1 /*
2  * Copyright (c) 2016 Oracle.  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 "ib_mr.h"
34 
rds_ib_alloc_fmr(struct rds_ib_device * rds_ibdev,int npages)35 struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev, int npages)
36 {
37 	struct rds_ib_mr_pool *pool;
38 	struct rds_ib_mr *ibmr = NULL;
39 	struct rds_ib_fmr *fmr;
40 	int err = 0;
41 
42 	if (npages <= RDS_MR_8K_MSG_SIZE)
43 		pool = rds_ibdev->mr_8k_pool;
44 	else
45 		pool = rds_ibdev->mr_1m_pool;
46 
47 	ibmr = rds_ib_try_reuse_ibmr(pool);
48 	if (ibmr)
49 		return ibmr;
50 
51 	ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
52 			    rdsibdev_to_node(rds_ibdev));
53 	if (!ibmr) {
54 		err = -ENOMEM;
55 		goto out_no_cigar;
56 	}
57 
58 	fmr = &ibmr->u.fmr;
59 	fmr->fmr = ib_alloc_fmr(rds_ibdev->pd,
60 			(IB_ACCESS_LOCAL_WRITE |
61 			 IB_ACCESS_REMOTE_READ |
62 			 IB_ACCESS_REMOTE_WRITE |
63 			 IB_ACCESS_REMOTE_ATOMIC),
64 			&pool->fmr_attr);
65 	if (IS_ERR(fmr->fmr)) {
66 		err = PTR_ERR(fmr->fmr);
67 		fmr->fmr = NULL;
68 		pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, err);
69 		goto out_no_cigar;
70 	}
71 
72 	ibmr->pool = pool;
73 	if (pool->pool_type == RDS_IB_MR_8K_POOL)
74 		rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
75 	else
76 		rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);
77 
78 	return ibmr;
79 
80 out_no_cigar:
81 	kfree(ibmr);
82 	atomic_dec(&pool->item_count);
83 
84 	return ERR_PTR(err);
85 }
86 
rds_ib_map_fmr(struct rds_ib_device * rds_ibdev,struct rds_ib_mr * ibmr,struct scatterlist * sg,unsigned int nents)87 static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev,
88 			  struct rds_ib_mr *ibmr, struct scatterlist *sg,
89 			  unsigned int nents)
90 {
91 	struct ib_device *dev = rds_ibdev->dev;
92 	struct rds_ib_fmr *fmr = &ibmr->u.fmr;
93 	struct scatterlist *scat = sg;
94 	u64 io_addr = 0;
95 	u64 *dma_pages;
96 	u32 len;
97 	int page_cnt, sg_dma_len;
98 	int i, j;
99 	int ret;
100 
101 	sg_dma_len = ib_dma_map_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
102 	if (unlikely(!sg_dma_len)) {
103 		pr_warn("RDS/IB: %s failed!\n", __func__);
104 		return -EBUSY;
105 	}
106 
107 	len = 0;
108 	page_cnt = 0;
109 
110 	for (i = 0; i < sg_dma_len; ++i) {
111 		unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]);
112 		u64 dma_addr = ib_sg_dma_address(dev, &scat[i]);
113 
114 		if (dma_addr & ~PAGE_MASK) {
115 			if (i > 0) {
116 				ib_dma_unmap_sg(dev, sg, nents,
117 						DMA_BIDIRECTIONAL);
118 				return -EINVAL;
119 			} else {
120 				++page_cnt;
121 			}
122 		}
123 		if ((dma_addr + dma_len) & ~PAGE_MASK) {
124 			if (i < sg_dma_len - 1) {
125 				ib_dma_unmap_sg(dev, sg, nents,
126 						DMA_BIDIRECTIONAL);
127 				return -EINVAL;
128 			} else {
129 				++page_cnt;
130 			}
131 		}
132 
133 		len += dma_len;
134 	}
135 
136 	page_cnt += len >> PAGE_SHIFT;
137 	if (page_cnt > ibmr->pool->fmr_attr.max_pages) {
138 		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
139 		return -EINVAL;
140 	}
141 
142 	dma_pages = kmalloc_array_node(sizeof(u64), page_cnt, GFP_ATOMIC,
143 				       rdsibdev_to_node(rds_ibdev));
144 	if (!dma_pages) {
145 		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
146 		return -ENOMEM;
147 	}
148 
149 	page_cnt = 0;
150 	for (i = 0; i < sg_dma_len; ++i) {
151 		unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]);
152 		u64 dma_addr = ib_sg_dma_address(dev, &scat[i]);
153 
154 		for (j = 0; j < dma_len; j += PAGE_SIZE)
155 			dma_pages[page_cnt++] =
156 				(dma_addr & PAGE_MASK) + j;
157 	}
158 
159 	ret = ib_map_phys_fmr(fmr->fmr, dma_pages, page_cnt, io_addr);
160 	if (ret) {
161 		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
162 		goto out;
163 	}
164 
165 	/* Success - we successfully remapped the MR, so we can
166 	 * safely tear down the old mapping.
