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csky: Fixup io-range page attribute for mmap("/dev/mem") 

Some user space drivers need accessing IO address and IO remap need
SO(strong order) page-attribute to make IO operation correct. So we
need add SO-page-attr for all non-memory address.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reported-by: Fan Xiaodong <xiaodong.fan@boyahualu.com>
This commit is contained in:
Guo Ren 2019-01-30 20:13:11 +08:00
parent 0f231dcfc6
commit 76d21d186a
2 changed files with 19 additions and 0 deletions
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5
arch/csky/include/asm/pgtable.h
View File

@ -241,6 +241,11 @@ static inline pte_t pte_mkyoung(pte_t pte)
#define pgd_index(address) ((address) >> PGDIR_SHIFT)
#define __HAVE_PHYS_MEM_ACCESS_PROT
struct file;
extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot);
/*
* Macro to make mark a page protection value as "uncacheable". Note
* that "protection" is really a misnomer here as the protection value

14
arch/csky/mm/ioremap.c
View File

@ -46,3 +46,17 @@ void iounmap(void __iomem *addr)
vunmap((void *)((unsigned long)addr & PAGE_MASK));
}
EXPORT_SYMBOL(iounmap);
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
if (!pfn_valid(pfn)) {
vma_prot.pgprot |= _PAGE_SO;
return pgprot_noncached(vma_prot);
} else if (file->f_flags & O_SYNC) {
return pgprot_noncached(vma_prot);
}
return vma_prot;
}
EXPORT_SYMBOL(phys_mem_access_prot);