diff options
Diffstat (limited to 'drivers/acpi/acpica/exregion.c')
| -rw-r--r-- | drivers/acpi/acpica/exregion.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/acpi/acpica/exregion.c b/drivers/acpi/acpica/exregion.c index 1db2c0bfde0b..0a01e19c3190 100644 --- a/drivers/acpi/acpica/exregion.c +++ b/drivers/acpi/acpica/exregion.c @@ -142,9 +142,9 @@ acpi_ex_system_memory_space_handler(u32 function, } /* - * Attempt to map from the requested address to the end of the region. - * However, we will never map more than one page, nor will we cross - * a page boundary. + * October 2009: Attempt to map from the requested address to the + * end of the region. However, we will never map more than one + * page, nor will we cross a page boundary. */ map_length = (acpi_size) ((mem_info->address + mem_info->length) - address); @@ -154,7 +154,11 @@ acpi_ex_system_memory_space_handler(u32 function, * a page boundary, just map up to the page boundary, do not cross. * On some systems, crossing a page boundary while mapping regions * can cause warnings if the pages have different attributes - * due to resource management + * due to resource management. + * + * This has the added benefit of constraining a single mapping to + * one page, which is similar to the original code that used a 4k + * maximum window. */ page_boundary_map_length = ACPI_ROUND_UP(address, ACPI_DEFAULT_PAGE_SIZE) - address; |