1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * VMware VMCI Driver
4 *
5 * Copyright (C) 2012 VMware, Inc. All rights reserved.
6 */
7
8 #include <linux/slab.h>
9 #include "vmci_handle_array.h"
10
vmci_handle_arr_create(u32 capacity,u32 max_capacity)11 struct vmci_handle_arr *vmci_handle_arr_create(u32 capacity, u32 max_capacity)
12 {
13 struct vmci_handle_arr *array;
14
15 if (max_capacity == 0 || capacity > max_capacity)
16 return NULL;
17
18 if (capacity == 0)
19 capacity = min((u32)VMCI_HANDLE_ARRAY_DEFAULT_CAPACITY,
20 max_capacity);
21
22 array = kmalloc(struct_size(array, entries, capacity), GFP_ATOMIC);
23 if (!array)
24 return NULL;
25
26 array->capacity = capacity;
27 array->max_capacity = max_capacity;
28 array->size = 0;
29
30 return array;
31 }
32
vmci_handle_arr_destroy(struct vmci_handle_arr * array)33 void vmci_handle_arr_destroy(struct vmci_handle_arr *array)
34 {
35 kfree(array);
36 }
37
vmci_handle_arr_append_entry(struct vmci_handle_arr ** array_ptr,struct vmci_handle handle)38 int vmci_handle_arr_append_entry(struct vmci_handle_arr **array_ptr,
39 struct vmci_handle handle)
40 {
41 struct vmci_handle_arr *array = *array_ptr;
42
43 if (unlikely(array->size >= array->capacity)) {
44 /* reallocate. */
45 struct vmci_handle_arr *new_array;
46 u32 capacity_bump = min(array->max_capacity - array->capacity,
47 array->capacity);
48 size_t new_size = struct_size(array, entries,
49 size_add(array->capacity, capacity_bump));
50
51 if (array->size >= array->max_capacity)
52 return VMCI_ERROR_NO_MEM;
53
54 new_array = krealloc(array, new_size, GFP_ATOMIC);
55 if (!new_array)
56 return VMCI_ERROR_NO_MEM;
57
58 new_array->capacity += capacity_bump;
59 *array_ptr = array = new_array;
60 }
61
62 array->entries[array->size] = handle;
63 array->size++;
64
65 return VMCI_SUCCESS;
66 }
67
68 /*
69 * Handle that was removed, VMCI_INVALID_HANDLE if entry not found.
70 */
vmci_handle_arr_remove_entry(struct vmci_handle_arr * array,struct vmci_handle entry_handle)71 struct vmci_handle vmci_handle_arr_remove_entry(struct vmci_handle_arr *array,
72 struct vmci_handle entry_handle)
73 {
74 struct vmci_handle handle = VMCI_INVALID_HANDLE;
75 u32 i;
76
77 for (i = 0; i < array->size; i++) {
78 if (vmci_handle_is_equal(array->entries[i], entry_handle)) {
79 handle = array->entries[i];
80 array->size--;
81 array->entries[i] = array->entries[array->size];
82 array->entries[array->size] = VMCI_INVALID_HANDLE;
83 break;
84 }
85 }
86
87 return handle;
88 }
89
90 /*
91 * Handle that was removed, VMCI_INVALID_HANDLE if array was empty.
92 */
vmci_handle_arr_remove_tail(struct vmci_handle_arr * array)93 struct vmci_handle vmci_handle_arr_remove_tail(struct vmci_handle_arr *array)
94 {
95 struct vmci_handle handle = VMCI_INVALID_HANDLE;
96
97 if (array->size) {
98 array->size--;
99 handle = array->entries[array->size];
100 array->entries[array->size] = VMCI_INVALID_HANDLE;
101 }
102
103 return handle;
104 }
105
106 /*
107 * Handle at given index, VMCI_INVALID_HANDLE if invalid index.
108 */
109 struct vmci_handle
vmci_handle_arr_get_entry(const struct vmci_handle_arr * array,u32 index)110 vmci_handle_arr_get_entry(const struct vmci_handle_arr *array, u32 index)
111 {
112 if (unlikely(index >= array->size))
113 return VMCI_INVALID_HANDLE;
114
115 return array->entries[index];
116 }
117
vmci_handle_arr_has_entry(const struct vmci_handle_arr * array,struct vmci_handle entry_handle)118 bool vmci_handle_arr_has_entry(const struct vmci_handle_arr *array,
119 struct vmci_handle entry_handle)
120 {
121 u32 i;
122
123 for (i = 0; i < array->size; i++)
124 if (vmci_handle_is_equal(array->entries[i], entry_handle))
125 return true;
126
127 return false;
128 }
129
130 /*
131 * NULL if the array is empty. Otherwise, a pointer to the array
132 * of VMCI handles in the handle array.
133 */
vmci_handle_arr_get_handles(struct vmci_handle_arr * array)134 struct vmci_handle *vmci_handle_arr_get_handles(struct vmci_handle_arr *array)
135 {
136 if (array->size)
137 return array->entries;
138
139 return NULL;
140 }
141