diff options
Diffstat (limited to 'include/linux/kfifo.h')
-rw-r--r-- | include/linux/kfifo.h | 1195 |
1 files changed, 713 insertions, 482 deletions
diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h index e117b1aee69c..62dbee554f60 100644 --- a/include/linux/kfifo.h +++ b/include/linux/kfifo.h | |||
@@ -1,8 +1,7 @@ | |||
1 | /* | 1 | /* |
2 | * A generic kernel FIFO implementation. | 2 | * A generic kernel FIFO implementation |
3 | * | 3 | * |
4 | * Copyright (C) 2009 Stefani Seibold <stefani@seibold.net> | 4 | * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net> |
5 | * Copyright (C) 2004 Stelian Pop <stelian@popies.net> | ||
6 | * | 5 | * |
7 | * This program is free software; you can redistribute it and/or modify | 6 | * This program is free software; you can redistribute it and/or modify |
8 | * it under the terms of the GNU General Public License as published by | 7 | * it under the terms of the GNU General Public License as published by |
@@ -20,8 +19,11 @@ | |||
20 | * | 19 | * |
21 | */ | 20 | */ |
22 | 21 | ||
22 | #ifndef _LINUX_KFIFO_H | ||
23 | #define _LINUX_KFIFO_H | ||
24 | |||
23 | /* | 25 | /* |
24 | * Howto porting drivers to the new generic fifo API: | 26 | * How to porting drivers to the new generic FIFO API: |
25 | * | 27 | * |
26 | * - Modify the declaration of the "struct kfifo *" object into a | 28 | * - Modify the declaration of the "struct kfifo *" object into a |
27 | * in-place "struct kfifo" object | 29 | * in-place "struct kfifo" object |
@@ -30,586 +32,815 @@ | |||
30 | * passed as the first argument to this functions | 32 | * passed as the first argument to this functions |
31 | * - Replace the use of __kfifo_put into kfifo_in and __kfifo_get | 33 | * - Replace the use of __kfifo_put into kfifo_in and __kfifo_get |
32 | * into kfifo_out | 34 | * into kfifo_out |
33 | * - Replace the use of kfifo_put into kfifo_in_locked and kfifo_get | 35 | * - Replace the use of kfifo_put into kfifo_in_spinlocked and kfifo_get |
34 | * into kfifo_out_locked | 36 | * into kfifo_out_spinlocked |
35 | * Note: the spinlock pointer formerly passed to kfifo_init/kfifo_alloc | 37 | * Note: the spinlock pointer formerly passed to kfifo_init/kfifo_alloc |
36 | * must be passed now to the kfifo_in_locked and kfifo_out_locked | 38 | * must be passed now to the kfifo_in_spinlocked and kfifo_out_spinlocked |
37 | * as the last parameter. | 39 | * as the last parameter |
38 | * - All formerly name __kfifo_* functions has been renamed into kfifo_* | 40 | * - The formerly __kfifo_* functions are renamed into kfifo_* |
39 | */ | 41 | */ |
40 | 42 | ||
41 | #ifndef _LINUX_KFIFO_H | 43 | /* |
42 | #define _LINUX_KFIFO_H | 44 | * Note about locking : There is no locking required until only * one reader |
45 | * and one writer is using the fifo and no kfifo_reset() will be * called | ||
46 | * kfifo_reset_out() can be safely used, until it will be only called | ||
47 | * in the reader thread. | ||
48 | * For multiple writer and one reader there is only a need to lock the writer. | ||
49 | * And vice versa for only one writer and multiple reader there is only a need | ||
50 | * to lock the reader. | ||
51 | */ | ||
43 | 52 | ||
44 | #include <linux/kernel.h> | 53 | #include <linux/kernel.h> |
45 | #include <linux/spinlock.h> | 54 | #include <linux/spinlock.h> |
46 | 55 | #include <linux/stddef.h> | |
47 | struct kfifo { | 56 | #include <linux/scatterlist.h> |
48 | unsigned char *buffer; /* the buffer holding the data */ | 57 | |
49 | unsigned int size; /* the size of the allocated buffer */ | 58 | struct __kfifo { |
50 | unsigned int in; /* data is added at offset (in % size) */ | 59 | unsigned int in; |
51 | unsigned int out; /* data is extracted from off. (out % size) */ | 60 | unsigned int out; |
61 | unsigned int mask; | ||
62 | unsigned int esize; | ||
63 | void *data; | ||
52 | }; | 64 | }; |
53 | 65 | ||
54 | /* | 66 | #define __STRUCT_KFIFO_COMMON(datatype, recsize, ptrtype) \ |
55 | * Macros for declaration and initialization of the kfifo datatype | 67 | union { \ |
56 | */ | 68 | struct __kfifo kfifo; \ |
57 | 69 | datatype *type; \ | |
58 | /* helper macro */ | 70 | char (*rectype)[recsize]; \ |
59 | #define __kfifo_initializer(s, b) \ | 71 | ptrtype *ptr; \ |
60 | (struct kfifo) { \ | 72 | const ptrtype *ptr_const; \ |
61 | .size = s, \ | ||
62 | .in = 0, \ | ||
63 | .out = 0, \ | ||
64 | .buffer = b \ | ||
65 | } | 73 | } |
66 | 74 | ||
67 | /** | 75 | #define __STRUCT_KFIFO(type, size, recsize, ptrtype) \ |
68 | * DECLARE_KFIFO - macro to declare a kfifo and the associated buffer | 76 | { \ |
69 | * @name: name of the declared kfifo datatype | 77 | __STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \ |
70 | * @size: size of the fifo buffer. Must be a power of two. | 78 | type buf[((size < 2) || (size & (size - 1))) ? -1 : size]; \ |
71 | * | ||
72 | * Note1: the macro can be used inside struct or union declaration | ||
73 | * Note2: the macro creates two objects: | ||
74 | * A kfifo object with the given name and a buffer for the kfifo | ||
75 | * object named name##kfifo_buffer | ||
76 | */ | ||
77 | #define DECLARE_KFIFO(name, size) \ | ||
78 | union { \ | ||
79 | struct kfifo name; \ | ||
80 | unsigned char name##kfifo_buffer[size + sizeof(struct kfifo)]; \ | ||
81 | } | 79 | } |
82 | 80 | ||
83 | /** | 81 | #define STRUCT_KFIFO(type, size) \ |
84 | * INIT_KFIFO - Initialize a kfifo declared by DECLARE_KFIFO | 82 | struct __STRUCT_KFIFO(type, size, 0, type) |
85 | * @name: name of the declared kfifo datatype | 83 | |
84 | #define __STRUCT_KFIFO_PTR(type, recsize, ptrtype) \ | ||
85 | { \ | ||
86 | __STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \ | ||
87 | type buf[0]; \ | ||
88 | } | ||
89 | |||
90 | #define STRUCT_KFIFO_PTR(type) \ | ||
91 | struct __STRUCT_KFIFO_PTR(type, 0, type) | ||
92 | |||
93 | /* | ||
94 | * define compatibility "struct kfifo" for dynamic allocated fifos | ||
86 | */ | 95 | */ |
87 | #define INIT_KFIFO(name) \ | 96 | struct kfifo __STRUCT_KFIFO_PTR(unsigned char, 0, void); |
88 | name = __kfifo_initializer(sizeof(name##kfifo_buffer) - \ | ||
89 | sizeof(struct kfifo), \ | ||
90 | name##kfifo_buffer + sizeof(struct kfifo)) | ||
91 | 97 | ||
92 | /** | 98 | #define STRUCT_KFIFO_REC_1(size) \ |
93 | * DEFINE_KFIFO - macro to define and initialize a kfifo | 99 | struct __STRUCT_KFIFO(unsigned char, size, 1, void) |
94 | * @name: name of the declared kfifo datatype | 100 | |
95 | * @size: size of the fifo buffer. Must be a power of two. | 101 | #define STRUCT_KFIFO_REC_2(size) \ |
96 | * | 102 | struct __STRUCT_KFIFO(unsigned char, size, 2, void) |
97 | * Note1: the macro can be used for global and local kfifo data type variables | 103 | |
98 | * Note2: the macro creates two objects: | 104 | /* |
