PM / Hibernate: Really deprecate deprecated user ioctls
[linux-2.6.git] / kernel / power / user.c
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>
14 #include <linux/reboot.h>
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>
23 #include <linux/console.h>
24 #include <linux/cpu.h>
25 #include <linux/freezer.h>
26 #include <scsi/scsi_scan.h>
27
28 #include <asm/uaccess.h>
29
30 #include "power.h"
31
32 /*
33  * NOTE: The SNAPSHOT_SET_SWAP_FILE and SNAPSHOT_PMOPS ioctls are obsolete and
34  * will be removed in the future.  They are only preserved here for
35  * compatibility with existing userland utilities.
36  */
37 #define SNAPSHOT_SET_SWAP_FILE  _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
38 #define SNAPSHOT_PMOPS          _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
39
40 #define PMOPS_PREPARE   1
41 #define PMOPS_ENTER     2
42 #define PMOPS_FINISH    3
43
44 /*
45  * NOTE: The following ioctl definitions are wrong and have been replaced with
46  * correct ones.  They are only preserved here for compatibility with existing
47  * userland utilities and will be removed in the future.
48  */
49 #define SNAPSHOT_ATOMIC_SNAPSHOT        _IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
50 #define SNAPSHOT_SET_IMAGE_SIZE         _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
51 #define SNAPSHOT_AVAIL_SWAP             _IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
52 #define SNAPSHOT_GET_SWAP_PAGE          _IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
53
54
55 #define SNAPSHOT_MINOR  231
56
57 static struct snapshot_data {
58         struct snapshot_handle handle;
59         int swap;
60         int mode;
61         char frozen;
62         char ready;
63         char platform_support;
64 } snapshot_state;
65
66 atomic_t snapshot_device_available = ATOMIC_INIT(1);
67
68 static int snapshot_open(struct inode *inode, struct file *filp)
69 {
70         struct snapshot_data *data;
71         int error;
72
73         mutex_lock(&pm_mutex);
74
75         if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
76                 error = -EBUSY;
77                 goto Unlock;
78         }
79
80         if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
81                 atomic_inc(&snapshot_device_available);
82                 error = -ENOSYS;
83                 goto Unlock;
84         }
85         if(create_basic_memory_bitmaps()) {
86                 atomic_inc(&snapshot_device_available);
87                 error = -ENOMEM;
88                 goto Unlock;
89         }
90         nonseekable_open(inode, filp);
91         data = &snapshot_state;
92         filp->private_data = data;
93         memset(&data->handle, 0, sizeof(struct snapshot_handle));
94         if ((filp->f_flags & O_ACCMODE) == O_RDONLY) {
95                 /* Hibernating.  The image device should be accessible. */
96                 data->swap = swsusp_resume_device ?
97                         swap_type_of(swsusp_resume_device, 0, NULL) : -1;
98                 data->mode = O_RDONLY;
99                 error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
100                 if (error)
101                         pm_notifier_call_chain(PM_POST_HIBERNATION);
102         } else {
103                 /*
104                  * Resuming.  We may need to wait for the image device to
105                  * appear.
106                  */
107                 wait_for_device_probe();
108                 scsi_complete_async_scans();
109
110                 data->swap = -1;
111                 data->mode = O_WRONLY;
112                 error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
113                 if (error)
114                         pm_notifier_call_chain(PM_POST_RESTORE);
115         }
116         if (error)
117                 atomic_inc(&snapshot_device_available);
118         data->frozen = 0;
119         data->ready = 0;
120         data->platform_support = 0;
121
122  Unlock:
123         mutex_unlock(&pm_mutex);
124
125         return error;
126 }
127
128 static int snapshot_release(struct inode *inode, struct file *filp)
129 {
130         struct snapshot_data *data;
131
132         mutex_lock(&pm_mutex);
133
134         swsusp_free();
135         free_basic_memory_bitmaps();
136         data = filp->private_data;
137         free_all_swap_pages(data->swap);
138         if (data->frozen)
139                 thaw_processes();
140         pm_notifier_call_chain(data->mode == O_WRONLY ?
