could not register mem region, error: %d\n", ret);
		goto err_pdir;
	}

	mr->mmr.mr_handle = resp->mr_handle;
	mr->ibmr.lkey = resp->lkey;
	mr->ibmr.rkey = resp->rkey;

	return &mr->ibmr;

err_pdir:
	pvrdma_page_dir_cleanup(dev, &mr->pdir);
err_umem:
	ib_umem_release(umem);
	kfree(mr);

	return ERR_PTR(ret);
}

/**
 * pvrdma_alloc_mr - allocate a memory region
 * @pd: protection domain
 * @mr_type: type of memory region
 * @max_num_sg: maximum number of pages
 *
 * @return: ib_mr pointer on success, otherwise returns an errno.
 */
struct ib_mr *pvrdma_alloc_mr(struct ib_pd *pd, enum ib_mr_type mr_type,
			      u32 max_num_sg)
{
	struct pvrdma_dev *dev = to_vdev(pd->device);
	struct pvrdma_user_mr *mr;
	union pvrdma_cmd_req req;
	union pvrdma_cmd_resp rsp;
	struct pvrdma_cmd_create_mr *cmd = &req.create_mr;
	struct pvrdma_cmd_create_mr_resp *resp = &rsp.create_mr_resp;
	int size = max_num_sg * sizeof(u64);
	int ret;

	if (mr_type != IB_MR_TYPE_MEM_REG ||
	    max_num_sg > PVRDMA_MAX_FAST_REG_PAGES)
		return ERR_PTR(-EINVAL);

	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
	if (!mr)
		return ERR_PTR(-ENOMEM);

	mr->pages = kzalloc(size, GFP_KERNEL);
	if (!mr->pages) {
		ret = -ENOMEM;
		goto freemr;
	}

	ret = pvrdma_page_dir_init(dev, &mr->pdir, max_num_sg, false);
	if (ret) {
		dev_warn(&dev->pdev->dev,
			 "failed to allocate page dir for mr\n");
		ret = -ENOMEM;
		goto freepages;
	}

	memset(cmd, 0, sizeof(*cmd));
	cmd->hdr.cmd = PVRDMA_CMD_CREATE_MR;
	cmd->pd_handle = to_vpd(pd)->pd_handle;
	cmd->access_flags = 0;
	cmd->flags = PVRDMA_MR_FLAG_FRMR;
	cmd->nchunks = max_num_sg;

	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_MR_RESP);
	if (ret < 0) {
		dev_warn(&dev->pdev->dev,
			 "could not create FR mem region, error: %d\n", ret);
		goto freepdir;
	}

	mr->max_pages = max_num_sg;
	mr->mmr.mr_handle = resp->mr_handle;
	mr->ibmr.lkey = resp->lkey;
	mr->ibmr.rkey = resp->rkey;
	mr->page_shift = PAGE_SHIFT;
	mr->umem = NULL;

	return &mr->ibmr;

freepdir:
	pvrdma_page_dir_cleanup(dev, &mr->pdir);
freepages:
	kfree(mr->pages);
freemr:
	kfree(mr);
	return ERR_PTR(ret);
}

/**
 * pvrdma_dereg_mr - deregister a memory region
 * @ibmr: memory region
 *
 * @return: 0 on success.
 */
int pvrdma_dereg_mr(struct ib_mr *ibmr)
{
	struct pvrdma_user_mr *mr = to_vmr(ibmr);
	struct pvrdma_dev *dev = to_vdev(ibmr->device);
	union pvrdma_cmd_req req;
	struct pvrdma_cmd_destroy_mr *cmd = &req.destroy_mr;
	int ret;

	memset(cmd, 0, sizeof(*cmd));
	cmd->hdr.cmd = PVRDMA_CMD_DESTROY_MR;
	cmd->mr_handle = mr->mmr.mr_handle;
	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
	if (ret < 0)
		dev_warn(&dev->pdev->dev,
			 "could not deregister mem region, error: %d\n", ret);

	pvrdma_page_dir_cleanup(dev, &mr->pdir);
	if (mr->umem)
		ib_umem_release(mr->umem);

	kfree(mr->pages);
	kfree(mr);

	return 0;
}

static int pvrdma_set_page(struct ib_mr *ibmr, u64 addr)
{
	struct pvrdma_user_mr *mr = to_vmr(ibmr);

