1/* SPDX-License-Identifier: GPL-2.0 */
2#include <linux/suspend.h>
3#include <linux/suspend_ioctls.h>
4#include <linux/utsname.h>
5#include <linux/freezer.h>
6#include <linux/compiler.h>
7#include <linux/cpu.h>
8#include <linux/cpuidle.h>
9
10struct swsusp_info {
11 struct new_utsname uts;
12 u32 version_code;
13 unsigned long num_physpages;
14 int cpus;
15 unsigned long image_pages;
16 unsigned long pages;
17 unsigned long size;
18} __aligned(PAGE_SIZE);
19
20#ifdef CONFIG_HIBERNATION
21/* kernel/power/snapshot.c */
22extern void __init hibernate_reserved_size_init(void);
23extern void __init hibernate_image_size_init(void);
24
25#ifdef CONFIG_ARCH_HIBERNATION_HEADER
26/* Maximum size of architecture specific data in a hibernation header */
27#define MAX_ARCH_HEADER_SIZE (sizeof(struct new_utsname) + 4)
28
29static inline int init_header_complete(struct swsusp_info *info)
30{
31 return arch_hibernation_header_save(addr: info, MAX_ARCH_HEADER_SIZE);
32}
33
34static inline const char *check_image_kernel(struct swsusp_info *info)
35{
36 return arch_hibernation_header_restore(addr: info) ?
37 "architecture specific data" : NULL;
38}
39#endif /* CONFIG_ARCH_HIBERNATION_HEADER */
40
41/*
42 * Keep some memory free so that I/O operations can succeed without paging
43 * [Might this be more than 4 MB?]
44 */
45#define PAGES_FOR_IO ((4096 * 1024) >> PAGE_SHIFT)
46
47/*
48 * Keep 1 MB of memory free so that device drivers can allocate some pages in
49 * their .suspend() routines without breaking the suspend to disk.
50 */
51#define SPARE_PAGES ((1024 * 1024) >> PAGE_SHIFT)
52
53asmlinkage int swsusp_save(void);
54
55/* kernel/power/hibernate.c */
56extern bool freezer_test_done;
57
58extern int hibernation_snapshot(int platform_mode);
59extern int hibernation_restore(int platform_mode);
60extern int hibernation_platform_enter(void);
61
62#ifdef CONFIG_STRICT_KERNEL_RWX
63/* kernel/power/snapshot.c */
64extern void enable_restore_image_protection(void);
65#else
66static inline void enable_restore_image_protection(void) {}
67#endif /* CONFIG_STRICT_KERNEL_RWX */
68
69#else /* !CONFIG_HIBERNATION */
70
71static inline void hibernate_reserved_size_init(void) {}
72static inline void hibernate_image_size_init(void) {}
73#endif /* !CONFIG_HIBERNATION */
74
75#define power_attr(_name) \
76static struct kobj_attribute _name##_attr = { \
77 .attr = { \
78 .name = __stringify(_name), \
79 .mode = 0644, \
80 }, \
81 .show = _name##_show, \
82 .store = _name##_store, \
83}
84
85#define power_attr_ro(_name) \
86static struct kobj_attribute _name##_attr = { \
87 .attr = { \
88 .name = __stringify(_name), \
89 .mode = S_IRUGO, \
90 }, \
91 .show = _name##_show, \
92}
93
94/* Preferred image size in bytes (default 500 MB) */
95extern unsigned long image_size;
96/* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
97extern unsigned long reserved_size;
98extern int in_suspend;
99extern dev_t swsusp_resume_device;
100extern sector_t swsusp_resume_block;
101
102extern int create_basic_memory_bitmaps(void);
103extern void free_basic_memory_bitmaps(void);
104extern int hibernate_preallocate_memory(void);
105
106extern void clear_or_poison_free_pages(void);
107
108/**
109 * Auxiliary structure used for reading the snapshot image data and
110 * metadata from and writing them to the list of page backup entries
111 * (PBEs) which is the main data structure of swsusp.
112 *
113 * Using struct snapshot_handle we can transfer the image, including its
114 * metadata, as a continuous sequence of bytes with the help of
115 * snapshot_read_next() and snapshot_write_next().
116 *
117 * The code that writes the image to a storage or transfers it to
118 * the user land is required to use snapshot_read_next() for this
119 * purpose and it should not make any assumptions regarding the internal
120 * structure of the image. Similarly, the code that reads the image from
121 * a storage or transfers it from the user land is required to use
122 * snapshot_write_next().
123 *
124 * This may allow us to change the internal structure of the image
125 * in the future with considerably less effort.
126 */
127
128struct snapshot_handle {
129 unsigned int cur; /* number of the block of PAGE_SIZE bytes the
130 * next operation will refer to (ie. current)
131 */
132 void *buffer; /* address of the block to read from
133 * or write to
134 */
135 int sync_read; /* Set to one to notify the caller of
136 * snapshot_write_next() that it may
137 * need to call wait_on_bio_chain()
138 */
139};
140
141/* This macro returns the address from/to which the caller of
142 * snapshot_read_next()/snapshot_write_next() is allowed to
143 * read/write data after the function returns
144 */
145#define data_of(handle) ((handle).buffer)
146
147extern unsigned int snapshot_additional_pages(struct zone *zone);
148extern unsigned long snapshot_get_image_size(void);
149extern int snapshot_read_next(struct snapshot_handle *handle);
150extern int snapshot_write_next(struct snapshot_handle *handle);
151extern void snapshot_write_finalize(struct snapshot_handle *handle);
152extern int snapshot_image_loaded(struct snapshot_handle *handle);
153
154extern bool hibernate_acquire(void);
155extern void hibernate_release(void);
156
157extern sector_t alloc_swapdev_block(int swap);
158extern void free_all_swap_pages(int swap);
159extern int swsusp_swap_in_use(void);
160
161/*
162 * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
163 * the image header.
