Hi,
I am trying to understand remap_pte_range in 2.4.19 kernel. The name of
the function and the comment suggests that a range of pte are cleared and
set to new pages. But the code just clears the ptes and does not
set the pte entry to a new page. Can you please explain me what is
this function suppose to do and when is it used.
Thanks a lot.
Raghu
/*
* maps a range of physical memory into the requested pages. the old *
mappings are removed. any references to nonexistent pages results * in
null mappings (currently treated as "copy-on-access") */
static inline void remap_pte_range(pte_t * pte, unsigned long address,
unsigned long size,
unsigned long phys_addr, pgprot_t prot) {
unsigned long end;
address &= ~PMD_MASK;
end = address + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
do {
struct page *page;
pte_t oldpage;
oldpage = p tep_get_and_clear(pte);
page = virt_to_page(__va(phys_addr));
if ((!VALID_PAGE(page)) || PageReserved(page))
set_pte(pte, mk_pte_phys(phys_addr, prot));
forget_pte(oldpage);
address += PAGE_SIZE;
phys_addr += PAGE_SIZE;
pte++;
} while (address && (address < end));
}
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