Commit | Line | Data |
---|---|---|
6e1819d6 RW |
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> | |
3592695c | 14 | #include <linux/reboot.h> |
6e1819d6 RW |
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> | |
97c7801c | 23 | #include <linux/console.h> |
e3920fb4 | 24 | #include <linux/cpu.h> |
7dfb7103 | 25 | #include <linux/freezer.h> |
6e1819d6 RW |
26 | |
27 | #include <asm/uaccess.h> | |
28 | ||
29 | #include "power.h" | |
30 | ||
31 | #define SNAPSHOT_MINOR 231 | |
32 | ||
33 | static struct snapshot_data { | |
34 | struct snapshot_handle handle; | |
35 | int swap; | |
36 | struct bitmap_page *bitmap; | |
37 | int mode; | |
38 | char frozen; | |
39 | char ready; | |
2b5b09b3 | 40 | char platform_suspend; |
6e1819d6 RW |
41 | } snapshot_state; |
42 | ||
43 | static atomic_t device_available = ATOMIC_INIT(1); | |
44 | ||
45 | static int snapshot_open(struct inode *inode, struct file *filp) | |
46 | { | |
47 | struct snapshot_data *data; | |
48 | ||
49 | if (!atomic_add_unless(&device_available, -1, 0)) | |
50 | return -EBUSY; | |
51 | ||
1525a2ad RW |
52 | if ((filp->f_flags & O_ACCMODE) == O_RDWR) { |
53 | atomic_inc(&device_available); | |
6e1819d6 | 54 | return -ENOSYS; |
1525a2ad RW |
55 | } |
56 | if(create_basic_memory_bitmaps()) { | |
57 | atomic_inc(&device_available); | |
74dfd666 | 58 | return -ENOMEM; |
1525a2ad | 59 | } |
6e1819d6 RW |
60 | nonseekable_open(inode, filp); |
61 | data = &snapshot_state; | |
62 | filp->private_data = data; | |
63 | memset(&data->handle, 0, sizeof(struct snapshot_handle)); | |
64 | if ((filp->f_flags & O_ACCMODE) == O_RDONLY) { | |
915bae9e | 65 | data->swap = swsusp_resume_device ? |
7bf23687 | 66 | swap_type_of(swsusp_resume_device, 0, NULL) : -1; |
6e1819d6 RW |
67 | data->mode = O_RDONLY; |
68 | } else { | |
69 | data->swap = -1; | |
70 | data->mode = O_WRONLY; | |
71 | } | |
72 | data->bitmap = NULL; | |
73 | data->frozen = 0; | |
74 | data->ready = 0; | |
2b5b09b3 | 75 | data->platform_suspend = 0; |
6e1819d6 RW |
76 | |
77 | return 0; | |
78 | } | |
79 | ||
80 | static int snapshot_release(struct inode *inode, struct file *filp) | |
81 | { | |
82 | struct snapshot_data *data; | |
83 | ||
84 | swsusp_free(); | |
74dfd666 | 85 | free_basic_memory_bitmaps(); |
6e1819d6 RW |
86 | data = filp->private_data; |
87 | free_all_swap_pages(data->swap, data->bitmap); | |
88 | free_bitmap(data->bitmap); | |
89 | if (data->frozen) { | |
a6d70980 | 90 | mutex_lock(&pm_mutex); |
6e1819d6 RW |
91 | thaw_processes(); |
92 | enable_nonboot_cpus(); | |
a6d70980 | 93 | mutex_unlock(&pm_mutex); |
6e1819d6 RW |
94 | } |
95 | atomic_inc(&device_available); | |
96 | return 0; | |
97 | } | |
98 | ||
99 | static ssize_t snapshot_read(struct file *filp, char __user *buf, | |
100 | size_t count, loff_t *offp) | |
101 | { | |
102 | struct snapshot_data *data; | |
103 | ssize_t res; | |
104 | ||
105 | data = filp->private_data; | |
106 | res = snapshot_read_next(&data->handle, count); | |
107 | if (res > 0) { | |
108 | if (copy_to_user(buf, data_of(data->handle), res)) | |
109 | res = -EFAULT; | |
110 | else | |
111 | *offp = data->handle.offset; | |
112 | } | |
113 | return res; | |
114 | } | |
115 | ||
116 | static ssize_t snapshot_write(struct file *filp, const char __user *buf, | |
117 | size_t count, loff_t *offp) | |
118 | { | |
119 | struct snapshot_data *data; | |
120 | ssize_t res; | |
121 | ||
122 | data = filp->private_data; | |
123 | res = snapshot_write_next(&data->handle, count); | |
124 | if (res > 0) { | |
