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