Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 1 | /****************************************************************************** |
| 2 | * evtchn.c |
| 3 | * |
| 4 | * Driver for receiving and demuxing event-channel signals. |
| 5 | * |
| 6 | * Copyright (c) 2004-2005, K A Fraser |
| 7 | * Multi-process extensions Copyright (c) 2004, Steven Smith |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or |
| 10 | * modify it under the terms of the GNU General Public License version 2 |
| 11 | * as published by the Free Software Foundation; or, when distributed |
| 12 | * separately from the Linux kernel or incorporated into other |
| 13 | * software packages, subject to the following license: |
| 14 | * |
| 15 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 16 | * of this source file (the "Software"), to deal in the Software without |
| 17 | * restriction, including without limitation the rights to use, copy, modify, |
| 18 | * merge, publish, distribute, sublicense, and/or sell copies of the Software, |
| 19 | * and to permit persons to whom the Software is furnished to do so, subject to |
| 20 | * the following conditions: |
| 21 | * |
| 22 | * The above copyright notice and this permission notice shall be included in |
| 23 | * all copies or substantial portions of the Software. |
| 24 | * |
| 25 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 26 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 27 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 28 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 29 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| 30 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| 31 | * IN THE SOFTWARE. |
| 32 | */ |
| 33 | |
Joe Perches | 283c097 | 2013-06-28 03:21:41 -0700 | [diff] [blame] | 34 | #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt |
| 35 | |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 36 | #include <linux/module.h> |
| 37 | #include <linux/kernel.h> |
| 38 | #include <linux/sched.h> |
| 39 | #include <linux/slab.h> |
| 40 | #include <linux/string.h> |
| 41 | #include <linux/errno.h> |
| 42 | #include <linux/fs.h> |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 43 | #include <linux/miscdevice.h> |
| 44 | #include <linux/major.h> |
| 45 | #include <linux/proc_fs.h> |
| 46 | #include <linux/stat.h> |
| 47 | #include <linux/poll.h> |
| 48 | #include <linux/irq.h> |
| 49 | #include <linux/init.h> |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 50 | #include <linux/mutex.h> |
| 51 | #include <linux/cpu.h> |
Jeremy Fitzhardinge | 1ccbf53 | 2009-10-06 15:11:14 -0700 | [diff] [blame] | 52 | |
| 53 | #include <xen/xen.h> |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 54 | #include <xen/events.h> |
| 55 | #include <xen/evtchn.h> |
| 56 | #include <asm/xen/hypervisor.h> |
| 57 | |
| 58 | struct per_user_data { |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 59 | struct mutex bind_mutex; /* serialize bind/unbind operations */ |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 60 | struct rb_root evtchns; |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 61 | |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 62 | /* Notification ring, accessed via /dev/xen/evtchn. */ |
| 63 | #define EVTCHN_RING_SIZE (PAGE_SIZE / sizeof(evtchn_port_t)) |
| 64 | #define EVTCHN_RING_MASK(_i) ((_i)&(EVTCHN_RING_SIZE-1)) |
| 65 | evtchn_port_t *ring; |
| 66 | unsigned int ring_cons, ring_prod, ring_overflow; |
| 67 | struct mutex ring_cons_mutex; /* protect against concurrent readers */ |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 68 | spinlock_t ring_prod_lock; /* product against concurrent interrupts */ |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 69 | |
| 70 | /* Processes wait on this queue when ring is empty. */ |
| 71 | wait_queue_head_t evtchn_wait; |
| 72 | struct fasync_struct *evtchn_async_queue; |
| 73 | const char *name; |
| 74 | }; |
| 75 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 76 | struct user_evtchn { |
| 77 | struct rb_node node; |
| 78 | struct per_user_data *user; |
| 79 | unsigned port; |
| 80 | bool enabled; |
