Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 2 | * A generic kernel FIFO implementation |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 4 | * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 19 | * |
| 20 | */ |
Stefani Seibold | 7acd72e | 2009-12-21 14:37:28 -0800 | [diff] [blame] | 21 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 22 | #ifndef _LINUX_KFIFO_H |
| 23 | #define _LINUX_KFIFO_H |
| 24 | |
Stefani Seibold | 7acd72e | 2009-12-21 14:37:28 -0800 | [diff] [blame] | 25 | /* |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 26 | * How to porting drivers to the new generic FIFO API: |
Stefani Seibold | 7acd72e | 2009-12-21 14:37:28 -0800 | [diff] [blame] | 27 | * |
| 28 | * - Modify the declaration of the "struct kfifo *" object into a |
| 29 | * in-place "struct kfifo" object |
| 30 | * - Init the in-place object with kfifo_alloc() or kfifo_init() |
| 31 | * Note: The address of the in-place "struct kfifo" object must be |
| 32 | * passed as the first argument to this functions |
| 33 | * - Replace the use of __kfifo_put into kfifo_in and __kfifo_get |
| 34 | * into kfifo_out |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 35 | * - Replace the use of kfifo_put into kfifo_in_spinlocked and kfifo_get |
| 36 | * into kfifo_out_spinlocked |
Stefani Seibold | 7acd72e | 2009-12-21 14:37:28 -0800 | [diff] [blame] | 37 | * Note: the spinlock pointer formerly passed to kfifo_init/kfifo_alloc |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 38 | * must be passed now to the kfifo_in_spinlocked and kfifo_out_spinlocked |
| 39 | * as the last parameter |
| 40 | * - The formerly __kfifo_* functions are renamed into kfifo_* |
Stefani Seibold | 7acd72e | 2009-12-21 14:37:28 -0800 | [diff] [blame] | 41 | */ |
| 42 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 43 | /* |
| 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 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | #include <linux/kernel.h> |
| 54 | #include <linux/spinlock.h> |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 55 | #include <linux/stddef.h> |
| 56 | #include <linux/scatterlist.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 58 | struct __kfifo { |
| 59 | unsigned int in; |
| 60 | unsigned int out; |
| 61 | unsigned int mask; |
| 62 | unsigned int esize; |
| 63 | void *data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | }; |
| 65 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 66 | #define __STRUCT_KFIFO_COMMON(datatype, recsize, ptrtype) \ |
| 67 | union { \ |
| 68 | struct __kfifo kfifo; \ |
| 69 | datatype *type; \ |
| 70 | char (*rectype)[recsize]; \ |
| 71 | ptrtype *ptr; \ |
| 72 | const ptrtype *ptr_const; \ |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 73 | } |
| 74 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 75 | #define __STRUCT_KFIFO(type, size, recsize, ptrtype) \ |
| 76 | { \ |
| 77 | __STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \ |
| 78 | type buf[((size < 2) || (size & (size - 1))) ? -1 : size]; \ |
| 79 | } |
| 80 | |
| 81 | #define STRUCT_KFIFO(type, size) \ |
| 82 | struct __STRUCT_KFIFO(type, size, 0, type) |
| 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 |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 95 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 96 | struct kfifo __STRUCT_KFIFO_PTR(unsigned char, 0, void); |
| 97 | |
| 98 | #define STRUCT_KFIFO_REC_1(size) \ |
| 99 | struct __STRUCT_KFIFO(unsigned char, size, 1, void) |
| 100 | |
| 101 | #define STRUCT_KFIFO_REC_2(size) \ |
| 102 | struct __STRUCT_KFIFO(unsigned char, size, 2, void) |
| 103 | |
| 104 | /* |
| 105 | * define kfifo_rec types |
| 106 | */ |
| 107 | struct kfifo_rec_ptr_1 __STRUCT_KFIFO_PTR(unsigned char, 1, void); |
| 108 | struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void); |
| 109 | |
| 110 | /* |
| 111 | * helper macro to distinguish between real in place fifo where the fifo |
| 112 | * array is a part of the structure and the fifo type where the array is |
| 113 | * outside of the fifo structure. |
| 114 | */ |
| 115 | #define __is_kfifo_ptr(fifo) (sizeof(*fifo) == sizeof(struct __kfifo)) |
| 116 | |
| 117 | /** |
| 118 | * DECLARE_KFIFO_PTR - macro to declare a fifo pointer object |
| 119 | * @fifo: name of the declared fifo |
| 120 | * @type: type of the fifo elements |
| 121 | */ |
| 122 | #define DECLARE_KFIFO_PTR(fifo, type) STRUCT_KFIFO_PTR(type) fifo |
| 123 | |
| 124 | /** |
| 125 | * DECLARE_KFIFO - macro to declare a fifo object |
| 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 |
| 129 | */ |
| 130 | #define DECLARE_KFIFO(fifo, type, size) STRUCT_KFIFO(type, size) fifo |
| 131 | |
| 132 | /** |
| 133 | * INIT_KFIFO - Initialize a fifo declared by DECLARE_KFIFO |
| 134 | * @fifo: name of the declared fifo datatype |
