mirror of https://gitee.com/openkylin/linux.git
147 lines
3.3 KiB
C
147 lines
3.3 KiB
C
/*
|
|
* Re-map IO memory to kernel address space so that we can access it.
|
|
* This is needed for high PCI addresses that aren't mapped in the
|
|
* 640k-1MB IO memory area on PC's
|
|
*
|
|
* (C) Copyright 1995 1996 Linus Torvalds
|
|
*/
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/io.h>
|
|
#include <linux/export.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/pgtable.h>
|
|
|
|
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
|
|
static int __read_mostly ioremap_pud_capable;
|
|
static int __read_mostly ioremap_pmd_capable;
|
|
static int __read_mostly ioremap_huge_disabled;
|
|
|
|
static int __init set_nohugeiomap(char *str)
|
|
{
|
|
ioremap_huge_disabled = 1;
|
|
return 0;
|
|
}
|
|
early_param("nohugeiomap", set_nohugeiomap);
|
|
|
|
void __init ioremap_huge_init(void)
|
|
{
|
|
if (!ioremap_huge_disabled) {
|
|
if (arch_ioremap_pud_supported())
|
|
ioremap_pud_capable = 1;
|
|
if (arch_ioremap_pmd_supported())
|
|
ioremap_pmd_capable = 1;
|
|
}
|
|
}
|
|
|
|
static inline int ioremap_pud_enabled(void)
|
|
{
|
|
return ioremap_pud_capable;
|
|
}
|
|
|
|
static inline int ioremap_pmd_enabled(void)
|
|
{
|
|
return ioremap_pmd_capable;
|
|
}
|
|
|
|
#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
|
|
static inline int ioremap_pud_enabled(void) { return 0; }
|
|
static inline int ioremap_pmd_enabled(void) { return 0; }
|
|
#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
|
|
|
|
static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
|
|
{
|
|
pte_t *pte;
|
|
u64 pfn;
|
|
|
|
pfn = phys_addr >> PAGE_SHIFT;
|
|
pte = pte_alloc_kernel(pmd, addr);
|
|
if (!pte)
|
|
return -ENOMEM;
|
|
do {
|
|
BUG_ON(!pte_none(*pte));
|
|
set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
|
|
pfn++;
|
|
} while (pte++, addr += PAGE_SIZE, addr != end);
|
|
return 0;
|
|
}
|
|
|
|
static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
|
|
{
|
|
pmd_t *pmd;
|
|
unsigned long next;
|
|
|
|
phys_addr -= addr;
|
|
pmd = pmd_alloc(&init_mm, pud, addr);
|
|
if (!pmd)
|
|
return -ENOMEM;
|
|
do {
|
|
next = pmd_addr_end(addr, end);
|
|
|
|
if (ioremap_pmd_enabled() &&
|
|
((next - addr) == PMD_SIZE) &&
|
|
IS_ALIGNED(phys_addr + addr, PMD_SIZE)) {
|
|
if (pmd_set_huge(pmd, phys_addr + addr, prot))
|
|
continue;
|
|
}
|
|
|
|
if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
|
|
return -ENOMEM;
|
|
} while (pmd++, addr = next, addr != end);
|
|
return 0;
|
|
}
|
|
|
|
static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
|
|
{
|
|
pud_t *pud;
|
|
unsigned long next;
|
|
|
|
phys_addr -= addr;
|
|
pud = pud_alloc(&init_mm, pgd, addr);
|
|
if (!pud)
|
|
return -ENOMEM;
|
|
do {
|
|
next = pud_addr_end(addr, end);
|
|
|
|
if (ioremap_pud_enabled() &&
|
|
((next - addr) == PUD_SIZE) &&
|
|
IS_ALIGNED(phys_addr + addr, PUD_SIZE)) {
|
|
if (pud_set_huge(pud, phys_addr + addr, prot))
|
|
continue;
|
|
}
|
|
|
|
if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
|
|
return -ENOMEM;
|
|
} while (pud++, addr = next, addr != end);
|
|
return 0;
|
|
}
|
|
|
|
int ioremap_page_range(unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
|
|
{
|
|
pgd_t *pgd;
|
|
unsigned long start;
|
|
unsigned long next;
|
|
int err;
|
|
|
|
BUG_ON(addr >= end);
|
|
|
|
start = addr;
|
|
phys_addr -= addr;
|
|
pgd = pgd_offset_k(addr);
|
|
do {
|
|
next = pgd_addr_end(addr, end);
|
|
err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot);
|
|
if (err)
|
|
break;
|
|
} while (pgd++, addr = next, addr != end);
|
|
|
|
flush_cache_vmap(start, end);
|
|
|
|
return err;
|
|
}
|