diff options
Diffstat (limited to 'include/xen/interface/memory.h')
| -rw-r--r-- | include/xen/interface/memory.h | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index af36ead16817..d3938d3e71f8 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -9,6 +9,8 @@ #ifndef __XEN_PUBLIC_MEMORY_H__ #define __XEN_PUBLIC_MEMORY_H__ +#include <linux/spinlock.h> + /* * Increase or decrease the specified domain's memory reservation. Returns a * -ve errcode on failure, or the # extents successfully allocated or freed. @@ -53,6 +55,48 @@ struct xen_memory_reservation { DEFINE_GUEST_HANDLE_STRUCT(xen_memory_reservation); /* + * An atomic exchange of memory pages. If return code is zero then + * @out.extent_list provides GMFNs of the newly-allocated memory. + * Returns zero on complete success, otherwise a negative error code. + * On complete success then always @nr_exchanged == @in.nr_extents. + * On partial success @nr_exchanged indicates how much work was done. + */ +#define XENMEM_exchange 11 +struct xen_memory_exchange { + /* + * [IN] Details of memory extents to be exchanged (GMFN bases). + * Note that @in.address_bits is ignored and unused. + */ + struct xen_memory_reservation in; + + /* + * [IN/OUT] Details of new memory extents. + * We require that: + * 1. @in.domid == @out.domid + * 2. @in.nr_extents << @in.extent_order == + * @out.nr_extents << @out.extent_order + * 3. @in.extent_start and @out.extent_start lists must not overlap + * 4. @out.extent_start lists GPFN bases to be populated + * 5. @out.extent_start is overwritten with allocated GMFN bases + */ + struct xen_memory_reservation out; + + /* + * [OUT] Number of input extents that were successfully exchanged: + * 1. The first @nr_exchanged input extents were successfully + * deallocated. + * 2. The corresponding first entries in the output extent list correctly + * indicate the GMFNs that were successfully exchanged. + * 3. All other input and output extents are untouched. + * 4. If not all input exents are exchanged then the return code of this + * command will be non-zero. + * 5. THIS FIELD MUST BE INITIALISED TO ZERO BY THE CALLER! + */ + unsigned long nr_exchanged; +}; + +DEFINE_GUEST_HANDLE_STRUCT(xen_memory_exchange); +/* * Returns the maximum machine frame number of mapped RAM in this system. * This command always succeeds (it never returns an error code). * arg == NULL. @@ -142,4 +186,10 @@ struct xen_translate_gpfn_list { }; DEFINE_GUEST_HANDLE_STRUCT(xen_translate_gpfn_list); + +/* + * Prevent the balloon driver from changing the memory reservation + * during a driver critical region. + */ +extern spinlock_t xen_reservation_lock; #endif /* __XEN_PUBLIC_MEMORY_H__ */ |