| 81 | }; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 82 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 83 | static int add_evtchn(struct per_user_data *u, struct user_evtchn *evtchn) |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 84 | { |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 85 | struct rb_node **new = &(u->evtchns.rb_node), *parent = NULL; |
| 86 | |
| 87 | while (*new) { |
| 88 | struct user_evtchn *this; |
| 89 | |
| 90 | this = container_of(*new, struct user_evtchn, node); |
| 91 | |
| 92 | parent = *new; |
| 93 | if (this->port < evtchn->port) |
| 94 | new = &((*new)->rb_left); |
| 95 | else if (this->port > evtchn->port) |
| 96 | new = &((*new)->rb_right); |
| 97 | else |
| 98 | return -EEXIST; |
| 99 | } |
| 100 | |
| 101 | /* Add new node and rebalance tree. */ |
| 102 | rb_link_node(&evtchn->node, parent, new); |
| 103 | rb_insert_color(&evtchn->node, &u->evtchns); |
| 104 | |
| 105 | return 0; |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 106 | } |
| 107 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 108 | static void del_evtchn(struct per_user_data *u, struct user_evtchn *evtchn) |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 109 | { |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 110 | rb_erase(&evtchn->node, &u->evtchns); |
| 111 | kfree(evtchn); |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 112 | } |
| 113 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 114 | static struct user_evtchn *find_evtchn(struct per_user_data *u, unsigned port) |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 115 | { |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 116 | struct rb_node *node = u->evtchns.rb_node; |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 117 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 118 | while (node) { |
| 119 | struct user_evtchn *evtchn; |
| 120 | |
| 121 | evtchn = container_of(node, struct user_evtchn, node); |
| 122 | |
| 123 | if (evtchn->port < port) |
| 124 | node = node->rb_left; |
| 125 | else if (evtchn->port > port) |
| 126 | node = node->rb_right; |
| 127 | else |
| 128 | return evtchn; |
| 129 | } |
| 130 | return NULL; |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 131 | } |
| 132 | |
Jeremy Fitzhardinge | 70697d54 | 2010-10-05 11:13:44 -0700 | [diff] [blame] | 133 | static irqreturn_t evtchn_interrupt(int irq, void *data) |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 134 | { |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 135 | struct user_evtchn *evtchn = data; |
| 136 | struct per_user_data *u = evtchn->user; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 137 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 138 | WARN(!evtchn->enabled, |
Jeremy Fitzhardinge | 0edce91 | 2009-09-18 16:55:29 -0700 | [diff] [blame] | 139 | "Interrupt for port %d, but apparently not enabled; per-user %p\n", |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 140 | evtchn->port, u); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 141 | |
| 142 | disable_irq_nosync(irq); |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 143 | evtchn->enabled = false; |
| 144 | |
| 145 | spin_lock(&u->ring_prod_lock); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 146 | |
| 147 | if ((u->ring_prod - u->ring_cons) < EVTCHN_RING_SIZE) { |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 148 | u->ring[EVTCHN_RING_MASK(u->ring_prod)] = evtchn->port; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 149 | wmb(); /* Ensure ring contents visible */ |
| 150 | if (u->ring_cons == u->ring_prod++) { |
| 151 | wake_up_interruptible(&u->evtchn_wait); |
| 152 | kill_fasync(&u->evtchn_async_queue, |
| 153 | SIGIO, POLL_IN); |
| 154 | } |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 155 | } else |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 156 | u->ring_overflow = 1; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 157 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 158 | spin_unlock(&u->ring_prod_lock); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 159 | |
| 160 | return IRQ_HANDLED; |
| 161 | } |
| 162 | |
