linux/arch/arm64/include/asm/sync_bitops.h
Stefano Stabellini 9f54ad6652 arm64/xen: introduce asm/xen header files on arm64
asm/xen/hypercall.h, asm/xen/hypervisor.h, asm/xen/interface.h and
asm/xen/page.h are identical so to avoid code duplication we are just
including the original arm header files here.

asm/xen/events.h is slightly different, so introduce a different file
here (use xchg to implement xchg_xen_ulong and pass regs->pstate to
raw_irqs_disabled_flags).

Also introduce asm/hypervisor.h and asm/sync_bitops.h.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
2013-06-07 10:39:45 +00:00

27 lines
1.1 KiB
C

#ifndef __ASM_SYNC_BITOPS_H__
#define __ASM_SYNC_BITOPS_H__
#include <asm/bitops.h>
#include <asm/cmpxchg.h>
/* sync_bitops functions are equivalent to the SMP implementation of the
* original functions, independently from CONFIG_SMP being defined.
*
* We need them because _set_bit etc are not SMP safe if !CONFIG_SMP. But
* under Xen you might be communicating with a completely external entity
* who might be on another CPU (e.g. two uniprocessor guests communicating
* via event channels and grant tables). So we need a variant of the bit
* ops which are SMP safe even on a UP kernel.
*/
#define sync_set_bit(nr, p) set_bit(nr, p)
#define sync_clear_bit(nr, p) clear_bit(nr, p)
#define sync_change_bit(nr, p) change_bit(nr, p)
#define sync_test_and_set_bit(nr, p) test_and_set_bit(nr, p)
#define sync_test_and_clear_bit(nr, p) test_and_clear_bit(nr, p)
#define sync_test_and_change_bit(nr, p) test_and_change_bit(nr, p)
#define sync_test_bit(nr, addr) test_bit(nr, addr)
#define sync_cmpxchg cmpxchg
#endif