Thomas Gleixner | 74ba920 | 2019-05-20 09:19:02 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 3 | * A generic kernel FIFO implementation |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 5 | * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | */ |
| 7 | |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 8 | #include <linux/dma-mapping.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | #include <linux/err.h> |
Andy Shevchenko | 22bcc91 | 2024-04-23 22:23:10 +0300 | [diff] [blame] | 10 | #include <linux/export.h> |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 11 | #include <linux/kfifo.h> |
Andy Shevchenko | 22bcc91 | 2024-04-23 22:23:10 +0300 | [diff] [blame] | 12 | #include <linux/log2.h> |
| 13 | #include <linux/scatterlist.h> |
| 14 | #include <linux/slab.h> |
| 15 | #include <linux/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 17 | /* |
| 18 | * internal helper to calculate the unused elements in a fifo |
| 19 | */ |
| 20 | static inline unsigned int kfifo_unused(struct __kfifo *fifo) |
Stefani Seibold | 4546548 | 2009-12-21 14:37:26 -0800 | [diff] [blame] | 21 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 22 | return (fifo->mask + 1) - (fifo->in - fifo->out); |
Stefani Seibold | 4546548 | 2009-12-21 14:37:26 -0800 | [diff] [blame] | 23 | } |
| 24 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 25 | int __kfifo_alloc(struct __kfifo *fifo, unsigned int size, |
| 26 | size_t esize, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | /* |
Martin Kelly | 75a24b8 | 2018-03-26 11:18:23 -0700 | [diff] [blame] | 29 | * round up to the next power of 2, since our 'let the indices |
Robert P. J. Day | b33112d | 2009-06-16 15:33:34 -0700 | [diff] [blame] | 30 | * wrap' technique works only in this case. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | */ |
Stefani Seibold | dfe2a77 | 2013-02-27 17:05:51 -0800 | [diff] [blame] | 32 | size = roundup_pow_of_two(size); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 33 | |
| 34 | fifo->in = 0; |
| 35 | fifo->out = 0; |
| 36 | fifo->esize = esize; |
| 37 | |
| 38 | if (size < 2) { |
| 39 | fifo->data = NULL; |
| 40 | fifo->mask = 0; |
| 41 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | } |
| 43 | |
Kees Cook | 6da2ec5 | 2018-06-12 13:55:00 -0700 | [diff] [blame] | 44 | fifo->data = kmalloc_array(esize, size, gfp_mask); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 45 | |
| 46 | if (!fifo->data) { |
| 47 | fifo->mask = 0; |
Stefani Seibold | 4546548 | 2009-12-21 14:37:26 -0800 | [diff] [blame] | 48 | return -ENOMEM; |
| 49 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 50 | fifo->mask = size - 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
Stefani Seibold | 4546548 | 2009-12-21 14:37:26 -0800 | [diff] [blame] | 52 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 54 | EXPORT_SYMBOL(__kfifo_alloc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 56 | void __kfifo_free(struct __kfifo *fifo) |
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 | kfree(fifo->data); |
| 59 | fifo->in = 0; |
| 60 | fifo->out = 0; |
| 61 | fifo->esize = 0; |
| 62 | fifo->data = NULL; |
| 63 | fifo->mask = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 65 | EXPORT_SYMBOL(__kfifo_free); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 67 | int __kfifo_init(struct __kfifo *fifo, void *buffer, |
| 68 | unsigned int size, size_t esize) |
Stefani Seibold | a121f24 | 2009-12-21 14:37:31 -0800 | [diff] [blame] | 69 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 70 | size /= esize; |
| 71 | |
Linus Torvalds | ab9bb63 | 2019-08-30 18:47:15 -0700 | [diff] [blame] | 72 | if (!is_power_of_2(size)) |
| 73 | size = rounddown_pow_of_two(size); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 74 | |