| 163 | static ssize_t evtchn_read(struct file *file, char __user *buf, |
| 164 | size_t count, loff_t *ppos) |
| 165 | { |
| 166 | int rc; |
| 167 | unsigned int c, p, bytes1 = 0, bytes2 = 0; |
| 168 | struct per_user_data *u = file->private_data; |
| 169 | |
| 170 | /* Whole number of ports. */ |
| 171 | count &= ~(sizeof(evtchn_port_t)-1); |
| 172 | |
| 173 | if (count == 0) |
| 174 | return 0; |
| 175 | |
| 176 | if (count > PAGE_SIZE) |
| 177 | count = PAGE_SIZE; |
| 178 | |
| 179 | for (;;) { |
| 180 | mutex_lock(&u->ring_cons_mutex); |
| 181 | |
| 182 | rc = -EFBIG; |
| 183 | if (u->ring_overflow) |
| 184 | goto unlock_out; |
| 185 | |
| 186 | c = u->ring_cons; |
| 187 | p = u->ring_prod; |
| 188 | if (c != p) |
| 189 | break; |
| 190 | |
| 191 | mutex_unlock(&u->ring_cons_mutex); |
| 192 | |
| 193 | if (file->f_flags & O_NONBLOCK) |
| 194 | return -EAGAIN; |
| 195 | |
| 196 | rc = wait_event_interruptible(u->evtchn_wait, |
| 197 | u->ring_cons != u->ring_prod); |
| 198 | if (rc) |
| 199 | return rc; |
| 200 | } |
| 201 | |
| 202 | /* Byte lengths of two chunks. Chunk split (if any) is at ring wrap. */ |
| 203 | if (((c ^ p) & EVTCHN_RING_SIZE) != 0) { |
| 204 | bytes1 = (EVTCHN_RING_SIZE - EVTCHN_RING_MASK(c)) * |
| 205 | sizeof(evtchn_port_t); |
| 206 | bytes2 = EVTCHN_RING_MASK(p) * sizeof(evtchn_port_t); |
| 207 | } else { |
| 208 | bytes1 = (p - c) * sizeof(evtchn_port_t); |
| 209 | bytes2 = 0; |
| 210 | } |
| 211 | |
| 212 | /* Truncate chunks according to caller's maximum byte count. */ |
| 213 | if (bytes1 > count) { |
| 214 | bytes1 = count; |
| 215 | bytes2 = 0; |
| 216 | } else if ((bytes1 + bytes2) > count) { |
| 217 | bytes2 = count - bytes1; |
| 218 | } |
| 219 | |
| 220 | rc = -EFAULT; |
| 221 | rmb(); /* Ensure that we see the port before we copy it. */ |
| 222 | if (copy_to_user(buf, &u->ring[EVTCHN_RING_MASK(c)], bytes1) || |
| 223 | ((bytes2 != 0) && |
| 224 | copy_to_user(&buf[bytes1], &u->ring[0], bytes2))) |
| 225 | goto unlock_out; |
| 226 | |
| 227 | u->ring_cons += (bytes1 + bytes2) / sizeof(evtchn_port_t); |
| 228 | rc = bytes1 + bytes2; |
| 229 | |
| 230 | unlock_out: |
| 231 | mutex_unlock(&u->ring_cons_mutex); |
| 232 | return rc; |
| 233 | } |
| 234 | |
| 235 | static ssize_t evtchn_write(struct file *file, const char __user *buf, |
| 236 | size_t count, loff_t *ppos) |
| 237 | { |
| 238 | int rc, i; |
| 239 | evtchn_port_t *kbuf = (evtchn_port_t *)__get_free_page(GFP_KERNEL); |
| 240 | struct per_user_data *u = file->private_data; |
| 241 | |
| 242 | if (kbuf == NULL) |
| 243 | return -ENOMEM; |
| 244 | |
| 245 | /* Whole number of ports. */ |
| 246 | count &= ~(sizeof(evtchn_port_t)-1); |
| 247 | |
| 248 | rc = 0; |
| 249 | if (count == 0) |
| 250 | goto out; |
| 251 | |
| 252 | if (count > PAGE_SIZE) |
| 253 | count = PAGE_SIZE; |
| 254 | |
| 255 | rc = -EFAULT; |
| 256 | if (copy_from_user(kbuf, buf, count) != 0) |
| 257 | goto out; |
| 258 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 259 | mutex_lock(&u->bind_mutex); |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 260 | |
| 261 | for (i = 0; i < (count/sizeof(evtchn_port_t)); i++) { |
| 262 | unsigned port = kbuf[i]; |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 263 | struct user_evtchn *evtchn; |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 264 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 265 | evtchn = find_evtchn(u, port); |
| 266 | if (evtchn && !evtchn->enabled) { |
| 267 | evtchn->enabled = true; |
Jeremy Fitzhardinge | e3cc067 | 2009-09-18 16:31:22 -0700 | [diff] [blame] | 268 | enable_irq(irq_from_evtchn(port)); |
| 269 | } |
| 270 | } |
| 271 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 272 | mutex_unlock(&u->bind_mutex); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 273 | |
| 274 | rc = count; |
| 275 | |
| 276 | out: |
| 277 | free_page((unsigned long)kbuf); |
| 278 | return rc; |
| 279 | } |
| 280 | |
| 281 | static int evtchn_bind_to_user(struct per_user_data *u, int port) |
| 282 | { |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 283 | struct user_evtchn *evtchn; |
| 284 | struct evtchn_close close; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 285 | int rc = 0; |
