1 // SPDX-License-Identifier: GPL-2.0 1 // SPDX-License-Identifier: GPL-2.0
2 /* 2 /*
3 * func_utils.h 3 * func_utils.h
4 * 4 *
5 * Utility definitions for USB functions 5 * Utility definitions for USB functions
6 * 6 *
7 * Copyright (c) 2013 Samsung Electronics Co., 7 * Copyright (c) 2013 Samsung Electronics Co., Ltd.
8 * http://www.samsung.com 8 * http://www.samsung.com
9 * 9 *
10 * Author: Andrzej Pietrasiewicz <andrzejtp201 10 * Author: Andrzej Pietrasiewicz <andrzejtp2010@gmail.com>
11 */ 11 */
12 12
13 #ifndef _FUNC_UTILS_H_ 13 #ifndef _FUNC_UTILS_H_
14 #define _FUNC_UTILS_H_ 14 #define _FUNC_UTILS_H_
15 15
16 #include <linux/usb/gadget.h> 16 #include <linux/usb/gadget.h>
17 #include <linux/overflow.h> 17 #include <linux/overflow.h>
18 18
19 /* Variable Length Array Macros ************** 19 /* Variable Length Array Macros **********************************************/
20 #define vla_group(groupname) size_t groupname# 20 #define vla_group(groupname) size_t groupname##__next = 0
21 #define vla_group_size(groupname) groupname##_ 21 #define vla_group_size(groupname) groupname##__next
22 22
23 #define vla_item(groupname, type, name, n) \ 23 #define vla_item(groupname, type, name, n) \
24 size_t groupname##_##name##__offset = 24 size_t groupname##_##name##__offset = ({ \
25 size_t offset = 0; 25 size_t offset = 0; \
26 if (groupname##__next != SIZE_ 26 if (groupname##__next != SIZE_MAX) { \
27 size_t align_mask = __ 27 size_t align_mask = __alignof__(type) - 1; \
28 size_t size = array_si 28 size_t size = array_size(n, sizeof(type)); \
29 offset = (groupname##_ 29 offset = (groupname##__next + align_mask) & \
30 ~align_mask; 30 ~align_mask; \
31 if (check_add_overflow 31 if (check_add_overflow(offset, size, \
32 32 &groupname##__next)) { \
33 groupname##__n 33 groupname##__next = SIZE_MAX; \
34 offset = 0; 34 offset = 0; \
35 } 35 } \
36 } 36 } \
37 offset; 37 offset; \
38 }) 38 })
39 39
40 #define vla_item_with_sz(groupname, type, name 40 #define vla_item_with_sz(groupname, type, name, n) \
41 size_t groupname##_##name##__sz = arra 41 size_t groupname##_##name##__sz = array_size(n, sizeof(type)); \
42 size_t groupname##_##name##__offset = 42 size_t groupname##_##name##__offset = ({ \
43 size_t offset = 0; 43 size_t offset = 0; \
44 if (groupname##__next != SIZE_ 44 if (groupname##__next != SIZE_MAX) { \
45 size_t align_mask = __ 45 size_t align_mask = __alignof__(type) - 1; \
46 offset = (groupname##_ 46 offset = (groupname##__next + align_mask) & \
47 ~align_mask; 47 ~align_mask; \
48 if (check_add_overflow 48 if (check_add_overflow(offset, groupname##_##name##__sz,\
49 49 &groupname##__next)) { \
50 groupname##__n 50 groupname##__next = SIZE_MAX; \
51 offset = 0; 51 offset = 0; \
52 } 52 } \
53 } 53 } \
54 offset; 54 offset; \
55 }) 55 })
56 56
57 #define vla_ptr(ptr, groupname, name) \ 57 #define vla_ptr(ptr, groupname, name) \
58 ((void *) ((char *)ptr + groupname##_# 58 ((void *) ((char *)ptr + groupname##_##name##__offset))
59 59
60 struct usb_ep; 60 struct usb_ep;
61 struct usb_request; 61 struct usb_request;
62 62
63 /** 63 /**
64 * alloc_ep_req - returns a usb_request alloca 64 * alloc_ep_req - returns a usb_request allocated by the gadget driver and
65 * allocates the request's buffer. 65 * allocates the request's buffer.
66 * 66 *
67 * @ep: the endpoint to allocate a usb_request 67 * @ep: the endpoint to allocate a usb_request
68 * @len: usb_requests's buffer suggested size 68 * @len: usb_requests's buffer suggested size
69 * 69 *
70 * In case @ep direction is OUT, the @len will 70 * In case @ep direction is OUT, the @len will be aligned to ep's
71 * wMaxPacketSize. In order to avoid memory le 71 * wMaxPacketSize. In order to avoid memory leaks or drops, *always* use
72 * usb_requests's length (req->length) to refe 72 * usb_requests's length (req->length) to refer to the allocated buffer size.
73 * Requests allocated via alloc_ep_req() *must 73 * Requests allocated via alloc_ep_req() *must* be freed by free_ep_req().
74 */ 74 */
75 struct usb_request *alloc_ep_req(struct usb_ep 75 struct usb_request *alloc_ep_req(struct usb_ep *ep, size_t len);
76 76
77 /* Frees a usb_request previously allocated by 77 /* Frees a usb_request previously allocated by alloc_ep_req() */
78 static inline void free_ep_req(struct usb_ep * 78 static inline void free_ep_req(struct usb_ep *ep, struct usb_request *req)
79 { 79 {
80 WARN_ON(req->buf == NULL); 80 WARN_ON(req->buf == NULL);
81 kfree(req->buf); 81 kfree(req->buf);
82 req->buf = NULL; 82 req->buf = NULL;
83 usb_ep_free_request(ep, req); 83 usb_ep_free_request(ep, req);
84 } 84 }
85 85
86 #endif /* _FUNC_UTILS_H_ */ 86 #endif /* _FUNC_UTILS_H_ */
87 87
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