Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Loopback bridge driver for the Greybus loopback module. |
| 3 | * |
| 4 | * Copyright 2014 Google Inc. |
| 5 | * Copyright 2014 Linaro Ltd. |
| 6 | * |
| 7 | * Released under the GPLv2 only. |
| 8 | */ |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/module.h> |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 11 | #include <linux/mutex.h> |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 12 | #include <linux/slab.h> |
| 13 | #include <linux/kthread.h> |
| 14 | #include <linux/delay.h> |
| 15 | #include <linux/random.h> |
Greg Kroah-Hartman | 5679f78 | 2015-03-31 23:01:45 +0200 | [diff] [blame] | 16 | #include <linux/sizes.h> |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 17 | #include <linux/cdev.h> |
| 18 | #include <linux/fs.h> |
| 19 | #include <linux/kfifo.h> |
| 20 | |
Johan Hovold | 1ffc12b | 2015-04-16 09:53:59 +0200 | [diff] [blame] | 21 | #include <asm/div64.h> |
| 22 | |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 23 | #include "greybus.h" |
| 24 | |
Bryan O'Donoghue | fd489e1 | 2015-08-11 13:50:54 +0100 | [diff] [blame^] | 25 | #define NSEC_PER_DAY 86400000000000ULL |
| 26 | |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 27 | struct gb_loopback_stats { |
Alex Elder | e051c82 | 2015-08-03 12:57:14 -0500 | [diff] [blame] | 28 | u32 min; |
| 29 | u32 max; |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 30 | u64 sum; |
Alex Elder | e13fc28 | 2015-08-03 12:57:15 -0500 | [diff] [blame] | 31 | u32 count; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 32 | }; |
| 33 | |
| 34 | struct gb_loopback { |
| 35 | struct gb_connection *connection; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 36 | |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 37 | struct kfifo kfifo; |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 38 | struct mutex mutex; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 39 | struct task_struct *task; |
Bryan O'Donoghue | 3dfe8aa | 2015-07-24 10:02:56 +0100 | [diff] [blame] | 40 | wait_queue_head_t wq; |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 41 | dev_t dev; |
| 42 | struct cdev cdev; |
| 43 | struct device *device; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 44 | |
| 45 | int type; |
| 46 | u32 size; |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 47 | u32 iteration_max; |
| 48 | u32 iteration_count; |
Bryan O'Donoghue | e51eafe | 2015-07-14 00:53:13 +0100 | [diff] [blame] | 49 | size_t size_max; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 50 | int ms_wait; |
| 51 | |
| 52 | struct gb_loopback_stats latency; |
| 53 | struct gb_loopback_stats throughput; |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 54 | struct gb_loopback_stats requests_per_second; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 55 | u64 elapsed_nsecs; |
| 56 | u32 error; |
| 57 | }; |
| 58 | |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 59 | #define GB_LOOPBACK_FIFO_DEFAULT 8192 |
| 60 | |
| 61 | static struct class *loopback_class; |
| 62 | static int loopback_major; |
| 63 | static const struct file_operations loopback_fops; |
| 64 | static DEFINE_IDA(minors); |
| 65 | static unsigned kfifo_depth = GB_LOOPBACK_FIFO_DEFAULT; |
| 66 | module_param(kfifo_depth, uint, 0444); |
| 67 | |
| 68 | /* Number of minor devices this driver supports */ |
| 69 | #define NUM_MINORS 256 |
| 70 | |
| 71 | /* Maximum size of any one send data buffer we support */ |
| 72 | #define MAX_PACKET_SIZE (PAGE_SIZE * 2) |
| 73 | |
Alex Elder | 91262c3 | 2015-05-11 21:16:37 -0500 | [diff] [blame] | 74 | #define GB_LOOPBACK_MS_WAIT_MAX 1000 |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 75 | |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 76 | /* interface sysfs attributes */ |
Alex Elder | 19c2a44 | 2015-08-03 12:57:17 -0500 | [diff] [blame] | 77 | #define gb_loopback_ro_attr(field) \ |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 78 | static ssize_t field##_show(struct device *dev, \ |
| 79 | struct device_attribute *attr, \ |
| 80 | char *buf) \ |
| 81 | { \ |
| 82 | struct gb_connection *connection = to_gb_connection(dev); \ |
Alex Elder | 3f12c3e | 2015-08-03 12:57:11 -0500 | [diff] [blame] | 83 | struct gb_loopback *gb = connection->private; \ |
Alex Elder | 19c2a44 | 2015-08-03 12:57:17 -0500 | [diff] [blame] | 84 | return sprintf(buf, "%u\n", gb->field); \ |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 85 | } \ |
