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eb8ffbfe RD |
1 | /* |
2 | * Copyright (c) 2005 Topspin Communications. All rights reserved. | |
3 | * Copyright (c) 2005 Cisco Systems. All rights reserved. | |
2a1d9b7f | 4 | * Copyright (c) 2005 Mellanox Technologies. All rights reserved. |
eb8ffbfe RD |
5 | * |
6 | * This software is available to you under a choice of one of two | |
7 | * licenses. You may choose to be licensed under the terms of the GNU | |
8 | * General Public License (GPL) Version 2, available from the file | |
9 | * COPYING in the main directory of this source tree, or the | |
10 | * OpenIB.org BSD license below: | |
11 | * | |
12 | * Redistribution and use in source and binary forms, with or | |
13 | * without modification, are permitted provided that the following | |
14 | * conditions are met: | |
15 | * | |
16 | * - Redistributions of source code must retain the above | |
17 | * copyright notice, this list of conditions and the following | |
18 | * disclaimer. | |
19 | * | |
20 | * - Redistributions in binary form must reproduce the above | |
21 | * copyright notice, this list of conditions and the following | |
22 | * disclaimer in the documentation and/or other materials | |
23 | * provided with the distribution. | |
24 | * | |
25 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | |
26 | * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | |
27 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | |
28 | * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS | |
29 | * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN | |
30 | * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | |
31 | * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | |
32 | * SOFTWARE. | |
eb8ffbfe RD |
33 | */ |
34 | ||
35 | #include <linux/mm.h> | |
36 | #include <linux/dma-mapping.h> | |
e8edc6e0 | 37 | #include <linux/sched.h> |
c8d8beea | 38 | #include <linux/hugetlb.h> |
cb9fbc5c | 39 | #include <linux/dma-attrs.h> |
eb8ffbfe RD |
40 | |
41 | #include "uverbs.h" | |
42 | ||
92ddc447 DB |
43 | #define IB_UMEM_MAX_PAGE_CHUNK \ |
44 | ((PAGE_SIZE - offsetof(struct ib_umem_chunk, page_list)) / \ | |
45 | ((void *) &((struct ib_umem_chunk *) 0)->page_list[1] - \ | |
46 | (void *) &((struct ib_umem_chunk *) 0)->page_list[0])) | |
47 | ||
eb8ffbfe RD |
48 | static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int dirty) |
49 | { | |
50 | struct ib_umem_chunk *chunk, *tmp; | |
51 | int i; | |
52 | ||
53 | list_for_each_entry_safe(chunk, tmp, &umem->chunk_list, list) { | |
1527106f RC |
54 | ib_dma_unmap_sg(dev, chunk->page_list, |
55 | chunk->nents, DMA_BIDIRECTIONAL); | |
eb8ffbfe | 56 | for (i = 0; i < chunk->nents; ++i) { |
45711f1a JA |
57 | struct page *page = sg_page(&chunk->page_list[i]); |
58 | ||
eb8ffbfe | 59 | if (umem->writable && dirty) |
45711f1a JA |
60 | set_page_dirty_lock(page); |
61 | put_page(page); | |
eb8ffbfe RD |
62 | } |
63 | ||
64 | kfree(chunk); | |
65 | } | |
66 | } | |
67 | ||
f7c6a7b5 RD |
68 | /** |
69 | * ib_umem_get - Pin and DMA map userspace memory. | |
70 | * @context: userspace context to pin memory for | |
71 | * @addr: userspace virtual address to start at | |
72 | * @size: length of region to pin | |
73 | * @access: IB_ACCESS_xxx flags for memory being pinned | |
cb9fbc5c | 74 | * @dmasync: flush in-flight DMA when the memory region is written |
f7c6a7b5 RD |
75 | */ |
76 | struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr, | |
cb9fbc5c | 77 | size_t size, int access, int dmasync) |
eb8ffbfe | 78 | { |
f7c6a7b5 | 79 | struct ib_umem *umem; |
eb8ffbfe | 80 | struct page **page_list; |
c8d8beea | 81 | struct vm_area_struct **vma_list; |
eb8ffbfe RD |
82 | struct ib_umem_chunk *chunk; |