141                         PM_POST_HIBERNATION : PM_POST_RESTORE);
142         atomic_inc(&snapshot_device_available);
143
144         mutex_unlock(&pm_mutex);
145
146         return 0;
147 }
148
149 static ssize_t snapshot_read(struct file *filp, char __user *buf,
150                              size_t count, loff_t *offp)
151 {
152         struct snapshot_data *data;
153         ssize_t res;
154
155         mutex_lock(&pm_mutex);
156
157         data = filp->private_data;
158         if (!data->ready) {
159                 res = -ENODATA;
160                 goto Unlock;
161         }
162         res = snapshot_read_next(&data->handle, count);
163         if (res > 0) {
164                 if (copy_to_user(buf, data_of(data->handle), res))
165                         res = -EFAULT;
166                 else
167                         *offp = data->handle.offset;
168         }
169
170  Unlock:
171         mutex_unlock(&pm_mutex);
172
173         return res;
174 }
175
176 static ssize_t snapshot_write(struct file *filp, const char __user *buf,
177                               size_t count, loff_t *offp)
178 {
179         struct snapshot_data *data;
180         ssize_t res;
181
182         mutex_lock(&pm_mutex);
183
184         data = filp->private_data;
185         res = snapshot_write_next(&data->handle, count);
186         if (res > 0) {
187                 if (copy_from_user(data_of(data->handle), buf, res))
188                         res = -EFAULT;
189                 else
190                         *offp = data->handle.offset;
191         }
192
193         mutex_unlock(&pm_mutex);
194
195         return res;
196 }
197
198 static void snapshot_deprecated_ioctl(unsigned int cmd)
199 {
200         if (printk_ratelimit())
201                 printk(KERN_NOTICE "%pf: ioctl '%.8x' is deprecated and will "
202                                 "be removed soon, update your suspend-to-disk "
203                                 "utilities\n",
204                                 __builtin_return_address(0), cmd);
205 }
206
207 static long snapshot_ioctl(struct file *filp, unsigned int cmd,
208                                                         unsigned long arg)
209 {
210         int error = 0;
211         struct snapshot_data *data;
212         loff_t size;
213         sector_t offset;
214
215         if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
216                 return -ENOTTY;
217         if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR)
218                 return -ENOTTY;
219         if (!capable(CAP_SYS_ADMIN))
220                 return -EPERM;
221
222         if (!mutex_trylock(&pm_mutex))
223                 return -EBUSY;
224
225         data = filp->private_data;
226
227         switch (cmd) {
228
229         case SNAPSHOT_FREEZE:
230                 if (data->frozen)
231                         break;
232
233                 printk("Syncing filesystems ... ");
234                 sys_sync();
235                 printk("done.\n");
236
237                 error = usermodehelper_disable();
238                 if (error)
239                         break;
240
241                 error = freeze_processes();
242                 if (error) {
243                         thaw_processes();
244                         usermodehelper_enable();
245                 }
246                 if (!error)
247                         data->frozen = 1;
248                 break;
249
250         case SNAPSHOT_UNFREEZE:
251                 if (!data->frozen || data->ready)
252                         break;
253                 thaw_processes();
254                 usermodehelper_enable();
255                 data->frozen = 0;
256                 break;
257
258         case SNAPSHOT_ATOMIC_SNAPSHOT:
259                 snapshot_deprecated_ioctl(cmd);
260         case SNAPSHOT_CREATE_IMAGE:
261                 if (data->mode != O_RDONLY || !data->frozen  || data->ready) {
262                         error = -EPERM;
263                         break;
264                 }
265                 error = hibernation_snapshot(data->platform_support);
266                 if (!error)
267                         error = put_user(in_suspend, (int __user *)arg);
268                 if (!error)
269                         data->ready = 1;
270                 break;
271
272         case SNAPSHOT_ATOMIC_RESTORE:
273                 snapshot_write_finalize(&data->handle);
274                 if (data->mode != O_WRONLY || !data->frozen ||
275                     !snapshot_image_loaded(&data->handle)) {
276                         error = -EPERM;
277                         break;
278                 }
279                 error = hibernation_restore(data->platform_support);
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                 snapshot_deprecated_ioctl(cmd);
290         case SNAPSHOT_PREF_IMAGE_SIZE:
291                 image_size = arg;
292                 break;
293
294         case SNAPSHOT_GET_IMAGE_SIZE:
295                 if (!data->ready) {
296                         error = -ENODATA;
297                         break;
298                 }
299                 size = snapshot_get_image_size();
300                 size <<= PAGE_SHIFT;
301                 error = put_user(size, (loff_t __user *)arg);
302                 break;
303
304         case SNAPSHOT_AVAIL_SWAP:
305                 snapshot_deprecated_ioctl(cmd);
306         case SNAPSHOT_AVAIL_SWAP_SIZE:
307                 size = count_swap_pages(data->swap, 1);
308                 size <<= PAGE_SHIFT;
309                 error = put_user(size, (loff_t __user *)arg);
310                 break;
311
312         case SNAPSHOT_GET_SWAP_PAGE:
313                 snapshot_deprecated_ioctl(cmd);