| 75 | fifo->in = 0; |
| 76 | fifo->out = 0; |
| 77 | fifo->esize = esize; |
| 78 | fifo->data = buffer; |
| 79 | |
| 80 | if (size < 2) { |
| 81 | fifo->mask = 0; |
| 82 | return -EINVAL; |
Stefani Seibold | a121f24 | 2009-12-21 14:37:31 -0800 | [diff] [blame] | 83 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 84 | fifo->mask = size - 1; |
Stefani Seibold | a121f24 | 2009-12-21 14:37:31 -0800 | [diff] [blame] | 85 | |
Andi Kleen | 64ce103 | 2010-01-15 17:01:15 -0800 | [diff] [blame] | 86 | return 0; |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 87 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 88 | EXPORT_SYMBOL(__kfifo_init); |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 89 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 90 | static void kfifo_copy_in(struct __kfifo *fifo, const void *src, |
| 91 | unsigned int len, unsigned int off) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 92 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 93 | unsigned int size = fifo->mask + 1; |
| 94 | unsigned int esize = fifo->esize; |
| 95 | unsigned int l; |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 96 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 97 | off &= fifo->mask; |
| 98 | if (esize != 1) { |
| 99 | off *= esize; |
| 100 | size *= esize; |
| 101 | len *= esize; |
| 102 | } |
| 103 | l = min(len, size - off); |
| 104 | |
| 105 | memcpy(fifo->data + off, src, l); |
| 106 | memcpy(fifo->data, src + l, len - l); |
| 107 | /* |
| 108 | * make sure that the data in the fifo is up to date before |
| 109 | * incrementing the fifo->in index counter |
| 110 | */ |
| 111 | smp_wmb(); |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 112 | } |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 113 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 114 | unsigned int __kfifo_in(struct __kfifo *fifo, |
| 115 | const void *buf, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 117 | unsigned int l; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 119 | l = kfifo_unused(fifo); |
| 120 | if (len > l) |
| 121 | len = l; |
| 122 | |
| 123 | kfifo_copy_in(fifo, buf, len, fifo->in); |
| 124 | fifo->in += len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | return len; |
| 126 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 127 | EXPORT_SYMBOL(__kfifo_in); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 129 | static void kfifo_copy_out(struct __kfifo *fifo, void *dst, |
| 130 | unsigned int len, unsigned int off) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 131 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 132 | unsigned int size = fifo->mask + 1; |
| 133 | unsigned int esize = fifo->esize; |
| 134 | unsigned int l; |
| 135 | |
| 136 | off &= fifo->mask; |
| 137 | if (esize != 1) { |
| 138 | off *= esize; |
| 139 | size *= esize; |
| 140 | len *= esize; |
| 141 | } |
| 142 | l = min(len, size - off); |
| 143 | |
| 144 | memcpy(dst, fifo->data + off, l); |
| 145 | memcpy(dst + l, fifo->data, len - l); |
| 146 | /* |
| 147 | * make sure that the data is copied before |
| 148 | * incrementing the fifo->out index counter |
| 149 | */ |
| 150 | smp_wmb(); |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 151 | } |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 152 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 153 | unsigned int __kfifo_out_peek(struct __kfifo *fifo, |
| 154 | void *buf, unsigned int len) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 155 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 156 | unsigned int l; |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 157 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 158 | l = fifo->in - fifo->out; |
