1 /*
2 * Copyright (c) 2006, 2007 QLogic Corporation. 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 <linux/module.h>
34 #include <linux/vmalloc.h>
35 #include <linux/mm.h>
36 #include <linux/errno.h>
37 #include <asm/pgtable.h>
38
39 #include "ipath_verbs.h"
40
41 /**
42 * ipath_release_mmap_info - free mmap info structure
43 * @ref: a pointer to the kref within struct ipath_mmap_info
44 */
ipath_release_mmap_info(struct kref * ref)45 void ipath_release_mmap_info(struct kref *ref)
46 {
47 struct ipath_mmap_info *ip =
48 container_of(ref, struct ipath_mmap_info, ref);
49 struct ipath_ibdev *dev = to_idev(ip->context->device);
50
51 spin_lock_irq(&dev->pending_lock);
52 list_del(&ip->pending_mmaps);
53 spin_unlock_irq(&dev->pending_lock);
54
55 vfree(ip->obj);
56 kfree(ip);
57 }
58
59 /*
60 * open and close keep track of how many times the CQ is mapped,
61 * to avoid releasing it.
62 */
ipath_vma_open(struct vm_area_struct * vma)63 static void ipath_vma_open(struct vm_area_struct *vma)
64 {
65 struct ipath_mmap_info *ip = vma->vm_private_data;
66
67 kref_get(&ip->ref);
68 }
69
ipath_vma_close(struct vm_area_struct * vma)70 static void ipath_vma_close(struct vm_area_struct *vma)
71 {
72 struct ipath_mmap_info *ip = vma->vm_private_data;
73
74 kref_put(&ip->ref, ipath_release_mmap_info);
75 }
76
77 static struct vm_operations_struct ipath_vm_ops = {
78 .open = ipath_vma_open,
79 .close = ipath_vma_close,
80 };
81
82 /**
83 * ipath_mmap - create a new mmap region
84 * @context: the IB user context of the process making the mmap() call
85 * @vma: the VMA to be initialized
86 * Return zero if the mmap is OK. Otherwise, return an errno.
87 */
ipath_mmap(struct ib_ucontext * context,struct vm_area_struct * vma)88 int ipath_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
89 {
90 struct ipath_ibdev *dev = to_idev(context->device);
91 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
92 unsigned long size = vma->vm_end - vma->vm_start;
93 struct ipath_mmap_info *ip, *pp;
94 int ret = -EINVAL;
95
96 /*
97 * Search the device's list of objects waiting for a mmap call.
98 * Normally, this list is very short since a call to create a
99 * CQ, QP, or SRQ is soon followed by a call to mmap().
100 */
101 spin_lock_irq(&dev->pending_lock);
102 list_for_each_entry_safe(ip, pp, &dev->pending_mmaps,
103 pending_mmaps) {
104 /* Only the creator is allowed to mmap the object */
105 if (context != ip->context || (__u64) offset != ip->offset)
106 continue;
107 /* Don't allow a mmap larger than the object. */
108 if (size > ip->size)
109 break;
110
111 list_del_init(&ip->pending_mmaps);
112 spin_unlock_irq(&dev->pending_lock);
113
114 ret = remap_vmalloc_range(vma, ip->obj, 0);
115 if (ret)
116 goto done;
117 vma->vm_ops = &ipath_vm_ops;
118 vma->vm_private_data = ip;
119 ipath_vma_open(vma);
120 goto done;
121 }
122 spin_unlock_irq(&dev->pending_lock);
123 done:
124 return ret;
125 }
126
127 /*
128 * Allocate information for ipath_mmap
129 */
ipath_create_mmap_info(struct ipath_ibdev * dev,u32 size,struct ib_ucontext * context,void * obj)130 struct ipath_mmap_info *ipath_create_mmap_info(struct ipath_ibdev *dev,
131 u32 size,
132 struct ib_ucontext *context,
133 void *obj) {
134 struct ipath_mmap_info *ip;
135
136 ip = kmalloc(sizeof *ip, GFP_KERNEL);
137 if (!ip)
138 goto bail;
139
140 size = PAGE_ALIGN(size);
141
142 spin_lock_irq(&dev->mmap_offset_lock);
143 if (dev->mmap_offset == 0)
144 dev->mmap_offset = PAGE_SIZE;
145 ip->offset = dev->mmap_offset;
146 dev->mmap_offset += size;
147 spin_unlock_irq(&dev->mmap_offset_lock);
148
149 INIT_LIST_HEAD(&ip->pending_mmaps);
150 ip->size = size;
151 ip->context = context;
152 ip->obj = obj;
153 kref_init(&ip->ref);
154
155 bail:
156 return ip;
157 }
158
ipath_update_mmap_info(struct ipath_ibdev * dev,struct ipath_mmap_info * ip,u32 size,void * obj)159 void ipath_update_mmap_info(struct ipath_ibdev *dev,
160 struct ipath_mmap_info *ip,
161 u32 size, void *obj) {
162 size = PAGE_ALIGN(size);
163
164 spin_lock_irq(&dev->mmap_offset_lock);
165 if (dev->mmap_offset == 0)
166 dev->mmap_offset = PAGE_SIZE;
167 ip->offset = dev->mmap_offset;
168 dev->mmap_offset += size;
169 spin_unlock_irq(&dev->mmap_offset_lock);
170
171 ip->size = size;
172 ip->obj = obj;
173 }
174