| 135 | */ |
| 136 | #define INIT_KFIFO(fifo) \ |
| 137 | (void)({ \ |
| 138 | typeof(&(fifo)) __tmp = &(fifo); \ |
| 139 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 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 | }) |
| 146 | |
| 147 | /** |
| 148 | * DEFINE_KFIFO - macro to define and initialize a fifo |
| 149 | * @fifo: name of the declared fifo datatype |
| 150 | * @type: type of the fifo elements |
| 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 | |
Andrew Morton | 52c5171 | 2010-10-26 14:21:19 -0700 | [diff] [blame] | 174 | /* __kfifo_must_check_helper() is temporarily disabled because it was faulty */ |
| 175 | #define __kfifo_must_check_helper(x) (x) |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 176 | |
| 177 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 178 | * kfifo_initialized - Check if the fifo is initialized |
| 179 | * @fifo: address of the fifo to check |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 180 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 181 | * Return %true if fifo is initialized, otherwise %false. |
Andi Kleen | d994ffc | 2010-01-15 17:01:17 -0800 | [diff] [blame] | 182 | * Assumes the fifo was 0 before. |
| 183 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 184 | #define kfifo_initialized(fifo) ((fifo)->kfifo.mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | |
| 186 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 187 | * kfifo_esize - returns the size of the element managed by the fifo |
| 188 | * @fifo: address of the fifo to be used |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 190 | #define kfifo_esize(fifo) ((fifo)->kfifo.esize) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | |
| 192 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 193 | * kfifo_recsize - returns the size of the record length field |
| 194 | * @fifo: address of the fifo to be used |
Stefani Seibold | a121f24 | 2009-12-21 14:37:31 -0800 | [diff] [blame] | 195 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 196 | #define kfifo_recsize(fifo) (sizeof(*(fifo)->rectype)) |
Stefani Seibold | a121f24 | 2009-12-21 14:37:31 -0800 | [diff] [blame] | 197 | |
| 198 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 199 | * kfifo_size - returns the size of the fifo in elements |
| 200 | * @fifo: address of the fifo to be used |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 201 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 202 | #define kfifo_size(fifo) ((fifo)->kfifo.mask + 1) |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 203 | |
| 204 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 205 | * kfifo_reset - removes the entire fifo content |
| 206 | * @fifo: address of the fifo to be used |
| 207 | * |
| 208 | * Note: usage of kfifo_reset() is dangerous. It should be only called when the |
| 209 | * fifo is exclusived locked or when it is secured that no other thread is |
| 210 | * accessing the fifo. |
Stefani Seibold | c1e13f2 | 2009-12-21 14:37:27 -0800 | [diff] [blame] | 211 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 212 | #define kfifo_reset(fifo) \ |
| 213 | (void)({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 214 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 215 | __tmp->kfifo.in = __tmp->kfifo.out = 0; \ |
| 216 | }) |
Stefani Seibold | c1e13f2 | 2009-12-21 14:37:27 -0800 | [diff] [blame] | 217 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 218 | /** |
| 219 | * kfifo_reset_out - skip fifo content |
| 220 | * @fifo: address of the fifo to be used |
| 221 | * |
| 222 | * Note: The usage of kfifo_reset_out() is safe until it will be only called |
| 223 | * from the reader thread and there is only one concurrent reader. Otherwise |
| 224 | * it is dangerous and must be handled in the same way as kfifo_reset(). |
| 225 | */ |
| 226 | #define kfifo_reset_out(fifo) \ |
| 227 | (void)({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 228 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 229 | __tmp->kfifo.out = __tmp->kfifo.in; \ |
| 230 | }) |
| 231 | |
| 232 | /** |
| 233 | * kfifo_len - returns the number of used elements in the fifo |
| 234 | * @fifo: address of the fifo to be used |
| 235 | */ |
| 236 | #define kfifo_len(fifo) \ |
| 237 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 238 | typeof((fifo) + 1) __tmpl = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 239 | __tmpl->kfifo.in - __tmpl->kfifo.out; \ |
| 240 | }) |
Stefani Seibold | c1e13f2 | 2009-12-21 14:37:27 -0800 | [diff] [blame] | 241 | |
| 242 | /** |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 243 | * kfifo_is_empty - returns true if the fifo is empty |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 244 | * @fifo: address of the fifo to be used |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 245 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 246 | #define kfifo_is_empty(fifo) \ |