125 | if (copy_from_user(data_of(data->handle), buf, res)) | |
126 | res = -EFAULT; | |
127 | else | |
128 | *offp = data->handle.offset; | |
129 | } | |
130 | return res; | |
131 | } | |
132 | ||
2b5b09b3 RW |
133 | static inline int platform_prepare(void) |
134 | { | |
135 | int error = 0; | |
136 | ||
137 | if (pm_ops && pm_ops->prepare) | |
138 | error = pm_ops->prepare(PM_SUSPEND_DISK); | |
139 | ||
140 | return error; | |
141 | } | |
142 | ||
143 | static inline void platform_finish(void) | |
144 | { | |
145 | if (pm_ops && pm_ops->finish) | |
146 | pm_ops->finish(PM_SUSPEND_DISK); | |
147 | } | |
148 | ||
149 | static inline int snapshot_suspend(int platform_suspend) | |
25913052 RW |
150 | { |
151 | int error; | |
152 | ||
153 | mutex_lock(&pm_mutex); | |
154 | /* Free memory before shutting down devices. */ | |
155 | error = swsusp_shrink_memory(); | |
156 | if (error) | |
157 | goto Finish; | |
158 | ||
2b5b09b3 RW |
159 | if (platform_suspend) { |
160 | error = platform_prepare(); | |
161 | if (error) | |
162 | goto Finish; | |
163 | } | |
25913052 RW |
164 | suspend_console(); |
165 | error = device_suspend(PMSG_FREEZE); | |
166 | if (error) | |
167 | goto Resume_devices; | |
168 | ||
169 | error = disable_nonboot_cpus(); | |
170 | if (!error) { | |
171 | in_suspend = 1; | |
172 | error = swsusp_suspend(); | |
173 | } | |
174 | enable_nonboot_cpus(); | |
175 | Resume_devices: | |
2b5b09b3 RW |
176 | if (platform_suspend) |
177 | platform_finish(); | |
178 | ||
25913052 RW |
179 | device_resume(); |
180 | resume_console(); | |
181 | Finish: | |
182 | mutex_unlock(&pm_mutex); | |
183 | return error; | |
184 | } | |
185 | ||
2b5b09b3 | 186 | static inline int snapshot_restore(int platform_suspend) |
25913052 RW |
187 | { |
188 | int error; | |
189 | ||
190 | mutex_lock(&pm_mutex); | |
191 | pm_prepare_console(); | |
2b5b09b3 RW |
192 | if (platform_suspend) { |
193 | error = platform_prepare(); | |
194 | if (error) | |
195 | goto Finish; | |
196 | } | |
25913052 RW |
197 | suspend_console(); |
198 | error = device_suspend(PMSG_PRETHAW); | |
199 | if (error) | |
200 | goto Resume_devices; | |
201 | ||
202 | error = disable_nonboot_cpus(); | |
203 | if (!error) | |
204 | error = swsusp_resume(); | |
205 | ||
206 | enable_nonboot_cpus(); | |
207 | Resume_devices: | |
2b5b09b3 RW |
208 | if (platform_suspend) |
209 | platform_finish(); | |
210 | ||
25913052 RW |
211 | device_resume(); |
212 | resume_console(); | |
2b5b09b3 | 213 | Finish: |
25913052 RW |
214 | pm_restore_console(); |
215 | mutex_unlock(&pm_mutex); | |
216 | return error; | |
217 | } | |
218 | ||
6e1819d6 RW |
219 | static int snapshot_ioctl(struct inode *inode, struct file *filp, |
220 | unsigned int cmd, unsigned long arg) | |
221 | { | |
222 | int error = 0; | |
223 | struct snapshot_data *data; | |
3aef83e0 RW |
224 | loff_t avail; |
225 | sector_t offset; | |
6e1819d6 RW |
226 | |
227 | if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC) | |
228 | return -ENOTTY; | |
229 | if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR) | |
230 | return -ENOTTY; | |
231 | if (!capable(CAP_SYS_ADMIN)) | |
232 | return -EPERM; | |
233 | ||
234 | data = filp->private_data; | |
235 | ||
236 | switch (cmd) { | |
237 | ||
238 | case SNAPSHOT_FREEZE: | |
239 | if (data->frozen) | |
240 | break; | |
a6d70980 | 241 | mutex_lock(&pm_mutex); |
25913052 RW |
242 | if (freeze_processes()) { |
243 | thaw_processes(); | |
244 | error = -EBUSY; | |
6e1819d6 | 245 | } |
a6d70980 | 246 | mutex_unlock(&pm_mutex); |
6e1819d6 RW |
247 | if (!error) |