| 159 | if (len > l) |
| 160 | len = l; |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 161 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 162 | kfifo_copy_out(fifo, buf, len, fifo->out); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | return len; |
| 164 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 165 | EXPORT_SYMBOL(__kfifo_out_peek); |
Stefani Seibold | a121f24 | 2009-12-21 14:37:31 -0800 | [diff] [blame] | 166 | |
Jiri Slaby (SUSE) | 4edd7e9 | 2024-04-05 08:08:14 +0200 | [diff] [blame] | 167 | unsigned int __kfifo_out_linear(struct __kfifo *fifo, |
| 168 | unsigned int *tail, unsigned int n) |
| 169 | { |
| 170 | unsigned int size = fifo->mask + 1; |
| 171 | unsigned int off = fifo->out & fifo->mask; |
| 172 | |
| 173 | if (tail) |
| 174 | *tail = off; |
| 175 | |
| 176 | return min3(n, fifo->in - fifo->out, size - off); |
| 177 | } |
| 178 | EXPORT_SYMBOL(__kfifo_out_linear); |
| 179 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 180 | unsigned int __kfifo_out(struct __kfifo *fifo, |
| 181 | void *buf, unsigned int len) |
Andi Kleen | a5b9e2c | 2010-01-15 17:01:16 -0800 | [diff] [blame] | 182 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 183 | len = __kfifo_out_peek(fifo, buf, len); |
| 184 | fifo->out += len; |
Andi Kleen | a5b9e2c | 2010-01-15 17:01:16 -0800 | [diff] [blame] | 185 | return len; |
| 186 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 187 | EXPORT_SYMBOL(__kfifo_out); |
Andi Kleen | a5b9e2c | 2010-01-15 17:01:16 -0800 | [diff] [blame] | 188 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 189 | static unsigned long kfifo_copy_from_user(struct __kfifo *fifo, |
| 190 | const void __user *from, unsigned int len, unsigned int off, |
| 191 | unsigned int *copied) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 192 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 193 | unsigned int size = fifo->mask + 1; |
| 194 | unsigned int esize = fifo->esize; |
| 195 | unsigned int l; |
| 196 | unsigned long ret; |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 197 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 198 | off &= fifo->mask; |
| 199 | if (esize != 1) { |
| 200 | off *= esize; |
| 201 | size *= esize; |
| 202 | len *= esize; |
| 203 | } |
| 204 | l = min(len, size - off); |
Andi Kleen | 64ce103 | 2010-01-15 17:01:15 -0800 | [diff] [blame] | 205 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 206 | ret = copy_from_user(fifo->data + off, from, l); |
| 207 | if (unlikely(ret)) |
| 208 | ret = DIV_ROUND_UP(ret + len - l, esize); |
| 209 | else { |
| 210 | ret = copy_from_user(fifo->data, from + l, len - l); |
| 211 | if (unlikely(ret)) |
| 212 | ret = DIV_ROUND_UP(ret, esize); |
| 213 | } |
| 214 | /* |
| 215 | * make sure that the data in the fifo is up to date before |
| 216 | * incrementing the fifo->in index counter |
| 217 | */ |
| 218 | smp_wmb(); |
Lars-Peter Clausen | a019e48 | 2013-11-14 14:32:16 -0800 | [diff] [blame] | 219 | *copied = len - ret * esize; |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 220 | /* return the number of elements which are not copied */ |
Andi Kleen | 64ce103 | 2010-01-15 17:01:15 -0800 | [diff] [blame] | 221 | return ret; |
Stefani Seibold | a121f24 | 2009-12-21 14:37:31 -0800 | [diff] [blame] | 222 | } |
Stefani Seibold | a121f24 | 2009-12-21 14:37:31 -0800 | [diff] [blame] | 223 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 224 | int __kfifo_from_user(struct __kfifo *fifo, const void __user *from, |
| 225 | unsigned long len, unsigned int *copied) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 226 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 227 | unsigned int l; |
| 228 | unsigned long ret; |
| 229 | unsigned int esize = fifo->esize; |