83 | unsigned long locked; | |
84 | unsigned long lock_limit; | |
85 | unsigned long cur_base; | |
86 | unsigned long npages; | |
f7c6a7b5 | 87 | int ret; |
eb8ffbfe RD |
88 | int off; |
89 | int i; | |
cb9fbc5c AK |
90 | DEFINE_DMA_ATTRS(attrs); |
91 | ||
92 | if (dmasync) | |
93 | dma_set_attr(DMA_ATTR_WRITE_BARRIER, &attrs); | |
eb8ffbfe RD |
94 | |
95 | if (!can_do_mlock()) | |
f7c6a7b5 | 96 | return ERR_PTR(-EPERM); |
eb8ffbfe | 97 | |
f7c6a7b5 RD |
98 | umem = kmalloc(sizeof *umem, GFP_KERNEL); |
99 | if (!umem) | |
100 | return ERR_PTR(-ENOMEM); | |
eb8ffbfe | 101 | |
f7c6a7b5 RD |
102 | umem->context = context; |
103 | umem->length = size; | |
104 | umem->offset = addr & ~PAGE_MASK; | |
105 | umem->page_size = PAGE_SIZE; | |
106 | /* | |
107 | * We ask for writable memory if any access flags other than | |
108 | * "remote read" are set. "Local write" and "remote write" | |
109 | * obviously require write access. "Remote atomic" can do | |
110 | * things like fetch and add, which will modify memory, and | |
111 | * "MW bind" can change permissions by binding a window. | |
112 | */ | |
113 | umem->writable = !!(access & ~IB_ACCESS_REMOTE_READ); | |
eb8ffbfe | 114 | |
c8d8beea JF |
115 | /* We assume the memory is from hugetlb until proved otherwise */ |
116 | umem->hugetlb = 1; | |
117 | ||
f7c6a7b5 RD |
118 | INIT_LIST_HEAD(&umem->chunk_list); |
119 | ||
120 | page_list = (struct page **) __get_free_page(GFP_KERNEL); | |
121 | if (!page_list) { | |
122 | kfree(umem); | |
123 | return ERR_PTR(-ENOMEM); | |
124 | } | |
eb8ffbfe | 125 | |
c8d8beea JF |
126 | /* |
127 | * if we can't alloc the vma_list, it's not so bad; | |
128 | * just assume the memory is not hugetlb memory | |
129 | */ | |
130 | vma_list = (struct vm_area_struct **) __get_free_page(GFP_KERNEL); | |
131 | if (!vma_list) | |
132 | umem->hugetlb = 0; | |
133 | ||
f7c6a7b5 | 134 | npages = PAGE_ALIGN(size + umem->offset) >> PAGE_SHIFT; |
eb8ffbfe RD |
135 | |
136 | down_write(¤t->mm->mmap_sem); | |
137 | ||
138 | locked = npages + current->mm->locked_vm; | |
ccbe9f0b | 139 | lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; |
eb8ffbfe RD |
140 | |
141 | if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) { | |
142 | ret = -ENOMEM; | |
143 | goto out; | |
144 | } | |
145 | ||
f7c6a7b5 | 146 | cur_base = addr & PAGE_MASK; |
eb8ffbfe | 147 | |
1d3f4b90 | 148 | ret = 0; |
eb8ffbfe RD |
149 | while (npages) { |
150 | ret = get_user_pages(current, current->mm, cur_base, | |
8079ffa0 | 151 | min_t(unsigned long, npages, |
eb8ffbfe | 152 | PAGE_SIZE / sizeof (struct page *)), |
c8d8beea | 153 | 1, !umem->writable, page_list, vma_list); |
eb8ffbfe RD |
154 | |
155 | if (ret < 0) | |
156 | goto out; | |
157 | ||
158 | cur_base += ret * PAGE_SIZE; | |
159 | npages -= ret; | |
160 | ||
161 | off = 0; | |
162 | ||
163 | while (ret) { | |
164 | chunk = kmalloc(sizeof *chunk + sizeof (struct scatterlist) * | |
165 | min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK), | |
166 | GFP_KERNEL); | |
167 | if (!chunk) { | |
168 | ret = -ENOMEM; | |
169 | goto out; | |
170 | } | |
171 | ||
172 | chunk->nents = min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK); | |
45711f1a | 173 | sg_init_table(chunk->page_list, chunk->nents); |
eb8ffbfe | 174 | for (i = 0; i < chunk->nents; ++i) { |
c8d8beea JF |
175 | if (vma_list && |
176 | !is_vm_hugetlb_page(vma_list[i + off])) | |
177 | umem->hugetlb = 0; | |
642f1490 | 178 | sg_set_page(&chunk->page_list[i], page_list[i + off], PAGE_SIZE, 0); |
eb8ffbfe RD |
179 | } |
180 | ||
cb9fbc5c AK |
181 | chunk->nmap = ib_dma_map_sg_attrs(context->device, |
182 | &chunk->page_list[0], | |
183 | chunk->nents, | |
184 | DMA_BIDIRECTIONAL, | |
185 | &attrs); | |