99 | * A kfifo object with the given name and a buffer for the kfifo | 105 | * define kfifo_rec types |
100 | * object named name##kfifo_buffer | ||
101 | */ | 106 | */ |
102 | #define DEFINE_KFIFO(name, size) \ | 107 | struct kfifo_rec_ptr_1 __STRUCT_KFIFO_PTR(unsigned char, 1, void); |
103 | unsigned char name##kfifo_buffer[size]; \ | 108 | struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void); |
104 | struct kfifo name = __kfifo_initializer(size, name##kfifo_buffer) | ||
105 | 109 | ||
106 | extern void kfifo_init(struct kfifo *fifo, void *buffer, | 110 | /* |
107 | unsigned int size); | 111 | * helper macro to distinguish between real in place fifo where the fifo |
108 | extern __must_check int kfifo_alloc(struct kfifo *fifo, unsigned int size, | 112 | * array is a part of the structure and the fifo type where the array is |
109 | gfp_t gfp_mask); | 113 | * outside of the fifo structure. |
110 | extern void kfifo_free(struct kfifo *fifo); | 114 | */ |
111 | extern unsigned int kfifo_in(struct kfifo *fifo, | 115 | #define __is_kfifo_ptr(fifo) (sizeof(*fifo) == sizeof(struct __kfifo)) |
112 | const void *from, unsigned int len); | ||
113 | extern __must_check unsigned int kfifo_out(struct kfifo *fifo, | ||
114 | void *to, unsigned int len); | ||
115 | extern __must_check unsigned int kfifo_out_peek(struct kfifo *fifo, | ||
116 | void *to, unsigned int len, unsigned offset); | ||
117 | 116 | ||
118 | /** | 117 | /** |
119 | * kfifo_initialized - Check if kfifo is initialized. | 118 | * DECLARE_KFIFO_PTR - macro to declare a fifo pointer object |
120 | * @fifo: fifo to check | 119 | * @fifo: name of the declared fifo |
121 | * Return %true if FIFO is initialized, otherwise %false. | 120 | * @type: type of the fifo elements |
122 | * Assumes the fifo was 0 before. | ||
123 | */ | 121 | */ |
124 | static inline bool kfifo_initialized(struct kfifo *fifo) | 122 | #define DECLARE_KFIFO_PTR(fifo, type) STRUCT_KFIFO_PTR(type) fifo |
125 | { | ||
126 | return fifo->buffer != NULL; | ||
127 | } | ||
128 | 123 | ||
129 | /** | 124 | /** |
130 | * kfifo_reset - removes the entire FIFO contents | 125 | * DECLARE_KFIFO - macro to declare a fifo object |
131 | * @fifo: the fifo to be emptied. | 126 | * @fifo: name of the declared fifo |
127 | * @type: type of the fifo elements | ||
128 | * @size: the number of elements in the fifo, this must be a power of 2 | ||
132 | */ | 129 | */ |
133 | static inline void kfifo_reset(struct kfifo *fifo) | 130 | #define DECLARE_KFIFO(fifo, type, size) STRUCT_KFIFO(type, size) fifo |
134 | { | ||
135 | fifo->in = fifo->out = 0; | ||
136 | } | ||
137 | 131 | ||
138 | /** | 132 | /** |
139 | * kfifo_reset_out - skip FIFO contents | 133 | * INIT_KFIFO - Initialize a fifo declared by DECLARE_KFIFO |
140 | * @fifo: the fifo to be emptied. | 134 | * @fifo: name of the declared fifo datatype |
141 | */ | 135 | */ |
142 | static inline void kfifo_reset_out(struct kfifo *fifo) | 136 | #define INIT_KFIFO(fifo) \ |
143 | { | 137 | (void)({ \ |
144 | smp_mb(); | 138 | typeof(&(fifo)) __tmp = &(fifo); \ |
145 | fifo->out = fifo->in; | 139 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
146 | } | 140 | __kfifo->in = 0; \ |
141 | __kfifo->out = 0; \ | ||
142 | __kfifo->mask = __is_kfifo_ptr(__tmp) ? 0 : ARRAY_SIZE(__tmp->buf) - 1;\ | ||
143 | __kfifo->esize = sizeof(*__tmp->buf); \ | ||
144 | __kfifo->data = __is_kfifo_ptr(__tmp) ? NULL : __tmp->buf; \ | ||
145 | }) | ||
147 | 146 | ||
148 | /** | 147 | /** |
149 | * kfifo_size - returns the size of the fifo in bytes | 148 | * DEFINE_KFIFO - macro to define and initialize a fifo |
150 | * @fifo: the fifo to be used. | 149 | * @fifo: name of the declared fifo datatype |
151 | */ | 150 | * @type: type of the fifo elements |
152 | static inline __must_check unsigned int kfifo_size(struct kfifo *fifo) | 151 | * @size: the number of elements in the fifo, this must be a power of 2 |
152 | * | ||
153 | * Note: the macro can be used for global and local fifo data type variables. | ||
154 | */ | ||
155 | #define DEFINE_KFIFO(fifo, type, size) \ | ||
156 | DECLARE_KFIFO(fifo, type, size) = \ | ||
157 | (typeof(fifo)) { \ | ||
158 | { \ | ||
159 | { \ | ||
160 | .in = 0, \ | ||
161 | .out = 0, \ | ||
162 | .mask = __is_kfifo_ptr(&(fifo)) ? \ | ||
163 | 0 : \ | ||
164 | ARRAY_SIZE((fifo).buf) - 1, \ | ||
165 | .esize = sizeof(*(fifo).buf), \ | ||
166 | .data = __is_kfifo_ptr(&(fifo)) ? \ | ||
167 | NULL : \ | ||
168 | (fifo).buf, \ | ||
169 | } \ | ||
170 | } \ | ||
171 | } | ||
172 | |||
173 | |||
174 | static inline unsigned int __must_check | ||
175 | __kfifo_must_check_helper(unsigned int val) | ||
153 | { | 176 | { |
154 | return fifo->size; | 177 | return val; |
155 | } | 178 | } |
156 | 179 | ||
157 | /** | 180 | /** |
158 | * kfifo_len - returns the number of used bytes in the FIFO | 181 | * kfifo_initialized - Check if the fifo is initialized |
159 | * @fifo: the fifo to be used. | 182 | * @fifo: address of the fifo to check |
183 | * | ||
184 | * Return %true if fifo is initialized, otherwise %false. | ||
185 | * Assumes the fifo was 0 before. | ||
160 | */ | 186 | */ |
161 | static inline unsigned int kfifo_len(struct kfifo *fifo) | 187 | #define kfifo_initialized(fifo) ((fifo)->kfifo.mask) |
162 | { | ||
163 | register unsigned int out; | ||
164 | |||
165 | out = fifo->out; | ||
166 | smp_rmb(); | ||
167 | return fifo->in - out; | ||
168 | } | ||
169 | 188 | ||
170 | /** | 189 | /** |
171 | * kfifo_is_empty - returns true if the fifo is empty | 190 | * kfifo_esize - returns the size of the element managed by the fifo |
172 | * @fifo: the fifo to be used. | 191 | * @fifo: address of the fifo to be used |
173 | */ | 192 | */ |
174 | static inline __must_check int kfifo_is_empty(struct kfifo *fifo) | 193 | #define kfifo_esize(fifo) ((fifo)->kfifo.esize) |
175 | { | ||
176 | return fifo->in == fifo->out; | ||
177 | } | ||
178 | 194 | ||
179 | /** | 195 | /** |
180 | * kfifo_is_full - returns true if the fifo is full | 196 | * kfifo_recsize - returns the size of the record length field |
181 | * @fifo: the fifo to be used. | 197 | * @fifo: address of the fifo to be used |
182 | */ | 198 | */ |
183 | static inline __must_check int kfifo_is_full(struct kfifo *fifo) | 199 | #define kfifo_recsize(fifo) (sizeof(*(fifo)->rectype)) |
184 | { | ||
185 | return kfifo_len(fifo) == kfifo_size(fifo); | ||
186 | } | ||
187 | 200 | ||
188 | /** | 201 | /** |
189 | * kfifo_avail - returns the number of bytes available in the FIFO | 202 | * kfifo_size - returns the size of the fifo in elements |
190 | * @fifo: the fifo to be used. | 203 | * @fifo: address of the fifo to be used |
191 | */ | 204 | */ |
192 | static inline __must_check unsigned int kfifo_avail(struct kfifo *fifo) | 205 | #define kfifo_size(fifo) ((fifo)->kfifo.mask + 1) |