| 247 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 248 | typeof((fifo) + 1) __tmpq = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 249 | __tmpq->kfifo.in == __tmpq->kfifo.out; \ |
| 250 | }) |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 251 | |
| 252 | /** |
| 253 | * kfifo_is_full - returns true if the fifo is full |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 254 | * @fifo: address of the fifo to be used |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 255 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 256 | #define kfifo_is_full(fifo) \ |
| 257 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 258 | typeof((fifo) + 1) __tmpq = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 259 | kfifo_len(__tmpq) > __tmpq->kfifo.mask; \ |
| 260 | }) |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 261 | |
| 262 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 263 | * kfifo_avail - returns the number of unused elements in the fifo |
| 264 | * @fifo: address of the fifo to be used |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 265 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 266 | #define kfifo_avail(fifo) \ |
| 267 | __kfifo_must_check_helper( \ |
| 268 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 269 | typeof((fifo) + 1) __tmpq = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 270 | const size_t __recsize = sizeof(*__tmpq->rectype); \ |
| 271 | unsigned int __avail = kfifo_size(__tmpq) - kfifo_len(__tmpq); \ |
| 272 | (__recsize) ? ((__avail <= __recsize) ? 0 : \ |
| 273 | __kfifo_max_r(__avail - __recsize, __recsize)) : \ |
| 274 | __avail; \ |
| 275 | }) \ |
| 276 | ) |
Stefani Seibold | 37bdfbb | 2009-12-21 14:37:30 -0800 | [diff] [blame] | 277 | |
| 278 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 279 | * kfifo_skip - skip output data |
| 280 | * @fifo: address of the fifo to be used |
| 281 | */ |
| 282 | #define kfifo_skip(fifo) \ |
| 283 | (void)({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 284 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 285 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 286 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 287 | if (__recsize) \ |
| 288 | __kfifo_skip_r(__kfifo, __recsize); \ |
| 289 | else \ |
| 290 | __kfifo->out++; \ |
| 291 | }) |
| 292 | |
| 293 | /** |
| 294 | * kfifo_peek_len - gets the size of the next fifo record |
| 295 | * @fifo: address of the fifo to be used |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 297 | * This function returns the size of the next fifo record in number of bytes. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 299 | #define kfifo_peek_len(fifo) \ |
| 300 | __kfifo_must_check_helper( \ |
| 301 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 302 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 303 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 304 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 305 | (!__recsize) ? kfifo_len(__tmp) * sizeof(*__tmp->type) : \ |
| 306 | __kfifo_len_r(__kfifo, __recsize); \ |
| 307 | }) \ |
| 308 | ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | |
| 310 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 311 | * kfifo_alloc - dynamically allocates a new fifo buffer |
| 312 | * @fifo: pointer to the fifo |
| 313 | * @size: the number of elements in the fifo, this must be a power of 2 |
| 314 | * @gfp_mask: get_free_pages mask, passed to kmalloc() |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 315 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 316 | * This macro dynamically allocates a new fifo buffer. |
| 317 | * |
| 318 | * The numer of elements will be rounded-up to a power of 2. |
| 319 | * The fifo will be release with kfifo_free(). |
| 320 | * Return 0 if no error, otherwise an error code. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 322 | #define kfifo_alloc(fifo, size, gfp_mask) \ |
| 323 | __kfifo_must_check_helper( \ |
| 324 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 325 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 326 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 327 | __is_kfifo_ptr(__tmp) ? \ |
| 328 | __kfifo_alloc(__kfifo, size, sizeof(*__tmp->type), gfp_mask) : \ |
| 329 | -EINVAL; \ |
| 330 | }) \ |
| 331 | ) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 332 | |
| 333 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 334 | * kfifo_free - frees the fifo |
| 335 | * @fifo: the fifo to be freed |
| 336 | */ |
| 337 | #define kfifo_free(fifo) \ |
| 338 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 339 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 340 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 341 | if (__is_kfifo_ptr(__tmp)) \ |
