x86: hv: Add function to allocate zeroed page for Hyper-V

Hyper-V assumes page size to be 4K. While this assumption holds true on
x86 architecture, it might not  be true for ARM64 architecture. Hence
define hyper-v specific function to allocate a zeroed page which can
have a different implementation on ARM64 architecture to handle the
conflict between hyper-v's assumed page size and actual guest page size.

Signed-off-by: Himadri Pandya <himadri18.07@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Himadri Pandya 2019-07-30 09:49:43 +00:00 committed by Sasha Levin
parent 0541a22594
commit fa36dcdf8b
2 changed files with 9 additions and 0 deletions

View File

@ -45,6 +45,14 @@ void *hv_alloc_hyperv_page(void)
}
EXPORT_SYMBOL_GPL(hv_alloc_hyperv_page);
void *hv_alloc_hyperv_zeroed_page(void)
{
BUILD_BUG_ON(PAGE_SIZE != HV_HYP_PAGE_SIZE);
return (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
}
EXPORT_SYMBOL_GPL(hv_alloc_hyperv_zeroed_page);
void hv_free_hyperv_page(unsigned long addr)
{
free_page(addr);

View File

@ -219,6 +219,7 @@ static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu)
void __init hyperv_init(void);
void hyperv_setup_mmu_ops(void);
void *hv_alloc_hyperv_page(void);
void *hv_alloc_hyperv_zeroed_page(void);
void hv_free_hyperv_page(unsigned long addr);
void hyperv_reenlightenment_intr(struct pt_regs *regs);
void set_hv_tscchange_cb(void (*cb)(void));