| 86 | static DEVICE_ATTR_RO(field) |
| 87 | |
| 88 | #define gb_loopback_ro_stats_attr(name, field, type) \ |
| 89 | static ssize_t name##_##field##_show(struct device *dev, \ |
| 90 | struct device_attribute *attr, \ |
| 91 | char *buf) \ |
| 92 | { \ |
| 93 | struct gb_connection *connection = to_gb_connection(dev); \ |
Alex Elder | 3f12c3e | 2015-08-03 12:57:11 -0500 | [diff] [blame] | 94 | struct gb_loopback *gb = connection->private; \ |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 95 | return sprintf(buf, "%"#type"\n", gb->name.field); \ |
| 96 | } \ |
| 97 | static DEVICE_ATTR_RO(name##_##field) |
| 98 | |
Alex Elder | 7a135a9 | 2015-08-03 12:57:18 -0500 | [diff] [blame] | 99 | #define gb_loopback_ro_avg_attr(name) \ |
| 100 | static ssize_t name##_avg_show(struct device *dev, \ |
| 101 | struct device_attribute *attr, \ |
| 102 | char *buf) \ |
| 103 | { \ |
| 104 | struct gb_connection *connection = to_gb_connection(dev); \ |
| 105 | struct gb_loopback *gb = connection->private; \ |
Alex Elder | ff71d39 | 2015-08-03 12:57:19 -0500 | [diff] [blame] | 106 | struct gb_loopback_stats *stats = &gb->name; \ |
| 107 | u32 count = stats->count ? stats->count : 1; \ |
| 108 | u64 avg = stats->sum + count / 2; /* round closest */ \ |
| 109 | u32 rem = do_div(avg, count); \ |
| 110 | return sprintf(buf, "%llu.%06u\n", avg, 1000000 * rem / count); \ |
Alex Elder | 7a135a9 | 2015-08-03 12:57:18 -0500 | [diff] [blame] | 111 | } \ |
| 112 | static DEVICE_ATTR_RO(name##_avg) |
| 113 | |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 114 | #define gb_loopback_stats_attrs(field) \ |
Alex Elder | e051c82 | 2015-08-03 12:57:14 -0500 | [diff] [blame] | 115 | gb_loopback_ro_stats_attr(field, min, u); \ |
| 116 | gb_loopback_ro_stats_attr(field, max, u); \ |
Alex Elder | 7a135a9 | 2015-08-03 12:57:18 -0500 | [diff] [blame] | 117 | gb_loopback_ro_avg_attr(field); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 118 | |
| 119 | #define gb_loopback_attr(field, type) \ |
| 120 | static ssize_t field##_show(struct device *dev, \ |
| 121 | struct device_attribute *attr, \ |
| 122 | char *buf) \ |
| 123 | { \ |
| 124 | struct gb_connection *connection = to_gb_connection(dev); \ |
Alex Elder | 3f12c3e | 2015-08-03 12:57:11 -0500 | [diff] [blame] | 125 | struct gb_loopback *gb = connection->private; \ |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 126 | return sprintf(buf, "%"#type"\n", gb->field); \ |
| 127 | } \ |
| 128 | static ssize_t field##_store(struct device *dev, \ |
| 129 | struct device_attribute *attr, \ |
| 130 | const char *buf, \ |
| 131 | size_t len) \ |
| 132 | { \ |
| 133 | int ret; \ |
| 134 | struct gb_connection *connection = to_gb_connection(dev); \ |
Alex Elder | 3f12c3e | 2015-08-03 12:57:11 -0500 | [diff] [blame] | 135 | struct gb_loopback *gb = connection->private; \ |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 136 | mutex_lock(&gb->mutex); \ |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 137 | ret = sscanf(buf, "%"#type, &gb->field); \ |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 138 | if (ret != 1) \ |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 139 | len = -EINVAL; \ |
| 140 | else \ |
Bryan O'Donoghue | cb60f49 | 2015-07-28 18:34:39 +0100 | [diff] [blame] | 141 | gb_loopback_check_attr(connection, gb); \ |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 142 | mutex_unlock(&gb->mutex); \ |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 143 | return len; \ |
| 144 | } \ |
| 145 | static DEVICE_ATTR_RW(field) |
| 146 | |
| 147 | static void gb_loopback_reset_stats(struct gb_loopback *gb); |
Bryan O'Donoghue | cb60f49 | 2015-07-28 18:34:39 +0100 | [diff] [blame] | 148 | static void gb_loopback_check_attr(struct gb_connection *connection, |
| 149 | struct gb_loopback *gb) |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 150 | { |
Alex Elder | 91262c3 | 2015-05-11 21:16:37 -0500 | [diff] [blame] | 151 | if (gb->ms_wait > GB_LOOPBACK_MS_WAIT_MAX) |
| 152 | gb->ms_wait = GB_LOOPBACK_MS_WAIT_MAX; |
Bryan O'Donoghue | c3bba87 | 2015-07-13 20:20:50 +0100 | [diff] [blame] | 153 | if (gb->size > gb->size_max) |
| 154 | gb->size = gb->size_max; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 155 | gb->error = 0; |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 156 | gb->iteration_count = 0; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 157 | gb_loopback_reset_stats(gb); |
