diff options
Diffstat (limited to 'drivers/misc/vmw_vmci/vmci_handle_array.c')
-rw-r--r-- | drivers/misc/vmw_vmci/vmci_handle_array.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/drivers/misc/vmw_vmci/vmci_handle_array.c b/drivers/misc/vmw_vmci/vmci_handle_array.c new file mode 100644 index 000000000000..344973a0fb0a --- /dev/null +++ b/drivers/misc/vmw_vmci/vmci_handle_array.c @@ -0,0 +1,142 @@ +/* + * VMware VMCI Driver + * + * Copyright (C) 2012 VMware, Inc. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation version 2 and no later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +#include <linux/slab.h> +#include "vmci_handle_array.h" + +static size_t handle_arr_calc_size(size_t capacity) +{ + return sizeof(struct vmci_handle_arr) + + capacity * sizeof(struct vmci_handle); +} + +struct vmci_handle_arr *vmci_handle_arr_create(size_t capacity) +{ + struct vmci_handle_arr *array; + + if (capacity == 0) + capacity = VMCI_HANDLE_ARRAY_DEFAULT_SIZE; + + array = kmalloc(handle_arr_calc_size(capacity), GFP_ATOMIC); + if (!array) + return NULL; + + array->capacity = capacity; + array->size = 0; + + return array; +} + +void vmci_handle_arr_destroy(struct vmci_handle_arr *array) +{ + kfree(array); +} + +void vmci_handle_arr_append_entry(struct vmci_handle_arr **array_ptr, + struct vmci_handle handle) +{ + struct vmci_handle_arr *array = *array_ptr; + + if (unlikely(array->size >= array->capacity)) { + /* reallocate. */ + struct vmci_handle_arr *new_array; + size_t new_capacity = array->capacity * VMCI_ARR_CAP_MULT; + size_t new_size = handle_arr_calc_size(new_capacity); + + new_array = krealloc(array, new_size, GFP_ATOMIC); + if (!new_array) + return; + + new_array->capacity = new_capacity; + *array_ptr = array = new_array; + } + + array->entries[array->size] = handle; + array->size++; +} + +/* + * Handle that was removed, VMCI_INVALID_HANDLE if entry not found. + */ +struct vmci_handle vmci_handle_arr_remove_entry(struct vmci_handle_arr *array, + struct vmci_handle entry_handle) +{ + struct vmci_handle handle = VMCI_INVALID_HANDLE; + size_t i; + + for (i = 0; i < array->size; i++) { + if (vmci_handle_is_equal(array->entries[i], entry_handle)) { + handle = array->entries[i]; + array->size--; + array->entries[i] = array->entries[array->size]; + array->entries[array->size] = VMCI_INVALID_HANDLE; + break; + } + } + + return handle; +} + +/* + * Handle that was removed, VMCI_INVALID_HANDLE if array was empty. + */ +struct vmci_handle vmci_handle_arr_remove_tail(struct vmci_handle_arr *array) +{ + struct vmci_handle handle = VMCI_INVALID_HANDLE; + + if (array->size) { + array->size--; + handle = array->entries[array->size]; + array->entries[array->size] = VMCI_INVALID_HANDLE; + } + + return handle; +} + +/* + * Handle at given index, VMCI_INVALID_HANDLE if invalid index. + */ +struct vmci_handle +vmci_handle_arr_get_entry(const struct vmci_handle_arr *array, size_t index) +{ + if (unlikely(index >= array->size)) + return VMCI_INVALID_HANDLE; + + return array->entries[index]; +} + +bool vmci_handle_arr_has_entry(const struct vmci_handle_arr *array, + struct vmci_handle entry_handle) +{ + size_t i; + + for (i = 0; i < array->size; i++) + if (vmci_handle_is_equal(array->entries[i], entry_handle)) + return true; + + return false; +} + +/* + * NULL if the array is empty. Otherwise, a pointer to the array + * of VMCI handles in the handle array. + */ +struct vmci_handle *vmci_handle_arr_get_handles(struct vmci_handle_arr *array) +{ + if (array->size) + return array->entries; + + return NULL; +} |