diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 5498a6d88ba2..412a1e04a922 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -321,6 +322,37 @@ acpi_map_lookup_virt(void __iomem *virt, acpi_size size) return NULL; } +#ifndef CONFIG_IA64 +#define should_use_kmap(pfn) page_is_ram(pfn) +#else +/* ioremap will take care of cache attributes */ +#define should_use_kmap(pfn) 0 +#endif + +static void __iomem *acpi_map(acpi_physical_address pg_off, unsigned long pg_sz) +{ + unsigned long pfn; + + pfn = pg_off >> PAGE_SHIFT; + if (should_use_kmap(pfn)) { + if (pg_sz > PAGE_SIZE) + return NULL; + return (void __iomem __force *)kmap(pfn_to_page(pfn)); + } else + return acpi_os_ioremap(pg_off, pg_sz); +} + +static void acpi_unmap(acpi_physical_address pg_off, void __iomem *vaddr) +{ + unsigned long pfn; + + pfn = pg_off >> PAGE_SHIFT; + if (page_is_ram(pfn)) + kunmap(pfn_to_page(pfn)); + else + iounmap(vaddr); +} + void __iomem *__init_refok acpi_os_map_memory(acpi_physical_address phys, acpi_size size) { @@ -353,7 +385,7 @@ acpi_os_map_memory(acpi_physical_address phys, acpi_size size) pg_off = round_down(phys, PAGE_SIZE); pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off; - virt = acpi_os_ioremap(pg_off, pg_sz); + virt = acpi_map(pg_off, pg_sz); if (!virt) { mutex_unlock(&acpi_ioremap_lock); kfree(map); @@ -384,7 +416,7 @@ static void acpi_os_map_cleanup(struct acpi_ioremap *map) { if (!map->refcount) { synchronize_rcu(); - iounmap(map->virt); + acpi_unmap(map->phys, map->virt); kfree(map); } }