Bryan O'Donoghue | 3dfe8aa | 2015-07-24 10:02:56 +0100 | [diff] [blame] | 158 | |
Bryan O'Donoghue | cb60f49 | 2015-07-28 18:34:39 +0100 | [diff] [blame] | 159 | if (kfifo_depth < gb->iteration_max) { |
| 160 | dev_warn(&connection->dev, |
| 161 | "iteration_max %u kfifo_depth %u cannot log all data\n", |
| 162 | gb->iteration_max, kfifo_depth); |
| 163 | } |
| 164 | |
Bryan O'Donoghue | 3dfe8aa | 2015-07-24 10:02:56 +0100 | [diff] [blame] | 165 | switch (gb->type) { |
| 166 | case GB_LOOPBACK_TYPE_PING: |
| 167 | case GB_LOOPBACK_TYPE_TRANSFER: |
| 168 | case GB_LOOPBACK_TYPE_SINK: |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 169 | kfifo_reset_out(&gb->kfifo); |
Bryan O'Donoghue | 3dfe8aa | 2015-07-24 10:02:56 +0100 | [diff] [blame] | 170 | wake_up(&gb->wq); |
| 171 | break; |
| 172 | default: |
| 173 | gb->type = 0; |
| 174 | break; |
| 175 | } |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 176 | } |
| 177 | |
| 178 | /* Time to send and receive one message */ |
| 179 | gb_loopback_stats_attrs(latency); |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 180 | /* Number of requests sent per second on this cport */ |
| 181 | gb_loopback_stats_attrs(requests_per_second); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 182 | /* Quantity of data sent and received on this cport */ |
| 183 | gb_loopback_stats_attrs(throughput); |
Bryan O'Donoghue | e140c75 | 2015-07-21 23:50:09 +0100 | [diff] [blame] | 184 | /* Number of errors encountered during loop */ |
Alex Elder | 19c2a44 | 2015-08-03 12:57:17 -0500 | [diff] [blame] | 185 | gb_loopback_ro_attr(error); |
Bryan O'Donoghue | e140c75 | 2015-07-21 23:50:09 +0100 | [diff] [blame] | 186 | /* The current index of the for (i = 0; i < iteration_max; i++) loop */ |
Alex Elder | 19c2a44 | 2015-08-03 12:57:17 -0500 | [diff] [blame] | 187 | gb_loopback_ro_attr(iteration_count); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 188 | |
| 189 | /* |
Bryan O'Donoghue | 799a3f0 | 2015-07-21 23:50:07 +0100 | [diff] [blame] | 190 | * Type of loopback message to send based on protocol type definitions |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 191 | * 0 => Don't send message |
Bryan O'Donoghue | 799a3f0 | 2015-07-21 23:50:07 +0100 | [diff] [blame] | 192 | * 2 => Send ping message continuously (message without payload) |
Alex Elder | 006335a | 2015-08-03 12:57:10 -0500 | [diff] [blame] | 193 | * 3 => Send transfer message continuously (message with payload, |
Bryan O'Donoghue | 799a3f0 | 2015-07-21 23:50:07 +0100 | [diff] [blame] | 194 | * payload returned in response) |
| 195 | * 4 => Send a sink message (message with payload, no payload in response) |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 196 | */ |
| 197 | gb_loopback_attr(type, d); |
| 198 | /* Size of transfer message payload: 0-4096 bytes */ |
| 199 | gb_loopback_attr(size, u); |
Alex Elder | 48f19ee | 2015-05-11 21:16:36 -0500 | [diff] [blame] | 200 | /* Time to wait between two messages: 0-1000 ms */ |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 201 | gb_loopback_attr(ms_wait, d); |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 202 | /* Maximum iterations for a given operation: 1-(2^32-1), 0 implies infinite */ |
| 203 | gb_loopback_attr(iteration_max, u); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 204 | |
| 205 | #define dev_stats_attrs(name) \ |
| 206 | &dev_attr_##name##_min.attr, \ |
| 207 | &dev_attr_##name##_max.attr, \ |
| 208 | &dev_attr_##name##_avg.attr |
| 209 | |
| 210 | static struct attribute *loopback_attrs[] = { |
| 211 | dev_stats_attrs(latency), |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 212 | dev_stats_attrs(requests_per_second), |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 213 | dev_stats_attrs(throughput), |
| 214 | &dev_attr_type.attr, |
| 215 | &dev_attr_size.attr, |
| 216 | &dev_attr_ms_wait.attr, |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 217 | &dev_attr_iteration_count.attr, |
| 218 | &dev_attr_iteration_max.attr, |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 219 | &dev_attr_error.attr, |
| 220 | NULL, |
| 221 | }; |
| 222 | ATTRIBUTE_GROUPS(loopback); |
| 223 | |
Bryan O'Donoghue | 4c19266 | 2015-08-11 13:50:53 +0100 | [diff] [blame] | 224 | static void gb_loopback_calc_latency(struct gb_loopback *gb, |
| 225 | struct timeval *ts, struct timeval *te) |
| 226 | { |
| 227 | u64 t1, t2; |
| 228 | |
| 229 | t1 = timeval_to_ns(ts); |