| 230 | int err; |
| 231 | |
| 232 | if (esize != 1) |
| 233 | len /= esize; |
| 234 | |
| 235 | l = kfifo_unused(fifo); |
| 236 | if (len > l) |
| 237 | len = l; |
| 238 | |
| 239 | ret = kfifo_copy_from_user(fifo, from, len, fifo->in, copied); |
| 240 | if (unlikely(ret)) { |
| 241 | len -= ret; |
| 242 | err = -EFAULT; |
| 243 | } else |
| 244 | err = 0; |
| 245 | fifo->in += len; |
| 246 | return err; |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 247 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 248 | EXPORT_SYMBOL(__kfifo_from_user); |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 249 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 250 | static unsigned long kfifo_copy_to_user(struct __kfifo *fifo, void __user *to, |
| 251 | unsigned int len, unsigned int off, unsigned int *copied) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 252 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 253 | unsigned int l; |
| 254 | unsigned long ret; |
| 255 | unsigned int size = fifo->mask + 1; |
| 256 | unsigned int esize = fifo->esize; |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 257 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 258 | off &= fifo->mask; |
| 259 | if (esize != 1) { |
| 260 | off *= esize; |
| 261 | size *= esize; |
| 262 | len *= esize; |
| 263 | } |
| 264 | l = min(len, size - off); |
| 265 | |
| 266 | ret = copy_to_user(to, fifo->data + off, l); |
| 267 | if (unlikely(ret)) |
| 268 | ret = DIV_ROUND_UP(ret + len - l, esize); |
| 269 | else { |
| 270 | ret = copy_to_user(to + l, fifo->data, len - l); |
| 271 | if (unlikely(ret)) |
| 272 | ret = DIV_ROUND_UP(ret, esize); |
| 273 | } |
| 274 | /* |
| 275 | * make sure that the data is copied before |
| 276 | * incrementing the fifo->out index counter |
| 277 | */ |
| 278 | smp_wmb(); |
Lars-Peter Clausen | a019e48 | 2013-11-14 14:32:16 -0800 | [diff] [blame] | 279 | *copied = len - ret * esize; |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 280 | /* return the number of elements which are not copied */ |
| 281 | return ret; |
| 282 | } |
| 283 | |
| 284 | int __kfifo_to_user(struct __kfifo *fifo, void __user *to, |
| 285 | unsigned long len, unsigned int *copied) |
| 286 | { |
| 287 | unsigned int l; |
| 288 | unsigned long ret; |
| 289 | unsigned int esize = fifo->esize; |
| 290 | int err; |
| 291 | |
| 292 | if (esize != 1) |
| 293 | len /= esize; |
| 294 | |
| 295 | l = fifo->in - fifo->out; |
| 296 | if (len > l) |
| 297 | len = l; |
| 298 | ret = kfifo_copy_to_user(fifo, to, len, fifo->out, copied); |
| 299 | if (unlikely(ret)) { |
| 300 | len -= ret; |
| 301 | err = -EFAULT; |
| 302 | } else |
| 303 | err = 0; |
| 304 | fifo->out += len; |
| 305 | return err; |
| 306 | } |
| 307 | EXPORT_SYMBOL(__kfifo_to_user); |
| 308 | |
Jiri Slaby (SUSE) | fea0dde | 2024-04-05 08:08:17 +0200 | [diff] [blame] | 309 | static unsigned int setup_sgl_buf(struct __kfifo *fifo, struct scatterlist *sgl, |
| 310 | unsigned int data_offset, int nents, |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 311 | unsigned int len, dma_addr_t dma) |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 312 | { |
Jiri Slaby (SUSE) | fea0dde | 2024-04-05 08:08:17 +0200 | [diff] [blame] | 313 | const void *buf = fifo->data + data_offset; |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 314 | |
Jiri Slaby (SUSE) | e9d9576 | 2024-04-05 08:08:15 +0200 | [diff] [blame] | 315 | if (!nents || !len) |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 316 | return 0; |
| 317 | |
Jiri Slaby (SUSE) | e9d9576 | 2024-04-05 08:08:15 +0200 | [diff] [blame] | 318 | sg_set_buf(sgl, buf, len); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 319 | |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 320 | if (dma != DMA_MAPPING_ERROR) { |
