| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef _XEN_MULTICALLS_H |
| 3 | #define _XEN_MULTICALLS_H |
| 4 | |
| 5 | #include <trace/events/xen.h> |
| 6 | |
| 7 | #include "xen-ops.h" |
| 8 | |
| 9 | /* Multicalls */ |
| 10 | struct multicall_space |
| 11 | { |
| 12 | struct multicall_entry *mc; |
| 13 | void *args; |
| 14 | }; |
| 15 | |
| 16 | /* Allocate room for a multicall and its args */ |
| 17 | struct multicall_space __xen_mc_entry(size_t args); |
| 18 | |
| 19 | DECLARE_PER_CPU(unsigned long, xen_mc_irq_flags); |
| 20 | |
| 21 | /* Call to start a batch of multiple __xen_mc_entry()s. Must be |
| 22 | paired with xen_mc_issue() */ |
| 23 | static inline void xen_mc_batch(void) |
| 24 | { |
| 25 | unsigned long flags; |
| 26 | |
| 27 | /* need to disable interrupts until this entry is complete */ |
| 28 | local_irq_save(flags); |
| 29 | trace_xen_mc_batch(paravirt_get_lazy_mode()); |
| 30 | __this_cpu_write(xen_mc_irq_flags, flags); |
| 31 | } |
| 32 | |
| 33 | static inline struct multicall_space xen_mc_entry(size_t args) |
| 34 | { |
| 35 | xen_mc_batch(); |
| 36 | return __xen_mc_entry(args); |
| 37 | } |
| 38 | |
| 39 | /* Flush all pending multicalls */ |
| 40 | void xen_mc_flush(void); |
| 41 | |
| 42 | /* Issue a multicall if we're not in a lazy mode */ |
| 43 | static inline void xen_mc_issue(unsigned mode) |
| 44 | { |
| 45 | trace_xen_mc_issue(mode); |
| 46 | |
| 47 | if ((paravirt_get_lazy_mode() & mode) == 0) |
| 48 | xen_mc_flush(); |
| 49 | |
| 50 | /* restore flags saved in xen_mc_batch */ |
| 51 | local_irq_restore(this_cpu_read(xen_mc_irq_flags)); |
| 52 | } |
| 53 | |
| 54 | /* Set up a callback to be called when the current batch is flushed */ |
| 55 | void xen_mc_callback(void (*fn)(void *), void *data); |
| 56 | |
| 57 | /* |
| 58 | * Try to extend the arguments of the previous multicall command. The |
| 59 | * previous command's op must match. If it does, then it attempts to |
| 60 | * extend the argument space allocated to the multicall entry by |
| 61 | * arg_size bytes. |
| 62 | * |
| 63 | * The returned multicall_space will return with mc pointing to the |
| 64 | * command on success, or NULL on failure, and args pointing to the |
| 65 | * newly allocated space. |
| 66 | */ |
| 67 | struct multicall_space xen_mc_extend_args(unsigned long op, size_t arg_size); |
| 68 | |
| 69 | #endif /* _XEN_MULTICALLS_H */ |