| 230 | t2 = timeval_to_ns(te); |
Bryan O'Donoghue | fd489e1 | 2015-08-11 13:50:54 +0100 | [diff] [blame^] | 231 | if (t2 > t1) |
| 232 | gb->elapsed_nsecs = t2 - t1; |
| 233 | else |
| 234 | gb->elapsed_nsecs = NSEC_PER_DAY - t2 + t1; |
Bryan O'Donoghue | 4c19266 | 2015-08-11 13:50:53 +0100 | [diff] [blame] | 235 | } |
| 236 | |
Bryan O'Donoghue | a7e6006 | 2015-07-28 18:34:35 +0100 | [diff] [blame] | 237 | static int gb_loopback_sink(struct gb_loopback *gb, u32 len) |
Bryan O'Donoghue | 384a7a3 | 2015-07-13 20:20:49 +0100 | [diff] [blame] | 238 | { |
| 239 | struct timeval ts, te; |
Bryan O'Donoghue | 384a7a3 | 2015-07-13 20:20:49 +0100 | [diff] [blame] | 240 | struct gb_loopback_transfer_request *request; |
| 241 | int retval; |
| 242 | |
| 243 | request = kmalloc(len + sizeof(*request), GFP_KERNEL); |
| 244 | if (!request) |
| 245 | return -ENOMEM; |
| 246 | |
| 247 | request->len = cpu_to_le32(len); |
| 248 | |
| 249 | do_gettimeofday(&ts); |
| 250 | retval = gb_operation_sync(gb->connection, GB_LOOPBACK_TYPE_SINK, |
| 251 | request, len + sizeof(*request), NULL, 0); |
Bryan O'Donoghue | c3bba87 | 2015-07-13 20:20:50 +0100 | [diff] [blame] | 252 | |
Bryan O'Donoghue | 384a7a3 | 2015-07-13 20:20:49 +0100 | [diff] [blame] | 253 | do_gettimeofday(&te); |
Bryan O'Donoghue | 4c19266 | 2015-08-11 13:50:53 +0100 | [diff] [blame] | 254 | gb_loopback_calc_latency(gb, &ts, &te); |
Bryan O'Donoghue | 384a7a3 | 2015-07-13 20:20:49 +0100 | [diff] [blame] | 255 | |
| 256 | kfree(request); |
| 257 | return retval; |
| 258 | } |
| 259 | |
Bryan O'Donoghue | a7e6006 | 2015-07-28 18:34:35 +0100 | [diff] [blame] | 260 | static int gb_loopback_transfer(struct gb_loopback *gb, u32 len) |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 261 | { |
| 262 | struct timeval ts, te; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 263 | struct gb_loopback_transfer_request *request; |
| 264 | struct gb_loopback_transfer_response *response; |
| 265 | int retval; |
| 266 | |
| 267 | request = kmalloc(len + sizeof(*request), GFP_KERNEL); |
| 268 | if (!request) |
| 269 | return -ENOMEM; |
| 270 | response = kmalloc(len + sizeof(*response), GFP_KERNEL); |
| 271 | if (!response) { |
| 272 | kfree(request); |
| 273 | return -ENOMEM; |
| 274 | } |
| 275 | |
| 276 | request->len = cpu_to_le32(len); |
| 277 | |
| 278 | do_gettimeofday(&ts); |
| 279 | retval = gb_operation_sync(gb->connection, GB_LOOPBACK_TYPE_TRANSFER, |
| 280 | request, len + sizeof(*request), |
| 281 | response, len + sizeof(*response)); |
| 282 | do_gettimeofday(&te); |
Bryan O'Donoghue | 4c19266 | 2015-08-11 13:50:53 +0100 | [diff] [blame] | 283 | gb_loopback_calc_latency(gb, &ts, &te); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 284 | |
| 285 | if (retval) |
| 286 | goto gb_error; |
| 287 | |
| 288 | if (memcmp(request->data, response->data, len)) |
| 289 | retval = -EREMOTEIO; |
| 290 | |
| 291 | gb_error: |
| 292 | kfree(request); |
| 293 | kfree(response); |
| 294 | |
| 295 | return retval; |
| 296 | } |
| 297 | |
Bryan O'Donoghue | a7e6006 | 2015-07-28 18:34:35 +0100 | [diff] [blame] | 298 | static int gb_loopback_ping(struct gb_loopback *gb) |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 299 | { |
| 300 | struct timeval ts, te; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 301 | int retval; |
| 302 | |
| 303 | do_gettimeofday(&ts); |
| 304 | retval = gb_operation_sync(gb->connection, GB_LOOPBACK_TYPE_PING, |
| 305 | NULL, 0, NULL, 0); |
| 306 | do_gettimeofday(&te); |
Bryan O'Donoghue | 4c19266 | 2015-08-11 13:50:53 +0100 | [diff] [blame] | 307 | gb_loopback_calc_latency(gb, &ts, &te); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 308 | |
| 309 | return retval; |
| 310 | } |
| 311 | |
Alex Elder | ac1c284 | 2015-05-11 21:16:39 -0500 | [diff] [blame] | 312 | static int gb_loopback_request_recv(u8 type, struct gb_operation *operation) |
| 313 | { |
| 314 | struct gb_connection *connection = operation->connection; |
Bryan O'Donoghue | c3bba87 | 2015-07-13 20:20:50 +0100 | [diff] [blame] | 315 | struct gb_loopback *gb = connection->private; |
Alex Elder | ac1c284 | 2015-05-11 21:16:39 -0500 | [diff] [blame] | 316 | struct gb_loopback_transfer_request *request; |
| 317 | struct gb_loopback_transfer_response *response; |
Bryan O'Donoghue | e51eafe | 2015-07-14 00:53:13 +0100 | [diff] [blame] | 318 | size_t len; |
Alex Elder | ac1c284 | 2015-05-11 21:16:39 -0500 | [diff] [blame] | 319 | |