193 | { | ||
194 | return kfifo_size(fifo) - kfifo_len(fifo); | ||
195 | } | ||
196 | 206 | ||
197 | /** | 207 | /** |
198 | * kfifo_in_locked - puts some data into the FIFO using a spinlock for locking | 208 | * kfifo_reset - removes the entire fifo content |
199 | * @fifo: the fifo to be used. | 209 | * @fifo: address of the fifo to be used |
200 | * @from: the data to be added. | ||
201 | * @n: the length of the data to be added. | ||
202 | * @lock: pointer to the spinlock to use for locking. | ||
203 | * | 210 | * |
204 | * This function copies at most @len bytes from the @from buffer into | 211 | * Note: usage of kfifo_reset() is dangerous. It should be only called when the |
205 | * the FIFO depending on the free space, and returns the number of | 212 | * fifo is exclusived locked or when it is secured that no other thread is |
206 | * bytes copied. | 213 | * accessing the fifo. |
207 | */ | 214 | */ |
208 | static inline unsigned int kfifo_in_locked(struct kfifo *fifo, | 215 | #define kfifo_reset(fifo) \ |
209 | const void *from, unsigned int n, spinlock_t *lock) | 216 | (void)({ \ |
210 | { | 217 | typeof((fifo) + 1) __tmp = (fifo); \ |
211 | unsigned long flags; | 218 | __tmp->kfifo.in = __tmp->kfifo.out = 0; \ |
212 | unsigned int ret; | 219 | }) |
213 | |||
214 | spin_lock_irqsave(lock, flags); | ||
215 | |||
216 | ret = kfifo_in(fifo, from, n); | ||
217 | |||
218 | spin_unlock_irqrestore(lock, flags); | ||
219 | |||
220 | return ret; | ||
221 | } | ||
222 | 220 | ||
223 | /** | 221 | /** |
224 | * kfifo_out_locked - gets some data from the FIFO using a spinlock for locking | 222 | * kfifo_reset_out - skip fifo content |
225 | * @fifo: the fifo to be used. | 223 | * @fifo: address of the fifo to be used |
226 | * @to: where the data must be copied. | ||
227 | * @n: the size of the destination buffer. | ||
228 | * @lock: pointer to the spinlock to use for locking. | ||
229 | * | 224 | * |
230 | * This function copies at most @len bytes from the FIFO into the | 225 | * Note: The usage of kfifo_reset_out() is safe until it will be only called |
231 | * @to buffer and returns the number of copied bytes. | 226 | * from the reader thread and there is only one concurrent reader. Otherwise |
232 | */ | 227 | * it is dangerous and must be handled in the same way as kfifo_reset(). |
233 | static inline __must_check unsigned int kfifo_out_locked(struct kfifo *fifo, | ||
234 | void *to, unsigned int n, spinlock_t *lock) | ||
235 | { | ||
236 | unsigned long flags; | ||
237 | unsigned int ret; | ||
238 | |||
239 | spin_lock_irqsave(lock, flags); | ||
240 | |||
241 | ret = kfifo_out(fifo, to, n); | ||
242 | |||
243 | spin_unlock_irqrestore(lock, flags); | ||
244 | |||
245 | return ret; | ||
246 | } | ||
247 | |||
248 | extern void kfifo_skip(struct kfifo *fifo, unsigned int len); | ||
249 | |||
250 | extern __must_check int kfifo_from_user(struct kfifo *fifo, | ||
251 | const void __user *from, unsigned int n, unsigned *lenout); | ||
252 | |||
253 | extern __must_check int kfifo_to_user(struct kfifo *fifo, | ||
254 | void __user *to, unsigned int n, unsigned *lenout); | ||
255 | |||
256 | /* | ||
257 | * __kfifo_add_out internal helper function for updating the out offset | ||
258 | */ | 228 | */ |
259 | static inline void __kfifo_add_out(struct kfifo *fifo, | 229 | #define kfifo_reset_out(fifo) \ |
260 | unsigned int off) | 230 | (void)({ \ |
261 | { | 231 | typeof((fifo) + 1) __tmp = (fifo); \ |
262 | smp_mb(); | 232 | __tmp->kfifo.out = __tmp->kfifo.in; \ |
263 | fifo->out += off; | 233 | }) |
264 | } | ||
265 | 234 | ||
266 | /* | 235 | /** |
267 | * __kfifo_add_in internal helper function for updating the in offset | 236 | * kfifo_len - returns the number of used elements in the fifo |
237 | * @fifo: address of the fifo to be used | ||
268 | */ | 238 | */ |
269 | static inline void __kfifo_add_in(struct kfifo *fifo, | 239 | #define kfifo_len(fifo) \ |
270 | unsigned int off) | 240 | ({ \ |
271 | { | 241 | typeof((fifo) + 1) __tmpl = (fifo); \ |
272 | smp_wmb(); | 242 | __tmpl->kfifo.in - __tmpl->kfifo.out; \ |
273 | fifo->in += off; | 243 | }) |
274 | } | ||
275 | 244 | ||
276 | /* | 245 | /** |
277 | * __kfifo_off internal helper function for calculating the index of a | 246 | * kfifo_is_empty - returns true if the fifo is empty |
278 | * given offeset | 247 | * @fifo: address of the fifo to be used |
279 | */ | 248 | */ |
280 | static inline unsigned int __kfifo_off(struct kfifo *fifo, unsigned int off) | 249 | #define kfifo_is_empty(fifo) \ |
281 | { | 250 | ({ \ |
282 | return off & (fifo->size - 1); | 251 | typeof((fifo) + 1) __tmpq = (fifo); \ |
283 | } | 252 | __tmpq->kfifo.in == __tmpq->kfifo.out; \ |
253 | }) | ||
284 | 254 | ||
285 | /* | 255 | /** |
286 | * __kfifo_peek_n internal helper function for determinate the length of | 256 | * kfifo_is_full - returns true if the fifo is full |
287 | * the next record in the fifo | 257 | * @fifo: address of the fifo to be used |
288 | */ | 258 | */ |
289 | static inline unsigned int __kfifo_peek_n(struct kfifo *fifo, | 259 | #define kfifo_is_full(fifo) \ |
290 | unsigned int recsize) | 260 | ({ \ |
291 | { | 261 | typeof((fifo) + 1) __tmpq = (fifo); \ |
292 | #define __KFIFO_GET(fifo, off, shift) \ | 262 | kfifo_len(__tmpq) > __tmpq->kfifo.mask; \ |
293 | ((fifo)->buffer[__kfifo_off((fifo), (fifo)->out+(off))] << (shift)) | 263 | }) |
294 | 264 | ||
295 | unsigned int l; | 265 | /** |
266 | * kfifo_avail - returns the number of unused elements in the fifo | ||
267 | * @fifo: address of the fifo to be used | ||
268 | */ | ||
269 | #define kfifo_avail(fifo) \ | ||
270 | __kfifo_must_check_helper( \ | ||
271 | ({ \ | ||
272 | typeof((fifo) + 1) __tmpq = (fifo); \ | ||
273 | const size_t __recsize = sizeof(*__tmpq->rectype); \ | ||
274 | unsigned int __avail = kfifo_size(__tmpq) - kfifo_len(__tmpq); \ | ||
275 | (__recsize) ? ((__avail <= __recsize) ? 0 : \ | ||
276 | __kfifo_max_r(__avail - __recsize, __recsize)) : \ | ||
277 | __avail; \ | ||
278 | }) \ | ||
279 | ) | ||
296 | 280 | ||
297 | l = __KFIFO_GET(fifo, 0, 0); | 281 | /** |
282 | * kfifo_skip - skip output data | ||
283 | * @fifo: address of the fifo to be used | ||
284 | */ | ||
285 | #define kfifo_skip(fifo) \ | ||
286 | (void)({ \ | ||
287 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
288 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
289 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
290 | if (__recsize) \ | ||
291 | __kfifo_skip_r(__kfifo, __recsize); \ | ||
292 | else \ | ||
293 | __kfifo->out++; \ | ||
294 | }) | ||
298 | 295 | ||
299 | if (--recsize) | 296 | /** |
300 | l |= __KFIFO_GET(fifo, 1, 8); | 297 | * kfifo_peek_len - gets the size of the next fifo record |
298 | * @fifo: address of the fifo to be used | ||
299 | * | ||
