/* * arch/sh/mm/ioremap.c * * (C) Copyright 1995 1996 Linus Torvalds * (C) Copyright 2005 - 2010 Paul Mundt * * 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 * * This file is subject to the terms and conditions of the GNU General * Public License. See the file "COPYING" in the main directory of this * archive for more details. */ #include <linux/vmalloc.h> #include <linux/module.h> #include <linux/mm.h> #include <linux/pci.h> #include <linux/io.h> #include <asm/page.h> #include <asm/pgalloc.h> #include <asm/addrspace.h> #include <asm/cacheflush.h> #include <asm/tlbflush.h> #include <asm/mmu.h> /* * Remap an arbitrary physical address space into the kernel virtual * address space. Needed when the kernel wants to access high addresses * directly. * * NOTE! We need to allow non-page-aligned mappings too: we will obviously * have to convert them into an offset in a page-aligned mapping, but the * caller shouldn't need to know that small detail. */ void __iomem * __init_refok __ioremap_caller(phys_addr_t phys_addr, unsigned long size, pgprot_t pgprot, void *caller) { struct vm_struct *area; unsigned long offset, last_addr, addr, orig_addr; void __iomem *mapped; /* Don't allow wraparound or zero size */ last_addr = phys_addr + size - 1; if (!size || last_addr < phys_addr) return NULL; /* * If we can't yet use the regular approach, go the fixmap route. */ if (!mem_init_done) return ioremap_fixed(phys_addr, size, pgprot); /* * First try to remap through the PMB. * PMB entries are all pre-faulted. */ mapped = pmb_remap_caller(phys_addr, size, pgprot, caller); if (mapped && !IS_ERR(mapped)) return mapped; /* * Mappings have to be page-aligned */ offset = phys_addr & ~PAGE_MASK; phys_addr &= PAGE_MASK; size = PAGE_ALIGN(last_addr+1) - phys_addr; /* * Ok, go for it.. */ area = get_vm_area_caller(size, VM_IOREMAP, caller); if (!area) return NULL; area->phys_addr = phys_addr; orig_addr = addr = (unsigned long)area->addr; if (ioremap_page_range(addr, addr + size, phys_addr, pgprot)) { vunmap((void *)orig_addr); return NULL; } return (void __iomem *)(offset + (char *)orig_addr); } EXPORT_SYMBOL(__ioremap_caller); /* * Simple checks for non-translatable mappings. */ static inline int iomapping_nontranslatable(unsigned long offset) { #ifdef CONFIG_29BIT /* * In 29-bit mode this includes the fixed P1/P2 areas, as well as * parts of P3. */ if (PXSEG(offset) < P3SEG || offset >= P3_ADDR_MAX) return 1; #endif return 0; } void __iounmap(void __iomem *addr) { unsigned long vaddr = (unsigned long __force)addr; struct vm_struct *p; /* * Nothing to do if there is no translatable mapping. */ if (iomapping_nontranslatable(vaddr)) return; /* * There's no VMA if it's from an early fixed mapping. */ if (iounmap_fixed(addr) == 0) return; /* * If the PMB handled it, there's nothing else to do. */ if (pmb_unmap(addr) == 0) return; p = remove_vm_area((void *)(vaddr & PAGE_MASK)); if (!p) { printk(KERN_ERR "%s: bad address %p\n", __func__, addr); return; } kfree(p); } EXPORT_SYMBOL(__iounmap);