| 342 | __kfifo_free(__kfifo); \ |
| 343 | }) |
| 344 | |
| 345 | /** |
| 346 | * kfifo_init - initialize a fifo using a preallocated buffer |
| 347 | * @fifo: the fifo to assign the buffer |
| 348 | * @buffer: the preallocated buffer to be used |
| 349 | * @size: the size of the internal buffer, this have to be a power of 2 |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 350 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 351 | * This macro initialize a fifo using a preallocated buffer. |
| 352 | * |
| 353 | * The numer of elements will be rounded-up to a power of 2. |
| 354 | * Return 0 if no error, otherwise an error code. |
| 355 | */ |
| 356 | #define kfifo_init(fifo, buffer, size) \ |
| 357 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 358 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 359 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 360 | __is_kfifo_ptr(__tmp) ? \ |
| 361 | __kfifo_init(__kfifo, buffer, size, sizeof(*__tmp->type)) : \ |
| 362 | -EINVAL; \ |
| 363 | }) |
| 364 | |
| 365 | /** |
| 366 | * kfifo_put - put data into the fifo |
| 367 | * @fifo: address of the fifo to be used |
| 368 | * @val: the data to be added |
| 369 | * |
| 370 | * This macro copies the given value into the fifo. |
| 371 | * It returns 0 if the fifo was full. Otherwise it returns the number |
| 372 | * processed elements. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 373 | * |
| 374 | * Note that with only one concurrent reader and one concurrent |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 375 | * writer, you don't need extra locking to use these macro. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 376 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 377 | #define kfifo_put(fifo, val) \ |
| 378 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 379 | typeof((fifo) + 1) __tmp = (fifo); \ |
| 380 | typeof((val) + 1) __val = (val); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 381 | unsigned int __ret; \ |
| 382 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 383 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 384 | if (0) { \ |
| 385 | typeof(__tmp->ptr_const) __dummy __attribute__ ((unused)); \ |
| 386 | __dummy = (typeof(__val))NULL; \ |
| 387 | } \ |
| 388 | if (__recsize) \ |
| 389 | __ret = __kfifo_in_r(__kfifo, __val, sizeof(*__val), \ |
| 390 | __recsize); \ |
| 391 | else { \ |
| 392 | __ret = !kfifo_is_full(__tmp); \ |
| 393 | if (__ret) { \ |
| 394 | (__is_kfifo_ptr(__tmp) ? \ |
| 395 | ((typeof(__tmp->type))__kfifo->data) : \ |
| 396 | (__tmp->buf) \ |
| 397 | )[__kfifo->in & __tmp->kfifo.mask] = \ |
| 398 | *(typeof(__tmp->type))__val; \ |
| 399 | smp_wmb(); \ |
| 400 | __kfifo->in++; \ |
| 401 | } \ |
| 402 | } \ |
| 403 | __ret; \ |
| 404 | }) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 405 | |
| 406 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 407 | * kfifo_get - get data from the fifo |
| 408 | * @fifo: address of the fifo to be used |
| 409 | * @val: the var where to store the data to be added |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 410 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 411 | * This macro reads the data from the fifo. |
| 412 | * It returns 0 if the fifo was empty. Otherwise it returns the number |
| 413 | * processed elements. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 414 | * |
| 415 | * Note that with only one concurrent reader and one concurrent |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 416 | * writer, you don't need extra locking to use these macro. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 417 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 418 | #define kfifo_get(fifo, val) \ |
| 419 | __kfifo_must_check_helper( \ |
| 420 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 421 | typeof((fifo) + 1) __tmp = (fifo); \ |
| 422 | typeof((val) + 1) __val = (val); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 423 | unsigned int __ret; \ |
| 424 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 425 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 426 | if (0) \ |
| 427 | __val = (typeof(__tmp->ptr))0; \ |
| 428 | if (__recsize) \ |
| 429 | __ret = __kfifo_out_r(__kfifo, __val, sizeof(*__val), \ |
| 430 | __recsize); \ |
| 431 | else { \ |
| 432 | __ret = !kfifo_is_empty(__tmp); \ |
| 433 | if (__ret) { \ |
| 434 | *(typeof(__tmp->type))__val = \ |
| 435 | (__is_kfifo_ptr(__tmp) ? \ |
| 436 | ((typeof(__tmp->type))__kfifo->data) : \ |
| 437 | (__tmp->buf) \ |
| 438 | )[__kfifo->out & __tmp->kfifo.mask]; \ |
| 439 | smp_wmb(); \ |
| 440 | __kfifo->out++; \ |
| 441 | } \ |
| 442 | } \ |
| 443 | __ret; \ |
| 444 | }) \ |