300 | * This function returns the size of the next fifo record in number of bytes. | ||
301 | */ | ||
302 | #define kfifo_peek_len(fifo) \ | ||
303 | __kfifo_must_check_helper( \ | ||
304 | ({ \ | ||
305 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
306 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
307 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
308 | (!__recsize) ? kfifo_len(__tmp) * sizeof(*__tmp->type) : \ | ||
309 | __kfifo_len_r(__kfifo, __recsize); \ | ||
310 | }) \ | ||
311 | ) | ||
301 | 312 | ||
302 | return l; | 313 | /** |
303 | #undef __KFIFO_GET | 314 | * kfifo_alloc - dynamically allocates a new fifo buffer |
304 | } | 315 | * @fifo: pointer to the fifo |
316 | * @size: the number of elements in the fifo, this must be a power of 2 | ||
317 | * @gfp_mask: get_free_pages mask, passed to kmalloc() | ||
318 | * | ||
319 | * This macro dynamically allocates a new fifo buffer. | ||
320 | * | ||
321 | * The numer of elements will be rounded-up to a power of 2. | ||
322 | * The fifo will be release with kfifo_free(). | ||
323 | * Return 0 if no error, otherwise an error code. | ||
324 | */ | ||
325 | #define kfifo_alloc(fifo, size, gfp_mask) \ | ||
326 | __kfifo_must_check_helper( \ | ||
327 | ({ \ | ||
328 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
329 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
330 | __is_kfifo_ptr(__tmp) ? \ | ||
331 | __kfifo_alloc(__kfifo, size, sizeof(*__tmp->type), gfp_mask) : \ | ||
332 | -EINVAL; \ | ||
333 | }) \ | ||
334 | ) | ||
305 | 335 | ||
306 | /* | 336 | /** |
307 | * __kfifo_poke_n internal helper function for storing the length of | 337 | * kfifo_free - frees the fifo |
308 | * the next record into the fifo | 338 | * @fifo: the fifo to be freed |
309 | */ | 339 | */ |
310 | static inline void __kfifo_poke_n(struct kfifo *fifo, | 340 | #define kfifo_free(fifo) \ |
311 | unsigned int recsize, unsigned int n) | 341 | ({ \ |
312 | { | 342 | typeof((fifo) + 1) __tmp = (fifo); \ |
313 | #define __KFIFO_PUT(fifo, off, val, shift) \ | 343 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
314 | ( \ | 344 | if (__is_kfifo_ptr(__tmp)) \ |
315 | (fifo)->buffer[__kfifo_off((fifo), (fifo)->in+(off))] = \ | 345 | __kfifo_free(__kfifo); \ |
316 | (unsigned char)((val) >> (shift)) \ | 346 | }) |
317 | ) | ||
318 | 347 | ||
319 | __KFIFO_PUT(fifo, 0, n, 0); | 348 | /** |
349 | * kfifo_init - initialize a fifo using a preallocated buffer | ||
350 | * @fifo: the fifo to assign the buffer | ||
351 | * @buffer: the preallocated buffer to be used | ||
352 | * @size: the size of the internal buffer, this have to be a power of 2 | ||
353 | * | ||
354 | * This macro initialize a fifo using a preallocated buffer. | ||
355 | * | ||
356 | * The numer of elements will be rounded-up to a power of 2. | ||
357 | * Return 0 if no error, otherwise an error code. | ||
358 | */ | ||
359 | #define kfifo_init(fifo, buffer, size) \ | ||
360 | ({ \ | ||
361 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
362 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
363 | __is_kfifo_ptr(__tmp) ? \ | ||
364 | __kfifo_init(__kfifo, buffer, size, sizeof(*__tmp->type)) : \ | ||
365 | -EINVAL; \ | ||
366 | }) | ||
320 | 367 | ||
321 | if (--recsize) | 368 | /** |
322 | __KFIFO_PUT(fifo, 1, n, 8); | 369 | * kfifo_put - put data into the fifo |
323 | #undef __KFIFO_PUT | 370 | * @fifo: address of the fifo to be used |
324 | } | 371 | * @val: the data to be added |
372 | * | ||
373 | * This macro copies the given value into the fifo. | ||
374 | * It returns 0 if the fifo was full. Otherwise it returns the number | ||
375 | * processed elements. | ||
376 | * | ||
377 | * Note that with only one concurrent reader and one concurrent | ||
378 | * writer, you don't need extra locking to use these macro. | ||
379 | */ | ||
380 | #define kfifo_put(fifo, val) \ | ||
381 | ({ \ | ||
382 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
383 | typeof((val) + 1) __val = (val); \ | ||
384 | unsigned int __ret; \ | ||
385 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
386 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
387 | if (0) { \ | ||
388 | typeof(__tmp->ptr_const) __dummy __attribute__ ((unused)); \ | ||
389 | __dummy = (typeof(__val))NULL; \ | ||
390 | } \ | ||
391 | if (__recsize) \ | ||
392 | __ret = __kfifo_in_r(__kfifo, __val, sizeof(*__val), \ | ||
393 | __recsize); \ | ||
394 | else { \ | ||
395 | __ret = !kfifo_is_full(__tmp); \ | ||
396 | if (__ret) { \ | ||
397 | (__is_kfifo_ptr(__tmp) ? \ | ||
398 | ((typeof(__tmp->type))__kfifo->data) : \ | ||
399 | (__tmp->buf) \ | ||
400 | )[__kfifo->in & __tmp->kfifo.mask] = \ | ||
401 | *(typeof(__tmp->type))__val; \ | ||
402 | smp_wmb(); \ | ||
403 | __kfifo->in++; \ | ||
404 | } \ | ||
405 | } \ | ||
406 | __ret; \ | ||
407 | }) | ||
325 | 408 | ||
326 | /* | 409 | /** |
327 | * __kfifo_in_... internal functions for put date into the fifo | 410 | * kfifo_get - get data from the fifo |
328 | * do not call it directly, use kfifo_in_rec() instead | 411 | * @fifo: address of the fifo to be used |
329 | */ | 412 | * @val: the var where to store the data to be added |
330 | extern unsigned int __kfifo_in_n(struct kfifo *fifo, | 413 | * |
331 | const void *from, unsigned int n, unsigned int recsize); | 414 | * This macro reads the data from the fifo. |
415 | * It returns 0 if the fifo was empty. Otherwise it returns the number | ||
416 | * processed elements. | ||
417 | * | ||
418 | * Note that with only one concurrent reader and one concurrent | ||
419 | * writer, you don't need extra locking to use these macro. | ||
420 | */ | ||
421 | #define kfifo_get(fifo, val) \ | ||
422 | __kfifo_must_check_helper( \ | ||
423 | ({ \ | ||
424 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
425 | typeof((val) + 1) __val = (val); \ | ||
426 | unsigned int __ret; \ | ||
427 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
428 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
429 | if (0) \ | ||
430 | __val = (typeof(__tmp->ptr))0; \ | ||
431 | if (__recsize) \ | ||
432 | __ret = __kfifo_out_r(__kfifo, __val, sizeof(*__val), \ | ||
433 | __recsize); \ | ||
434 | else { \ | ||
435 | __ret = !kfifo_is_empty(__tmp); \ | ||
436 | if (__ret) { \ | ||
437 | *(typeof(__tmp->type))__val = \ | ||
438 | (__is_kfifo_ptr(__tmp) ? \ | ||
439 | ((typeof(__tmp->type))__kfifo->data) : \ | ||
440 | (__tmp->buf) \ | ||
441 | )[__kfifo->out & __tmp->kfifo.mask]; \ | ||
442 | smp_wmb(); \ | ||
443 | __kfifo->out++; \ | ||
444 | } \ | ||
445 | } \ | ||
446 | __ret; \ | ||
447 | }) \ | ||
448 | ) | ||
332 | 449 | ||
333 | extern unsigned int __kfifo_in_generic(struct kfifo *fifo, | 450 | /** |
334 | const void *from, unsigned int n, unsigned int recsize); | 451 | * kfifo_peek - get data from the fifo without removing |
