1 /*
2 * Copyright(c) 2016 Intel Corporation.
3 *
4 * This file is provided under a dual BSD/GPLv2 license. When using or
5 * redistributing this file, you may do so under either license.
6 *
7 * GPL LICENSE SUMMARY
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of version 2 of the GNU General Public License as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * BSD LICENSE
19 *
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
22 * are met:
23 *
24 * - Redistributions of source code must retain the above copyright
25 * notice, this list of conditions and the following disclaimer.
26 * - Redistributions in binary form must reproduce the above copyright
27 * notice, this list of conditions and the following disclaimer in
28 * the documentation and/or other materials provided with the
29 * distribution.
30 * - Neither the name of Intel Corporation nor the names of its
31 * contributors may be used to endorse or promote products derived
32 * from this software without specific prior written permission.
33 *
34 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45 *
46 */
47
48 #include <linux/slab.h>
49 #include <linux/vmalloc.h>
50 #include <linux/mm.h>
51 #include <asm/pgtable.h>
52 #include <rdma/uverbs_ioctl.h>
53 #include "mmap.h"
54
55 /**
56 * rvt_mmap_init - init link list and lock for mem map
57 * @rdi: rvt dev struct
58 */
59 void rvt_mmap_init(struct rvt_dev_info *rdi)
60 {
61 INIT_LIST_HEAD(&rdi->pending_mmaps);
62 spin_lock_init(&rdi->pending_lock);
63 rdi->mmap_offset = PAGE_SIZE;
64 spin_lock_init(&rdi->mmap_offset_lock);
65 }
66
67 /**
68 * rvt_release_mmap_info - free mmap info structure
69 * @ref: a pointer to the kref within struct rvt_mmap_info
70 */
71 void rvt_release_mmap_info(struct kref *ref)
72 {
73 struct rvt_mmap_info *ip =
74 container_of(ref, struct rvt_mmap_info, ref);
75 struct rvt_dev_info *rdi = ib_to_rvt(ip->context->device);
76
77 spin_lock_irq(&rdi->pending_lock);
78 list_del(&ip->pending_mmaps);
79 spin_unlock_irq(&rdi->pending_lock);
80
81 vfree(ip->obj);
82 kfree(ip);
83 }
84
85 static void rvt_vma_open(struct vm_area_struct *vma)
86 {
87 struct rvt_mmap_info *ip = vma->vm_private_data;
88
89 kref_get(&ip->ref);
90 }
91
92 static void rvt_vma_close(struct vm_area_struct *vma)
93 {
94 struct rvt_mmap_info *ip = vma->vm_private_data;
95
96 kref_put(&ip->ref, rvt_release_mmap_info);
97 }
98
99 static const struct vm_operations_struct rvt_vm_ops = {
100 .open = rvt_vma_open,
101 .close = rvt_vma_close,
102 };
103
104 /**
105 * rvt_mmap - create a new mmap region
106 * @context: the IB user context of the process making the mmap() call
107 * @vma: the VMA to be initialized
108 *
109 * Return: zero if the mmap is OK. Otherwise, return an errno.
110 */
111 int rvt_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
112 {
113 struct rvt_dev_info *rdi = ib_to_rvt(context->device);
114 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
115 unsigned long size = vma->vm_end - vma->vm_start;
116 struct rvt_mmap_info *ip, *pp;
117 int ret = -EINVAL;
118
119 /*
120 * Search the device's list of objects waiting for a mmap call.
121 * Normally, this list is very short since a call to create a
122 * CQ, QP, or SRQ is soon followed by a call to mmap().
123 */
124 spin_lock_irq(&rdi->pending_lock);
125 list_for_each_entry_safe(ip, pp, &rdi->pending_mmaps,
126 pending_mmaps) {
127 /* Only the creator is allowed to mmap the object */
128 if (context != ip->context || (__u64)offset != ip->offset)
129 continue;
130 /* Don't allow a mmap larger than the object. */
131 if (size > ip->size)
132 break;
133
134 list_del_init(&ip->pending_mmaps);
135 spin_unlock_irq(&rdi->pending_lock);
136
137 ret = remap_vmalloc_range(vma, ip->obj, 0);
138 if (ret)
139 goto done;
140 vma->vm_ops = &rvt_vm_ops;
141 vma->vm_private_data = ip;
142 rvt_vma_open(vma);
143 goto done;
144 }
145 spin_unlock_irq(&rdi->pending_lock);
146 done:
147 return ret;
148 }
149
150 /**
151 * rvt_create_mmap_info - allocate information for hfi1_mmap
152 * @rdi: rvt dev struct
153 * @size: size in bytes to map
154 * @udata: user data (must be valid!)
155 * @obj: opaque pointer to a cq, wq etc
156 *
157 * Return: rvt_mmap struct on success, ERR_PTR on failure
158 */
159 struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, u32 size,
160 struct ib_udata *udata, void *obj)
161 {
162 struct rvt_mmap_info *ip;
163
164 if (!udata)
165 return ERR_PTR(-EINVAL);
166
167 ip = kmalloc_node(sizeof(*ip), GFP_KERNEL, rdi->dparms.node);
168 if (!ip)
169 return ERR_PTR(-ENOMEM);
170
171 size = PAGE_ALIGN(size);
172
173 spin_lock_irq(&rdi->mmap_offset_lock);
174 if (rdi->mmap_offset == 0)
175 rdi->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA);
176 ip->offset = rdi->mmap_offset;
177 rdi->mmap_offset += ALIGN(size, SHMLBA);
178 spin_unlock_irq(&rdi->mmap_offset_lock);
179
180 INIT_LIST_HEAD(&ip->pending_mmaps);
181 ip->size = size;
182 ip->context =
183 container_of(udata, struct uverbs_attr_bundle, driver_udata)
184 ->context;
185 ip->obj = obj;
186 kref_init(&ip->ref);
187
188 return ip;
189 }
190
191 /**
192 * rvt_update_mmap_info - update a mem map
193 * @rdi: rvt dev struct
194 * @ip: mmap info pointer
195 * @size: size to grow by
196 * @obj: opaque pointer to cq, wq, etc.
197 */
198 void rvt_update_mmap_info(struct rvt_dev_info *rdi, struct rvt_mmap_info *ip,
199 u32 size, void *obj)
200 {
201 size = PAGE_ALIGN(size);
202
203 spin_lock_irq(&rdi->mmap_offset_lock);
204 if (rdi->mmap_offset == 0)
205 rdi->mmap_offset = PAGE_SIZE;
206 ip->offset = rdi->mmap_offset;
207 rdi->mmap_offset += size;
208 spin_unlock_irq(&rdi->mmap_offset_lock);
209
210 ip->size = size;
211 ip->obj = obj;
212 }