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| author | Jeremy Fitzhardinge <jeremy@goop.org> | 2008-05-27 02:31:27 +0400 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2008-05-27 12:11:38 +0400 |
| commit | 0e91398f2a5d4eb6b07df8115917d0d1cf3e9b58 (patch) | |
| tree | c6a3b31b7bcbbfb55bb2304d8651abdd28cdad54 /arch/x86/xen/suspend.c | |
| parent | 7d88d32a4670af583c896e5ecd3929b78538ca62 (diff) | |
| download | linux-0e91398f2a5d4eb6b07df8115917d0d1cf3e9b58.tar.xz | |
xen: implement save/restore
This patch implements Xen save/restore and migration.
Saving is triggered via xenbus, which is polled in
drivers/xen/manage.c. When a suspend request comes in, the kernel
prepares itself for saving by:
1 - Freeze all processes. This is primarily to prevent any
partially-completed pagetable updates from confusing the suspend
process. If CONFIG_PREEMPT isn't defined, then this isn't necessary.
2 - Suspend xenbus and other devices
3 - Stop_machine, to make sure all the other vcpus are quiescent. The
Xen tools require the domain to run its save off vcpu0.
4 - Within the stop_machine state, it pins any unpinned pgds (under
construction or destruction), performs canonicalizes various other
pieces of state (mostly converting mfns to pfns), and finally
5 - Suspend the domain
Restore reverses the steps used to save the domain, ending when all
the frozen processes are thawed.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/xen/suspend.c')
| -rw-r--r-- | arch/x86/xen/suspend.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c new file mode 100644 index 000000000000..7620a16fe535 --- /dev/null +++ b/arch/x86/xen/suspend.c @@ -0,0 +1,42 @@ +#include <linux/types.h> + +#include <xen/interface/xen.h> +#include <xen/grant_table.h> +#include <xen/events.h> + +#include <asm/xen/hypercall.h> +#include <asm/xen/page.h> + +#include "xen-ops.h" +#include "mmu.h" + +void xen_pre_suspend(void) +{ + xen_start_info->store_mfn = mfn_to_pfn(xen_start_info->store_mfn); + xen_start_info->console.domU.mfn = + mfn_to_pfn(xen_start_info->console.domU.mfn); + + BUG_ON(!irqs_disabled()); + + HYPERVISOR_shared_info = &xen_dummy_shared_info; + if (HYPERVISOR_update_va_mapping(fix_to_virt(FIX_PARAVIRT_BOOTMAP), + __pte_ma(0), 0)) + BUG(); +} + +void xen_post_suspend(int suspend_cancelled) +{ + if (suspend_cancelled) { + xen_start_info->store_mfn = + pfn_to_mfn(xen_start_info->store_mfn); + xen_start_info->console.domU.mfn = + pfn_to_mfn(xen_start_info->console.domU.mfn); + } else { +#ifdef CONFIG_SMP + xen_cpu_initialized_map = cpu_online_map; +#endif + } + + xen_setup_shared_info(); +} + |