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
handle_arr_calc_size(u32 capacity)11 static size_t handle_arr_calc_size(u32 capacity)
12 {
13 return VMCI_HANDLE_ARRAY_HEADER_SIZE +
14 capacity * sizeof(struct vmci_handle);
15 }
16
vmci_handle_arr_create(u32 capacity,u32 max_capacity)17 struct vmci_handle_arr *vmci_handle_arr_create(u32 capacity, u32 max_capacity)
18 {
19 struct vmci_handle_arr *array;
20
21 if (max_capacity == 0 || capacity > max_capacity)
22 return NULL;
23
24 if (capacity == 0)
25 capacity = min((u32)VMCI_HANDLE_ARRAY_DEFAULT_CAPACITY,
26 max_capacity);
27
28 array = kmalloc(handle_arr_calc_size(capacity), GFP_ATOMIC);
29 if (!array)
30 return NULL;
31
32 array->capacity = capacity;
33 array->max_capacity = max_capacity;
34 array->size = 0;
35
36 return array;
37 }
38
vmci_handle_arr_destroy(struct vmci_handle_arr * array)39 void vmci_handle_arr_destroy(struct vmci_handle_arr *array)
40 {
41 kfree(array);
42 }
43
vmci_handle_arr_append_entry(struct vmci_handle_arr ** array_ptr,struct vmci_handle handle)44 int vmci_handle_arr_append_entry(struct vmci_handle_arr **array_ptr,
45 struct vmci_handle handle)
46 {
47 struct vmci_handle_arr *array = *array_ptr;
48
49 if (unlikely(array->size >= array->capacity)) {
50 /* reallocate. */
51 struct vmci_handle_arr *new_array;
52 u32 capacity_bump = min(array->max_capacity - array->capacity,
53 array->capacity);
54 size_t new_size = handle_arr_calc_size(array->capacity +
55 capacity_bump);
56
57 if (array->size >= array->max_capacity)
58 return VMCI_ERROR_NO_MEM;
59
60 new_array = krealloc(array, new_size, GFP_ATOMIC);
61 if (!new_array)
62 return VMCI_ERROR_NO_MEM;
63
64 new_array->capacity += capacity_bump;
65 *array_ptr = array = new_array;
66 }
67
68 array->entries[array->size] = handle;
69 array->size++;
70
71 return VMCI_SUCCESS;
72 }
73
74 /*
75 * Handle that was removed, VMCI_INVALID_HANDLE if entry not found.
76 */
vmci_handle_arr_remove_entry(struct vmci_handle_arr * array,struct vmci_handle entry_handle)77 struct vmci_handle vmci_handle_arr_remove_entry(struct vmci_handle_arr *array,
78 struct vmci_handle entry_handle)
79 {
80 struct vmci_handle handle = VMCI_INVALID_HANDLE;
81 u32 i;
82
83 for (i = 0; i < array->size; i++) {
84 if (vmci_handle_is_equal(array->entries[i], entry_handle)) {
85 handle = array->entries[i];
86 array->size--;
87 array->entries[i] = array->entries[array->size];
88 array->entries[array->size] = VMCI_INVALID_HANDLE;
89 break;
90 }
91 }
92
93 return handle;
94 }
95
96 /*
97 * Handle that was removed, VMCI_INVALID_HANDLE if array was empty.
98 */
vmci_handle_arr_remove_tail(struct vmci_handle_arr * array)99 struct vmci_handle vmci_handle_arr_remove_tail(struct vmci_handle_arr *array)
100 {
101 struct vmci_handle handle = VMCI_INVALID_HANDLE;
102
103 if (array->size) {
104 array->size--;
105 handle = array->entries[array->size];
106 array->entries[array->size] = VMCI_INVALID_HANDLE;
107 }
108
109 return handle;
110 }
111
112 /*
113 * Handle at given index, VMCI_INVALID_HANDLE if invalid index.
114 */
115 struct vmci_handle
vmci_handle_arr_get_entry(const struct vmci_handle_arr * array,u32 index)116 vmci_handle_arr_get_entry(const struct vmci_handle_arr *array, u32 index)
117 {
118 if (unlikely(index >= array->size))
119 return VMCI_INVALID_HANDLE;
120
121 return array->entries[index];
122 }
123
vmci_handle_arr_has_entry(const struct vmci_handle_arr * array,struct vmci_handle entry_handle)124 bool vmci_handle_arr_has_entry(const struct vmci_handle_arr *array,
125 struct vmci_handle entry_handle)
126 {
127 u32 i;
128
129 for (i = 0; i < array->size; i++)
130 if (vmci_handle_is_equal(array->entries[i], entry_handle))
131 return true;
132
133 return false;
134 }
135
136 /*
137 * NULL if the array is empty. Otherwise, a pointer to the array
138 * of VMCI handles in the handle array.
139 */
vmci_handle_arr_get_handles(struct vmci_handle_arr * array)140 struct vmci_handle *vmci_handle_arr_get_handles(struct vmci_handle_arr *array)
141 {
142 if (array->size)
143 return array->entries;
144
145 return NULL;
146 }
147