eb8ffbfe RD |
186 | if (chunk->nmap <= 0) { |
187 | for (i = 0; i < chunk->nents; ++i) | |
45711f1a | 188 | put_page(sg_page(&chunk->page_list[i])); |
eb8ffbfe RD |
189 | kfree(chunk); |
190 | ||
191 | ret = -ENOMEM; | |
192 | goto out; | |
193 | } | |
194 | ||
195 | ret -= chunk->nents; | |
196 | off += chunk->nents; | |
f7c6a7b5 | 197 | list_add_tail(&chunk->list, &umem->chunk_list); |
eb8ffbfe RD |
198 | } |
199 | ||
200 | ret = 0; | |
201 | } | |
202 | ||
203 | out: | |
f7c6a7b5 RD |
204 | if (ret < 0) { |
205 | __ib_umem_release(context->device, umem, 0); | |
206 | kfree(umem); | |
207 | } else | |
eb8ffbfe RD |
208 | current->mm->locked_vm = locked; |
209 | ||
210 | up_write(¤t->mm->mmap_sem); | |
c8d8beea JF |
211 | if (vma_list) |
212 | free_page((unsigned long) vma_list); | |
eb8ffbfe RD |
213 | free_page((unsigned long) page_list); |
214 | ||
f7c6a7b5 | 215 | return ret < 0 ? ERR_PTR(ret) : umem; |
eb8ffbfe | 216 | } |
f7c6a7b5 | 217 | EXPORT_SYMBOL(ib_umem_get); |
eb8ffbfe | 218 | |
1bf66a30 | 219 | static void ib_umem_account(struct work_struct *work) |
eb8ffbfe | 220 | { |
1bf66a30 RD |
221 | struct ib_umem *umem = container_of(work, struct ib_umem, work); |
222 | ||
223 | down_write(&umem->mm->mmap_sem); | |
224 | umem->mm->locked_vm -= umem->diff; | |
225 | up_write(&umem->mm->mmap_sem); | |
226 | mmput(umem->mm); | |
227 | kfree(umem); | |
eb8ffbfe RD |
228 | } |
229 | ||
f7c6a7b5 RD |
230 | /** |
231 | * ib_umem_release - release memory pinned with ib_umem_get | |
232 | * @umem: umem struct to release | |
233 | */ | |
234 | void ib_umem_release(struct ib_umem *umem) | |
eb8ffbfe | 235 | { |
f7c6a7b5 | 236 | struct ib_ucontext *context = umem->context; |
eb8ffbfe | 237 | struct mm_struct *mm; |
f7c6a7b5 | 238 | unsigned long diff; |
eb8ffbfe | 239 | |
f7c6a7b5 | 240 | __ib_umem_release(umem->context->device, umem, 1); |
eb8ffbfe RD |
241 | |
242 | mm = get_task_mm(current); | |
7b82cd8e EC |
243 | if (!mm) { |
244 | kfree(umem); | |
eb8ffbfe | 245 | return; |
7b82cd8e | 246 | } |
eb8ffbfe | 247 | |
f7c6a7b5 | 248 | diff = PAGE_ALIGN(umem->length + umem->offset) >> PAGE_SHIFT; |
f7c6a7b5 | 249 | |
eb8ffbfe RD |
250 | /* |
251 | * We may be called with the mm's mmap_sem already held. This | |
252 | * can happen when a userspace munmap() is the call that drops | |
253 | * the last reference to our file and calls our release | |
254 | * method. If there are memory regions to destroy, we'll end | |
f7c6a7b5 RD |
255 | * up here and not be able to take the mmap_sem. In that case |
256 | * we defer the vm_locked accounting to the system workqueue. | |
eb8ffbfe | 257 | */ |
24bce508 RD |
258 | if (context->closing) { |
259 | if (!down_write_trylock(&mm->mmap_sem)) { | |
260 | INIT_WORK(&umem->work, ib_umem_account); | |
261 | umem->mm = mm; | |
262 | umem->diff = diff; | |
263 | ||
264 | schedule_work(&umem->work); | |
265 | return; | |
266 | } | |
f7c6a7b5 RD |
267 | } else |
268 | down_write(&mm->mmap_sem); | |
269 | ||
270 | current->mm->locked_vm -= diff; | |
271 | up_write(&mm->mmap_sem); | |
272 | mmput(mm); | |
1bf66a30 | 273 | kfree(umem); |
f7c6a7b5 RD |
274 | } |
275 | EXPORT_SYMBOL(ib_umem_release); | |
276 | ||
277 | int ib_umem_page_count(struct ib_umem *umem) | |
278 | { | |
279 | struct ib_umem_chunk *chunk; | |
280 | int shift; | |
281 | int i; | |
282 | int n; | |
283 | ||
284 | shift = ilog2(umem->page_size); | |
eb8ffbfe | 285 | |
f7c6a7b5 RD |
286 | n = 0; |
287 | list_for_each_entry(chunk, &umem->chunk_list, list) | |
288 | for (i = 0; i < chunk->nmap; ++i) | |
289 | n += sg_dma_len(&chunk->page_list[i]) >> shift; | |
eb8ffbfe | 290 | |
f7c6a7b5 | 291 | return n; |
eb8ffbfe | 292 | } |
f7c6a7b5 | 293 | EXPORT_SYMBOL(ib_umem_page_count); |