mirror of
https://github.com/xemu-project/xemu.git
synced 2024-12-05 10:16:50 +00:00
bac3b21218
Yes, we don't have a good place to put that stuff. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
118 lines
4.0 KiB
C
118 lines
4.0 KiB
C
/*
|
|
* Postcopy migration for RAM
|
|
*
|
|
* Copyright 2013 Red Hat, Inc. and/or its affiliates
|
|
*
|
|
* Authors:
|
|
* Dave Gilbert <dgilbert@redhat.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2 or later.
|
|
* See the COPYING file in the top-level directory.
|
|
*
|
|
*/
|
|
#ifndef QEMU_POSTCOPY_RAM_H
|
|
#define QEMU_POSTCOPY_RAM_H
|
|
|
|
/* Return true if the host supports everything we need to do postcopy-ram */
|
|
bool postcopy_ram_supported_by_host(void);
|
|
|
|
/*
|
|
* Make all of RAM sensitive to accesses to areas that haven't yet been written
|
|
* and wire up anything necessary to deal with it.
|
|
*/
|
|
int postcopy_ram_enable_notify(MigrationIncomingState *mis);
|
|
|
|
/*
|
|
* Initialise postcopy-ram, setting the RAM to a state where we can go into
|
|
* postcopy later; must be called prior to any precopy.
|
|
* called from ram.c's similarly named ram_postcopy_incoming_init
|
|
*/
|
|
int postcopy_ram_incoming_init(MigrationIncomingState *mis, size_t ram_pages);
|
|
|
|
/*
|
|
* At the end of a migration where postcopy_ram_incoming_init was called.
|
|
*/
|
|
int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis);
|
|
|
|
/*
|
|
* Userfault requires us to mark RAM as NOHUGEPAGE prior to discard
|
|
* however leaving it until after precopy means that most of the precopy
|
|
* data is still THPd
|
|
*/
|
|
int postcopy_ram_prepare_discard(MigrationIncomingState *mis);
|
|
|
|
/*
|
|
* Called at the start of each RAMBlock by the bitmap code.
|
|
* Returns a new PDS
|
|
*/
|
|
PostcopyDiscardState *postcopy_discard_send_init(MigrationState *ms,
|
|
const char *name);
|
|
|
|
/*
|
|
* Called by the bitmap code for each chunk to discard.
|
|
* May send a discard message, may just leave it queued to
|
|
* be sent later.
|
|
* @start,@length: a range of pages in the migration bitmap in the
|
|
* RAM block passed to postcopy_discard_send_init() (length=1 is one page)
|
|
*/
|
|
void postcopy_discard_send_range(MigrationState *ms, PostcopyDiscardState *pds,
|
|
unsigned long start, unsigned long length);
|
|
|
|
/*
|
|
* Called at the end of each RAMBlock by the bitmap code.
|
|
* Sends any outstanding discard messages, frees the PDS.
|
|
*/
|
|
void postcopy_discard_send_finish(MigrationState *ms,
|
|
PostcopyDiscardState *pds);
|
|
|
|
/*
|
|
* Place a page (from) at (host) efficiently
|
|
* There are restrictions on how 'from' must be mapped, in general best
|
|
* to use other postcopy_ routines to allocate.
|
|
* returns 0 on success
|
|
*/
|
|
int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
|
|
size_t pagesize);
|
|
|
|
/*
|
|
* Place a zero page at (host) atomically
|
|
* returns 0 on success
|
|
*/
|
|
int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
|
|
size_t pagesize);
|
|
|
|
/* The current postcopy state is read/set by postcopy_state_get/set
|
|
* which update it atomically.
|
|
* The state is updated as postcopy messages are received, and
|
|
* in general only one thread should be writing to the state at any one
|
|
* time, initially the main thread and then the listen thread;
|
|
* Corner cases are where either thread finishes early and/or errors.
|
|
* The state is checked as messages are received to ensure that
|
|
* the source is sending us messages in the correct order.
|
|
* The state is also used by the RAM reception code to know if it
|
|
* has to place pages atomically, and the cleanup code at the end of
|
|
* the main thread to know if it has to delay cleanup until the end
|
|
* of postcopy.
|
|
*/
|
|
typedef enum {
|
|
POSTCOPY_INCOMING_NONE = 0, /* Initial state - no postcopy */
|
|
POSTCOPY_INCOMING_ADVISE,
|
|
POSTCOPY_INCOMING_DISCARD,
|
|
POSTCOPY_INCOMING_LISTENING,
|
|
POSTCOPY_INCOMING_RUNNING,
|
|
POSTCOPY_INCOMING_END
|
|
} PostcopyState;
|
|
|
|
/*
|
|
* Allocate a page of memory that can be mapped at a later point in time
|
|
* using postcopy_place_page
|
|
* Returns: Pointer to allocated page
|
|
*/
|
|
void *postcopy_get_tmp_page(MigrationIncomingState *mis);
|
|
|
|
PostcopyState postcopy_state_get(void);
|
|
/* Set the state and return the old state */
|
|
PostcopyState postcopy_state_set(PostcopyState new_state);
|
|
|
|
#endif
|