314         case SNAPSHOT_ALLOC_SWAP_PAGE:
315                 if (data->swap < 0 || data->swap >= MAX_SWAPFILES) {
316                         error = -ENODEV;
317                         break;
318                 }
319                 offset = alloc_swapdev_block(data->swap);
320                 if (offset) {
321                         offset <<= PAGE_SHIFT;
322                         error = put_user(offset, (loff_t __user *)arg);
323                 } else {
324                         error = -ENOSPC;
325                 }
326                 break;
327
328         case SNAPSHOT_FREE_SWAP_PAGES:
329                 if (data->swap < 0 || data->swap >= MAX_SWAPFILES) {
330                         error = -ENODEV;
331                         break;
332                 }
333                 free_all_swap_pages(data->swap);
334                 break;
335
336         case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */
337                 snapshot_deprecated_ioctl(cmd);
338                 if (!swsusp_swap_in_use()) {
339                         /*
340                          * User space encodes device types as two-byte values,
341                          * so we need to recode them
342                          */
343                         if (old_decode_dev(arg)) {
344                                 data->swap = swap_type_of(old_decode_dev(arg),
345                                                         0, NULL);
346                                 if (data->swap < 0)
347                                         error = -ENODEV;
348                         } else {
349                                 data->swap = -1;
350                                 error = -EINVAL;
351                         }
352                 } else {
353                         error = -EPERM;
354                 }
355                 break;
356
357         case SNAPSHOT_S2RAM:
358                 if (!data->frozen) {
359                         error = -EPERM;
360                         break;
361                 }
362                 /*
363                  * Tasks are frozen and the notifiers have been called with
364                  * PM_HIBERNATION_PREPARE
365                  */
366                 error = suspend_devices_and_enter(PM_SUSPEND_MEM);
367                 break;
368
369         case SNAPSHOT_PLATFORM_SUPPORT:
370                 data->platform_support = !!arg;
371                 break;
372
373         case SNAPSHOT_POWER_OFF:
374                 if (data->platform_support)
375                         error = hibernation_platform_enter();
376                 break;
377
378         case SNAPSHOT_PMOPS: /* This ioctl is deprecated */
379                 snapshot_deprecated_ioctl(cmd);
380                 error = -EINVAL;
381
382                 switch (arg) {
383
384                 case PMOPS_PREPARE:
385                         data->platform_support = 1;
386                         error = 0;
387                         break;
388
389                 case PMOPS_ENTER:
390                         if (data->platform_support)
391                                 error = hibernation_platform_enter();
392                         break;
393
394                 case PMOPS_FINISH:
395                         if (data->platform_support)
396                                 error = 0;
397                         break;
398
399                 default:
400                         printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg);
401
402                 }
403                 break;
404
405         case SNAPSHOT_SET_SWAP_AREA:
406                 if (swsusp_swap_in_use()) {
407                         error = -EPERM;
408                 } else {
409                         struct resume_swap_area swap_area;
410                         dev_t swdev;
411
412                         error = copy_from_user(&swap_area, (void __user *)arg,
413                                         sizeof(struct resume_swap_area));
414                         if (error) {
415                                 error = -EFAULT;
416                                 break;
417                         }
418
419                         /*
420                          * User space encodes device types as two-byte values,
421                          * so we need to recode them
422                          */
423                         swdev = old_decode_dev(swap_area.dev);
424                         if (swdev) {
425                                 offset = swap_area.offset;
426                                 data->swap = swap_type_of(swdev, offset, NULL);
427                                 if (data->swap < 0)
428                                         error = -ENODEV;
429                         } else {
430                                 data->swap = -1;
431                                 error = -EINVAL;
432                         }
433                 }
434                 break;
435
436         default:
437                 error = -ENOTTY;
438
439         }
440
441         mutex_unlock(&pm_mutex);
442
443         return error;
444 }
445
446 static const struct file_operations snapshot_fops = {
447         .open = snapshot_open,
448         .release = snapshot_release,
449         .read = snapshot_read,
450         .write = snapshot_write,
451         .llseek = no_llseek,
452         .unlocked_ioctl = snapshot_ioctl,
453 };
454
455 static struct miscdevice snapshot_device = {
456         .minor = SNAPSHOT_MINOR,
457         .name = "snapshot",
458         .fops = &snapshot_fops,
459 };
460
461 static int __init snapshot_device_init(void)
462 {
463         return misc_register(&snapshot_device);
464 };
465
466 device_initcall(snapshot_device_init);