mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-29 23:53:32 +00:00
80b0ca98f9
A lot of architectures reuse the same simple ioremap implementation, so start lifting the most simple variant to lib/ioremap.c. It provides ioremap_prot and iounmap, plus a default ioremap that uses prot_noncached, although that can be overridden by asm/io.h. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Palmer Dabbelt <palmer@dabbelt.com>
272 lines
6.1 KiB
C
272 lines
6.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* 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_p4d_capable;
|
|
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_p4d_supported())
|
|
ioremap_p4d_capable = 1;
|
|
if (arch_ioremap_pud_supported())
|
|
ioremap_pud_capable = 1;
|
|
if (arch_ioremap_pmd_supported())
|
|
ioremap_pmd_capable = 1;
|
|
}
|
|
}
|
|
|
|
static inline int ioremap_p4d_enabled(void)
|
|
{
|
|
return ioremap_p4d_capable;
|
|
}
|
|
|
|
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_p4d_enabled(void) { return 0; }
|
|
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 int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr,
|
|
pgprot_t prot)
|
|
{
|
|
if (!ioremap_pmd_enabled())
|
|
return 0;
|
|
|
|
if ((end - addr) != PMD_SIZE)
|
|
return 0;
|
|
|
|
if (!IS_ALIGNED(addr, PMD_SIZE))
|
|
return 0;
|
|
|
|
if (!IS_ALIGNED(phys_addr, PMD_SIZE))
|
|
return 0;
|
|
|
|
if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
|
|
return 0;
|
|
|
|
return pmd_set_huge(pmd, phys_addr, prot);
|
|
}
|
|
|
|
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;
|
|
|
|
pmd = pmd_alloc(&init_mm, pud, addr);
|
|
if (!pmd)
|
|
return -ENOMEM;
|
|
do {
|
|
next = pmd_addr_end(addr, end);
|
|
|
|
if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot))
|
|
continue;
|
|
|
|
if (ioremap_pte_range(pmd, addr, next, phys_addr, prot))
|
|
return -ENOMEM;
|
|
} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
|
|
return 0;
|
|
}
|
|
|
|
static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr,
|
|
pgprot_t prot)
|
|
{
|
|
if (!ioremap_pud_enabled())
|
|
return 0;
|
|
|
|
if ((end - addr) != PUD_SIZE)
|
|
return 0;
|
|
|
|
if (!IS_ALIGNED(addr, PUD_SIZE))
|
|
return 0;
|
|
|
|
if (!IS_ALIGNED(phys_addr, PUD_SIZE))
|
|
return 0;
|
|
|
|
if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
|
|
return 0;
|
|
|
|
return pud_set_huge(pud, phys_addr, prot);
|
|
}
|
|
|
|
static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
|
|
{
|
|
pud_t *pud;
|
|
unsigned long next;
|
|
|
|
pud = pud_alloc(&init_mm, p4d, addr);
|
|
if (!pud)
|
|
return -ENOMEM;
|
|
do {
|
|
next = pud_addr_end(addr, end);
|
|
|
|
if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot))
|
|
continue;
|
|
|
|
if (ioremap_pmd_range(pud, addr, next, phys_addr, prot))
|
|
return -ENOMEM;
|
|
} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
|
|
return 0;
|
|
}
|
|
|
|
static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr,
|
|
pgprot_t prot)
|
|
{
|
|
if (!ioremap_p4d_enabled())
|
|
return 0;
|
|
|
|
if ((end - addr) != P4D_SIZE)
|
|
return 0;
|
|
|
|
if (!IS_ALIGNED(addr, P4D_SIZE))
|
|
return 0;
|
|
|
|
if (!IS_ALIGNED(phys_addr, P4D_SIZE))
|
|
return 0;
|
|
|
|
if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
|
|
return 0;
|
|
|
|
return p4d_set_huge(p4d, phys_addr, prot);
|
|
}
|
|
|
|
static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
|
|
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
|
|
{
|
|
p4d_t *p4d;
|
|
unsigned long next;
|
|
|
|
p4d = p4d_alloc(&init_mm, pgd, addr);
|
|
if (!p4d)
|
|
return -ENOMEM;
|
|
do {
|
|
next = p4d_addr_end(addr, end);
|
|
|
|
if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot))
|
|
continue;
|
|
|
|
if (ioremap_pud_range(p4d, addr, next, phys_addr, prot))
|
|
return -ENOMEM;
|
|
} while (p4d++, phys_addr += (next - addr), 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;
|
|
|
|
might_sleep();
|
|
BUG_ON(addr >= end);
|
|
|
|
start = addr;
|
|
pgd = pgd_offset_k(addr);
|
|
do {
|
|
next = pgd_addr_end(addr, end);
|
|
err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot);
|
|
if (err)
|
|
break;
|
|
} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
|
|
|
|
flush_cache_vmap(start, end);
|
|
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_GENERIC_IOREMAP
|
|
void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
|
|
{
|
|
unsigned long offset, vaddr;
|
|
phys_addr_t last_addr;
|
|
struct vm_struct *area;
|
|
|
|
/* Disallow wrap-around or zero size */
|
|
last_addr = addr + size - 1;
|
|
if (!size || last_addr < addr)
|
|
return NULL;
|
|
|
|
/* Page-align mappings */
|
|
offset = addr & (~PAGE_MASK);
|
|
addr -= offset;
|
|
size = PAGE_ALIGN(size + offset);
|
|
|
|
area = get_vm_area_caller(size, VM_IOREMAP,
|
|
__builtin_return_address(0));
|
|
if (!area)
|
|
return NULL;
|
|
vaddr = (unsigned long)area->addr;
|
|
|
|
if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) {
|
|
free_vm_area(area);
|
|
return NULL;
|
|
}
|
|
|
|
return (void __iomem *)(vaddr + offset);
|
|
}
|
|
EXPORT_SYMBOL(ioremap_prot);
|
|
|
|
void iounmap(volatile void __iomem *addr)
|
|
{
|
|
vunmap((void *)((unsigned long)addr & PAGE_MASK));
|
|
}
|
|
EXPORT_SYMBOL(iounmap);
|
|
#endif /* CONFIG_GENERIC_IOREMAP */
|