452 | * @fifo: address of the fifo to be used | ||
453 | * @val: the var where to store the data to be added | ||
454 | * | ||
455 | * This reads the data from the fifo without removing it from the fifo. | ||
456 | * It returns 0 if the fifo was empty. Otherwise it returns the number | ||
457 | * processed elements. | ||
458 | * | ||
459 | * Note that with only one concurrent reader and one concurrent | ||
460 | * writer, you don't need extra locking to use these macro. | ||
461 | */ | ||
462 | #define kfifo_peek(fifo, val) \ | ||
463 | __kfifo_must_check_helper( \ | ||
464 | ({ \ | ||
465 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
466 | typeof((val) + 1) __val = (val); \ | ||
467 | unsigned int __ret; \ | ||
468 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
469 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
470 | if (0) \ | ||
471 | __val = (typeof(__tmp->ptr))NULL; \ | ||
472 | if (__recsize) \ | ||
473 | __ret = __kfifo_out_peek_r(__kfifo, __val, sizeof(*__val), \ | ||
474 | __recsize); \ | ||
475 | else { \ | ||
476 | __ret = !kfifo_is_empty(__tmp); \ | ||
477 | if (__ret) { \ | ||
478 | *(typeof(__tmp->type))__val = \ | ||
479 | (__is_kfifo_ptr(__tmp) ? \ | ||
480 | ((typeof(__tmp->type))__kfifo->data) : \ | ||
481 | (__tmp->buf) \ | ||
482 | )[__kfifo->out & __tmp->kfifo.mask]; \ | ||
483 | smp_wmb(); \ | ||
484 | } \ | ||
485 | } \ | ||
486 | __ret; \ | ||
487 | }) \ | ||
488 | ) | ||
335 | 489 | ||
336 | static inline unsigned int __kfifo_in_rec(struct kfifo *fifo, | 490 | /** |
337 | const void *from, unsigned int n, unsigned int recsize) | 491 | * kfifo_in - put data into the fifo |
338 | { | 492 | * @fifo: address of the fifo to be used |
339 | unsigned int ret; | 493 | * @buf: the data to be added |
494 | * @n: number of elements to be added | ||
495 | * | ||
496 | * This macro copies the given buffer into the fifo and returns the | ||
497 | * number of copied elements. | ||
498 | * | ||
499 | * Note that with only one concurrent reader and one concurrent | ||
500 | * writer, you don't need extra locking to use these macro. | ||
501 | */ | ||
502 | #define kfifo_in(fifo, buf, n) \ | ||
503 | ({ \ | ||
504 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
505 | typeof((buf) + 1) __buf = (buf); \ | ||
506 | unsigned long __n = (n); \ | ||
507 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
508 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
509 | if (0) { \ | ||
510 | typeof(__tmp->ptr_const) __dummy __attribute__ ((unused)); \ | ||
511 | __dummy = (typeof(__buf))NULL; \ | ||
512 | } \ | ||
513 | (__recsize) ?\ | ||
514 | __kfifo_in_r(__kfifo, __buf, __n, __recsize) : \ | ||
515 | __kfifo_in(__kfifo, __buf, __n); \ | ||
516 | }) | ||
340 | 517 | ||
341 | ret = __kfifo_in_n(fifo, from, n, recsize); | 518 | /** |
519 | * kfifo_in_spinlocked - put data into the fifo using a spinlock for locking | ||
520 | * @fifo: address of the fifo to be used | ||
521 | * @buf: the data to be added | ||
522 | * @n: number of elements to be added | ||
523 | * @lock: pointer to the spinlock to use for locking | ||
524 | * | ||
525 | * This macro copies the given values buffer into the fifo and returns the | ||
526 | * number of copied elements. | ||
527 | */ | ||
528 | #define kfifo_in_spinlocked(fifo, buf, n, lock) \ | ||
529 | ({ \ | ||
530 | unsigned long __flags; \ | ||
531 | unsigned int __ret; \ | ||
532 | spin_lock_irqsave(lock, __flags); \ | ||
533 | __ret = kfifo_in(fifo, buf, n); \ | ||
534 | spin_unlock_irqrestore(lock, __flags); \ | ||
535 | __ret; \ | ||
536 | }) | ||
537 | |||
538 | /* alias for kfifo_in_spinlocked, will be removed in a future release */ | ||
539 | #define kfifo_in_locked(fifo, buf, n, lock) \ | ||
540 | kfifo_in_spinlocked(fifo, buf, n, lock) | ||
342 | 541 | ||
343 | if (likely(ret == 0)) { | 542 | /** |
344 | if (recsize) | 543 | * kfifo_out - get data from the fifo |
345 | __kfifo_poke_n(fifo, recsize, n); | 544 | * @fifo: address of the fifo to be used |
346 | __kfifo_add_in(fifo, n + recsize); | 545 | * @buf: pointer to the storage buffer |
347 | } | 546 | * @n: max. number of elements to get |
348 | return ret; | 547 | * |
349 | } | 548 | * This macro get some data from the fifo and return the numbers of elements |
549 | * copied. | ||
550 | * | ||
551 | * Note that with only one concurrent reader and one concurrent | ||
552 | * writer, you don't need extra locking to use these macro. | ||
553 | */ | ||
554 | #define kfifo_out(fifo, buf, n) \ | ||
555 | __kfifo_must_check_helper( \ | ||
556 | ({ \ | ||
557 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
558 | typeof((buf) + 1) __buf = (buf); \ | ||
559 | unsigned long __n = (n); \ | ||
560 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
561 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
562 | if (0) { \ | ||
563 | typeof(__tmp->ptr) __dummy = NULL; \ | ||
564 | __buf = __dummy; \ | ||
565 | } \ | ||
566 | (__recsize) ?\ | ||
567 | __kfifo_out_r(__kfifo, __buf, __n, __recsize) : \ | ||
568 | __kfifo_out(__kfifo, __buf, __n); \ | ||
569 | }) \ | ||
570 | ) | ||
571 | |||
572 | /** | ||
573 | * kfifo_out_spinlocked - get data from the fifo using a spinlock for locking | ||
574 | * @fifo: address of the fifo to be used | ||
575 | * @buf: pointer to the storage buffer | ||
576 | * @n: max. number of elements to get | ||
577 | * @lock: pointer to the spinlock to use for locking | ||
578 | * | ||
579 | * This macro get the data from the fifo and return the numbers of elements | ||
580 | * copied. | ||
581 | */ | ||
582 | #define kfifo_out_spinlocked(fifo, buf, n, lock) \ | ||
583 | __kfifo_must_check_helper( \ | ||
584 | ({ \ | ||
585 | unsigned long __flags; \ | ||
586 | unsigned int __ret; \ | ||
587 | spin_lock_irqsave(lock, __flags); \ | ||
588 | __ret = kfifo_out(fifo, buf, n); \ | ||
589 | spin_unlock_irqrestore(lock, __flags); \ | ||
590 | __ret; \ | ||
591 | }) \ | ||
592 | ) | ||
593 | |||
594 | /* alias for kfifo_out_spinlocked, will be removed in a future release */ | ||
595 | #define kfifo_out_locked(fifo, buf, n, lock) \ | ||
596 | kfifo_out_spinlocked(fifo, buf, n, lock) | ||
350 | 597 | ||
351 | /** | 598 | /** |
352 | * kfifo_in_rec - puts some record data into the FIFO | 599 | * kfifo_from_user - puts some data from user space into the fifo |
353 | * @fifo: the fifo to be used. | 600 | * @fifo: address of the fifo to be used |
354 | * @from: the data to be added. | 601 | * @from: pointer to the data to be added |
355 | * @n: the length of the data to be added. | 602 | * @len: the length of the data to be added |
356 | * @recsize: size of record field | 603 | * @copied: pointer to output variable to store the number of copied bytes |
357 | * | 604 | * |