| 445 | ) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 446 | |
| 447 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 448 | * kfifo_peek - get data from the fifo without removing |
| 449 | * @fifo: address of the fifo to be used |
| 450 | * @val: the var where to store the data to be added |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 451 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 452 | * This reads the data from the fifo without removing it from the fifo. |
| 453 | * It returns 0 if the fifo was empty. Otherwise it returns the number |
| 454 | * processed elements. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 455 | * |
| 456 | * Note that with only one concurrent reader and one concurrent |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 457 | * writer, you don't need extra locking to use these macro. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 458 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 459 | #define kfifo_peek(fifo, val) \ |
| 460 | __kfifo_must_check_helper( \ |
| 461 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 462 | typeof((fifo) + 1) __tmp = (fifo); \ |
| 463 | typeof((val) + 1) __val = (val); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 464 | unsigned int __ret; \ |
| 465 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 466 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 467 | if (0) \ |
| 468 | __val = (typeof(__tmp->ptr))NULL; \ |
| 469 | if (__recsize) \ |
| 470 | __ret = __kfifo_out_peek_r(__kfifo, __val, sizeof(*__val), \ |
| 471 | __recsize); \ |
| 472 | else { \ |
| 473 | __ret = !kfifo_is_empty(__tmp); \ |
| 474 | if (__ret) { \ |
| 475 | *(typeof(__tmp->type))__val = \ |
| 476 | (__is_kfifo_ptr(__tmp) ? \ |
| 477 | ((typeof(__tmp->type))__kfifo->data) : \ |
| 478 | (__tmp->buf) \ |
| 479 | )[__kfifo->out & __tmp->kfifo.mask]; \ |
| 480 | smp_wmb(); \ |
| 481 | } \ |
| 482 | } \ |
| 483 | __ret; \ |
| 484 | }) \ |
| 485 | ) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 486 | |
| 487 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 488 | * kfifo_in - put data into the fifo |
| 489 | * @fifo: address of the fifo to be used |
| 490 | * @buf: the data to be added |
| 491 | * @n: number of elements to be added |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 492 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 493 | * This macro copies the given buffer into the fifo and returns the |
| 494 | * number of copied elements. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 495 | * |
| 496 | * Note that with only one concurrent reader and one concurrent |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 497 | * writer, you don't need extra locking to use these macro. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 498 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 499 | #define kfifo_in(fifo, buf, n) \ |
| 500 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 501 | typeof((fifo) + 1) __tmp = (fifo); \ |
| 502 | typeof((buf) + 1) __buf = (buf); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 503 | unsigned long __n = (n); \ |
| 504 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 505 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 506 | if (0) { \ |
| 507 | typeof(__tmp->ptr_const) __dummy __attribute__ ((unused)); \ |
| 508 | __dummy = (typeof(__buf))NULL; \ |
| 509 | } \ |
| 510 | (__recsize) ?\ |
| 511 | __kfifo_in_r(__kfifo, __buf, __n, __recsize) : \ |
| 512 | __kfifo_in(__kfifo, __buf, __n); \ |
| 513 | }) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 514 | |
| 515 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 516 | * kfifo_in_spinlocked - put data into the fifo using a spinlock for locking |
| 517 | * @fifo: address of the fifo to be used |
| 518 | * @buf: the data to be added |
| 519 | * @n: number of elements to be added |
| 520 | * @lock: pointer to the spinlock to use for locking |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 521 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 522 | * This macro copies the given values buffer into the fifo and returns the |
| 523 | * number of copied elements. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 524 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 525 | #define kfifo_in_spinlocked(fifo, buf, n, lock) \ |
| 526 | ({ \ |
| 527 | unsigned long __flags; \ |
| 528 | unsigned int __ret; \ |
| 529 | spin_lock_irqsave(lock, __flags); \ |
| 530 | __ret = kfifo_in(fifo, buf, n); \ |
| 531 | spin_unlock_irqrestore(lock, __flags); \ |
| 532 | __ret; \ |
| 533 | }) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 534 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 535 | /* alias for kfifo_in_spinlocked, will be removed in a future release */ |
| 536 | #define kfifo_in_locked(fifo, buf, n, lock) \ |