| 320 | /* By convention, the AP initiates the version operation */ |
| 321 | switch (type) { |
| 322 | case GB_LOOPBACK_TYPE_PROTOCOL_VERSION: |
| 323 | dev_err(&connection->dev, |
| 324 | "module-initiated version operation\n"); |
| 325 | return -EINVAL; |
| 326 | case GB_LOOPBACK_TYPE_PING: |
Bryan O'Donoghue | 384a7a3 | 2015-07-13 20:20:49 +0100 | [diff] [blame] | 327 | case GB_LOOPBACK_TYPE_SINK: |
Alex Elder | ac1c284 | 2015-05-11 21:16:39 -0500 | [diff] [blame] | 328 | return 0; |
| 329 | case GB_LOOPBACK_TYPE_TRANSFER: |
| 330 | if (operation->request->payload_size < sizeof(*request)) { |
| 331 | dev_err(&connection->dev, |
| 332 | "transfer request too small (%zu < %zu)\n", |
| 333 | operation->request->payload_size, |
| 334 | sizeof(*request)); |
| 335 | return -EINVAL; /* -EMSGSIZE */ |
| 336 | } |
| 337 | request = operation->request->payload; |
| 338 | len = le32_to_cpu(request->len); |
Bryan O'Donoghue | c3bba87 | 2015-07-13 20:20:50 +0100 | [diff] [blame] | 339 | if (len > gb->size_max) { |
| 340 | dev_err(&connection->dev, |
| 341 | "transfer request too large (%zu > %zu)\n", |
| 342 | len, gb->size_max); |
| 343 | return -EINVAL; |
| 344 | } |
| 345 | |
Alex Elder | ac1c284 | 2015-05-11 21:16:39 -0500 | [diff] [blame] | 346 | if (len) { |
Johan Hovold | 1c7658c | 2015-07-17 18:50:25 +0200 | [diff] [blame] | 347 | if (!gb_operation_response_alloc(operation, len, |
| 348 | GFP_KERNEL)) { |
Alex Elder | ac1c284 | 2015-05-11 21:16:39 -0500 | [diff] [blame] | 349 | dev_err(&connection->dev, |
| 350 | "error allocating response\n"); |
| 351 | return -ENOMEM; |
| 352 | } |
| 353 | response = operation->response->payload; |
| 354 | memcpy(response->data, request->data, len); |
| 355 | } |
| 356 | return 0; |
| 357 | default: |
| 358 | dev_err(&connection->dev, |
| 359 | "unsupported request: %hhu\n", type); |
| 360 | return -EINVAL; |
| 361 | } |
| 362 | } |
| 363 | |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 364 | static void gb_loopback_reset_stats(struct gb_loopback *gb) |
| 365 | { |
| 366 | struct gb_loopback_stats reset = { |
Alex Elder | e051c82 | 2015-08-03 12:57:14 -0500 | [diff] [blame] | 367 | .min = U32_MAX, |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 368 | }; |
| 369 | memcpy(&gb->latency, &reset, sizeof(struct gb_loopback_stats)); |
| 370 | memcpy(&gb->throughput, &reset, sizeof(struct gb_loopback_stats)); |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 371 | memcpy(&gb->requests_per_second, &reset, |
| 372 | sizeof(struct gb_loopback_stats)); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 373 | } |
| 374 | |
Alex Elder | a6e7e53 | 2015-08-03 12:57:13 -0500 | [diff] [blame] | 375 | static void gb_loopback_update_stats(struct gb_loopback_stats *stats, u32 val) |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 376 | { |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 377 | if (stats->min > val) |
| 378 | stats->min = val; |
| 379 | if (stats->max < val) |
| 380 | stats->max = val; |
| 381 | stats->sum += val; |
| 382 | stats->count++; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 383 | } |
| 384 | |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 385 | static void gb_loopback_requests_update(struct gb_loopback *gb, u32 latency) |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 386 | { |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 387 | u32 req = USEC_PER_SEC; |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 388 | |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 389 | do_div(req, latency); |
| 390 | gb_loopback_update_stats(&gb->requests_per_second, req); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 391 | } |
| 392 | |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 393 | static void gb_loopback_throughput_update(struct gb_loopback *gb, u32 latency) |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 394 | { |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 395 | u32 throughput; |
Bryan O'Donoghue | f7908e4 | 2015-07-13 20:20:51 +0100 | [diff] [blame] | 396 | u32 aggregate_size = sizeof(struct gb_operation_msg_hdr) * 2; |
| 397 | |
| 398 | switch (gb->type) { |
| 399 | case GB_LOOPBACK_TYPE_PING: |
| 400 | break; |
| 401 | case GB_LOOPBACK_TYPE_SINK: |
| 402 | aggregate_size += sizeof(struct gb_loopback_transfer_request) + |
| 403 | gb->size; |
| 404 | break; |
| 405 | case GB_LOOPBACK_TYPE_TRANSFER: |
| 406 | aggregate_size += sizeof(struct gb_loopback_transfer_request) + |