| 321 | sg_dma_address(sgl) = dma + data_offset; |
| 322 | sg_dma_len(sgl) = len; |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 323 | } |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 324 | |
Jiri Slaby (SUSE) | e9d9576 | 2024-04-05 08:08:15 +0200 | [diff] [blame] | 325 | return 1; |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 326 | } |
| 327 | |
| 328 | static unsigned int setup_sgl(struct __kfifo *fifo, struct scatterlist *sgl, |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 329 | int nents, unsigned int len, unsigned int off, dma_addr_t dma) |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 330 | { |
| 331 | unsigned int size = fifo->mask + 1; |
| 332 | unsigned int esize = fifo->esize; |
Jiri Slaby (SUSE) | ed6d22f | 2024-04-05 08:08:16 +0200 | [diff] [blame] | 333 | unsigned int len_to_end; |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 334 | unsigned int n; |
| 335 | |
| 336 | off &= fifo->mask; |
| 337 | if (esize != 1) { |
| 338 | off *= esize; |
| 339 | size *= esize; |
| 340 | len *= esize; |
| 341 | } |
Jiri Slaby (SUSE) | ed6d22f | 2024-04-05 08:08:16 +0200 | [diff] [blame] | 342 | len_to_end = min(len, size - off); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 343 | |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 344 | n = setup_sgl_buf(fifo, sgl, off, nents, len_to_end, dma); |
| 345 | n += setup_sgl_buf(fifo, sgl + n, 0, nents - n, len - len_to_end, dma); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 346 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 347 | return n; |
| 348 | } |
| 349 | |
| 350 | unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo, |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 351 | struct scatterlist *sgl, int nents, unsigned int len, |
| 352 | dma_addr_t dma) |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 353 | { |
| 354 | unsigned int l; |
| 355 | |
| 356 | l = kfifo_unused(fifo); |
| 357 | if (len > l) |
| 358 | len = l; |
| 359 | |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 360 | return setup_sgl(fifo, sgl, nents, len, fifo->in, dma); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 361 | } |
| 362 | EXPORT_SYMBOL(__kfifo_dma_in_prepare); |
| 363 | |
| 364 | unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo, |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 365 | struct scatterlist *sgl, int nents, unsigned int len, |
| 366 | dma_addr_t dma) |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 367 | { |
| 368 | unsigned int l; |
| 369 | |
| 370 | l = fifo->in - fifo->out; |
| 371 | if (len > l) |
| 372 | len = l; |
| 373 | |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 374 | return setup_sgl(fifo, sgl, nents, len, fifo->out, dma); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 375 | } |
| 376 | EXPORT_SYMBOL(__kfifo_dma_out_prepare); |
| 377 | |
| 378 | unsigned int __kfifo_max_r(unsigned int len, size_t recsize) |
| 379 | { |
| 380 | unsigned int max = (1 << (recsize << 3)) - 1; |
| 381 | |
| 382 | if (len > max) |
| 383 | return max; |
| 384 | return len; |
| 385 | } |
Srinivas Kandagatla | 30059d9 | 2012-04-11 05:01:56 -0300 | [diff] [blame] | 386 | EXPORT_SYMBOL(__kfifo_max_r); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 387 | |
| 388 | #define __KFIFO_PEEK(data, out, mask) \ |
| 389 | ((data)[(out) & (mask)]) |
| 390 | /* |
| 391 | * __kfifo_peek_n internal helper function for determinate the length of |
| 392 | * the next record in the fifo |
| 393 | */ |
| 394 | static unsigned int __kfifo_peek_n(struct __kfifo *fifo, size_t recsize) |
| 395 | { |
| 396 | unsigned int l; |
| 397 | unsigned int mask = fifo->mask; |
| 398 | unsigned char *data = fifo->data; |
| 399 | |