358 | * This function copies @n bytes from the @from into the FIFO and returns | 605 | * This macro copies at most @len bytes from the @from into the |
359 | * the number of bytes which cannot be copied. | 606 | * fifo, depending of the available space and returns -EFAULT/0. |
360 | * A returned value greater than the @n value means that the record doesn't | ||
361 | * fit into the buffer. | ||
362 | * | 607 | * |
363 | * Note that with only one concurrent reader and one concurrent | 608 | * Note that with only one concurrent reader and one concurrent |
364 | * writer, you don't need extra locking to use these functions. | 609 | * writer, you don't need extra locking to use these macro. |
365 | */ | 610 | */ |
366 | static inline __must_check unsigned int kfifo_in_rec(struct kfifo *fifo, | 611 | #define kfifo_from_user(fifo, from, len, copied) \ |
367 | void *from, unsigned int n, unsigned int recsize) | 612 | __kfifo_must_check_helper( \ |
368 | { | 613 | ({ \ |
369 | if (!__builtin_constant_p(recsize)) | 614 | typeof((fifo) + 1) __tmp = (fifo); \ |
370 | return __kfifo_in_generic(fifo, from, n, recsize); | 615 | const void __user *__from = (from); \ |
371 | return __kfifo_in_rec(fifo, from, n, recsize); | 616 | unsigned int __len = (len); \ |
372 | } | 617 | unsigned int *__copied = (copied); \ |
618 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
619 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
620 | (__recsize) ? \ | ||
621 | __kfifo_from_user_r(__kfifo, __from, __len, __copied, __recsize) : \ | ||
622 | __kfifo_from_user(__kfifo, __from, __len, __copied); \ | ||
623 | }) \ | ||
624 | ) | ||
373 | 625 | ||
374 | /* | 626 | /** |
375 | * __kfifo_out_... internal functions for get date from the fifo | 627 | * kfifo_to_user - copies data from the fifo into user space |
376 | * do not call it directly, use kfifo_out_rec() instead | 628 | * @fifo: address of the fifo to be used |
377 | */ | 629 | * @to: where the data must be copied |
378 | extern unsigned int __kfifo_out_n(struct kfifo *fifo, | 630 | * @len: the size of the destination buffer |
379 | void *to, unsigned int reclen, unsigned int recsize); | 631 | * @copied: pointer to output variable to store the number of copied bytes |
632 | * | ||
633 | * This macro copies at most @len bytes from the fifo into the | ||
634 | * @to buffer and returns -EFAULT/0. | ||
635 | * | ||
636 | * Note that with only one concurrent reader and one concurrent | ||
637 | * writer, you don't need extra locking to use these macro. | ||
638 | */ | ||
639 | #define kfifo_to_user(fifo, to, len, copied) \ | ||
640 | __kfifo_must_check_helper( \ | ||
641 | ({ \ | ||
642 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
643 | void __user *__to = (to); \ | ||
644 | unsigned int __len = (len); \ | ||
645 | unsigned int *__copied = (copied); \ | ||
646 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
647 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
648 | (__recsize) ? \ | ||
649 | __kfifo_to_user_r(__kfifo, __to, __len, __copied, __recsize) : \ | ||
650 | __kfifo_to_user(__kfifo, __to, __len, __copied); \ | ||
651 | }) \ | ||
652 | ) | ||
653 | |||
654 | /** | ||
655 | * kfifo_dma_in_prepare - setup a scatterlist for DMA input | ||
656 | * @fifo: address of the fifo to be used | ||
657 | * @sgl: pointer to the scatterlist array | ||
658 | * @nents: number of entries in the scatterlist array | ||
659 | * @len: number of elements to transfer | ||
660 | * | ||
661 | * This macro fills a scatterlist for DMA input. | ||
662 | * It returns the number entries in the scatterlist array. | ||
663 | * | ||
664 | * Note that with only one concurrent reader and one concurrent | ||
665 | * writer, you don't need extra locking to use these macros. | ||
666 | */ | ||
667 | #define kfifo_dma_in_prepare(fifo, sgl, nents, len) \ | ||
668 | ({ \ | ||
669 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
670 | struct scatterlist *__sgl = (sgl); \ | ||
671 | int __nents = (nents); \ | ||
672 | unsigned int __len = (len); \ | ||
673 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
674 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
675 | (__recsize) ? \ | ||
676 | __kfifo_dma_in_prepare_r(__kfifo, __sgl, __nents, __len, __recsize) : \ | ||
677 | __kfifo_dma_in_prepare(__kfifo, __sgl, __nents, __len); \ | ||
678 | }) | ||
380 | 679 | ||
381 | extern unsigned int __kfifo_out_generic(struct kfifo *fifo, | 680 | /** |
382 | void *to, unsigned int n, | 681 | * kfifo_dma_in_finish - finish a DMA IN operation |
383 | unsigned int recsize, unsigned int *total); | 682 | * @fifo: address of the fifo to be used |
683 | * @len: number of bytes to received | ||
684 | * | ||
685 | * This macro finish a DMA IN operation. The in counter will be updated by | ||
686 | * the len parameter. No error checking will be done. | ||
687 | * | ||
688 | * Note that with only one concurrent reader and one concurrent | ||
689 | * writer, you don't need extra locking to use these macros. | ||
690 | */ | ||
691 | #define kfifo_dma_in_finish(fifo, len) \ | ||
692 | (void)({ \ | ||
693 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
694 | unsigned int __len = (len); \ | ||
695 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
696 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
697 | if (__recsize) \ | ||
698 | __kfifo_dma_in_finish_r(__kfifo, __len, __recsize); \ | ||
699 | else \ | ||
700 | __kfifo->in += __len / sizeof(*__tmp->type); \ | ||
701 | }) | ||
384 | 702 | ||
385 | static inline unsigned int __kfifo_out_rec(struct kfifo *fifo, | 703 | /** |
386 | void *to, unsigned int n, unsigned int recsize, | 704 | * kfifo_dma_out_prepare - setup a scatterlist for DMA output |
387 | unsigned int *total) | 705 | * @fifo: address of the fifo to be used |
388 | { | 706 | * @sgl: pointer to the scatterlist array |
389 | unsigned int l; | 707 | * @nents: number of entries in the scatterlist array |
390 | 708 | * @len: number of elements to transfer | |
391 | if (!recsize) { | 709 | * |
392 | l = n; | 710 | * This macro fills a scatterlist for DMA output which at most @len bytes |
393 | if (total) | 711 | * to transfer. |
394 | *total = l; | 712 | * It returns the number entries in the scatterlist array. |
395 | } else { | 713 | * A zero means there is no space available and the scatterlist is not filled. |
396 | l = __kfifo_peek_n(fifo, recsize); | 714 | * |
397 | if (total) | 715 | * Note that with only one concurrent reader and one concurrent |
398 | *total = l; | 716 | * writer, you don't need extra locking to use these macros. |
399 | if (n < l) | 717 | */ |
400 | return l; | 718 | #define kfifo_dma_out_prepare(fifo, sgl, nents, len) \ |
401 | } | 719 | ({ \ |
720 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
721 | struct scatterlist *__sgl = (sgl); \ | ||
722 | int __nents = (nents); \ | ||