164 */
165#define SF_PLATFORM_MODE 1
166#define SF_NOCOMPRESS_MODE 2
167#define SF_CRC32_MODE 4
168#define SF_HW_SIG 8
169
170/* kernel/power/hibernate.c */
171int swsusp_check(bool exclusive);
172extern void swsusp_free(void);
173extern int swsusp_read(unsigned int *flags_p);
174extern int swsusp_write(unsigned int flags);
175void swsusp_close(void);
176#ifdef CONFIG_SUSPEND
177extern int swsusp_unmark(void);
178#endif
179
180struct __kernel_old_timeval;
181/* kernel/power/swsusp.c */
182extern void swsusp_show_speed(ktime_t, ktime_t, unsigned int, char *);
183
184#ifdef CONFIG_SUSPEND
185/* kernel/power/suspend.c */
186extern const char * const pm_labels[];
187extern const char *pm_states[];
188extern const char *mem_sleep_states[];
189
190extern int suspend_devices_and_enter(suspend_state_t state);
191#else /* !CONFIG_SUSPEND */
192#define mem_sleep_current PM_SUSPEND_ON
193
194static inline int suspend_devices_and_enter(suspend_state_t state)
195{
196 return -ENOSYS;
197}
198#endif /* !CONFIG_SUSPEND */
199
200#ifdef CONFIG_PM_TEST_SUSPEND
201/* kernel/power/suspend_test.c */
202extern void suspend_test_start(void);
203extern void suspend_test_finish(const char *label);
204#else /* !CONFIG_PM_TEST_SUSPEND */
205static inline void suspend_test_start(void) {}
206static inline void suspend_test_finish(const char *label) {}
207#endif /* !CONFIG_PM_TEST_SUSPEND */
208
209#ifdef CONFIG_PM_SLEEP
210/* kernel/power/main.c */
211extern int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down);
212extern int pm_notifier_call_chain(unsigned long val);
213void pm_restrict_gfp_mask(void);
214void pm_restore_gfp_mask(void);
215#else
216static inline void pm_restrict_gfp_mask(void) {}
217static inline void pm_restore_gfp_mask(void) {}
218#endif
219
220#ifdef CONFIG_HIGHMEM
221int restore_highmem(void);
222#else
223static inline unsigned int count_highmem_pages(void) { return 0; }
224static inline int restore_highmem(void) { return 0; }
225#endif
226
227/*
228 * Suspend test levels
229 */
230enum {
231 /* keep first */
232 TEST_NONE,
233 TEST_CORE,
234 TEST_CPUS,
235 TEST_PLATFORM,
236 TEST_DEVICES,
237 TEST_FREEZER,
238 /* keep last */
239 __TEST_AFTER_LAST
240};
241
242#define TEST_FIRST TEST_NONE
243#define TEST_MAX (__TEST_AFTER_LAST - 1)
244
245#ifdef CONFIG_PM_SLEEP_DEBUG
246extern int pm_test_level;
247#else
248#define pm_test_level (TEST_NONE)
249#endif
250
251#ifdef CONFIG_SUSPEND_FREEZER
252static inline int suspend_freeze_processes(void)
253{
254 int error;
255
256 error = freeze_processes();
257 /*
258 * freeze_processes() automatically thaws every task if freezing
259 * fails. So we need not do anything extra upon error.
260 */
261 if (error)
262 return error;
263
264 error = freeze_kernel_threads();
265 /*
266 * freeze_kernel_threads() thaws only kernel threads upon freezing
267 * failure. So we have to thaw the userspace tasks ourselves.
268 */
269 if (error)
270 thaw_processes();
271
272 return error;
273}
274
275static inline void suspend_thaw_processes(void)
276{
277 thaw_processes();
278}
279#else
280static inline int suspend_freeze_processes(void)
281{
282 return 0;
283}
284
285static inline void suspend_thaw_processes(void)
286{
287}
288#endif
289
290#ifdef CONFIG_PM_AUTOSLEEP
291
292/* kernel/power/autosleep.c */
293extern int pm_autosleep_init(void);
294extern int pm_autosleep_lock(void);
295extern void pm_autosleep_unlock(void);
296extern suspend_state_t pm_autosleep_state(void);
297extern int pm_autosleep_set_state(suspend_state_t state);
298
299#else /* !CONFIG_PM_AUTOSLEEP */
300
301static inline int pm_autosleep_init(void) { return 0; }
302static inline int pm_autosleep_lock(void) { return 0; }
303static inline void pm_autosleep_unlock(void) {}
304static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
305
306#endif /* !CONFIG_PM_AUTOSLEEP */
307
308#ifdef CONFIG_PM_WAKELOCKS
309
310/* kernel/power/wakelock.c */
311extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
312extern int pm_wake_lock(const char *buf);
313extern int pm_wake_unlock(const char *buf);
314
315#endif /* !CONFIG_PM_WAKELOCKS */
316
317static inline int pm_sleep_disable_secondary_cpus(void)
318{
319 cpuidle_pause();
320 return suspend_disable_secondary_cpus();
321}
322
323static inline void pm_sleep_enable_secondary_cpus(void)
324{
325 suspend_enable_secondary_cpus();
326 cpuidle_resume();
327}
328

source code of linux/kernel/power/power.h