	if (mr->npages == mr->max_pages)
		return -ENOMEM;

	mr->pages[mr->npages++] = addr;
	return 0;
}

int pvrdma_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg, int sg_nents,
		     unsigned int *sg_offset)
{
	struct pvrdma_user_mr *mr = to_vmr(ibmr);
	struct pvrdma_dev *dev = to_vdev(ibmr->device);
	int ret;

	mr->npages = 0;

	ret = ib_sg_to_pages(ibmr, sg, sg_nents, sg_offset, pvrdma_set_page);
	if (ret < 0)
		dev_warn(&dev->pdev->dev, "could not map sg to pages\n");

	return ret;
}
Commit	Line	Data
29c8d9eb AR	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 nchunks;
123	int ret;
124	int entry;
125	struct scatterlist *sg;
126
127	if (length == 0 \|\| length > dev->dsr->caps.max_mr_size) {
128	dev_warn(&dev->pdev->dev, "invalid mem region length\n");
129	return ERR_PTR(-EINVAL);
130	}
131
132	umem = ib_umem_get(pd->uobject->context, start,
133	length, access_flags, 0);
134	if (IS_ERR(umem)) {
135	dev_warn(&dev->pdev->dev,
136	"could not get umem for mem region\n");
137	return ERR_CAST(umem);
138	}
139
140	nchunks = 0;
141	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry)
142	nchunks += sg_dma_len(sg) >> PAGE_SHIFT;
143
144	if (nchunks < 0 \|\| nchunks > PVRDMA_PAGE_DIR_MAX_PAGES) {
145	dev_warn(&dev->pdev->dev, "overflow %d pages in mem region\n",
146	nchunks);
147	ret = -EINVAL;
148	goto err_umem;
149	}
150
151	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
152	if (!mr) {
153	ret = -ENOMEM;
154	goto err_umem;
155	}
156
157	mr->mmr.iova = virt_addr;
158	mr->mmr.size = length;
159	mr->umem = umem;
160
161	ret = pvrdma_page_dir_init(dev, &mr->pdir, nchunks, false);
162	if (ret) {
163	dev_warn(&dev->pdev->dev,
164	"could not allocate page directory\n");
165	goto err_umem;
166	}
167
168	ret = pvrdma_page_dir_insert_umem(&mr->pdir, mr->umem, 0);
169	if (ret)
170	goto err_pdir;
171
172	memset(cmd, 0, sizeof(*cmd));
173	cmd->hdr.cmd = PVRDMA_CMD_CREATE_MR;
174	cmd->start = start;
175	cmd->length = length;
176	cmd->pd_handle = to_vpd(pd)->pd_handle;
177	cmd->access_flags = access_flags;
178	cmd->nchunks = nchunks;
179	cmd->pdir_dma = mr->pdir.dir_dma;
180
181	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_MR_RESP);
182	if (ret < 0) {
183	dev_warn(&dev->pdev->dev,
184	"could not register mem region, error: %d\n", ret);
185	goto err_pdir;
186	}
187
188	mr->mmr.mr_handle = resp->mr_handle;
189	mr->ibmr.lkey = resp->lkey;
190	mr->ibmr.rkey = resp->rkey;
191
192	return &mr->ibmr;
193
194	err_pdir:
195	pvrdma_page_dir_cleanup(dev, &mr->pdir);
196	err_umem:
197	ib_umem_release(umem);
198	kfree(mr);
199
200	return ERR_PTR(ret);
201	}
202
203	/**
204	* pvrdma_alloc_mr - allocate a memory region
205	* @pd: protection domain
206	* @mr_type: type of memory region
207	* @max_num_sg: maximum number of pages
208	*
209	* @return: ib_mr pointer on success, otherwise returns an errno.
210	*/
211	struct ib_mr pvrdma_alloc_mr(struct ib_pd pd, enum ib_mr_type mr_type,
212	u32 max_num_sg)
213	{
214	struct pvrdma_dev *dev = to_vdev(pd->device);
215	struct pvrdma_user_mr *mr;
216	union pvrdma_cmd_req req;
