Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/power/user.c |
| 3 | * |
| 4 | * This file provides the user space interface for software suspend/resume. |
| 5 | * |
| 6 | * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> |
| 7 | * |
| 8 | * This file is released under the GPLv2. |
| 9 | * |
| 10 | */ |
| 11 | |
| 12 | #include <linux/suspend.h> |
| 13 | #include <linux/syscalls.h> |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame^] | 14 | #include <linux/reboot.h> |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 15 | #include <linux/string.h> |
| 16 | #include <linux/device.h> |
| 17 | #include <linux/miscdevice.h> |
| 18 | #include <linux/mm.h> |
| 19 | #include <linux/swap.h> |
| 20 | #include <linux/swapops.h> |
| 21 | #include <linux/pm.h> |
| 22 | #include <linux/fs.h> |
Rafael J. Wysocki | 97c7801 | 2006-10-11 01:20:45 -0700 | [diff] [blame] | 23 | #include <linux/console.h> |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 24 | #include <linux/cpu.h> |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 25 | |
| 26 | #include <asm/uaccess.h> |
| 27 | |
| 28 | #include "power.h" |
| 29 | |
| 30 | #define SNAPSHOT_MINOR 231 |
| 31 | |
| 32 | static struct snapshot_data { |
| 33 | struct snapshot_handle handle; |
| 34 | int swap; |
| 35 | struct bitmap_page *bitmap; |
| 36 | int mode; |
| 37 | char frozen; |
| 38 | char ready; |
| 39 | } snapshot_state; |
| 40 | |
| 41 | static atomic_t device_available = ATOMIC_INIT(1); |
| 42 | |
| 43 | static int snapshot_open(struct inode *inode, struct file *filp) |
| 44 | { |
| 45 | struct snapshot_data *data; |
| 46 | |
| 47 | if (!atomic_add_unless(&device_available, -1, 0)) |
| 48 | return -EBUSY; |
| 49 | |
| 50 | if ((filp->f_flags & O_ACCMODE) == O_RDWR) |
| 51 | return -ENOSYS; |
| 52 | |
| 53 | nonseekable_open(inode, filp); |
| 54 | data = &snapshot_state; |
| 55 | filp->private_data = data; |
| 56 | memset(&data->handle, 0, sizeof(struct snapshot_handle)); |
| 57 | if ((filp->f_flags & O_ACCMODE) == O_RDONLY) { |
| 58 | data->swap = swsusp_resume_device ? swap_type_of(swsusp_resume_device) : -1; |
| 59 | data->mode = O_RDONLY; |
| 60 | } else { |
| 61 | data->swap = -1; |
| 62 | data->mode = O_WRONLY; |
| 63 | } |
| 64 | data->bitmap = NULL; |
| 65 | data->frozen = 0; |
| 66 | data->ready = 0; |
| 67 | |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | static int snapshot_release(struct inode *inode, struct file *filp) |
| 72 | { |
| 73 | struct snapshot_data *data; |
| 74 | |
| 75 | swsusp_free(); |
| 76 | data = filp->private_data; |
| 77 | free_all_swap_pages(data->swap, data->bitmap); |
| 78 | free_bitmap(data->bitmap); |
| 79 | if (data->frozen) { |
| 80 | down(&pm_sem); |
| 81 | thaw_processes(); |
| 82 | enable_nonboot_cpus(); |
| 83 | up(&pm_sem); |
| 84 | } |
| 85 | atomic_inc(&device_available); |
| 86 | return 0; |
| 87 | } |
| 88 | |
| 89 | static ssize_t snapshot_read(struct file *filp, char __user *buf, |
| 90 | size_t count, loff_t *offp) |
| 91 | { |
| 92 | struct snapshot_data *data; |
| 93 | ssize_t res; |
| 94 | |