| 407 | sizeof(struct gb_loopback_transfer_response) + |
| 408 | gb->size * 2; |
| 409 | break; |
| 410 | default: |
| 411 | return; |
| 412 | } |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 413 | |
| 414 | /* Calculate bytes per second */ |
| 415 | throughput = USEC_PER_SEC; |
| 416 | do_div(throughput, latency); |
| 417 | throughput *= aggregate_size; |
| 418 | gb_loopback_update_stats(&gb->throughput, throughput); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 419 | } |
| 420 | |
Bryan O'Donoghue | a7e6006 | 2015-07-28 18:34:35 +0100 | [diff] [blame] | 421 | static void gb_loopback_calculate_stats(struct gb_loopback *gb) |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 422 | { |
| 423 | u32 lat; |
Johan Hovold | 1ffc12b | 2015-04-16 09:53:59 +0200 | [diff] [blame] | 424 | u64 tmp; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 425 | |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 426 | /* Express latency in terms of microseconds */ |
| 427 | tmp = gb->elapsed_nsecs; |
| 428 | do_div(tmp, NSEC_PER_USEC); |
Johan Hovold | 1ffc12b | 2015-04-16 09:53:59 +0200 | [diff] [blame] | 429 | lat = tmp; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 430 | |
Alex Elder | 006335a | 2015-08-03 12:57:10 -0500 | [diff] [blame] | 431 | /* Log latency statistic */ |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 432 | gb_loopback_update_stats(&gb->latency, lat); |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 433 | kfifo_in(&gb->kfifo, (unsigned char *)&lat, sizeof(lat)); |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 434 | |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 435 | /* Log throughput and requests using latency as benchmark */ |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 436 | gb_loopback_throughput_update(gb, lat); |
Bryan O'Donoghue | 583cbf5 | 2015-07-21 23:50:10 +0100 | [diff] [blame] | 437 | gb_loopback_requests_update(gb, lat); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 438 | } |
| 439 | |
| 440 | static int gb_loopback_fn(void *data) |
| 441 | { |
| 442 | int error = 0; |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 443 | int ms_wait; |
Alex Elder | 3f12c3e | 2015-08-03 12:57:11 -0500 | [diff] [blame] | 444 | struct gb_loopback *gb = data; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 445 | |
Bryan O'Donoghue | 3dfe8aa | 2015-07-24 10:02:56 +0100 | [diff] [blame] | 446 | while (1) { |
| 447 | if (!gb->type) |
| 448 | wait_event_interruptible(gb->wq, gb->type || |
| 449 | kthread_should_stop()); |
| 450 | if (kthread_should_stop()) |
| 451 | break; |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 452 | |
| 453 | mutex_lock(&gb->mutex); |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 454 | if (gb->iteration_max) { |
| 455 | if (gb->iteration_count < gb->iteration_max) { |
| 456 | gb->iteration_count++; |
Greg Kroah-Hartman | c2939f4 | 2015-07-22 11:09:23 -0700 | [diff] [blame] | 457 | sysfs_notify(&gb->connection->dev.kobj, NULL, |
| 458 | "iteration_count"); |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 459 | } else { |
| 460 | gb->type = 0; |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 461 | mutex_unlock(&gb->mutex); |
Bryan O'Donoghue | 00af658 | 2015-07-21 23:50:08 +0100 | [diff] [blame] | 462 | continue; |
| 463 | } |
| 464 | } |
Bryan O'Donoghue | a598f43 | 2015-07-13 20:20:48 +0100 | [diff] [blame] | 465 | if (gb->type == GB_LOOPBACK_TYPE_PING) |
Bryan O'Donoghue | a7e6006 | 2015-07-28 18:34:35 +0100 | [diff] [blame] | 466 | error = gb_loopback_ping(gb); |
Bryan O'Donoghue | a598f43 | 2015-07-13 20:20:48 +0100 | [diff] [blame] | 467 | else if (gb->type == GB_LOOPBACK_TYPE_TRANSFER) |
Bryan O'Donoghue | a7e6006 | 2015-07-28 18:34:35 +0100 | [diff] [blame] | 468 | error = gb_loopback_transfer(gb, gb->size); |
Bryan O'Donoghue | 384a7a3 | 2015-07-13 20:20:49 +0100 | [diff] [blame] | 469 | else if (gb->type == GB_LOOPBACK_TYPE_SINK) |
Bryan O'Donoghue | a7e6006 | 2015-07-28 18:34:35 +0100 | [diff] [blame] | 470 | error = gb_loopback_sink(gb, gb->size); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 471 | if (error) |
| 472 | gb->error++; |
Bryan O'Donoghue | a7e6006 | 2015-07-28 18:34:35 +0100 | [diff] [blame] | 473 | gb_loopback_calculate_stats(gb); |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 474 | ms_wait = gb->ms_wait; |
| 475 | mutex_unlock(&gb->mutex); |
| 476 | if (ms_wait) |