| 286 | |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 287 | /* |
| 288 | * Ports are never reused, so every caller should pass in a |
| 289 | * unique port. |
| 290 | * |
| 291 | * (Locking not necessary because we haven't registered the |
| 292 | * interrupt handler yet, and our caller has already |
| 293 | * serialized bind operations.) |
| 294 | */ |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 295 | |
| 296 | evtchn = kzalloc(sizeof(*evtchn), GFP_KERNEL); |
| 297 | if (!evtchn) |
| 298 | return -ENOMEM; |
| 299 | |
| 300 | evtchn->user = u; |
| 301 | evtchn->port = port; |
| 302 | evtchn->enabled = true; /* start enabled */ |
| 303 | |
| 304 | rc = add_evtchn(u, evtchn); |
| 305 | if (rc < 0) |
| 306 | goto err; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 307 | |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 308 | rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, IRQF_DISABLED, |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 309 | u->name, evtchn); |
| 310 | if (rc < 0) |
| 311 | goto err; |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 312 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 313 | rc = evtchn_make_refcounted(port); |
| 314 | return rc; |
| 315 | |
| 316 | err: |
| 317 | /* bind failed, should close the port now */ |
| 318 | close.port = port; |
| 319 | if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0) |
| 320 | BUG(); |
| 321 | del_evtchn(u, evtchn); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 322 | return rc; |
| 323 | } |
| 324 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 325 | static void evtchn_unbind_from_user(struct per_user_data *u, |
| 326 | struct user_evtchn *evtchn) |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 327 | { |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 328 | int irq = irq_from_evtchn(evtchn->port); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 329 | |
Wei Liu | e7e44e4 | 2013-02-18 14:57:58 +0000 | [diff] [blame] | 330 | BUG_ON(irq < 0); |
| 331 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 332 | unbind_from_irqhandler(irq, evtchn); |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 333 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 334 | del_evtchn(u, evtchn); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 335 | } |
| 336 | |
| 337 | static long evtchn_ioctl(struct file *file, |
| 338 | unsigned int cmd, unsigned long arg) |
| 339 | { |
| 340 | int rc; |
| 341 | struct per_user_data *u = file->private_data; |
| 342 | void __user *uarg = (void __user *) arg; |
| 343 | |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 344 | /* Prevent bind from racing with unbind */ |
| 345 | mutex_lock(&u->bind_mutex); |
| 346 | |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 347 | switch (cmd) { |
| 348 | case IOCTL_EVTCHN_BIND_VIRQ: { |
| 349 | struct ioctl_evtchn_bind_virq bind; |
| 350 | struct evtchn_bind_virq bind_virq; |
| 351 | |
| 352 | rc = -EFAULT; |
| 353 | if (copy_from_user(&bind, uarg, sizeof(bind))) |
| 354 | break; |
| 355 | |
| 356 | bind_virq.virq = bind.virq; |
| 357 | bind_virq.vcpu = 0; |
| 358 | rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, |
| 359 | &bind_virq); |
| 360 | if (rc != 0) |
| 361 | break; |
| 362 | |
| 363 | rc = evtchn_bind_to_user(u, bind_virq.port); |
| 364 | if (rc == 0) |
| 365 | rc = bind_virq.port; |
| 366 | break; |
| 367 | } |
| 368 | |
| 369 | case IOCTL_EVTCHN_BIND_INTERDOMAIN: { |
| 370 | struct ioctl_evtchn_bind_interdomain bind; |
| 371 | struct evtchn_bind_interdomain bind_interdomain; |
| 372 | |
| 373 | rc = -EFAULT; |
| 374 | if (copy_from_user(&bind, uarg, sizeof(bind))) |
| 375 | break; |
| 376 | |
| 377 | bind_interdomain.remote_dom = bind.remote_domain; |
| 378 | bind_interdomain.remote_port = bind.remote_port; |
| 379 | rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain, |
| 380 | &bind_interdomain); |
| 381 | if (rc != 0) |
| 382 | break; |
| 383 | |
| 384 | rc = evtchn_bind_to_user(u, bind_interdomain.local_port); |
| 385 | if (rc == 0) |
| 386 | rc = bind_interdomain.local_port; |