| 95 | data = filp->private_data; |
| 96 | res = snapshot_read_next(&data->handle, count); |
| 97 | if (res > 0) { |
| 98 | if (copy_to_user(buf, data_of(data->handle), res)) |
| 99 | res = -EFAULT; |
| 100 | else |
| 101 | *offp = data->handle.offset; |
| 102 | } |
| 103 | return res; |
| 104 | } |
| 105 | |
| 106 | static ssize_t snapshot_write(struct file *filp, const char __user *buf, |
| 107 | size_t count, loff_t *offp) |
| 108 | { |
| 109 | struct snapshot_data *data; |
| 110 | ssize_t res; |
| 111 | |
| 112 | data = filp->private_data; |
| 113 | res = snapshot_write_next(&data->handle, count); |
| 114 | if (res > 0) { |
| 115 | if (copy_from_user(data_of(data->handle), buf, res)) |
| 116 | res = -EFAULT; |
| 117 | else |
| 118 | *offp = data->handle.offset; |
| 119 | } |
| 120 | return res; |
| 121 | } |
| 122 | |
| 123 | static int snapshot_ioctl(struct inode *inode, struct file *filp, |
| 124 | unsigned int cmd, unsigned long arg) |
| 125 | { |
| 126 | int error = 0; |
| 127 | struct snapshot_data *data; |
| 128 | loff_t offset, avail; |
| 129 | |
| 130 | if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC) |
| 131 | return -ENOTTY; |
| 132 | if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR) |
| 133 | return -ENOTTY; |
| 134 | if (!capable(CAP_SYS_ADMIN)) |
| 135 | return -EPERM; |
| 136 | |
| 137 | data = filp->private_data; |
| 138 | |
| 139 | switch (cmd) { |
| 140 | |
| 141 | case SNAPSHOT_FREEZE: |
| 142 | if (data->frozen) |
| 143 | break; |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 144 | down(&pm_sem); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 145 | error = disable_nonboot_cpus(); |
| 146 | if (!error) { |
| 147 | error = freeze_processes(); |
| 148 | if (error) { |
| 149 | thaw_processes(); |
Rafael J. Wysocki | 5c339d4 | 2006-10-06 22:19:44 -0700 | [diff] [blame] | 150 | enable_nonboot_cpus(); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 151 | error = -EBUSY; |
| 152 | } |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 153 | } |
| 154 | up(&pm_sem); |
| 155 | if (!error) |
| 156 | data->frozen = 1; |
| 157 | break; |
| 158 | |
| 159 | case SNAPSHOT_UNFREEZE: |
| 160 | if (!data->frozen) |
| 161 | break; |
| 162 | down(&pm_sem); |
| 163 | thaw_processes(); |
| 164 | enable_nonboot_cpus(); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 165 | up(&pm_sem); |
| 166 | data->frozen = 0; |
| 167 | break; |
| 168 | |
| 169 | case SNAPSHOT_ATOMIC_SNAPSHOT: |
| 170 | if (data->mode != O_RDONLY || !data->frozen || data->ready) { |
| 171 | error = -EPERM; |
| 172 | break; |
| 173 | } |
| 174 | down(&pm_sem); |
| 175 | /* Free memory before shutting down devices. */ |
| 176 | error = swsusp_shrink_memory(); |
| 177 | if (!error) { |
Rafael J. Wysocki | 97c7801 | 2006-10-11 01:20:45 -0700 | [diff] [blame] | 178 | suspend_console(); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 179 | error = device_suspend(PMSG_FREEZE); |
| 180 | if (!error) { |
| 181 | in_suspend = 1; |
| 182 | error = swsusp_suspend(); |
| 183 | device_resume(); |
| 184 | } |