| 477 | msleep(ms_wait); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 478 | } |
| 479 | return 0; |
| 480 | } |
| 481 | |
| 482 | static int gb_loopback_connection_init(struct gb_connection *connection) |
| 483 | { |
| 484 | struct gb_loopback *gb; |
| 485 | int retval; |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 486 | int minor; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 487 | |
| 488 | gb = kzalloc(sizeof(*gb), GFP_KERNEL); |
| 489 | if (!gb) |
| 490 | return -ENOMEM; |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 491 | gb_loopback_reset_stats(gb); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 492 | |
| 493 | gb->connection = connection; |
| 494 | connection->private = gb; |
Greg Kroah-Hartman | 7a51b93 | 2015-03-31 23:02:34 +0200 | [diff] [blame] | 495 | retval = sysfs_create_groups(&connection->dev.kobj, loopback_groups); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 496 | if (retval) |
Phong Tran | 6f8528e | 2015-05-14 23:03:04 +0700 | [diff] [blame] | 497 | goto out_free; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 498 | |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 499 | /* Get a minor number */ |
| 500 | minor = ida_simple_get(&minors, 0, 0, GFP_KERNEL); |
| 501 | if (minor < 0) { |
| 502 | retval = minor; |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 503 | goto out_sysfs; |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 504 | } |
| 505 | |
Bryan O'Donoghue | c3bba87 | 2015-07-13 20:20:50 +0100 | [diff] [blame] | 506 | /* Calculate maximum payload */ |
| 507 | gb->size_max = gb_operation_get_payload_size_max(connection); |
| 508 | if (gb->size_max <= sizeof(struct gb_loopback_transfer_request)) { |
| 509 | retval = -EINVAL; |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 510 | goto out_minor; |
Bryan O'Donoghue | c3bba87 | 2015-07-13 20:20:50 +0100 | [diff] [blame] | 511 | } |
| 512 | gb->size_max -= sizeof(struct gb_loopback_transfer_request); |
| 513 | |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 514 | /* Allocate kfifo */ |
| 515 | if (kfifo_alloc(&gb->kfifo, kfifo_depth * sizeof(u32), |
| 516 | GFP_KERNEL)) { |
| 517 | retval = -ENOMEM; |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 518 | goto out_minor; |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 519 | } |
| 520 | |
| 521 | /* Create device entry */ |
| 522 | gb->dev = MKDEV(loopback_major, minor); |
| 523 | cdev_init(&gb->cdev, &loopback_fops); |
| 524 | retval = cdev_add(&gb->cdev, gb->dev, 1); |
| 525 | if (retval) |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 526 | goto out_kfifo; |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 527 | |
| 528 | gb->device = device_create(loopback_class, &connection->dev, gb->dev, |
| 529 | gb, "gb!loopback%d", minor); |
| 530 | if (IS_ERR(gb->device)) { |
| 531 | retval = PTR_ERR(gb->device); |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 532 | goto out_cdev; |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 533 | } |
| 534 | |
| 535 | /* Fork worker thread */ |
Bryan O'Donoghue | 3dfe8aa | 2015-07-24 10:02:56 +0100 | [diff] [blame] | 536 | init_waitqueue_head(&gb->wq); |
Bryan O'Donoghue | 85d678c | 2015-07-28 18:34:36 +0100 | [diff] [blame] | 537 | mutex_init(&gb->mutex); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 538 | gb->task = kthread_run(gb_loopback_fn, gb, "gb_loopback"); |
| 539 | if (IS_ERR(gb->task)) { |
Alex Elder | 69f6034 | 2015-05-11 21:16:35 -0500 | [diff] [blame] | 540 | retval = PTR_ERR(gb->task); |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 541 | goto out_device; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 542 | } |
| 543 | |
| 544 | return 0; |
| 545 | |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 546 | out_device: |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 547 | device_del(gb->device); |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 548 | out_cdev: |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 549 | cdev_del(&gb->cdev); |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 550 | out_kfifo: |
| 551 | kfifo_free(&gb->kfifo); |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 552 | out_minor: |
| 553 | ida_simple_remove(&minors, minor); |
| 554 | out_sysfs: |
Phong Tran | 6f8528e | 2015-05-14 23:03:04 +0700 | [diff] [blame] | 555 | sysfs_remove_groups(&connection->dev.kobj, loopback_groups); |