| 537 | kfifo_in_spinlocked(fifo, buf, n, lock) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 538 | |
| 539 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 540 | * kfifo_out - get data from the fifo |
| 541 | * @fifo: address of the fifo to be used |
| 542 | * @buf: pointer to the storage buffer |
| 543 | * @n: max. number of elements to get |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 544 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 545 | * This macro get some data from the fifo and return the numbers of elements |
| 546 | * copied. |
| 547 | * |
| 548 | * Note that with only one concurrent reader and one concurrent |
| 549 | * writer, you don't need extra locking to use these macro. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 550 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 551 | #define kfifo_out(fifo, buf, n) \ |
| 552 | __kfifo_must_check_helper( \ |
| 553 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 554 | typeof((fifo) + 1) __tmp = (fifo); \ |
| 555 | typeof((buf) + 1) __buf = (buf); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 556 | unsigned long __n = (n); \ |
| 557 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 558 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 559 | if (0) { \ |
| 560 | typeof(__tmp->ptr) __dummy = NULL; \ |
| 561 | __buf = __dummy; \ |
| 562 | } \ |
| 563 | (__recsize) ?\ |
| 564 | __kfifo_out_r(__kfifo, __buf, __n, __recsize) : \ |
| 565 | __kfifo_out(__kfifo, __buf, __n); \ |
| 566 | }) \ |
| 567 | ) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 568 | |
| 569 | /** |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 570 | * kfifo_out_spinlocked - get data from the fifo using a spinlock for locking |
| 571 | * @fifo: address of the fifo to be used |
| 572 | * @buf: pointer to the storage buffer |
| 573 | * @n: max. number of elements to get |
| 574 | * @lock: pointer to the spinlock to use for locking |
| 575 | * |
| 576 | * This macro get the data from the fifo and return the numbers of elements |
| 577 | * copied. |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 578 | */ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 579 | #define kfifo_out_spinlocked(fifo, buf, n, lock) \ |
| 580 | __kfifo_must_check_helper( \ |
| 581 | ({ \ |
| 582 | unsigned long __flags; \ |
| 583 | unsigned int __ret; \ |
| 584 | spin_lock_irqsave(lock, __flags); \ |
| 585 | __ret = kfifo_out(fifo, buf, n); \ |
| 586 | spin_unlock_irqrestore(lock, __flags); \ |
| 587 | __ret; \ |
| 588 | }) \ |
| 589 | ) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 590 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 591 | /* alias for kfifo_out_spinlocked, will be removed in a future release */ |
| 592 | #define kfifo_out_locked(fifo, buf, n, lock) \ |
| 593 | kfifo_out_spinlocked(fifo, buf, n, lock) |
| 594 | |
| 595 | /** |
| 596 | * kfifo_from_user - puts some data from user space into the fifo |
| 597 | * @fifo: address of the fifo to be used |
| 598 | * @from: pointer to the data to be added |
| 599 | * @len: the length of the data to be added |
| 600 | * @copied: pointer to output variable to store the number of copied bytes |
| 601 | * |
| 602 | * This macro copies at most @len bytes from the @from into the |
| 603 | * fifo, depending of the available space and returns -EFAULT/0. |
| 604 | * |
| 605 | * Note that with only one concurrent reader and one concurrent |
| 606 | * writer, you don't need extra locking to use these macro. |
| 607 | */ |
| 608 | #define kfifo_from_user(fifo, from, len, copied) \ |
| 609 | __kfifo_must_check_helper( \ |
| 610 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 611 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 612 | const void __user *__from = (from); \ |
| 613 | unsigned int __len = (len); \ |
| 614 | unsigned int *__copied = (copied); \ |
| 615 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 616 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 617 | (__recsize) ? \ |
| 618 | __kfifo_from_user_r(__kfifo, __from, __len, __copied, __recsize) : \ |
| 619 | __kfifo_from_user(__kfifo, __from, __len, __copied); \ |
| 620 | }) \ |
| 621 | ) |
| 622 | |
| 623 | /** |
| 624 | * kfifo_to_user - copies data from the fifo into user space |
| 625 | * @fifo: address of the fifo to be used |
| 626 | * @to: where the data must be copied |
| 627 | * @len: the size of the destination buffer |
| 628 | * @copied: pointer to output variable to store the number of copied bytes |
| 629 | * |
| 630 | * This macro copies at most @len bytes from the fifo into the |
| 631 | * @to buffer and returns -EFAULT/0. |
| 632 | * |
| 633 | * Note that with only one concurrent reader and one concurrent |
| 634 | * writer, you don't need extra locking to use these macro. |
| 635 | */ |