167 	 */
168 	rds_ib_teardown_mr(ibmr);
169 
170 	ibmr->sg = scat;
171 	ibmr->sg_len = nents;
172 	ibmr->sg_dma_len = sg_dma_len;
173 	ibmr->remap_count++;
174 
175 	if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
176 		rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
177 	else
178 		rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
179 	ret = 0;
180 
181 out:
182 	kfree(dma_pages);
183 
184 	return ret;
185 }
186 
rds_ib_reg_fmr(struct rds_ib_device * rds_ibdev,struct scatterlist * sg,unsigned long nents,u32 * key)187 struct rds_ib_mr *rds_ib_reg_fmr(struct rds_ib_device *rds_ibdev,
188 				 struct scatterlist *sg,
189 				 unsigned long nents,
190 				 u32 *key)
191 {
192 	struct rds_ib_mr *ibmr = NULL;
193 	struct rds_ib_fmr *fmr;
194 	int ret;
195 
196 	ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
197 	if (IS_ERR(ibmr))
198 		return ibmr;
199 
200 	ibmr->device = rds_ibdev;
201 	fmr = &ibmr->u.fmr;
202 	ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
203 	if (ret == 0)
204 		*key = fmr->fmr->rkey;
205 	else
206 		rds_ib_free_mr(ibmr, 0);
207 
208 	return ibmr;
209 }
210 
rds_ib_unreg_fmr(struct list_head * list,unsigned int * nfreed,unsigned long * unpinned,unsigned int goal)211 void rds_ib_unreg_fmr(struct list_head *list, unsigned int *nfreed,
212 		      unsigned long *unpinned, unsigned int goal)
213 {
214 	struct rds_ib_mr *ibmr, *next;
215 	struct rds_ib_fmr *fmr;
216 	LIST_HEAD(fmr_list);
217 	int ret = 0;
218 	unsigned int freed = *nfreed;
219 
220 	/* String all ib_mr's onto one list and hand them to  ib_unmap_fmr */
221 	list_for_each_entry(ibmr, list, unmap_list) {
222 		fmr = &ibmr->u.fmr;
223 		list_add(&fmr->fmr->list, &fmr_list);
224 	}
225 
226 	ret = ib_unmap_fmr(&fmr_list);
227 	if (ret)
228 		pr_warn("RDS/IB: FMR invalidation failed (err=%d)\n", ret);
229 
230 	/* Now we can destroy the DMA mapping and unpin any pages */
231 	list_for_each_entry_safe(ibmr, next, list, unmap_list) {
232 		fmr = &ibmr->u.fmr;
233 		*unpinned += ibmr->sg_len;
234 		__rds_ib_teardown_mr(ibmr);
235 		if (freed < goal ||
236 		    ibmr->remap_count >= ibmr->pool->fmr_attr.max_maps) {
237 			if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
238 				rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
239 			else
240 				rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
241 			list_del(&ibmr->unmap_list);
242 			ib_dealloc_fmr(fmr->fmr);
243 			kfree(ibmr);
244 			freed++;
245 		}
246 	}
247 	*nfreed = freed;
248 }
249 
rds_ib_free_fmr_list(struct rds_ib_mr * ibmr)250 void rds_ib_free_fmr_list(struct rds_ib_mr *ibmr)
251 {
252 	struct rds_ib_mr_pool *pool = ibmr->pool;
253 
254 	if (ibmr->remap_count >= pool->fmr_attr.max_maps)
255 		llist_add(&ibmr->llnode, &pool->drop_list);
256 	else
257 		llist_add(&ibmr->llnode, &pool->free_list);
258 }
259