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.
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:
12 * Redistribution and use in source and binary forms, with or
13 * without modification, are permitted provided that the following
16 * - Redistributions of source code must retain the above
17 * copyright notice, this list of conditions and the following
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.
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
34 * $Id: uverbs_mem.c 2743 2005-06-28 22:27:59Z roland $
38 #include <linux/dma-mapping.h>
42 struct ib_umem_account_work
{
43 struct work_struct work
;
49 static void __ib_umem_release(struct ib_device
*dev
, struct ib_umem
*umem
, int dirty
)
51 struct ib_umem_chunk
*chunk
, *tmp
;
54 list_for_each_entry_safe(chunk
, tmp
, &umem
->chunk_list
, list
) {
55 ib_dma_unmap_sg(dev
, 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
);
68 * ib_umem_get - Pin and DMA map userspace memory.
69 * @context: userspace context to pin memory for
70 * @addr: userspace virtual address to start at
71 * @size: length of region to pin
72 * @access: IB_ACCESS_xxx flags for memory being pinned
74 struct ib_umem
*ib_umem_get(struct ib_ucontext
*context
, unsigned long addr
,
75 size_t size
, int access
)
78 struct page
**page_list
;
79 struct ib_umem_chunk
*chunk
;
81 unsigned long lock_limit
;
82 unsigned long cur_base
;
89 return ERR_PTR(-EPERM
);
91 umem
= kmalloc(sizeof *umem
, GFP_KERNEL
);
93 return ERR_PTR(-ENOMEM
);
95 umem
->context
= context
;
97 umem
->offset
= addr
& ~PAGE_MASK
;
98 umem
->page_size
= PAGE_SIZE
;
100 * We ask for writable memory if any access flags other than
101 * "remote read" are set. "Local write" and "remote write"
102 * obviously require write access. "Remote atomic" can do
103 * things like fetch and add, which will modify memory, and
104 * "MW bind" can change permissions by binding a window.
106 umem
->writable
= !!(access
& ~IB_ACCESS_REMOTE_READ
);
108 INIT_LIST_HEAD(&umem
->chunk_list
);
110 page_list
= (struct page
**) __get_free_page(GFP_KERNEL
);
113 return ERR_PTR(-ENOMEM
);
116 npages
= PAGE_ALIGN(size
+ umem
->offset
) >> PAGE_SHIFT
;
118 down_write(¤t
->mm
->mmap_sem
);
120 locked
= npages
+ current
->mm
->locked_vm
;
121 lock_limit
= current
->signal
->rlim
[RLIMIT_MEMLOCK
].rlim_cur
>> PAGE_SHIFT
;
123 if ((locked
> lock_limit
) && !capable(CAP_IPC_LOCK
)) {
128 cur_base
= addr
& PAGE_MASK
;
131 ret
= get_user_pages(current
, current
->mm
, cur_base
,
133 PAGE_SIZE
/ sizeof (struct page
*)),
134 1, !umem
->writable
, page_list
, NULL
);
139 cur_base
+= ret
* PAGE_SIZE
;
145 chunk
= kmalloc(sizeof *chunk
+ sizeof (struct scatterlist
) *
146 min_t(int, ret
, IB_UMEM_MAX_PAGE_CHUNK
),
153 chunk
->nents
= min_t(int, ret
, IB_UMEM_MAX_PAGE_CHUNK
);
154 for (i
= 0; i
< chunk
->nents
; ++i
) {
155 chunk
->page_list
[i
].page
= page_list
[i
+ off
];
156 chunk
->page_list
[i
].offset
= 0;
157 chunk
->page_list
[i
].length
= PAGE_SIZE
;
160 chunk
->nmap
= ib_dma_map_sg(context
->device
,
161 &chunk
->page_list
[0],
164 if (chunk
->nmap
<= 0) {
165 for (i
= 0; i
< chunk
->nents
; ++i
)
166 put_page(chunk
->page_list
[i
].page
);
175 list_add_tail(&chunk
->list
, &umem
->chunk_list
);
183 __ib_umem_release(context
->device
, umem
, 0);
186 current
->mm
->locked_vm
= locked
;
188 up_write(¤t
->mm
->mmap_sem
);
189 free_page((unsigned long) page_list
);
191 return ret
< 0 ? ERR_PTR(ret
) : umem
;
193 EXPORT_SYMBOL(ib_umem_get
);
195 static void ib_umem_account(struct work_struct
*_work
)
197 struct ib_umem_account_work
*work
=
198 container_of(_work
, struct ib_umem_account_work
, work
);
200 down_write(&work
->mm
->mmap_sem
);
201 work
->mm
->locked_vm
-= work
->diff
;
202 up_write(&work
->mm
->mmap_sem
);
208 * ib_umem_release - release memory pinned with ib_umem_get
209 * @umem: umem struct to release
211 void ib_umem_release(struct ib_umem
*umem
)
213 struct ib_umem_account_work
*work
;
214 struct ib_ucontext
*context
= umem
->context
;
215 struct mm_struct
*mm
;
218 __ib_umem_release(umem
->context
->device
, umem
, 1);
220 mm
= get_task_mm(current
);
224 diff
= PAGE_ALIGN(umem
->length
+ umem
->offset
) >> PAGE_SHIFT
;
228 * We may be called with the mm's mmap_sem already held. This
229 * can happen when a userspace munmap() is the call that drops
230 * the last reference to our file and calls our release
231 * method. If there are memory regions to destroy, we'll end
232 * up here and not be able to take the mmap_sem. In that case
233 * we defer the vm_locked accounting to the system workqueue.
235 if (context
->closing
&& !down_write_trylock(&mm
->mmap_sem
)) {
236 work
= kmalloc(sizeof *work
, GFP_KERNEL
);
242 INIT_WORK(&work
->work
, ib_umem_account
);
246 schedule_work(&work
->work
);
249 down_write(&mm
->mmap_sem
);
251 current
->mm
->locked_vm
-= diff
;
252 up_write(&mm
->mmap_sem
);
255 EXPORT_SYMBOL(ib_umem_release
);
257 int ib_umem_page_count(struct ib_umem
*umem
)
259 struct ib_umem_chunk
*chunk
;
264 shift
= ilog2(umem
->page_size
);
267 list_for_each_entry(chunk
, &umem
->chunk_list
, list
)
268 for (i
= 0; i
< chunk
->nmap
; ++i
)
269 n
+= sg_dma_len(&chunk
->page_list
[i
]) >> shift
;
273 EXPORT_SYMBOL(ib_umem_page_count
);