| 636 | #define kfifo_to_user(fifo, to, len, copied) \ |
| 637 | __kfifo_must_check_helper( \ |
| 638 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 639 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 640 | void __user *__to = (to); \ |
| 641 | unsigned int __len = (len); \ |
| 642 | unsigned int *__copied = (copied); \ |
| 643 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 644 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 645 | (__recsize) ? \ |
| 646 | __kfifo_to_user_r(__kfifo, __to, __len, __copied, __recsize) : \ |
| 647 | __kfifo_to_user(__kfifo, __to, __len, __copied); \ |
| 648 | }) \ |
| 649 | ) |
| 650 | |
| 651 | /** |
| 652 | * kfifo_dma_in_prepare - setup a scatterlist for DMA input |
| 653 | * @fifo: address of the fifo to be used |
| 654 | * @sgl: pointer to the scatterlist array |
| 655 | * @nents: number of entries in the scatterlist array |
| 656 | * @len: number of elements to transfer |
| 657 | * |
| 658 | * This macro fills a scatterlist for DMA input. |
| 659 | * It returns the number entries in the scatterlist array. |
| 660 | * |
| 661 | * Note that with only one concurrent reader and one concurrent |
| 662 | * writer, you don't need extra locking to use these macros. |
| 663 | */ |
| 664 | #define kfifo_dma_in_prepare(fifo, sgl, nents, len) \ |
| 665 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 666 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 667 | struct scatterlist *__sgl = (sgl); \ |
| 668 | int __nents = (nents); \ |
| 669 | unsigned int __len = (len); \ |
| 670 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 671 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 672 | (__recsize) ? \ |
| 673 | __kfifo_dma_in_prepare_r(__kfifo, __sgl, __nents, __len, __recsize) : \ |
| 674 | __kfifo_dma_in_prepare(__kfifo, __sgl, __nents, __len); \ |
| 675 | }) |
| 676 | |
| 677 | /** |
| 678 | * kfifo_dma_in_finish - finish a DMA IN operation |
| 679 | * @fifo: address of the fifo to be used |
| 680 | * @len: number of bytes to received |
| 681 | * |
| 682 | * This macro finish a DMA IN operation. The in counter will be updated by |
| 683 | * the len parameter. No error checking will be done. |
| 684 | * |
| 685 | * Note that with only one concurrent reader and one concurrent |
| 686 | * writer, you don't need extra locking to use these macros. |
| 687 | */ |
| 688 | #define kfifo_dma_in_finish(fifo, len) \ |
| 689 | (void)({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 690 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 691 | unsigned int __len = (len); \ |
| 692 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 693 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 694 | if (__recsize) \ |
| 695 | __kfifo_dma_in_finish_r(__kfifo, __len, __recsize); \ |
| 696 | else \ |
| 697 | __kfifo->in += __len / sizeof(*__tmp->type); \ |
| 698 | }) |
| 699 | |
| 700 | /** |
| 701 | * kfifo_dma_out_prepare - setup a scatterlist for DMA output |
| 702 | * @fifo: address of the fifo to be used |
| 703 | * @sgl: pointer to the scatterlist array |
| 704 | * @nents: number of entries in the scatterlist array |
| 705 | * @len: number of elements to transfer |
| 706 | * |
| 707 | * This macro fills a scatterlist for DMA output which at most @len bytes |
| 708 | * to transfer. |
| 709 | * It returns the number entries in the scatterlist array. |
| 710 | * A zero means there is no space available and the scatterlist is not filled. |
| 711 | * |
| 712 | * Note that with only one concurrent reader and one concurrent |
| 713 | * writer, you don't need extra locking to use these macros. |
| 714 | */ |
| 715 | #define kfifo_dma_out_prepare(fifo, sgl, nents, len) \ |
| 716 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 717 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 718 | struct scatterlist *__sgl = (sgl); \ |
| 719 | int __nents = (nents); \ |
| 720 | unsigned int __len = (len); \ |
| 721 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 722 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 723 | (__recsize) ? \ |
| 724 | __kfifo_dma_out_prepare_r(__kfifo, __sgl, __nents, __len, __recsize) : \ |
| 725 | __kfifo_dma_out_prepare(__kfifo, __sgl, __nents, __len); \ |
| 726 | }) |
| 727 | |
| 728 | /** |
| 729 | * kfifo_dma_out_finish - finish a DMA OUT operation |
| 730 | * @fifo: address of the fifo to be used |
| 731 | * @len: number of bytes transferd |
| 732 | * |
| 733 | * This macro finish a DMA OUT operation. The out counter will be updated by |
| 734 | * the len parameter. No error checking will be done. |
| 735 | * |
| 736 | * Note that with only one concurrent reader and one concurrent |
| 737 | * writer, you don't need extra locking to use these macros. |
| 738 | */ |
| 739 | #define kfifo_dma_out_finish(fifo, len) \ |
