WorkStruct: make allyesconfig
[linux-3.10.git] / drivers / infiniband / core / uverbs_mem.c
1 /*
2  * Copyright (c) 2005 Topspin Communications.  All rights reserved.
3  * Copyright (c) 2005 Cisco Systems.  All rights reserved.
4  * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
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.
33  *
34  * $Id: uverbs_mem.c 2743 2005-06-28 22:27:59Z roland $
35  */
36
37 #include <linux/mm.h>
38 #include <linux/dma-mapping.h>
39
40 #include "uverbs.h"
41
42 struct ib_umem_account_work {
43         struct work_struct work;
44         struct mm_struct  *mm;
45         unsigned long      diff;
46 };
47
48
49 static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int dirty)
50 {
51         struct ib_umem_chunk *chunk, *tmp;
52         int i;
53
54         list_for_each_entry_safe(chunk, tmp, &umem->chunk_list, list) {
55                 dma_unmap_sg(dev->dma_device, chunk->page_list,
56                              chunk->nents, DMA_BIDIRECTIONAL);
57                 for (i = 0; i < chunk->nents; ++i) {
58                         if (umem->writable && dirty)
59                                 set_page_dirty_lock(chunk->page_list[i].page);
60                         put_page(chunk->page_list[i].page);
61                 }
62
63                 kfree(chunk);
64         }
65 }
66
67 int ib_umem_get(struct ib_device *dev, struct ib_umem *mem,
68                 void *addr, size_t size, int write)
69 {
70         struct page **page_list;
71         struct ib_umem_chunk *chunk;
72         unsigned long locked;
73         unsigned long lock_limit;
74         unsigned long cur_base;
75         unsigned long npages;
76         int ret = 0;
77         int off;
78         int i;
79
80         if (!can_do_mlock())
81                 return -EPERM;
82
83         page_list = (struct page **) __get_free_page(GFP_KERNEL);
84         if (!page_list)
85                 return -ENOMEM;
86
87         mem->user_base = (unsigned long) addr;
88         mem->length    = size;
89         mem->offset    = (unsigned long) addr & ~PAGE_MASK;
90         mem->page_size = PAGE_SIZE;
91         mem->writable  = write;
92
93         INIT_LIST_HEAD(&mem->chunk_list);
94
95         npages = PAGE_ALIGN(size + mem->offset) >> PAGE_SHIFT;
96
97         down_write(&current->mm->mmap_sem);
98
99         locked     = npages + current->mm->locked_vm;
100         lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
101
102         if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
103                 ret = -ENOMEM;
104                 goto out;
105         }
106
107         cur_base = (unsigned long) addr & PAGE_MASK;
108
109         while (npages) {
110                 ret = get_user_pages(current, current->mm, cur_base,
111                                      min_t(int, npages,
112                                            PAGE_SIZE / sizeof (struct page *)),
113                                      1, !write, page_list, NULL);
114
115                 if (ret < 0)
116                         goto out;
117
118                 cur_base += ret * PAGE_SIZE;
119                 npages   -= ret;
120
121                 off = 0;
122
123                 while (ret) {
124                         chunk = kmalloc(sizeof *chunk + sizeof (struct scatterlist) *
125                                         min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK),
126                                         GFP_KERNEL);
127                         if (!chunk) {
128                                 ret = -ENOMEM;
129                                 goto out;
130                         }
131
132                         chunk->nents = min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK);
133                         for (i = 0; i < chunk->nents; ++i) {
134                                 chunk->page_list[i].page   = page_list[i + off];
135                                 chunk->page_list[i].offset = 0;
136                                 chunk->page_list[i].length = PAGE_SIZE;
137                         }
138
139                         chunk->nmap = dma_map_sg(dev->dma_device,
140                                                  &chunk->page_list[0],
141                                                  chunk->nents,
142                                                  DMA_BIDIRECTIONAL);
143                         if (chunk->nmap <= 0) {
144                                 for (i = 0; i < chunk->nents; ++i)
145                                         put_page(chunk->page_list[i].page);
146                                 kfree(chunk);
147
148                                 ret = -ENOMEM;
149                                 goto out;
150                         }
151
152                         ret -= chunk->nents;
153                         off += chunk->nents;
154                         list_add_tail(&chunk->list, &mem->chunk_list);
155                 }
156
157                 ret = 0;
158         }
159
160 out:
161         if (ret < 0)
162                 __ib_umem_release(dev, mem, 0);
163         else
164                 current->mm->locked_vm = locked;
165
166         up_write(&current->mm->mmap_sem);
167         free_page((unsigned long) page_list);
168
169         return ret;
170 }
171
172 void ib_umem_release(struct ib_device *dev, struct ib_umem *umem)
173 {
174         __ib_umem_release(dev, umem, 1);
175
176         down_write(&current->mm->mmap_sem);
177         current->mm->locked_vm -=
178                 PAGE_ALIGN(umem->length + umem->offset) >> PAGE_SHIFT;
179         up_write(&current->mm->mmap_sem);
180 }
181
182 static void ib_umem_account(struct work_struct *_work)
183 {
184         struct ib_umem_account_work *work =
185                 container_of(_work, struct ib_umem_account_work, work);
186
187         down_write(&work->mm->mmap_sem);
188         work->mm->locked_vm -= work->diff;
189         up_write(&work->mm->mmap_sem);
190         mmput(work->mm);
191         kfree(work);
192 }
193
194 void ib_umem_release_on_close(struct ib_device *dev, struct ib_umem *umem)
195 {
196         struct ib_umem_account_work *work;
197         struct mm_struct *mm;
198
199         __ib_umem_release(dev, umem, 1);
200
201         mm = get_task_mm(current);
202         if (!mm)
203                 return;
204
205         /*
206          * We may be called with the mm's mmap_sem already held.  This
207          * can happen when a userspace munmap() is the call that drops
208          * the last reference to our file and calls our release
209          * method.  If there are memory regions to destroy, we'll end
210          * up here and not be able to take the mmap_sem.  Therefore we
211          * defer the vm_locked accounting to the system workqueue.
212          */
213
214         work = kmalloc(sizeof *work, GFP_KERNEL);
215         if (!work) {
216                 mmput(mm);
217                 return;
218         }
219
220         INIT_WORK(&work->work, ib_umem_account);
221         work->mm   = mm;
222         work->diff = PAGE_ALIGN(umem->length + umem->offset) >> PAGE_SHIFT;
223
224         schedule_work(&work->work);
225 }