Rafael J. Wysocki | 97c7801 | 2006-10-11 01:20:45 -0700 | [diff] [blame] | 185 | resume_console(); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 186 | } |
| 187 | up(&pm_sem); |
| 188 | if (!error) |
| 189 | error = put_user(in_suspend, (unsigned int __user *)arg); |
| 190 | if (!error) |
| 191 | data->ready = 1; |
| 192 | break; |
| 193 | |
| 194 | case SNAPSHOT_ATOMIC_RESTORE: |
| 195 | if (data->mode != O_WRONLY || !data->frozen || |
| 196 | !snapshot_image_loaded(&data->handle)) { |
| 197 | error = -EPERM; |
| 198 | break; |
| 199 | } |
Rafael J. Wysocki | 940864d | 2006-09-25 23:32:55 -0700 | [diff] [blame] | 200 | snapshot_free_unused_memory(&data->handle); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 201 | down(&pm_sem); |
| 202 | pm_prepare_console(); |
Rafael J. Wysocki | 97c7801 | 2006-10-11 01:20:45 -0700 | [diff] [blame] | 203 | suspend_console(); |
David Brownell | f1cc0a8 | 2006-08-14 23:11:08 -0700 | [diff] [blame] | 204 | error = device_suspend(PMSG_PRETHAW); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 205 | if (!error) { |
| 206 | error = swsusp_resume(); |
| 207 | device_resume(); |
| 208 | } |
Rafael J. Wysocki | 97c7801 | 2006-10-11 01:20:45 -0700 | [diff] [blame] | 209 | resume_console(); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 210 | pm_restore_console(); |
| 211 | up(&pm_sem); |
| 212 | break; |
| 213 | |
| 214 | case SNAPSHOT_FREE: |
| 215 | swsusp_free(); |
| 216 | memset(&data->handle, 0, sizeof(struct snapshot_handle)); |
| 217 | data->ready = 0; |
| 218 | break; |
| 219 | |
| 220 | case SNAPSHOT_SET_IMAGE_SIZE: |
| 221 | image_size = arg; |
| 222 | break; |
| 223 | |
| 224 | case SNAPSHOT_AVAIL_SWAP: |
| 225 | avail = count_swap_pages(data->swap, 1); |
| 226 | avail <<= PAGE_SHIFT; |
| 227 | error = put_user(avail, (loff_t __user *)arg); |
| 228 | break; |
| 229 | |
| 230 | case SNAPSHOT_GET_SWAP_PAGE: |
| 231 | if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { |
| 232 | error = -ENODEV; |
| 233 | break; |
| 234 | } |
| 235 | if (!data->bitmap) { |
| 236 | data->bitmap = alloc_bitmap(count_swap_pages(data->swap, 0)); |
| 237 | if (!data->bitmap) { |
| 238 | error = -ENOMEM; |
| 239 | break; |
| 240 | } |
| 241 | } |
| 242 | offset = alloc_swap_page(data->swap, data->bitmap); |
| 243 | if (offset) { |
| 244 | offset <<= PAGE_SHIFT; |
| 245 | error = put_user(offset, (loff_t __user *)arg); |
| 246 | } else { |
| 247 | error = -ENOSPC; |
| 248 | } |
| 249 | break; |
| 250 | |
| 251 | case SNAPSHOT_FREE_SWAP_PAGES: |
| 252 | if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { |
| 253 | error = -ENODEV; |
| 254 | break; |
| 255 | } |
| 256 | free_all_swap_pages(data->swap, data->bitmap); |
| 257 | free_bitmap(data->bitmap); |
| 258 | data->bitmap = NULL; |
| 259 | break; |
| 260 | |
| 261 | case SNAPSHOT_SET_SWAP_FILE: |
| 262 | if (!data->bitmap) { |
| 263 | /* |
| 264 | * User space encodes device types as two-byte values, |
| 265 | * so we need to recode them |
| 266 | */ |
| 267 | if (old_decode_dev(arg)) { |
| 268 | data->swap = swap_type_of(old_decode_dev(arg)); |
| 269 | if (data->swap < 0) |