248 | data->frozen = 1; | |
249 | break; | |
250 | ||
251 | case SNAPSHOT_UNFREEZE: | |
252 | if (!data->frozen) | |
253 | break; | |
a6d70980 | 254 | mutex_lock(&pm_mutex); |
6e1819d6 | 255 | thaw_processes(); |
a6d70980 | 256 | mutex_unlock(&pm_mutex); |
6e1819d6 RW |
257 | data->frozen = 0; |
258 | break; | |
259 | ||
260 | case SNAPSHOT_ATOMIC_SNAPSHOT: | |
261 | if (data->mode != O_RDONLY || !data->frozen || data->ready) { | |
262 | error = -EPERM; | |
263 | break; | |
264 | } | |
2b5b09b3 | 265 | error = snapshot_suspend(data->platform_suspend); |
6e1819d6 RW |
266 | if (!error) |
267 | error = put_user(in_suspend, (unsigned int __user *)arg); | |
268 | if (!error) | |
269 | data->ready = 1; | |
270 | break; | |
271 | ||
272 | case SNAPSHOT_ATOMIC_RESTORE: | |
8357376d | 273 | snapshot_write_finalize(&data->handle); |
6e1819d6 RW |
274 | if (data->mode != O_WRONLY || !data->frozen || |
275 | !snapshot_image_loaded(&data->handle)) { | |
276 | error = -EPERM; | |
277 | break; | |
278 | } | |
2b5b09b3 | 279 | error = snapshot_restore(data->platform_suspend); |
6e1819d6 RW |
280 | break; |
281 | ||
282 | case SNAPSHOT_FREE: | |
283 | swsusp_free(); | |
284 | memset(&data->handle, 0, sizeof(struct snapshot_handle)); | |
285 | data->ready = 0; | |
286 | break; | |
287 | ||
288 | case SNAPSHOT_SET_IMAGE_SIZE: | |
289 | image_size = arg; | |
290 | break; | |
291 | ||
292 | case SNAPSHOT_AVAIL_SWAP: | |
293 | avail = count_swap_pages(data->swap, 1); | |
294 | avail <<= PAGE_SHIFT; | |
295 | error = put_user(avail, (loff_t __user *)arg); | |
296 | break; | |
297 | ||
298 | case SNAPSHOT_GET_SWAP_PAGE: | |
299 | if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { | |
300 | error = -ENODEV; | |
301 | break; | |
302 | } | |
303 | if (!data->bitmap) { | |
304 | data->bitmap = alloc_bitmap(count_swap_pages(data->swap, 0)); | |
305 | if (!data->bitmap) { | |
306 | error = -ENOMEM; | |
307 | break; | |
308 | } | |
309 | } | |
3aef83e0 | 310 | offset = alloc_swapdev_block(data->swap, data->bitmap); |
6e1819d6 RW |
311 | if (offset) { |
312 | offset <<= PAGE_SHIFT; | |
3aef83e0 | 313 | error = put_user(offset, (sector_t __user *)arg); |
6e1819d6 RW |
314 | } else { |
315 | error = -ENOSPC; | |
316 | } | |
317 | break; | |
318 | ||
319 | case SNAPSHOT_FREE_SWAP_PAGES: | |
320 | if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { | |
321 | error = -ENODEV; | |
322 | break; | |
323 | } | |
324 | free_all_swap_pages(data->swap, data->bitmap); | |
325 | free_bitmap(data->bitmap); | |
326 | data->bitmap = NULL; | |
327 | break; | |
328 | ||
329 | case SNAPSHOT_SET_SWAP_FILE: | |
330 | if (!data->bitmap) { | |
331 | /* | |
332 | * User space encodes device types as two-byte values, | |
333 | * so we need to recode them | |
334 | */ | |
335 | if (old_decode_dev(arg)) { | |
7bf23687 RW |
336 | data->swap = swap_type_of(old_decode_dev(arg), |
337 | 0, NULL); | |
6e1819d6 RW |
338 | if (data->swap < 0) |
339 | error = -ENODEV; | |
340 | } else { | |
341 | data->swap = -1; | |
342 | error = -EINVAL; | |
343 | } | |
344 | } else { | |
345 | error = -EPERM; | |
346 | } | |
347 | break; | |
348 | ||
9b238205 | 349 | case SNAPSHOT_S2RAM: |
2b5b09b3 RW |
350 | if (!pm_ops) { |
351 | error = -ENOSYS; | |
352 | break; | |
353 | } | |
354 | ||
9b238205 LT |
355 | if (!data->frozen) { |
356 | error = -EPERM; | |
357 | break; | |
358 | } | |
359 | ||
a6d70980 | 360 | if (!mutex_trylock(&pm_mutex)) { |
9b238205 LT |
361 | error = -EBUSY; |
362 | break; | |
363 | } | |
364 | ||
365 | if (pm_ops->prepare) { | |
