1 #ifndef _XEN_MULTICALLS_H 2 #define _XEN_MULTICALLS_H 3 4 #include <trace/events/xen.h> 5 6 #include "xen-ops.h" 7 8 /* Multicalls */ 9 struct multicall_space 10 { 11 struct multicall_entry *mc; 12 void *args; 13 }; 14 15 /* Allocate room for a multicall and its args */ 16 struct multicall_space __xen_mc_entry(size_t args); 17 18 DECLARE_PER_CPU(unsigned long, xen_mc_irq_flags); 19 20 /* Call to start a batch of multiple __xen_mc_entry()s. Must be 21 paired with xen_mc_issue() */ 22 static inline void xen_mc_batch(void) 23 { 24 unsigned long flags; 25 26 /* need to disable interrupts until this entry is complete */ 27 local_irq_save(flags); 28 trace_xen_mc_batch(paravirt_get_lazy_mode()); 29 __this_cpu_write(xen_mc_irq_flags, flags); 30 } 31 32 static inline struct multicall_space xen_mc_entry(size_t args) 33 { 34 xen_mc_batch(); 35 return __xen_mc_entry(args); 36 } 37 38 /* Flush all pending multicalls */ 39 void xen_mc_flush(void); 40 41 /* Issue a multicall if we're not in a lazy mode */ 42 static inline void xen_mc_issue(unsigned mode) 43 { 44 trace_xen_mc_issue(mode); 45 46 if ((paravirt_get_lazy_mode() & mode) == 0) 47 xen_mc_flush(); 48 49 /* restore flags saved in xen_mc_batch */ 50 local_irq_restore(this_cpu_read(xen_mc_irq_flags)); 51 } 52 53 /* Set up a callback to be called when the current batch is flushed */ 54 void xen_mc_callback(void (*fn)(void *), void *data); 55 56 /* 57 * Try to extend the arguments of the previous multicall command. The 58 * previous command's op must match. If it does, then it attempts to 59 * extend the argument space allocated to the multicall entry by 60 * arg_size bytes. 61 * 62 * The returned multicall_space will return with mc pointing to the 63 * command on success, or NULL on failure, and args pointing to the 64 * newly allocated space. 65 */ 66 struct multicall_space xen_mc_extend_args(unsigned long op, size_t arg_size); 67 68 #endif /* _XEN_MULTICALLS_H */ 69