1 | // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause |
2 | /* |
3 | * Copyright(c) 2016 Intel Corporation. |
4 | */ |
5 | |
6 | #include <linux/slab.h> |
7 | #include <linux/vmalloc.h> |
8 | #include <linux/mm.h> |
9 | #include <rdma/uverbs_ioctl.h> |
10 | #include "mmap.h" |
11 | |
12 | /** |
13 | * rvt_mmap_init - init link list and lock for mem map |
14 | * @rdi: rvt dev struct |
15 | */ |
16 | void rvt_mmap_init(struct rvt_dev_info *rdi) |
17 | { |
18 | INIT_LIST_HEAD(list: &rdi->pending_mmaps); |
19 | spin_lock_init(&rdi->pending_lock); |
20 | rdi->mmap_offset = PAGE_SIZE; |
21 | spin_lock_init(&rdi->mmap_offset_lock); |
22 | } |
23 | |
24 | /** |
25 | * rvt_release_mmap_info - free mmap info structure |
26 | * @ref: a pointer to the kref within struct rvt_mmap_info |
27 | */ |
28 | void rvt_release_mmap_info(struct kref *ref) |
29 | { |
30 | struct rvt_mmap_info *ip = |
31 | container_of(ref, struct rvt_mmap_info, ref); |
32 | struct rvt_dev_info *rdi = ib_to_rvt(ibdev: ip->context->device); |
33 | |
34 | spin_lock_irq(lock: &rdi->pending_lock); |
35 | list_del(entry: &ip->pending_mmaps); |
36 | spin_unlock_irq(lock: &rdi->pending_lock); |
37 | |
38 | vfree(addr: ip->obj); |
39 | kfree(objp: ip); |
40 | } |
41 | |
42 | static void rvt_vma_open(struct vm_area_struct *vma) |
43 | { |
44 | struct rvt_mmap_info *ip = vma->vm_private_data; |
45 | |
46 | kref_get(kref: &ip->ref); |
47 | } |
48 | |
49 | static void rvt_vma_close(struct vm_area_struct *vma) |
50 | { |
51 | struct rvt_mmap_info *ip = vma->vm_private_data; |
52 | |
53 | kref_put(kref: &ip->ref, release: rvt_release_mmap_info); |
54 | } |
55 | |
56 | static const struct vm_operations_struct rvt_vm_ops = { |
57 | .open = rvt_vma_open, |
58 | .close = rvt_vma_close, |
59 | }; |
60 | |
61 | /** |
62 | * rvt_mmap - create a new mmap region |
63 | * @context: the IB user context of the process making the mmap() call |
64 | * @vma: the VMA to be initialized |
65 | * |
66 | * Return: zero if the mmap is OK. Otherwise, return an errno. |
67 | */ |
68 | int rvt_mmap(struct ib_ucontext *context, struct vm_area_struct *vma) |
69 | { |
70 | struct rvt_dev_info *rdi = ib_to_rvt(ibdev: context->device); |
71 | unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; |
72 | unsigned long size = vma->vm_end - vma->vm_start; |
73 | struct rvt_mmap_info *ip, *pp; |
74 | int ret = -EINVAL; |
75 | |
76 | /* |
77 | * Search the device's list of objects waiting for a mmap call. |
78 | * Normally, this list is very short since a call to create a |
79 | * CQ, QP, or SRQ is soon followed by a call to mmap(). |
80 | */ |
81 | spin_lock_irq(lock: &rdi->pending_lock); |
82 | list_for_each_entry_safe(ip, pp, &rdi->pending_mmaps, |
83 | pending_mmaps) { |
84 | /* Only the creator is allowed to mmap the object */ |
85 | if (context != ip->context || (__u64)offset != ip->offset) |
86 | continue; |
87 | /* Don't allow a mmap larger than the object. */ |
88 | if (size > ip->size) |
89 | break; |
90 | |
91 | list_del_init(entry: &ip->pending_mmaps); |
92 | spin_unlock_irq(lock: &rdi->pending_lock); |
93 | |
94 | ret = remap_vmalloc_range(vma, addr: ip->obj, pgoff: 0); |
95 | if (ret) |
96 | goto done; |
97 | vma->vm_ops = &rvt_vm_ops; |
98 | vma->vm_private_data = ip; |
99 | rvt_vma_open(vma); |
100 | goto done; |
101 | } |
102 | spin_unlock_irq(lock: &rdi->pending_lock); |
103 | done: |
104 | return ret; |
105 | } |
106 | |
107 | /** |
108 | * rvt_create_mmap_info - allocate information for hfi1_mmap |
109 | * @rdi: rvt dev struct |
110 | * @size: size in bytes to map |
111 | * @udata: user data (must be valid!) |
112 | * @obj: opaque pointer to a cq, wq etc |
113 | * |
114 | * Return: rvt_mmap struct on success, ERR_PTR on failure |
115 | */ |
116 | struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, u32 size, |
117 | struct ib_udata *udata, void *obj) |
118 | { |
119 | struct rvt_mmap_info *ip; |
120 | |
121 | if (!udata) |
122 | return ERR_PTR(error: -EINVAL); |
123 | |
124 | ip = kmalloc_node(size: sizeof(*ip), GFP_KERNEL, node: rdi->dparms.node); |
125 | if (!ip) |
126 | return ERR_PTR(error: -ENOMEM); |
127 | |
128 | size = PAGE_ALIGN(size); |
129 | |
130 | spin_lock_irq(lock: &rdi->mmap_offset_lock); |
131 | if (rdi->mmap_offset == 0) |
132 | rdi->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA); |
133 | ip->offset = rdi->mmap_offset; |
134 | rdi->mmap_offset += ALIGN(size, SHMLBA); |
135 | spin_unlock_irq(lock: &rdi->mmap_offset_lock); |
136 | |
137 | INIT_LIST_HEAD(list: &ip->pending_mmaps); |
138 | ip->size = size; |
139 | ip->context = |
140 | container_of(udata, struct uverbs_attr_bundle, driver_udata) |
141 | ->context; |
142 | ip->obj = obj; |
143 | kref_init(kref: &ip->ref); |
144 | |
145 | return ip; |
146 | } |
147 | |
148 | /** |
149 | * rvt_update_mmap_info - update a mem map |
150 | * @rdi: rvt dev struct |
151 | * @ip: mmap info pointer |
152 | * @size: size to grow by |
153 | * @obj: opaque pointer to cq, wq, etc. |
154 | */ |
155 | void rvt_update_mmap_info(struct rvt_dev_info *rdi, struct rvt_mmap_info *ip, |
156 | u32 size, void *obj) |
157 | { |
158 | size = PAGE_ALIGN(size); |
159 | |
160 | spin_lock_irq(lock: &rdi->mmap_offset_lock); |
161 | if (rdi->mmap_offset == 0) |
162 | rdi->mmap_offset = PAGE_SIZE; |
163 | ip->offset = rdi->mmap_offset; |
164 | rdi->mmap_offset += size; |
165 | spin_unlock_irq(lock: &rdi->mmap_offset_lock); |
166 | |
167 | ip->size = size; |
168 | ip->obj = obj; |
169 | } |
170 | |