diff options
| -rw-r--r-- | arch/arm/mm/ioremap.c | 72 | ||||
| -rw-r--r-- | arch/arm/mm/mm.h | 14 | ||||
| -rw-r--r-- | arch/arm/mm/mmu.c | 3 |
3 files changed, 64 insertions, 25 deletions
diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c index bc7d9bd766d..12c7ad215ce 100644 --- a/arch/arm/mm/ioremap.c +++ b/arch/arm/mm/ioremap.c @@ -36,12 +36,6 @@ #include <asm/mach/map.h> #include "mm.h" -/* - * Used by ioremap() and iounmap() code to mark (super)section-mapped - * I/O regions in vm_struct->flags field. - */ -#define VM_ARM_SECTION_MAPPING 0x80000000 - int ioremap_page(unsigned long virt, unsigned long phys, const struct mem_type *mtype) { @@ -201,12 +195,6 @@ void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn, if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SUPERSECTION_MASK)) return NULL; - /* - * Don't allow RAM to be mapped - this causes problems with ARMv6+ - */ - if (WARN_ON(pfn_valid(pfn))) - return NULL; - type = get_mem_type(mtype); if (!type) return NULL; @@ -216,6 +204,34 @@ void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn, */ size = PAGE_ALIGN(offset + size); + /* + * Try to reuse one of the static mapping whenever possible. + */ + read_lock(&vmlist_lock); + for (area = vmlist; area; area = area->next) { + if (!size || (sizeof(phys_addr_t) == 4 && pfn >= 0x100000)) + break; + if (!(area->flags & VM_ARM_STATIC_MAPPING)) + continue; + if ((area->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype)) + continue; + if (__phys_to_pfn(area->phys_addr) > pfn || + __pfn_to_phys(pfn) + size-1 > area->phys_addr + area->size-1) + continue; + /* we can drop the lock here as we know *area is static */ + read_unlock(&vmlist_lock); + addr = (unsigned long)area->addr; + addr += __pfn_to_phys(pfn) - area->phys_addr; + return (void __iomem *) (offset + addr); + } + read_unlock(&vmlist_lock); + + /* + * 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; @@ -313,26 +329,34 @@ __arm_ioremap_exec(unsigned long phys_addr, size_t size, bool cached) void __iounmap(volatile void __iomem *io_addr) { void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr); -#ifndef CONFIG_SMP struct vm_struct *vm; - /* - * If this is a section based mapping we need to handle it - * specially as the VM subsystem does not know how to handle - * such a beast. - */ read_lock(&vmlist_lock); for (vm = vmlist; vm; vm = vm->next) { - if ((vm->flags & VM_IOREMAP) && (vm->addr == addr)) { - if (vm->flags & VM_ARM_SECTION_MAPPING) { - unmap_area_sections((unsigned long)vm->addr, - vm->size); - } + if (vm->addr > addr) break; + if (!(vm->flags & VM_IOREMAP)) + continue; + /* If this is a static mapping we must leave it alone */ + if ((vm->flags & VM_ARM_STATIC_MAPPING) && + (vm->addr <= addr) && (vm->addr + vm->size > addr)) { + read_unlock(&vmlist_lock); + return; } +#ifndef CONFIG_SMP + /* + * If this is a section based mapping we need to handle it + * specially as the VM subsystem does not know how to handle + * such a beast. + */ + if ((vm->addr == addr) && + (vm->flags & VM_ARM_SECTION_MAPPING)) { + unmap_area_sections((unsigned long)vm->addr, vm->size); + break; + } +#endif } read_unlock(&vmlist_lock); -#endif vunmap(addr); } diff --git a/arch/arm/mm/mm.h b/arch/arm/mm/mm.h index ad7cce3bc43..70f6d3ea483 100644 --- a/arch/arm/mm/mm.h +++ b/arch/arm/mm/mm.h @@ -21,6 +21,20 @@ const struct mem_type *get_mem_type(unsigned int type); extern void __flush_dcache_page(struct address_space *mapping, struct page *page); +/* + * ARM specific vm_struct->flags bits. + */ + +/* (super)section-mapped I/O regions used by ioremap()/iounmap() */ +#define VM_ARM_SECTION_MAPPING 0x80000000 + +/* permanent static mappings from iotable_init() */ +#define VM_ARM_STATIC_MAPPING 0x40000000 + +/* mapping type (attributes) for permanent static mappings */ +#define VM_ARM_MTYPE(mt) ((mt) << 20) +#define VM_ARM_MTYPE_MASK (0x1f << 20) + #endif #ifdef CONFIG_ZONE_DMA diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index c61481577ae..27e366af67f 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -749,7 +749,8 @@ void __init iotable_init(struct map_desc *io_desc, int nr) vm->addr = (void *)(md->virtual & PAGE_MASK); vm->size = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK)); vm->phys_addr = __pfn_to_phys(md->pfn); - vm->flags = VM_IOREMAP; + vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING; + vm->flags |= VM_ARM_MTYPE(md->type); vm->caller = iotable_init; vm_area_add_early(vm++); } |