| 400 | l = __KFIFO_PEEK(data, fifo->out, mask); |
| 401 | |
| 402 | if (--recsize) |
| 403 | l |= __KFIFO_PEEK(data, fifo->out + 1, mask) << 8; |
| 404 | |
| 405 | return l; |
| 406 | } |
| 407 | |
| 408 | #define __KFIFO_POKE(data, in, mask, val) \ |
| 409 | ( \ |
| 410 | (data)[(in) & (mask)] = (unsigned char)(val) \ |
| 411 | ) |
| 412 | |
| 413 | /* |
Zhen Lei | 9dbbc3b | 2021-07-07 18:07:31 -0700 | [diff] [blame] | 414 | * __kfifo_poke_n internal helper function for storing the length of |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 415 | * the record into the fifo |
| 416 | */ |
| 417 | static void __kfifo_poke_n(struct __kfifo *fifo, unsigned int n, size_t recsize) |
| 418 | { |
| 419 | unsigned int mask = fifo->mask; |
| 420 | unsigned char *data = fifo->data; |
| 421 | |
| 422 | __KFIFO_POKE(data, fifo->in, mask, n); |
| 423 | |
| 424 | if (recsize > 1) |
| 425 | __KFIFO_POKE(data, fifo->in + 1, mask, n >> 8); |
| 426 | } |
| 427 | |
| 428 | unsigned int __kfifo_len_r(struct __kfifo *fifo, size_t recsize) |
| 429 | { |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 430 | return __kfifo_peek_n(fifo, recsize); |
| 431 | } |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 432 | EXPORT_SYMBOL(__kfifo_len_r); |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 433 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 434 | unsigned int __kfifo_in_r(struct __kfifo *fifo, const void *buf, |
| 435 | unsigned int len, size_t recsize) |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 436 | { |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 437 | if (len + recsize > kfifo_unused(fifo)) |
| 438 | return 0; |
Stefani Seibold | 86d4880 | 2009-12-21 14:37:32 -0800 | [diff] [blame] | 439 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 440 | __kfifo_poke_n(fifo, len, recsize); |
| 441 | |
| 442 | kfifo_copy_in(fifo, buf, len, fifo->in + recsize); |
| 443 | fifo->in += len + recsize; |
| 444 | return len; |
| 445 | } |
| 446 | EXPORT_SYMBOL(__kfifo_in_r); |
| 447 | |
| 448 | static unsigned int kfifo_out_copy_r(struct __kfifo *fifo, |
| 449 | void *buf, unsigned int len, size_t recsize, unsigned int *n) |
| 450 | { |
| 451 | *n = __kfifo_peek_n(fifo, recsize); |
| 452 | |
| 453 | if (len > *n) |
| 454 | len = *n; |
| 455 | |
| 456 | kfifo_copy_out(fifo, buf, len, fifo->out + recsize); |
| 457 | return len; |
| 458 | } |
| 459 | |
| 460 | unsigned int __kfifo_out_peek_r(struct __kfifo *fifo, void *buf, |
| 461 | unsigned int len, size_t recsize) |
| 462 | { |
| 463 | unsigned int n; |
| 464 | |
| 465 | if (fifo->in == fifo->out) |
| 466 | return 0; |
| 467 | |
| 468 | return kfifo_out_copy_r(fifo, buf, len, recsize, &n); |
| 469 | } |
| 470 | EXPORT_SYMBOL(__kfifo_out_peek_r); |
| 471 | |
Jiri Slaby (SUSE) | 4edd7e9 | 2024-04-05 08:08:14 +0200 | [diff] [blame] | 472 | unsigned int __kfifo_out_linear_r(struct __kfifo *fifo, |
| 473 | unsigned int *tail, unsigned int n, size_t recsize) |
| 474 | { |
| 475 | if (fifo->in == fifo->out) |
| 476 | return 0; |
| 477 | |
| 478 | if (tail) |
| 479 | *tail = fifo->out + recsize; |
| 480 | |
| 481 | return min(n, __kfifo_peek_n(fifo, recsize)); |
| 482 | } |
| 483 | EXPORT_SYMBOL(__kfifo_out_linear_r); |
| 484 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 485 | unsigned int __kfifo_out_r(struct __kfifo *fifo, void *buf, |
| 486 | unsigned int len, size_t recsize) |
| 487 | { |
| 488 | unsigned int n; |
| 489 | |
| 490 | if (fifo->in == fifo->out) |
| 491 | return 0; |
| 492 | |
| 493 | len = kfifo_out_copy_r(fifo, buf, len, recsize, &n); |
| 494 | fifo->out += n + recsize; |
| 495 | return len; |
| 496 | } |
| 497 | EXPORT_SYMBOL(__kfifo_out_r); |
| 498 | |
Andrea Righi | b35de43 | 2010-08-19 14:13:27 -0700 | [diff] [blame] | 499 | void __kfifo_skip_r(struct __kfifo *fifo, size_t recsize) |