723 | unsigned int __len = (len); \ | ||
724 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
725 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
726 | (__recsize) ? \ | ||
727 | __kfifo_dma_out_prepare_r(__kfifo, __sgl, __nents, __len, __recsize) : \ | ||
728 | __kfifo_dma_out_prepare(__kfifo, __sgl, __nents, __len); \ | ||
729 | }) | ||
402 | 730 | ||
403 | return __kfifo_out_n(fifo, to, l, recsize); | 731 | /** |
404 | } | 732 | * kfifo_dma_out_finish - finish a DMA OUT operation |
733 | * @fifo: address of the fifo to be used | ||
734 | * @len: number of bytes transferd | ||
735 | * | ||
736 | * This macro finish a DMA OUT operation. The out counter will be updated by | ||
737 | * the len parameter. No error checking will be done. | ||
738 | * | ||
739 | * Note that with only one concurrent reader and one concurrent | ||
740 | * writer, you don't need extra locking to use these macros. | ||
741 | */ | ||
742 | #define kfifo_dma_out_finish(fifo, len) \ | ||
743 | (void)({ \ | ||
744 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
745 | unsigned int __len = (len); \ | ||
746 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
747 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
748 | if (__recsize) \ | ||
749 | __kfifo_dma_out_finish_r(__kfifo, __recsize); \ | ||
750 | else \ | ||
751 | __kfifo->out += __len / sizeof(*__tmp->type); \ | ||
752 | }) | ||
405 | 753 | ||
406 | /** | 754 | /** |
407 | * kfifo_out_rec - gets some record data from the FIFO | 755 | * kfifo_out_peek - gets some data from the fifo |
408 | * @fifo: the fifo to be used. | 756 | * @fifo: address of the fifo to be used |
409 | * @to: where the data must be copied. | 757 | * @buf: pointer to the storage buffer |
410 | * @n: the size of the destination buffer. | 758 | * @n: max. number of elements to get |
411 | * @recsize: size of record field | ||
412 | * @total: pointer where the total number of to copied bytes should stored | ||
413 | * | 759 | * |
414 | * This function copies at most @n bytes from the FIFO to @to and returns the | 760 | * This macro get the data from the fifo and return the numbers of elements |
415 | * number of bytes which cannot be copied. | 761 | * copied. The data is not removed from the fifo. |
416 | * A returned value greater than the @n value means that the record doesn't | ||
417 | * fit into the @to buffer. | ||
418 | * | 762 | * |
419 | * Note that with only one concurrent reader and one concurrent | 763 | * Note that with only one concurrent reader and one concurrent |
420 | * writer, you don't need extra locking to use these functions. | 764 | * writer, you don't need extra locking to use these macro. |
421 | */ | 765 | */ |
422 | static inline __must_check unsigned int kfifo_out_rec(struct kfifo *fifo, | 766 | #define kfifo_out_peek(fifo, buf, n) \ |
423 | void *to, unsigned int n, unsigned int recsize, | 767 | __kfifo_must_check_helper( \ |
424 | unsigned int *total) | 768 | ({ \ |
769 | typeof((fifo) + 1) __tmp = (fifo); \ | ||
770 | typeof((buf) + 1) __buf = (buf); \ | ||
771 | unsigned long __n = (n); \ | ||
772 | const size_t __recsize = sizeof(*__tmp->rectype); \ | ||
773 | struct __kfifo *__kfifo = &__tmp->kfifo; \ | ||
774 | if (0) { \ | ||
775 | typeof(__tmp->ptr) __dummy __attribute__ ((unused)) = NULL; \ | ||
776 | __buf = __dummy; \ | ||
777 | } \ | ||
778 | (__recsize) ? \ | ||
779 | __kfifo_out_peek_r(__kfifo, __buf, __n, __recsize) : \ | ||
780 | __kfifo_out_peek(__kfifo, __buf, __n); \ | ||
781 | }) \ | ||
782 | ) | ||
425 | 783 | ||
426 | { | 784 | extern int __kfifo_alloc(struct __kfifo *fifo, unsigned int size, |
427 | if (!__builtin_constant_p(recsize)) | 785 | size_t esize, gfp_t gfp_mask); |
428 | return __kfifo_out_generic(fifo, to, n, recsize, total); | ||
429 | return __kfifo_out_rec(fifo, to, n, recsize, total); | ||
430 | } | ||
431 | 786 | ||
432 | /* | 787 | extern void __kfifo_free(struct __kfifo *fifo); |
433 | * __kfifo_from_user_... internal functions for transfer from user space into | ||
434 | * the fifo. do not call it directly, use kfifo_from_user_rec() instead | ||
435 | */ | ||
436 | extern unsigned int __kfifo_from_user_n(struct kfifo *fifo, | ||
437 | const void __user *from, unsigned int n, unsigned int recsize); | ||
438 | 788 | ||
439 | extern unsigned int __kfifo_from_user_generic(struct kfifo *fifo, | 789 | extern int __kfifo_init(struct __kfifo *fifo, void *buffer, |
440 | const void __user *from, unsigned int n, unsigned int recsize); | 790 | unsigned int size, size_t esize); |
441 | 791 | ||
442 | static inline unsigned int __kfifo_from_user_rec(struct kfifo *fifo, | 792 | extern unsigned int __kfifo_in(struct __kfifo *fifo, |
443 | const void __user *from, unsigned int n, unsigned int recsize) | 793 | const void *buf, unsigned int len); |
444 | { | ||
445 | unsigned int ret; | ||
446 | 794 | ||
447 | ret = __kfifo_from_user_n(fifo, from, n, recsize); | 795 | extern unsigned int __kfifo_out(struct __kfifo *fifo, |
796 | void *buf, unsigned int len); | ||
448 | 797 | ||
449 | if (likely(ret == 0)) { | 798 | extern int __kfifo_from_user(struct __kfifo *fifo, |
450 | if (recsize) | 799 | const void __user *from, unsigned long len, unsigned int *copied); |
451 | __kfifo_poke_n(fifo, recsize, n); | ||
452 | __kfifo_add_in(fifo, n + recsize); | ||
453 | } | ||
454 | return ret; | ||
455 | } | ||
456 | 800 | ||
457 | /** | 801 | extern int __kfifo_to_user(struct __kfifo *fifo, |
458 | * kfifo_from_user_rec - puts some data from user space into the FIFO | 802 | void __user *to, unsigned long len, unsigned int *copied); |
459 | * @fifo: the fifo to be used. | ||
460 | * @from: pointer to the data to be added. | ||
461 | * @n: the length of the data to be added. | ||
462 | * @recsize: size of record field | ||
463 | * | ||
464 | * This function copies @n bytes from the @from into the | ||
465 | * FIFO and returns the number of bytes which cannot be copied. | ||
466 | * | ||
467 | * If the returned value is equal or less the @n value, the copy_from_user() | ||
468 | * functions has failed. Otherwise the record doesn't fit into the buffer. | ||
469 | * | ||
470 | * Note that with only one concurrent reader and one concurrent | ||
471 | * writer, you don't need extra locking to use these functions. | ||
472 | */ | ||
473 | static inline __must_check unsigned int kfifo_from_user_rec(struct kfifo *fifo, | ||
474 | const void __user *from, unsigned int n, unsigned int recsize) | ||
475 | { | ||
476 | if (!__builtin_constant_p(recsize)) | ||
477 | return __kfifo_from_user_generic(fifo, from, n, recsize); | ||
478 | return __kfifo_from_user_rec(fifo, from, n, recsize); | ||
479 | } | ||
480 | 803 | ||
481 | /* | 804 | extern unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo, |
