export __get_user_pages_fast() function

This function is used by KVM to pin process's page in the atomic context.

Define the 'weak' function to avoid other architecture not support it

Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This commit is contained in:
Xiao Guangrong 2010-08-22 19:08:57 +08:00 committed by Avi Kivity
parent f392eb2546
commit 45888a0c6e

View File

@ -245,6 +245,19 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
}
#endif
/*
* Like get_user_pages_fast() except its IRQ-safe in that it won't fall
* back to the regular GUP.
* If the architecture not support this fucntion, simply return with no
* page pinned
*/
int __attribute__((weak)) __get_user_pages_fast(unsigned long start,
int nr_pages, int write, struct page **pages)
{
return 0;
}
EXPORT_SYMBOL_GPL(__get_user_pages_fast);
/**
* get_user_pages_fast() - pin user pages in memory
* @start: starting user address