Commit 76d21d18 authored by Guo Ren's avatar Guo Ren

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: default avatarGuo Ren <ren_guo@c-sky.com>
Reported-by: default avatarFan Xiaodong <xiaodong.fan@boyahualu.com>
parent 0f231dcf
......@@ -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
......
......@@ -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);
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