参照元†
- unsigned long pfn
- unsigned long offset
- size_t size
- unsigned int mtype
- void *caller
返り値†
static void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
unsigned long offset, size_t size, unsigned int mtype, void *caller)
{
const struct mem_type *type;
int err;
unsigned long addr;
struct vm_struct *area;
phys_addr_t paddr = __pfn_to_phys(pfn);
#ifndef CONFIG_ARM_LPAE
/*
* High mappings must be supersection aligned
*/
if (pfn >= 0x100000 && (paddr & ~SUPERSECTION_MASK))
return NULL;
#endif
type = get_mem_type(mtype);
if (!type)
return NULL;
/*
* Page align the mapping size, taking account of any offset.
*/
size = PAGE_ALIGN(offset + size);
/*
* Try to reuse one of the static mapping whenever possible.
*/
if (size && !(sizeof(phys_addr_t) == 4 && pfn >= 0x100000)) {
struct static_vm *svm;
svm = find_static_vm_paddr(paddr, size, mtype);
if (svm) {
addr = (unsigned long)svm->vm.addr;
addr += paddr - svm->vm.phys_addr;
return (void __iomem *) (offset + addr);
}
}
/*
* Don't allow RAM to be mapped - this causes problems with ARMv6+
*/
if (WARN_ON(pfn_valid(pfn)))
return NULL;
area = get_vm_area_caller(size, VM_IOREMAP, caller);
if (!area)
return NULL;
addr = (unsigned long)area->addr;
area->phys_addr = paddr;
#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
if (DOMAIN_IO == 0 &&
(((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) ||
cpu_is_xsc3()) && pfn >= 0x100000 &&
!((paddr | size | addr) & ~SUPERSECTION_MASK)) {
area->flags |= VM_ARM_SECTION_MAPPING;
err = remap_area_supersections(addr, pfn, size, type);
} else if (!((paddr | size | addr) & ~PMD_MASK)) {
area->flags |= VM_ARM_SECTION_MAPPING;
err = remap_area_sections(addr, pfn, size, type);
} else
#endif
err = ioremap_page_range(addr, addr + size, paddr,
__pgprot(type->prot_pte));
if (err) {
vunmap((void *)addr);
return NULL;
}
flush_cache_vmap(addr, addr + size);
return (void __iomem *) (offset + addr);
}
コメント†