| 740 | (void)({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 741 | typeof((fifo) + 1) __tmp = (fifo); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 742 | unsigned int __len = (len); \ |
| 743 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 744 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 745 | if (__recsize) \ |
| 746 | __kfifo_dma_out_finish_r(__kfifo, __recsize); \ |
| 747 | else \ |
| 748 | __kfifo->out += __len / sizeof(*__tmp->type); \ |
| 749 | }) |
| 750 | |
| 751 | /** |
| 752 | * kfifo_out_peek - gets some data from the fifo |
| 753 | * @fifo: address of the fifo to be used |
| 754 | * @buf: pointer to the storage buffer |
| 755 | * @n: max. number of elements to get |
| 756 | * |
| 757 | * This macro get the data from the fifo and return the numbers of elements |
| 758 | * copied. The data is not removed from the fifo. |
| 759 | * |
| 760 | * Note that with only one concurrent reader and one concurrent |
| 761 | * writer, you don't need extra locking to use these macro. |
| 762 | */ |
| 763 | #define kfifo_out_peek(fifo, buf, n) \ |
| 764 | __kfifo_must_check_helper( \ |
| 765 | ({ \ |
Huang Ying | e0bf1024 | 2010-09-09 16:37:26 -0700 | [diff] [blame] | 766 | typeof((fifo) + 1) __tmp = (fifo); \ |
| 767 | typeof((buf) + 1) __buf = (buf); \ |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 768 | unsigned long __n = (n); \ |
| 769 | const size_t __recsize = sizeof(*__tmp->rectype); \ |
| 770 | struct __kfifo *__kfifo = &__tmp->kfifo; \ |
| 771 | if (0) { \ |
| 772 | typeof(__tmp->ptr) __dummy __attribute__ ((unused)) = NULL; \ |
| 773 | __buf = __dummy; \ |
| 774 | } \ |
| 775 | (__recsize) ? \ |
| 776 | __kfifo_out_peek_r(__kfifo, __buf, __n, __recsize) : \ |
| 777 | __kfifo_out_peek(__kfifo, __buf, __n); \ |
| 778 | }) \ |
| 779 | ) |
| 780 | |
| 781 | extern int __kfifo_alloc(struct __kfifo *fifo, unsigned int size, |
| 782 | size_t esize, gfp_t gfp_mask); |
| 783 | |
| 784 | extern void __kfifo_free(struct __kfifo *fifo); |
| 785 | |
| 786 | extern int __kfifo_init(struct __kfifo *fifo, void *buffer, |
| 787 | unsigned int size, size_t esize); |
| 788 | |
| 789 | extern unsigned int __kfifo_in(struct __kfifo *fifo, |
| 790 | const void *buf, unsigned int len); |
| 791 | |
| 792 | extern unsigned int __kfifo_out(struct __kfifo *fifo, |
| 793 | void *buf, unsigned int len); |
| 794 | |
| 795 | extern int __kfifo_from_user(struct __kfifo *fifo, |
| 796 | const void __user *from, unsigned long len, unsigned int *copied); |
| 797 | |
| 798 | extern int __kfifo_to_user(struct __kfifo *fifo, |
| 799 | void __user *to, unsigned long len, unsigned int *copied); |
| 800 | |
| 801 | extern unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo, |
| 802 | struct scatterlist *sgl, int nents, unsigned int len); |
| 803 | |
| 804 | extern unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo, |
| 805 | struct scatterlist *sgl, int nents, unsigned int len); |
| 806 | |
| 807 | extern unsigned int __kfifo_out_peek(struct __kfifo *fifo, |
| 808 | void *buf, unsigned int len); |
| 809 | |
| 810 | extern unsigned int __kfifo_in_r(struct __kfifo *fifo, |
| 811 | const void *buf, unsigned int len, size_t recsize); |
| 812 | |
| 813 | extern unsigned int __kfifo_out_r(struct __kfifo *fifo, |
| 814 | void *buf, unsigned int len, size_t recsize); |
| 815 | |
| 816 | extern int __kfifo_from_user_r(struct __kfifo *fifo, |
| 817 | const void __user *from, unsigned long len, unsigned int *copied, |
| 818 | size_t recsize); |
| 819 | |
| 820 | extern int __kfifo_to_user_r(struct __kfifo *fifo, void __user *to, |
| 821 | unsigned long len, unsigned int *copied, size_t recsize); |
| 822 | |
| 823 | extern unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo, |
| 824 | struct scatterlist *sgl, int nents, unsigned int len, size_t recsize); |
| 825 | |
| 826 | extern void __kfifo_dma_in_finish_r(struct __kfifo *fifo, |
| 827 | unsigned int len, size_t recsize); |
| 828 | |
| 829 | extern unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo, |
| 830 | struct scatterlist *sgl, int nents, unsigned int len, size_t recsize); |
| 831 | |
| 832 | extern void __kfifo_dma_out_finish_r(struct __kfifo *fifo, size_t recsize); |
| 833 | |
| 834 | extern unsigned int __kfifo_len_r(struct __kfifo *fifo, size_t recsize); |
| 835 | |
Andrea Righi | b35de43 | 2010-08-19 14:13:27 -0700 | [diff] [blame] | 836 | extern void __kfifo_skip_r(struct __kfifo *fifo, size_t recsize); |
| 837 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 838 | extern unsigned int __kfifo_out_peek_r(struct __kfifo *fifo, |
| 839 | void *buf, unsigned int len, size_t recsize); |
| 840 | |
| 841 | extern unsigned int __kfifo_max_r(unsigned int len, size_t recsize); |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 842 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 843 | #endif |