| 500 | { |
| 501 | unsigned int n; |
| 502 | |
| 503 | n = __kfifo_peek_n(fifo, recsize); |
| 504 | fifo->out += n + recsize; |
| 505 | } |
| 506 | EXPORT_SYMBOL(__kfifo_skip_r); |
| 507 | |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 508 | int __kfifo_from_user_r(struct __kfifo *fifo, const void __user *from, |
| 509 | unsigned long len, unsigned int *copied, size_t recsize) |
| 510 | { |
| 511 | unsigned long ret; |
| 512 | |
| 513 | len = __kfifo_max_r(len, recsize); |
| 514 | |
| 515 | if (len + recsize > kfifo_unused(fifo)) { |
| 516 | *copied = 0; |
| 517 | return 0; |
| 518 | } |
| 519 | |
| 520 | __kfifo_poke_n(fifo, len, recsize); |
| 521 | |
| 522 | ret = kfifo_copy_from_user(fifo, from, len, fifo->in + recsize, copied); |
| 523 | if (unlikely(ret)) { |
| 524 | *copied = 0; |
| 525 | return -EFAULT; |
| 526 | } |
| 527 | fifo->in += len + recsize; |
| 528 | return 0; |
| 529 | } |
| 530 | EXPORT_SYMBOL(__kfifo_from_user_r); |
| 531 | |
| 532 | int __kfifo_to_user_r(struct __kfifo *fifo, void __user *to, |
| 533 | unsigned long len, unsigned int *copied, size_t recsize) |
| 534 | { |
| 535 | unsigned long ret; |
| 536 | unsigned int n; |
| 537 | |
| 538 | if (fifo->in == fifo->out) { |
| 539 | *copied = 0; |
| 540 | return 0; |
| 541 | } |
| 542 | |
| 543 | n = __kfifo_peek_n(fifo, recsize); |
| 544 | if (len > n) |
| 545 | len = n; |
| 546 | |
| 547 | ret = kfifo_copy_to_user(fifo, to, len, fifo->out + recsize, copied); |
| 548 | if (unlikely(ret)) { |
| 549 | *copied = 0; |
| 550 | return -EFAULT; |
| 551 | } |
| 552 | fifo->out += n + recsize; |
| 553 | return 0; |
| 554 | } |
| 555 | EXPORT_SYMBOL(__kfifo_to_user_r); |
| 556 | |
| 557 | unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo, |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 558 | struct scatterlist *sgl, int nents, unsigned int len, size_t recsize, |
| 559 | dma_addr_t dma) |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 560 | { |
Himangi Saraogi | 89b3ac6 | 2014-08-08 14:22:44 -0700 | [diff] [blame] | 561 | BUG_ON(!nents); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 562 | |
| 563 | len = __kfifo_max_r(len, recsize); |
| 564 | |
| 565 | if (len + recsize > kfifo_unused(fifo)) |
| 566 | return 0; |
| 567 | |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 568 | return setup_sgl(fifo, sgl, nents, len, fifo->in + recsize, dma); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 569 | } |
| 570 | EXPORT_SYMBOL(__kfifo_dma_in_prepare_r); |
| 571 | |
| 572 | void __kfifo_dma_in_finish_r(struct __kfifo *fifo, |
| 573 | unsigned int len, size_t recsize) |
| 574 | { |
| 575 | len = __kfifo_max_r(len, recsize); |
| 576 | __kfifo_poke_n(fifo, len, recsize); |
| 577 | fifo->in += len + recsize; |
| 578 | } |
| 579 | EXPORT_SYMBOL(__kfifo_dma_in_finish_r); |
| 580 | |
| 581 | unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo, |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 582 | struct scatterlist *sgl, int nents, unsigned int len, size_t recsize, |
| 583 | dma_addr_t dma) |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 584 | { |
Himangi Saraogi | 89b3ac6 | 2014-08-08 14:22:44 -0700 | [diff] [blame] | 585 | BUG_ON(!nents); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 586 | |
| 587 | len = __kfifo_max_r(len, recsize); |
| 588 | |
| 589 | if (len + recsize > fifo->in - fifo->out) |
| 590 | return 0; |
| 591 | |
Jiri Slaby (SUSE) | d52b761 | 2024-04-05 08:08:18 +0200 | [diff] [blame] | 592 | return setup_sgl(fifo, sgl, nents, len, fifo->out + recsize, dma); |
Stefani Seibold | 2e956fb | 2010-08-10 18:03:38 -0700 | [diff] [blame] | 593 | } |
| 594 | EXPORT_SYMBOL(__kfifo_dma_out_prepare_r); |
| 595 | |