217	union pvrdma_cmd_resp rsp;
218	struct pvrdma_cmd_create_mr *cmd = &req.create_mr;
219	struct pvrdma_cmd_create_mr_resp *resp = &rsp.create_mr_resp;
220	int size = max_num_sg * sizeof(u64);
221	int ret;
222
223	if (mr_type != IB_MR_TYPE_MEM_REG \|\|
224	max_num_sg > PVRDMA_MAX_FAST_REG_PAGES)
225	return ERR_PTR(-EINVAL);
226
227	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
228	if (!mr)
229	return ERR_PTR(-ENOMEM);
230
231	mr->pages = kzalloc(size, GFP_KERNEL);
232	if (!mr->pages) {
233	ret = -ENOMEM;
234	goto freemr;
235	}
236
237	ret = pvrdma_page_dir_init(dev, &mr->pdir, max_num_sg, false);
238	if (ret) {
239	dev_warn(&dev->pdev->dev,
240	"failed to allocate page dir for mr\n");
241	ret = -ENOMEM;
242	goto freepages;
243	}
244
245	memset(cmd, 0, sizeof(*cmd));
246	cmd->hdr.cmd = PVRDMA_CMD_CREATE_MR;
247	cmd->pd_handle = to_vpd(pd)->pd_handle;
248	cmd->access_flags = 0;
249	cmd->flags = PVRDMA_MR_FLAG_FRMR;
250	cmd->nchunks = max_num_sg;
251
252	ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_MR_RESP);
253	if (ret < 0) {
254	dev_warn(&dev->pdev->dev,
255	"could not create FR mem region, error: %d\n", ret);
256	goto freepdir;
257	}
258
259	mr->max_pages = max_num_sg;
260	mr->mmr.mr_handle = resp->mr_handle;
261	mr->ibmr.lkey = resp->lkey;
262	mr->ibmr.rkey = resp->rkey;
263	mr->page_shift = PAGE_SHIFT;
264	mr->umem = NULL;
265
266	return &mr->ibmr;
267
268	freepdir:
269	pvrdma_page_dir_cleanup(dev, &mr->pdir);
270	freepages:
271	kfree(mr->pages);
272	freemr:
273	kfree(mr);
274	return ERR_PTR(ret);
275	}
276
277	/**
278	* pvrdma_dereg_mr - deregister a memory region
279	* @ibmr: memory region
280	*
281	* @return: 0 on success.
282	*/
283	int pvrdma_dereg_mr(struct ib_mr *ibmr)
284	{
285	struct pvrdma_user_mr *mr = to_vmr(ibmr);
286	struct pvrdma_dev *dev = to_vdev(ibmr->device);
287	union pvrdma_cmd_req req;
288	struct pvrdma_cmd_destroy_mr *cmd = &req.destroy_mr;
289	int ret;
290
291	memset(cmd, 0, sizeof(*cmd));
292	cmd->hdr.cmd = PVRDMA_CMD_DESTROY_MR;
293	cmd->mr_handle = mr->mmr.mr_handle;
294	ret = pvrdma_cmd_post(dev, &req, NULL, 0);
295	if (ret < 0)
296	dev_warn(&dev->pdev->dev,
297	"could not deregister mem region, error: %d\n", ret);
298
299	pvrdma_page_dir_cleanup(dev, &mr->pdir);
300	if (mr->umem)
301	ib_umem_release(mr->umem);
302
303	kfree(mr->pages);
304	kfree(mr);
305
306	return 0;
307	}
308
309	static int pvrdma_set_page(struct ib_mr *ibmr, u64 addr)
310	{
311	struct pvrdma_user_mr *mr = to_vmr(ibmr);
312
313	if (mr->npages == mr->max_pages)
314	return -ENOMEM;
315
316	mr->pages[mr->npages++] = addr;
317	return 0;
318	}
319
320	int pvrdma_map_mr_sg(struct ib_mr ibmr, struct scatterlist sg, int sg_nents,
321	unsigned int *sg_offset)
322	{
323	struct pvrdma_user_mr *mr = to_vmr(ibmr);
324	struct pvrdma_dev *dev = to_vdev(ibmr->device);
325	int ret;
326
327	mr->npages = 0;
328
329	ret = ib_sg_to_pages(ibmr, sg, sg_nents, sg_offset, pvrdma_set_page);
330	if (ret < 0)
331	dev_warn(&dev->pdev->dev, "could not map sg to pages\n");
332
333	return ret;
334	}