1 /*
2 * VMware VMCI Driver
3 *
4 * Copyright (C) 2012 VMware, Inc. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation version 2 and no later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
12 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * for more details.
14 */
15
16 #include <linux/slab.h>
17 #include "vmci_handle_array.h"
18
handle_arr_calc_size(size_t capacity)19 static size_t handle_arr_calc_size(size_t capacity)
20 {
21 return sizeof(struct vmci_handle_arr) +
22 capacity * sizeof(struct vmci_handle);
23 }
24
vmci_handle_arr_create(size_t capacity)25 struct vmci_handle_arr *vmci_handle_arr_create(size_t capacity)
26 {
27 struct vmci_handle_arr *array;
28
29 if (capacity == 0)
30 capacity = VMCI_HANDLE_ARRAY_DEFAULT_SIZE;
31
32 array = kmalloc(handle_arr_calc_size(capacity), GFP_ATOMIC);
33 if (!array)
34 return NULL;
35
36 array->capacity = capacity;
37 array->size = 0;
38
39 return array;
40 }
41
vmci_handle_arr_destroy(struct vmci_handle_arr * array)42 void vmci_handle_arr_destroy(struct vmci_handle_arr *array)
43 {
44 kfree(array);
45 }
46
vmci_handle_arr_append_entry(struct vmci_handle_arr ** array_ptr,struct vmci_handle handle)47 void vmci_handle_arr_append_entry(struct vmci_handle_arr **array_ptr,
48 struct vmci_handle handle)
49 {
50 struct vmci_handle_arr *array = *array_ptr;
51
52 if (unlikely(array->size >= array->capacity)) {
53 /* reallocate. */
54 struct vmci_handle_arr *new_array;
55 size_t new_capacity = array->capacity * VMCI_ARR_CAP_MULT;
56 size_t new_size = handle_arr_calc_size(new_capacity);
57
58 new_array = krealloc(array, new_size, GFP_ATOMIC);
59 if (!new_array)
60 return;
61
62 new_array->capacity = new_capacity;
63 *array_ptr = array = new_array;
64 }
65
66 array->entries[array->size] = handle;
67 array->size++;
68 }
69
70 /*
71 * Handle that was removed, VMCI_INVALID_HANDLE if entry not found.
72 */
vmci_handle_arr_remove_entry(struct vmci_handle_arr * array,struct vmci_handle entry_handle)73 struct vmci_handle vmci_handle_arr_remove_entry(struct vmci_handle_arr *array,
74 struct vmci_handle entry_handle)
75 {
76 struct vmci_handle handle = VMCI_INVALID_HANDLE;
77 size_t i;
78
79 for (i = 0; i < array->size; i++) {
80 if (vmci_handle_is_equal(array->entries[i], entry_handle)) {
81 handle = array->entries[i];
82 array->size--;
83 array->entries[i] = array->entries[array->size];
84 array->entries[array->size] = VMCI_INVALID_HANDLE;
85 break;
86 }
87 }
88
89 return handle;
90 }
91
92 /*
93 * Handle that was removed, VMCI_INVALID_HANDLE if array was empty.
94 */
vmci_handle_arr_remove_tail(struct vmci_handle_arr * array)95 struct vmci_handle vmci_handle_arr_remove_tail(struct vmci_handle_arr *array)
96 {
97 struct vmci_handle handle = VMCI_INVALID_HANDLE;
98
99 if (array->size) {
100 array->size--;
101 handle = array->entries[array->size];
102 array->entries[array->size] = VMCI_INVALID_HANDLE;
103 }
104
105 return handle;
106 }
107
108 /*
109 * Handle at given index, VMCI_INVALID_HANDLE if invalid index.
110 */
111 struct vmci_handle
vmci_handle_arr_get_entry(const struct vmci_handle_arr * array,size_t index)112 vmci_handle_arr_get_entry(const struct vmci_handle_arr *array, size_t index)
113 {
114 if (unlikely(index >= array->size))
115 return VMCI_INVALID_HANDLE;
116
117 return array->entries[index];
118 }
119
vmci_handle_arr_has_entry(const struct vmci_handle_arr * array,struct vmci_handle entry_handle)120 bool vmci_handle_arr_has_entry(const struct vmci_handle_arr *array,
121 struct vmci_handle entry_handle)
122 {
123 size_t i;
124
125 for (i = 0; i < array->size; i++)
126 if (vmci_handle_is_equal(array->entries[i], entry_handle))
127 return true;
128
129 return false;
130 }
131
132 /*
133 * NULL if the array is empty. Otherwise, a pointer to the array
134 * of VMCI handles in the handle array.
135 */
vmci_handle_arr_get_handles(struct vmci_handle_arr * array)136 struct vmci_handle *vmci_handle_arr_get_handles(struct vmci_handle_arr *array)
137 {
138 if (array->size)
139 return array->entries;
140
141 return NULL;
142 }
143