| 387 | break; |
| 388 | } |
| 389 | |
| 390 | case IOCTL_EVTCHN_BIND_UNBOUND_PORT: { |
| 391 | struct ioctl_evtchn_bind_unbound_port bind; |
| 392 | struct evtchn_alloc_unbound alloc_unbound; |
| 393 | |
| 394 | rc = -EFAULT; |
| 395 | if (copy_from_user(&bind, uarg, sizeof(bind))) |
| 396 | break; |
| 397 | |
| 398 | alloc_unbound.dom = DOMID_SELF; |
| 399 | alloc_unbound.remote_dom = bind.remote_domain; |
| 400 | rc = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound, |
| 401 | &alloc_unbound); |
| 402 | if (rc != 0) |
| 403 | break; |
| 404 | |
| 405 | rc = evtchn_bind_to_user(u, alloc_unbound.port); |
| 406 | if (rc == 0) |
| 407 | rc = alloc_unbound.port; |
| 408 | break; |
| 409 | } |
| 410 | |
| 411 | case IOCTL_EVTCHN_UNBIND: { |
| 412 | struct ioctl_evtchn_unbind unbind; |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 413 | struct user_evtchn *evtchn; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 414 | |
| 415 | rc = -EFAULT; |
| 416 | if (copy_from_user(&unbind, uarg, sizeof(unbind))) |
| 417 | break; |
| 418 | |
| 419 | rc = -EINVAL; |
| 420 | if (unbind.port >= NR_EVENT_CHANNELS) |
| 421 | break; |
| 422 | |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 423 | rc = -ENOTCONN; |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 424 | evtchn = find_evtchn(u, unbind.port); |
| 425 | if (!evtchn) |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 426 | break; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 427 | |
Jeremy Fitzhardinge | 3f5e554 | 2010-05-28 15:28:27 -0700 | [diff] [blame] | 428 | disable_irq(irq_from_evtchn(unbind.port)); |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 429 | evtchn_unbind_from_user(u, evtchn); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 430 | rc = 0; |
| 431 | break; |
| 432 | } |
| 433 | |
| 434 | case IOCTL_EVTCHN_NOTIFY: { |
| 435 | struct ioctl_evtchn_notify notify; |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 436 | struct user_evtchn *evtchn; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 437 | |
| 438 | rc = -EFAULT; |
| 439 | if (copy_from_user(¬ify, uarg, sizeof(notify))) |
| 440 | break; |
| 441 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 442 | rc = -ENOTCONN; |
| 443 | evtchn = find_evtchn(u, notify.port); |
| 444 | if (evtchn) { |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 445 | notify_remote_via_evtchn(notify.port); |
| 446 | rc = 0; |
| 447 | } |
| 448 | break; |
| 449 | } |
| 450 | |
| 451 | case IOCTL_EVTCHN_RESET: { |
| 452 | /* Initialise the ring to empty. Clear errors. */ |
| 453 | mutex_lock(&u->ring_cons_mutex); |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 454 | spin_lock_irq(&u->ring_prod_lock); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 455 | u->ring_cons = u->ring_prod = u->ring_overflow = 0; |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 456 | spin_unlock_irq(&u->ring_prod_lock); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 457 | mutex_unlock(&u->ring_cons_mutex); |
| 458 | rc = 0; |
| 459 | break; |
| 460 | } |
| 461 | |
| 462 | default: |
| 463 | rc = -ENOSYS; |
| 464 | break; |
| 465 | } |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 466 | mutex_unlock(&u->bind_mutex); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 467 | |
| 468 | return rc; |
| 469 | } |
| 470 | |
| 471 | static unsigned int evtchn_poll(struct file *file, poll_table *wait) |
| 472 | { |
| 473 | unsigned int mask = POLLOUT | POLLWRNORM; |
| 474 | struct per_user_data *u = file->private_data; |
| 475 | |
| 476 | poll_wait(file, &u->evtchn_wait, wait); |
| 477 | if (u->ring_cons != u->ring_prod) |
| 478 | mask |= POLLIN | POLLRDNORM; |
| 479 | if (u->ring_overflow) |
| 480 | mask = POLLERR; |
| 481 | return mask; |
| 482 | } |
| 483 | |
| 484 | static int evtchn_fasync(int fd, struct file *filp, int on) |
| 485 | { |
| 486 | struct per_user_data *u = filp->private_data; |
| 487 | return fasync_helper(fd, filp, on, &u->evtchn_async_queue); |
| 488 | } |
| 489 | |
| 490 | static int evtchn_open(struct inode *inode, struct file *filp) |
| 491 | { |
| 492 | struct per_user_data *u; |
| 493 | |
| 494 | u = kzalloc(sizeof(*u), GFP_KERNEL); |
