diff options
Diffstat (limited to 'Documentation/power/userland-swsusp.txt')
-rw-r--r-- | Documentation/power/userland-swsusp.txt | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/Documentation/power/userland-swsusp.txt b/Documentation/power/userland-swsusp.txt index 0785500e65fb..af52d535a896 100644 --- a/Documentation/power/userland-swsusp.txt +++ b/Documentation/power/userland-swsusp.txt | |||
@@ -27,17 +27,17 @@ once at a time. | |||
27 | The ioctl() commands recognized by the device are: | 27 | The ioctl() commands recognized by the device are: |
28 | 28 | ||
29 | SNAPSHOT_FREEZE - freeze user space processes (the current process is | 29 | SNAPSHOT_FREEZE - freeze user space processes (the current process is |
30 | not frozen); this is required for SNAPSHOT_ATOMIC_SNAPSHOT | 30 | not frozen); this is required for SNAPSHOT_CREATE_IMAGE |
31 | and SNAPSHOT_ATOMIC_RESTORE to succeed | 31 | and SNAPSHOT_ATOMIC_RESTORE to succeed |
32 | 32 | ||
33 | SNAPSHOT_UNFREEZE - thaw user space processes frozen by SNAPSHOT_FREEZE | 33 | SNAPSHOT_UNFREEZE - thaw user space processes frozen by SNAPSHOT_FREEZE |
34 | 34 | ||
35 | SNAPSHOT_ATOMIC_SNAPSHOT - create a snapshot of the system memory; the | 35 | SNAPSHOT_CREATE_IMAGE - create a snapshot of the system memory; the |
36 | last argument of ioctl() should be a pointer to an int variable, | 36 | last argument of ioctl() should be a pointer to an int variable, |
37 | the value of which will indicate whether the call returned after | 37 | the value of which will indicate whether the call returned after |
38 | creating the snapshot (1) or after restoring the system memory state | 38 | creating the snapshot (1) or after restoring the system memory state |
39 | from it (0) (after resume the system finds itself finishing the | 39 | from it (0) (after resume the system finds itself finishing the |
40 | SNAPSHOT_ATOMIC_SNAPSHOT ioctl() again); after the snapshot | 40 | SNAPSHOT_CREATE_IMAGE ioctl() again); after the snapshot |
41 | has been created the read() operation can be used to transfer | 41 | has been created the read() operation can be used to transfer |
42 | it out of the kernel | 42 | it out of the kernel |
43 | 43 | ||
@@ -49,23 +49,23 @@ SNAPSHOT_ATOMIC_RESTORE - restore the system memory state from the | |||
49 | 49 | ||
50 | SNAPSHOT_FREE - free memory allocated for the snapshot image | 50 | SNAPSHOT_FREE - free memory allocated for the snapshot image |
51 | 51 | ||
52 | SNAPSHOT_SET_IMAGE_SIZE - set the preferred maximum size of the image | 52 | SNAPSHOT_PREF_IMAGE_SIZE - set the preferred maximum size of the image |
53 | (the kernel will do its best to ensure the image size will not exceed | 53 | (the kernel will do its best to ensure the image size will not exceed |
54 | this number, but if it turns out to be impossible, the kernel will | 54 | this number, but if it turns out to be impossible, the kernel will |
55 | create the smallest image possible) | 55 | create the smallest image possible) |
56 | 56 | ||
57 | SNAPSHOT_GET_IMAGE_SIZE - return the actual size of the hibernation image | 57 | SNAPSHOT_GET_IMAGE_SIZE - return the actual size of the hibernation image |
58 | 58 | ||
59 | SNAPSHOT_AVAIL_SWAP - return the amount of available swap in bytes (the last | 59 | SNAPSHOT_AVAIL_SWAP_SIZE - return the amount of available swap in bytes (the |
60 | argument should be a pointer to an unsigned int variable that will | 60 | last argument should be a pointer to an unsigned int variable that will |
61 | contain the result if the call is successful). | 61 | contain the result if the call is successful). |
62 | 62 | ||
63 | SNAPSHOT_GET_SWAP_PAGE - allocate a swap page from the resume partition | 63 | SNAPSHOT_ALLOC_SWAP_PAGE - allocate a swap page from the resume partition |
64 | (the last argument should be a pointer to a loff_t variable that | 64 | (the last argument should be a pointer to a loff_t variable that |
65 | will contain the swap page offset if the call is successful) | 65 | will contain the swap page offset if the call is successful) |
66 | 66 | ||
67 | SNAPSHOT_FREE_SWAP_PAGES - free all swap pages allocated with | 67 | SNAPSHOT_FREE_SWAP_PAGES - free all swap pages allocated by |
68 | SNAPSHOT_GET_SWAP_PAGE | 68 | SNAPSHOT_ALLOC_SWAP_PAGE |