366 | error = pm_ops->prepare(PM_SUSPEND_MEM); | |
367 | if (error) | |
368 | goto OutS3; | |
369 | } | |
370 | ||
371 | /* Put devices to sleep */ | |
97c7801c | 372 | suspend_console(); |
9b238205 LT |
373 | error = device_suspend(PMSG_SUSPEND); |
374 | if (error) { | |
375 | printk(KERN_ERR "Failed to suspend some devices.\n"); | |
376 | } else { | |
93c9a7ff RW |
377 | error = disable_nonboot_cpus(); |
378 | if (!error) { | |
379 | /* Enter S3, system is already frozen */ | |
380 | suspend_enter(PM_SUSPEND_MEM); | |
381 | enable_nonboot_cpus(); | |
382 | } | |
9b238205 LT |
383 | /* Wake up devices */ |
384 | device_resume(); | |
385 | } | |
97c7801c | 386 | resume_console(); |
9b238205 LT |
387 | if (pm_ops->finish) |
388 | pm_ops->finish(PM_SUSPEND_MEM); | |
389 | ||
59a49335 | 390 | OutS3: |
a6d70980 | 391 | mutex_unlock(&pm_mutex); |
9b238205 LT |
392 | break; |
393 | ||
3592695c | 394 | case SNAPSHOT_PMOPS: |
2b5b09b3 RW |
395 | error = -EINVAL; |
396 | ||
3592695c SS |
397 | switch (arg) { |
398 | ||
399 | case PMOPS_PREPARE: | |
2b5b09b3 RW |
400 | if (pm_ops && pm_ops->enter) { |
401 | data->platform_suspend = 1; | |
402 | error = 0; | |
403 | } else { | |
404 | error = -ENOSYS; | |
3592695c SS |
405 | } |
406 | break; | |
407 | ||
408 | case PMOPS_ENTER: | |
2b5b09b3 RW |
409 | if (data->platform_suspend) { |
410 | kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK); | |
411 | error = pm_ops->enter(PM_SUSPEND_DISK); | |
436ce716 | 412 | error = 0; |
2b5b09b3 | 413 | } |
3592695c SS |
414 | break; |
415 | ||
416 | case PMOPS_FINISH: | |
2b5b09b3 RW |
417 | if (data->platform_suspend) |
418 | error = 0; | |
419 | ||
3592695c SS |
420 | break; |
421 | ||
422 | default: | |
423 | printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg); | |
3592695c SS |
424 | |
425 | } | |
426 | break; | |
427 | ||
37b2ba12 RW |
428 | case SNAPSHOT_SET_SWAP_AREA: |
429 | if (data->bitmap) { | |
430 | error = -EPERM; | |
431 | } else { | |
432 | struct resume_swap_area swap_area; | |
433 | dev_t swdev; | |
434 | ||
435 | error = copy_from_user(&swap_area, (void __user *)arg, | |
436 | sizeof(struct resume_swap_area)); | |
437 | if (error) { | |
438 | error = -EFAULT; | |
439 | break; | |
440 | } | |
441 | ||
442 | /* | |
443 | * User space encodes device types as two-byte values, | |
444 | * so we need to recode them | |
445 | */ | |
446 | swdev = old_decode_dev(swap_area.dev); | |
447 | if (swdev) { | |
448 | offset = swap_area.offset; | |
7bf23687 | 449 | data->swap = swap_type_of(swdev, offset, NULL); |
37b2ba12 RW |
450 | if (data->swap < 0) |
451 | error = -ENODEV; | |
452 | } else { | |
453 | data->swap = -1; | |
454 | error = -EINVAL; | |
455 | } | |
456 | } | |
457 | break; | |
458 | ||
6e1819d6 RW |
459 | default: |
460 | error = -ENOTTY; | |
461 | ||
462 | } | |
463 | ||
464 | return error; | |
465 | } | |
466 | ||
15ad7cdc | 467 | static const struct file_operations snapshot_fops = { |
6e1819d6 RW |
468 | .open = snapshot_open, |
469 | .release = snapshot_release, | |
470 | .read = snapshot_read, | |
471 | .write = snapshot_write, | |
472 | .llseek = no_llseek, | |
473 | .ioctl = snapshot_ioctl, | |
474 | }; | |
475 | ||
476 | static struct miscdevice snapshot_device = { | |
477 | .minor = SNAPSHOT_MINOR, | |
478 | .name = "snapshot", | |
479 | .fops = &snapshot_fops, | |
480 | }; | |
481 | ||
482 | static int __init snapshot_device_init(void) | |
483 | { | |
484 | return misc_register(&snapshot_device); | |
485 | }; | |
486 | ||
487 | device_initcall(snapshot_device_init); |