| 495 | if (u == NULL) |
| 496 | return -ENOMEM; |
| 497 | |
| 498 | u->name = kasprintf(GFP_KERNEL, "evtchn:%s", current->comm); |
| 499 | if (u->name == NULL) { |
| 500 | kfree(u); |
| 501 | return -ENOMEM; |
| 502 | } |
| 503 | |
| 504 | init_waitqueue_head(&u->evtchn_wait); |
| 505 | |
| 506 | u->ring = (evtchn_port_t *)__get_free_page(GFP_KERNEL); |
| 507 | if (u->ring == NULL) { |
| 508 | kfree(u->name); |
| 509 | kfree(u); |
| 510 | return -ENOMEM; |
| 511 | } |
| 512 | |
Jeremy Fitzhardinge | 0a4666b | 2009-02-12 13:03:24 -0800 | [diff] [blame] | 513 | mutex_init(&u->bind_mutex); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 514 | mutex_init(&u->ring_cons_mutex); |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 515 | spin_lock_init(&u->ring_prod_lock); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 516 | |
| 517 | filp->private_data = u; |
| 518 | |
Justin P. Mattock | 6eab04a | 2011-04-08 19:49:08 -0700 | [diff] [blame] | 519 | return nonseekable_open(inode, filp); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 520 | } |
| 521 | |
| 522 | static int evtchn_release(struct inode *inode, struct file *filp) |
| 523 | { |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 524 | struct per_user_data *u = filp->private_data; |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 525 | struct rb_node *node; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 526 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 527 | while ((node = u->evtchns.rb_node)) { |
| 528 | struct user_evtchn *evtchn; |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 529 | |
David Vrabel | 73cc4bb | 2013-07-19 15:52:00 +0100 | [diff] [blame] | 530 | evtchn = rb_entry(node, struct user_evtchn, node); |
| 531 | disable_irq(irq_from_evtchn(evtchn->port)); |
| 532 | evtchn_unbind_from_user(u, evtchn); |
Jeremy Fitzhardinge | 3f5e554 | 2010-05-28 15:28:27 -0700 | [diff] [blame] | 533 | } |
| 534 | |
David Vrabel | 179fbd5 | 2013-07-19 15:51:58 +0100 | [diff] [blame] | 535 | free_page((unsigned long)u->ring); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 536 | kfree(u->name); |
| 537 | kfree(u); |
| 538 | |
| 539 | return 0; |
| 540 | } |
| 541 | |
| 542 | static const struct file_operations evtchn_fops = { |
| 543 | .owner = THIS_MODULE, |
| 544 | .read = evtchn_read, |
| 545 | .write = evtchn_write, |
| 546 | .unlocked_ioctl = evtchn_ioctl, |
| 547 | .poll = evtchn_poll, |
| 548 | .fasync = evtchn_fasync, |
| 549 | .open = evtchn_open, |
| 550 | .release = evtchn_release, |
Jeremy Fitzhardinge | bc7fc5e | 2010-11-18 22:32:17 -0800 | [diff] [blame] | 551 | .llseek = no_llseek, |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 552 | }; |
| 553 | |
| 554 | static struct miscdevice evtchn_miscdev = { |
| 555 | .minor = MISC_DYNAMIC_MINOR, |
Bastian Blank | 376d908 | 2010-05-28 15:43:49 -0700 | [diff] [blame] | 556 | .name = "xen/evtchn", |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 557 | .fops = &evtchn_fops, |
| 558 | }; |
| 559 | static int __init evtchn_init(void) |
| 560 | { |
| 561 | int err; |
| 562 | |
| 563 | if (!xen_domain()) |
| 564 | return -ENODEV; |
| 565 | |
Wei Liu | 18283ea | 2013-02-18 14:57:59 +0000 | [diff] [blame] | 566 | /* Create '/dev/xen/evtchn'. */ |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 567 | err = misc_register(&evtchn_miscdev); |
| 568 | if (err != 0) { |
Joe Perches | 283c097 | 2013-06-28 03:21:41 -0700 | [diff] [blame] | 569 | pr_err("Could not register /dev/xen/evtchn\n"); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 570 | return err; |
| 571 | } |
| 572 | |
Joe Perches | 283c097 | 2013-06-28 03:21:41 -0700 | [diff] [blame] | 573 | pr_info("Event-channel device installed\n"); |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 574 | |
| 575 | return 0; |
| 576 | } |
| 577 | |
| 578 | static void __exit evtchn_cleanup(void) |
| 579 | { |
Ian Campbell | f711628 | 2009-02-06 19:21:19 -0800 | [diff] [blame] | 580 | misc_deregister(&evtchn_miscdev); |
| 581 | } |
| 582 | |
| 583 | module_init(evtchn_init); |
| 584 | module_exit(evtchn_cleanup); |
| 585 | |
| 586 | MODULE_LICENSE("GPL"); |