| 270 | error = -ENODEV; |
| 271 | } else { |
| 272 | data->swap = -1; |
| 273 | error = -EINVAL; |
| 274 | } |
| 275 | } else { |
| 276 | error = -EPERM; |
| 277 | } |
| 278 | break; |
| 279 | |
Luca Tettamanti | 9b23820 | 2006-03-23 03:00:09 -0800 | [diff] [blame] | 280 | case SNAPSHOT_S2RAM: |
| 281 | if (!data->frozen) { |
| 282 | error = -EPERM; |
| 283 | break; |
| 284 | } |
| 285 | |
| 286 | if (down_trylock(&pm_sem)) { |
| 287 | error = -EBUSY; |
| 288 | break; |
| 289 | } |
| 290 | |
| 291 | if (pm_ops->prepare) { |
| 292 | error = pm_ops->prepare(PM_SUSPEND_MEM); |
| 293 | if (error) |
| 294 | goto OutS3; |
| 295 | } |
| 296 | |
| 297 | /* Put devices to sleep */ |
Rafael J. Wysocki | 97c7801 | 2006-10-11 01:20:45 -0700 | [diff] [blame] | 298 | suspend_console(); |
Luca Tettamanti | 9b23820 | 2006-03-23 03:00:09 -0800 | [diff] [blame] | 299 | error = device_suspend(PMSG_SUSPEND); |
| 300 | if (error) { |
| 301 | printk(KERN_ERR "Failed to suspend some devices.\n"); |
| 302 | } else { |
| 303 | /* Enter S3, system is already frozen */ |
| 304 | suspend_enter(PM_SUSPEND_MEM); |
| 305 | |
| 306 | /* Wake up devices */ |
| 307 | device_resume(); |
| 308 | } |
Rafael J. Wysocki | 97c7801 | 2006-10-11 01:20:45 -0700 | [diff] [blame] | 309 | resume_console(); |
Luca Tettamanti | 9b23820 | 2006-03-23 03:00:09 -0800 | [diff] [blame] | 310 | if (pm_ops->finish) |
| 311 | pm_ops->finish(PM_SUSPEND_MEM); |
| 312 | |
| 313 | OutS3: |
| 314 | up(&pm_sem); |
| 315 | break; |
| 316 | |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame^] | 317 | case SNAPSHOT_PMOPS: |
| 318 | switch (arg) { |
| 319 | |
| 320 | case PMOPS_PREPARE: |
| 321 | if (pm_ops->prepare) { |
| 322 | error = pm_ops->prepare(PM_SUSPEND_DISK); |
| 323 | } |
| 324 | break; |
| 325 | |
| 326 | case PMOPS_ENTER: |
| 327 | kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK); |
| 328 | error = pm_ops->enter(PM_SUSPEND_DISK); |
| 329 | break; |
| 330 | |
| 331 | case PMOPS_FINISH: |
| 332 | if (pm_ops && pm_ops->finish) { |
| 333 | pm_ops->finish(PM_SUSPEND_DISK); |
| 334 | } |
| 335 | break; |
| 336 | |
| 337 | default: |
| 338 | printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg); |
| 339 | error = -EINVAL; |
| 340 | |
| 341 | } |
| 342 | break; |
| 343 | |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 344 | default: |
| 345 | error = -ENOTTY; |
| 346 | |
| 347 | } |
| 348 | |
| 349 | return error; |
| 350 | } |
| 351 | |
| 352 | static struct file_operations snapshot_fops = { |
| 353 | .open = snapshot_open, |
| 354 | .release = snapshot_release, |
| 355 | .read = snapshot_read, |
| 356 | .write = snapshot_write, |
| 357 | .llseek = no_llseek, |
| 358 | .ioctl = snapshot_ioctl, |
| 359 | }; |
| 360 | |
| 361 | static struct miscdevice snapshot_device = { |
| 362 | .minor = SNAPSHOT_MINOR, |
| 363 | .name = "snapshot", |
| 364 | .fops = &snapshot_fops, |
| 365 | }; |
| 366 | |
| 367 | static int __init snapshot_device_init(void) |
| 368 | { |
| 369 | return misc_register(&snapshot_device); |
| 370 | }; |
| 371 | |
| 372 | device_initcall(snapshot_device_init); |