69 | 69 | ||
70 | SNAPSHOT_SET_SWAP_AREA - set the resume partition and the offset (in <PAGE_SIZE> | 70 | SNAPSHOT_SET_SWAP_AREA - set the resume partition and the offset (in <PAGE_SIZE> |
71 | units) from the beginning of the partition at which the swap header is | 71 | units) from the beginning of the partition at which the swap header is |
@@ -102,7 +102,7 @@ The device's write() operation is used for uploading the system memory snapshot | |||
102 | into the kernel. It has the same limitations as the read() operation. | 102 | into the kernel. It has the same limitations as the read() operation. |
103 | 103 | ||
104 | The release() operation frees all memory allocated for the snapshot image | 104 | The release() operation frees all memory allocated for the snapshot image |
105 | and all swap pages allocated with SNAPSHOT_GET_SWAP_PAGE (if any). | 105 | and all swap pages allocated with SNAPSHOT_ALLOC_SWAP_PAGE (if any). |
106 | Thus it is not necessary to use either SNAPSHOT_FREE or | 106 | Thus it is not necessary to use either SNAPSHOT_FREE or |
107 | SNAPSHOT_FREE_SWAP_PAGES before closing the device (in fact it will also | 107 | SNAPSHOT_FREE_SWAP_PAGES before closing the device (in fact it will also |
108 | unfreeze user space processes frozen by SNAPSHOT_UNFREEZE if they are | 108 | unfreeze user space processes frozen by SNAPSHOT_UNFREEZE if they are |
@@ -113,7 +113,7 @@ snapshot image from/to the kernel will use a swap parition, called the resume | |||
113 | partition, or a swap file as storage space (if a swap file is used, the resume | 113 | partition, or a swap file as storage space (if a swap file is used, the resume |
114 | partition is the partition that holds this file). However, this is not really | 114 | partition is the partition that holds this file). However, this is not really |
115 | required, as they can use, for example, a special (blank) suspend partition or | 115 | required, as they can use, for example, a special (blank) suspend partition or |
116 | a file on a partition that is unmounted before SNAPSHOT_ATOMIC_SNAPSHOT and | 116 | a file on a partition that is unmounted before SNAPSHOT_CREATE_IMAGE and |
117 | mounted afterwards. | 117 | mounted afterwards. |
118 | 118 | ||
119 | These utilities MUST NOT make any assumptions regarding the ordering of | 119 | These utilities MUST NOT make any assumptions regarding the ordering of |
@@ -135,7 +135,7 @@ means, such as checksums, to ensure the integrity of the snapshot image. | |||
135 | The suspending and resuming utilities MUST lock themselves in memory, | 135 | The suspending and resuming utilities MUST lock themselves in memory, |
136 | preferrably using mlockall(), before calling SNAPSHOT_FREEZE. | 136 | preferrably using mlockall(), before calling SNAPSHOT_FREEZE. |
137 | 137 | ||
138 | The suspending utility MUST check the value stored by SNAPSHOT_ATOMIC_SNAPSHOT | 138 | The suspending utility MUST check the value stored by SNAPSHOT_CREATE_IMAGE |
139 | in the memory location pointed to by the last argument of ioctl() and proceed | 139 | in the memory location pointed to by the last argument of ioctl() and proceed |
140 | in accordance with it: | 140 | in accordance with it: |
141 | 1. If the value is 1 (ie. the system memory snapshot has just been | 141 | 1. If the value is 1 (ie. the system memory snapshot has just been |
@@ -149,7 +149,7 @@ in accordance with it: | |||
149 | image has been saved. | 149 | image has been saved. |
150 | (b) The suspending utility SHOULD NOT attempt to perform any | 150 | (b) The suspending utility SHOULD NOT attempt to perform any |
151 | file system operations (including reads) on the file systems | 151 | file system operations (including reads) on the file systems |
152 | that were mounted before SNAPSHOT_ATOMIC_SNAPSHOT has been | 152 | that were mounted before SNAPSHOT_CREATE_IMAGE has been |
153 | called. However, it MAY mount a file system that was not | 153 | called. However, it MAY mount a file system that was not |
154 | mounted at that time and perform some operations on it (eg. | 154 | mounted at that time and perform some operations on it (eg. |
155 | use it for saving the image). | 155 | use it for saving the image). |