482 | * __kfifo_to_user_... internal functions for transfer fifo data into user space | 805 | struct scatterlist *sgl, int nents, unsigned int len); |
483 | * do not call it directly, use kfifo_to_user_rec() instead | ||
484 | */ | ||
485 | extern unsigned int __kfifo_to_user_n(struct kfifo *fifo, | ||
486 | void __user *to, unsigned int n, unsigned int reclen, | ||
487 | unsigned int recsize); | ||
488 | 806 | ||
489 | extern unsigned int __kfifo_to_user_generic(struct kfifo *fifo, | 807 | extern unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo, |
490 | void __user *to, unsigned int n, unsigned int recsize, | 808 | struct scatterlist *sgl, int nents, unsigned int len); |
491 | unsigned int *total); | ||
492 | 809 | ||
493 | static inline unsigned int __kfifo_to_user_rec(struct kfifo *fifo, | 810 | extern unsigned int __kfifo_out_peek(struct __kfifo *fifo, |
494 | void __user *to, unsigned int n, | 811 | void *buf, unsigned int len); |
495 | unsigned int recsize, unsigned int *total) | ||
496 | { | ||
497 | unsigned int l; | ||
498 | |||
499 | if (!recsize) { | ||
500 | l = n; | ||
501 | if (total) | ||
502 | *total = l; | ||
503 | } else { | ||
504 | l = __kfifo_peek_n(fifo, recsize); | ||
505 | if (total) | ||
506 | *total = l; | ||
507 | if (n < l) | ||
508 | return l; | ||
509 | } | ||
510 | 812 | ||
511 | return __kfifo_to_user_n(fifo, to, n, l, recsize); | 813 | extern unsigned int __kfifo_in_r(struct __kfifo *fifo, |
512 | } | 814 | const void *buf, unsigned int len, size_t recsize); |
513 | 815 | ||
514 | /** | 816 | extern unsigned int __kfifo_out_r(struct __kfifo *fifo, |
515 | * kfifo_to_user_rec - gets data from the FIFO and write it to user space | 817 | void *buf, unsigned int len, size_t recsize); |
516 | * @fifo: the fifo to be used. | ||
517 | * @to: where the data must be copied. | ||
518 | * @n: the size of the destination buffer. | ||
519 | * @recsize: size of record field | ||
520 | * @total: pointer where the total number of to copied bytes should stored | ||
521 | * | ||
522 | * This function copies at most @n bytes from the FIFO to the @to. | ||
523 | * In case of an error, the function returns the number of bytes which cannot | ||
524 | * be copied. | ||
525 | * If the returned value is equal or less the @n value, the copy_to_user() | ||
526 | * functions has failed. Otherwise the record doesn't fit into the @to buffer. | ||
527 | * | ||
528 | * Note that with only one concurrent reader and one concurrent | ||
529 | * writer, you don't need extra locking to use these functions. | ||
530 | */ | ||
531 | static inline __must_check unsigned int kfifo_to_user_rec(struct kfifo *fifo, | ||
532 | void __user *to, unsigned int n, unsigned int recsize, | ||
533 | unsigned int *total) | ||
534 | { | ||
535 | if (!__builtin_constant_p(recsize)) | ||
536 | return __kfifo_to_user_generic(fifo, to, n, recsize, total); | ||
537 | return __kfifo_to_user_rec(fifo, to, n, recsize, total); | ||
538 | } | ||
539 | 818 | ||
540 | /* | 819 | extern int __kfifo_from_user_r(struct __kfifo *fifo, |
541 | * __kfifo_peek_... internal functions for peek into the next fifo record | 820 | const void __user *from, unsigned long len, unsigned int *copied, |
542 | * do not call it directly, use kfifo_peek_rec() instead | 821 | size_t recsize); |
543 | */ | ||
544 | extern unsigned int __kfifo_peek_generic(struct kfifo *fifo, | ||
545 | unsigned int recsize); | ||
546 | 822 | ||
547 | /** | 823 | extern int __kfifo_to_user_r(struct __kfifo *fifo, void __user *to, |
548 | * kfifo_peek_rec - gets the size of the next FIFO record data | 824 | unsigned long len, unsigned int *copied, size_t recsize); |
549 | * @fifo: the fifo to be used. | ||
550 | * @recsize: size of record field | ||
551 | * | ||
552 | * This function returns the size of the next FIFO record in number of bytes | ||
553 | */ | ||
554 | static inline __must_check unsigned int kfifo_peek_rec(struct kfifo *fifo, | ||
555 | unsigned int recsize) | ||
556 | { | ||
557 | if (!__builtin_constant_p(recsize)) | ||
558 | return __kfifo_peek_generic(fifo, recsize); | ||
559 | if (!recsize) | ||
560 | return kfifo_len(fifo); | ||
561 | return __kfifo_peek_n(fifo, recsize); | ||
562 | } | ||
563 | 825 | ||
564 | /* | 826 | extern unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo, |
565 | * __kfifo_skip_... internal functions for skip the next fifo record | 827 | struct scatterlist *sgl, int nents, unsigned int len, size_t recsize); |
566 | * do not call it directly, use kfifo_skip_rec() instead | ||
567 | */ | ||
568 | extern void __kfifo_skip_generic(struct kfifo *fifo, unsigned int recsize); | ||
569 | 828 | ||
570 | static inline void __kfifo_skip_rec(struct kfifo *fifo, | 829 | extern void __kfifo_dma_in_finish_r(struct __kfifo *fifo, |
571 | unsigned int recsize) | 830 | unsigned int len, size_t recsize); |
572 | { | ||
573 | unsigned int l; | ||
574 | 831 | ||
575 | if (recsize) { | 832 | extern unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo, |
576 | l = __kfifo_peek_n(fifo, recsize); | 833 | struct scatterlist *sgl, int nents, unsigned int len, size_t recsize); |
577 | 834 | ||
578 | if (l + recsize <= kfifo_len(fifo)) { | 835 | extern void __kfifo_dma_out_finish_r(struct __kfifo *fifo, size_t recsize); |
579 | __kfifo_add_out(fifo, l + recsize); | ||
580 | return; | ||
581 | } | ||
582 | } | ||
583 | kfifo_reset_out(fifo); | ||
584 | } | ||
585 | 836 | ||
586 | /** | 837 | extern unsigned int __kfifo_len_r(struct __kfifo *fifo, size_t recsize); |
587 | * kfifo_skip_rec - skip the next fifo out record | ||
588 | * @fifo: the fifo to be used. | ||
589 | * @recsize: size of record field | ||
590 | * | ||
591 | * This function skips the next FIFO record | ||
592 | */ | ||
593 | static inline void kfifo_skip_rec(struct kfifo *fifo, | ||
594 | unsigned int recsize) | ||
595 | { | ||
596 | if (!__builtin_constant_p(recsize)) | ||
597 | __kfifo_skip_generic(fifo, recsize); | ||
598 | else | ||
599 | __kfifo_skip_rec(fifo, recsize); | ||
600 | } | ||
601 | 838 | ||
602 | /** | 839 | extern void __kfifo_skip_r(struct __kfifo *fifo, size_t recsize); |
603 | * kfifo_avail_rec - returns the number of bytes available in a record FIFO | ||
604 | * @fifo: the fifo to be used. | ||
605 | * @recsize: size of record field | ||
606 | */ | ||
607 | static inline __must_check unsigned int kfifo_avail_rec(struct kfifo *fifo, | ||
608 | unsigned int recsize) | ||
609 | { | ||
610 | unsigned int l = kfifo_size(fifo) - kfifo_len(fifo); | ||
611 | 840 | ||
612 | return (l > recsize) ? l - recsize : 0; | 841 | extern unsigned int __kfifo_out_peek_r(struct __kfifo *fifo, |
613 | } | 842 | void *buf, unsigned int len, size_t recsize); |
843 | |||
844 | extern unsigned int __kfifo_max_r(unsigned int len, size_t recsize); | ||
614 | 845 | ||
615 | #endif | 846 | #endif |