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@@ -27,17 +27,17 @@ once at a time.
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The ioctl() commands recognized by the device are:
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SNAPSHOT_FREEZE - freeze user space processes (the current process is
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- not frozen); this is required for SNAPSHOT_ATOMIC_SNAPSHOT
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+ not frozen); this is required for SNAPSHOT_CREATE_IMAGE
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and SNAPSHOT_ATOMIC_RESTORE to succeed
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SNAPSHOT_UNFREEZE - thaw user space processes frozen by SNAPSHOT_FREEZE
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-SNAPSHOT_ATOMIC_SNAPSHOT - create a snapshot of the system memory; the
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+SNAPSHOT_CREATE_IMAGE - create a snapshot of the system memory; the
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last argument of ioctl() should be a pointer to an int variable,
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the value of which will indicate whether the call returned after
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creating the snapshot (1) or after restoring the system memory state
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from it (0) (after resume the system finds itself finishing the
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- SNAPSHOT_ATOMIC_SNAPSHOT ioctl() again); after the snapshot
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+ SNAPSHOT_CREATE_IMAGE ioctl() again); after the snapshot
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has been created the read() operation can be used to transfer
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it out of the kernel
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@@ -49,23 +49,23 @@ SNAPSHOT_ATOMIC_RESTORE - restore the system memory state from the
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SNAPSHOT_FREE - free memory allocated for the snapshot image
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-SNAPSHOT_SET_IMAGE_SIZE - set the preferred maximum size of the image
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+SNAPSHOT_PREF_IMAGE_SIZE - set the preferred maximum size of the image
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(the kernel will do its best to ensure the image size will not exceed
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this number, but if it turns out to be impossible, the kernel will
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create the smallest image possible)
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SNAPSHOT_GET_IMAGE_SIZE - return the actual size of the hibernation image
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-SNAPSHOT_AVAIL_SWAP - return the amount of available swap in bytes (the last
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- argument should be a pointer to an unsigned int variable that will
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+SNAPSHOT_AVAIL_SWAP_SIZE - return the amount of available swap in bytes (the
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+ last argument should be a pointer to an unsigned int variable that will
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contain the result if the call is successful).
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-SNAPSHOT_GET_SWAP_PAGE - allocate a swap page from the resume partition
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+SNAPSHOT_ALLOC_SWAP_PAGE - allocate a swap page from the resume partition
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(the last argument should be a pointer to a loff_t variable that
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will contain the swap page offset if the call is successful)
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-SNAPSHOT_FREE_SWAP_PAGES - free all swap pages allocated with
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- SNAPSHOT_GET_SWAP_PAGE
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+SNAPSHOT_FREE_SWAP_PAGES - free all swap pages allocated by
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+ SNAPSHOT_ALLOC_SWAP_PAGE
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SNAPSHOT_SET_SWAP_AREA - set the resume partition and the offset (in <PAGE_SIZE>
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units) from the beginning of the partition at which the swap header is
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@@ -102,7 +102,7 @@ The device's write() operation is used for uploading the system memory snapshot
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into the kernel. It has the same limitations as the read() operation.
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The release() operation frees all memory allocated for the snapshot image
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-and all swap pages allocated with SNAPSHOT_GET_SWAP_PAGE (if any).
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+and all swap pages allocated with SNAPSHOT_ALLOC_SWAP_PAGE (if any).
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Thus it is not necessary to use either SNAPSHOT_FREE or
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SNAPSHOT_FREE_SWAP_PAGES before closing the device (in fact it will also
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unfreeze user space processes frozen by SNAPSHOT_UNFREEZE if they are
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@@ -113,7 +113,7 @@ snapshot image from/to the kernel will use a swap parition, called the resume
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partition, or a swap file as storage space (if a swap file is used, the resume
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partition is the partition that holds this file). However, this is not really
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required, as they can use, for example, a special (blank) suspend partition or
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-a file on a partition that is unmounted before SNAPSHOT_ATOMIC_SNAPSHOT and
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+a file on a partition that is unmounted before SNAPSHOT_CREATE_IMAGE and
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mounted afterwards.
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These utilities MUST NOT make any assumptions regarding the ordering of
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@@ -135,7 +135,7 @@ means, such as checksums, to ensure the integrity of the snapshot image.
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The suspending and resuming utilities MUST lock themselves in memory,
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preferrably using mlockall(), before calling SNAPSHOT_FREEZE.
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-The suspending utility MUST check the value stored by SNAPSHOT_ATOMIC_SNAPSHOT
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+The suspending utility MUST check the value stored by SNAPSHOT_CREATE_IMAGE
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in the memory location pointed to by the last argument of ioctl() and proceed
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in accordance with it:
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1. If the value is 1 (ie. the system memory snapshot has just been
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@@ -149,7 +149,7 @@ in accordance with it:
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image has been saved.
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(b) The suspending utility SHOULD NOT attempt to perform any
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file system operations (including reads) on the file systems
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- that were mounted before SNAPSHOT_ATOMIC_SNAPSHOT has been
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+ that were mounted before SNAPSHOT_CREATE_IMAGE has been
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called. However, it MAY mount a file system that was not
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mounted at that time and perform some operations on it (eg.
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use it for saving the image).
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