| 556 | out_free: |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 557 | connection->private = NULL; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 558 | kfree(gb); |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 559 | |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 560 | return retval; |
| 561 | } |
| 562 | |
| 563 | static void gb_loopback_connection_exit(struct gb_connection *connection) |
| 564 | { |
| 565 | struct gb_loopback *gb = connection->private; |
| 566 | |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 567 | connection->private = NULL; |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 568 | if (!IS_ERR_OR_NULL(gb->task)) |
| 569 | kthread_stop(gb->task); |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 570 | |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 571 | device_del(gb->device); |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 572 | cdev_del(&gb->cdev); |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 573 | kfifo_free(&gb->kfifo); |
Alex Elder | 1fb807c | 2015-08-03 12:57:20 -0500 | [diff] [blame] | 574 | ida_simple_remove(&minors, MINOR(gb->dev)); |
Greg Kroah-Hartman | 7a51b93 | 2015-03-31 23:02:34 +0200 | [diff] [blame] | 575 | sysfs_remove_groups(&connection->dev.kobj, loopback_groups); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 576 | kfree(gb); |
| 577 | } |
| 578 | |
| 579 | static struct gb_protocol loopback_protocol = { |
| 580 | .name = "loopback", |
| 581 | .id = GREYBUS_PROTOCOL_LOOPBACK, |
| 582 | .major = GB_LOOPBACK_VERSION_MAJOR, |
| 583 | .minor = GB_LOOPBACK_VERSION_MINOR, |
| 584 | .connection_init = gb_loopback_connection_init, |
| 585 | .connection_exit = gb_loopback_connection_exit, |
Alex Elder | ac1c284 | 2015-05-11 21:16:39 -0500 | [diff] [blame] | 586 | .request_recv = gb_loopback_request_recv, |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 587 | }; |
| 588 | |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 589 | static int loopback_open(struct inode *inode, struct file *file) |
| 590 | { |
| 591 | struct cdev *cdev = inode->i_cdev; |
| 592 | struct gb_loopback *gb = container_of(cdev, struct gb_loopback, cdev); |
| 593 | |
| 594 | file->private_data = gb; |
| 595 | return 0; |
| 596 | } |
| 597 | |
| 598 | static ssize_t loopback_read(struct file *file, char __user *buf, size_t count, |
| 599 | loff_t *ppos) |
| 600 | { |
| 601 | struct gb_loopback *gb = file->private_data; |
| 602 | size_t fifo_len; |
| 603 | int retval; |
| 604 | |
Alex Elder | 006335a | 2015-08-03 12:57:10 -0500 | [diff] [blame] | 605 | if (!count || count % sizeof(u32)) |
Bryan O'Donoghue | cbd204b | 2015-07-28 18:34:38 +0100 | [diff] [blame] | 606 | return -EINVAL; |
| 607 | |
| 608 | mutex_lock(&gb->mutex); |
| 609 | fifo_len = kfifo_len(&gb->kfifo); |
| 610 | if (kfifo_to_user(&gb->kfifo, buf, min(fifo_len, count), &retval) != 0) |
| 611 | retval = -EIO; |
| 612 | mutex_unlock(&gb->mutex); |
| 613 | |
| 614 | return retval; |
| 615 | } |
| 616 | |
| 617 | static const struct file_operations loopback_fops = { |
| 618 | .owner = THIS_MODULE, |
| 619 | .read = loopback_read, |
| 620 | .open = loopback_open, |
| 621 | .llseek = noop_llseek, |
| 622 | }; |
| 623 | |
| 624 | static int loopback_init(void) |
| 625 | { |
| 626 | dev_t dev; |
| 627 | int retval; |
| 628 | |
| 629 | loopback_class = class_create(THIS_MODULE, "gb_loopback"); |
| 630 | if (IS_ERR(loopback_class)) { |
| 631 | retval = PTR_ERR(loopback_class); |
| 632 | goto error_class; |
| 633 | } |
| 634 | |
| 635 | retval = alloc_chrdev_region(&dev, 0, NUM_MINORS, "gb_loopback"); |
| 636 | if (retval < 0) |
| 637 | goto error_chrdev; |
| 638 | |
| 639 | loopback_major = MAJOR(dev); |
| 640 | |
| 641 | retval = gb_protocol_register(&loopback_protocol); |
| 642 | if (retval) |
| 643 | goto error_gb; |
| 644 | |
| 645 | return 0; |
| 646 | |
| 647 | error_gb: |
| 648 | unregister_chrdev_region(dev, NUM_MINORS); |
| 649 | error_chrdev: |
| 650 | class_destroy(loopback_class); |
| 651 | error_class: |
| 652 | return retval; |
| 653 | } |
| 654 | module_init(loopback_init); |
| 655 | |
| 656 | static void __exit loopback_exit(void) |
| 657 | { |
| 658 | gb_protocol_deregister(&loopback_protocol); |
| 659 | unregister_chrdev_region(MKDEV(loopback_major, 0), NUM_MINORS); |
| 660 | class_destroy(loopback_class); |
| 661 | ida_destroy(&minors); |
| 662 | } |
| 663 | module_exit(loopback_exit); |
Alexandre Bailon | 355a705 | 2015-03-31 09:51:59 +0200 | [diff] [blame] | 664 | |
| 665 | MODULE_LICENSE("GPL v2"); |